2005-04-16 16:20:36 -06:00
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/*
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* (C) 1997 Linus Torvalds
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2011-05-27 07:28:01 -06:00
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* (C) 1999 Andrea Arcangeli <andrea@suse.de> (dynamic inode allocation)
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2005-04-16 16:20:36 -06:00
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*/
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2011-12-07 11:17:19 -07:00
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#include <linux/export.h>
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2005-04-16 16:20:36 -06:00
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#include <linux/fs.h>
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#include <linux/mm.h>
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#include <linux/backing-dev.h>
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#include <linux/hash.h>
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#include <linux/swap.h>
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#include <linux/security.h>
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#include <linux/cdev.h>
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#include <linux/bootmem.h>
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2009-05-21 15:01:26 -06:00
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#include <linux/fsnotify.h>
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2006-01-09 21:52:17 -07:00
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#include <linux/mount.h>
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2009-06-08 17:50:45 -06:00
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#include <linux/posix_acl.h>
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2011-05-22 10:54:21 -06:00
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#include <linux/prefetch.h>
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2011-05-27 07:28:01 -06:00
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#include <linux/buffer_head.h> /* for inode_has_buffers */
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2011-11-21 04:11:32 -07:00
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#include <linux/ratelimit.h>
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2011-03-22 05:23:41 -06:00
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#include "internal.h"
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2005-04-16 16:20:36 -06:00
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2011-03-22 05:23:36 -06:00
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/*
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2011-05-27 07:28:01 -06:00
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* Inode locking rules:
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2011-03-22 05:23:36 -06:00
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*
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* inode->i_lock protects:
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* inode->i_state, inode->i_hash, __iget()
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2011-07-07 22:14:40 -06:00
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* inode->i_sb->s_inode_lru_lock protects:
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2011-07-07 22:14:39 -06:00
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* inode->i_sb->s_inode_lru, inode->i_lru
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2011-03-22 05:23:40 -06:00
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* inode_sb_list_lock protects:
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* sb->s_inodes, inode->i_sb_list
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2011-04-21 18:19:44 -06:00
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* bdi->wb.list_lock protects:
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2011-03-22 05:23:41 -06:00
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* bdi->wb.b_{dirty,io,more_io}, inode->i_wb_list
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2011-03-22 05:23:42 -06:00
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* inode_hash_lock protects:
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* inode_hashtable, inode->i_hash
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2011-03-22 05:23:36 -06:00
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*
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* Lock ordering:
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2011-03-22 05:23:40 -06:00
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*
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* inode_sb_list_lock
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* inode->i_lock
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2011-07-07 22:14:40 -06:00
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* inode->i_sb->s_inode_lru_lock
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2011-03-22 05:23:41 -06:00
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*
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2011-04-21 18:19:44 -06:00
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* bdi->wb.list_lock
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2011-03-22 05:23:41 -06:00
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* inode->i_lock
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2011-03-22 05:23:42 -06:00
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*
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* inode_hash_lock
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* inode_sb_list_lock
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* inode->i_lock
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*
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* iunique_lock
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* inode_hash_lock
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2011-03-22 05:23:36 -06:00
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*/
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2006-03-26 02:37:24 -07:00
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static unsigned int i_hash_mask __read_mostly;
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static unsigned int i_hash_shift __read_mostly;
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2011-03-22 05:23:42 -06:00
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static struct hlist_head *inode_hashtable __read_mostly;
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static __cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_hash_lock);
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2005-04-16 16:20:36 -06:00
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2011-03-22 05:23:40 -06:00
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__cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_sb_list_lock);
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2011-04-05 15:51:48 -06:00
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/*
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* Empty aops. Can be used for the cases where the user does not
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* define any of the address_space operations.
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*/
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const struct address_space_operations empty_aops = {
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};
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EXPORT_SYMBOL(empty_aops);
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2005-04-16 16:20:36 -06:00
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/*
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* Statistics gathering..
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*/
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struct inodes_stat_t inodes_stat;
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fs: use fast counters for vfs caches
percpu_counter library generates quite nasty code, so unless you need
to dynamically allocate counters or take fast approximate value, a
simple per cpu set of counters is much better.
The percpu_counter can never be made to work as well, because it has an
indirection from pointer to percpu memory, and it can't use direct
this_cpu_inc interfaces because it doesn't use static PER_CPU data, so
code will always be worse.
In the fastpath, it is the difference between this:
incl %gs:nr_dentry # nr_dentry
and this:
movl percpu_counter_batch(%rip), %edx # percpu_counter_batch,
movl $1, %esi #,
movq $nr_dentry, %rdi #,
call __percpu_counter_add # (plus I clobber registers)
__percpu_counter_add:
pushq %rbp #
movq %rsp, %rbp #,
subq $32, %rsp #,
movq %rbx, -24(%rbp) #,
movq %r12, -16(%rbp) #,
movq %r13, -8(%rbp) #,
movq %rdi, %rbx # fbc, fbc
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
incl -8124(%rax) # <variable>.preempt_count
movq 32(%rdi), %r12 # <variable>.counters, tcp_ptr__
#APP
# 78 "lib/percpu_counter.c" 1
add %gs:this_cpu_off, %r12 # this_cpu_off, tcp_ptr__
# 0 "" 2
#NO_APP
movslq (%r12),%r13 #* tcp_ptr__, tmp73
movslq %edx,%rax # batch, batch
addq %rsi, %r13 # amount, count
cmpq %rax, %r13 # batch, count
jge .L27 #,
negl %edx # tmp76
movslq %edx,%rdx # tmp76, tmp77
cmpq %rdx, %r13 # tmp77, count
jg .L28 #,
.L27:
movq %rbx, %rdi # fbc,
call _raw_spin_lock #
addq %r13, 8(%rbx) # count, <variable>.count
movq %rbx, %rdi # fbc,
movl $0, (%r12) #,* tcp_ptr__
call _raw_spin_unlock #
.L29:
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
decl -8124(%rax) # <variable>.preempt_count
movq -8136(%rax), %rax #, D.14625
testb $8, %al #, D.14625
jne .L32 #,
.L31:
movq -24(%rbp), %rbx #,
movq -16(%rbp), %r12 #,
movq -8(%rbp), %r13 #,
leave
ret
.p2align 4,,10
.p2align 3
.L28:
movl %r13d, (%r12) # count,*
jmp .L29 #
.L32:
call preempt_schedule #
.p2align 4,,6
jmp .L31 #
.size __percpu_counter_add, .-__percpu_counter_add
.p2align 4,,15
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-06 23:49:19 -07:00
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static DEFINE_PER_CPU(unsigned int, nr_inodes);
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2011-07-07 22:14:38 -06:00
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static DEFINE_PER_CPU(unsigned int, nr_unused);
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2010-10-23 03:03:02 -06:00
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2009-03-31 08:05:54 -06:00
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static struct kmem_cache *inode_cachep __read_mostly;
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2005-04-16 16:20:36 -06:00
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fs: use fast counters for vfs caches
percpu_counter library generates quite nasty code, so unless you need
to dynamically allocate counters or take fast approximate value, a
simple per cpu set of counters is much better.
The percpu_counter can never be made to work as well, because it has an
indirection from pointer to percpu memory, and it can't use direct
this_cpu_inc interfaces because it doesn't use static PER_CPU data, so
code will always be worse.
In the fastpath, it is the difference between this:
incl %gs:nr_dentry # nr_dentry
and this:
movl percpu_counter_batch(%rip), %edx # percpu_counter_batch,
movl $1, %esi #,
movq $nr_dentry, %rdi #,
call __percpu_counter_add # (plus I clobber registers)
__percpu_counter_add:
pushq %rbp #
movq %rsp, %rbp #,
subq $32, %rsp #,
movq %rbx, -24(%rbp) #,
movq %r12, -16(%rbp) #,
movq %r13, -8(%rbp) #,
movq %rdi, %rbx # fbc, fbc
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
incl -8124(%rax) # <variable>.preempt_count
movq 32(%rdi), %r12 # <variable>.counters, tcp_ptr__
#APP
# 78 "lib/percpu_counter.c" 1
add %gs:this_cpu_off, %r12 # this_cpu_off, tcp_ptr__
# 0 "" 2
#NO_APP
movslq (%r12),%r13 #* tcp_ptr__, tmp73
movslq %edx,%rax # batch, batch
addq %rsi, %r13 # amount, count
cmpq %rax, %r13 # batch, count
jge .L27 #,
negl %edx # tmp76
movslq %edx,%rdx # tmp76, tmp77
cmpq %rdx, %r13 # tmp77, count
jg .L28 #,
.L27:
movq %rbx, %rdi # fbc,
call _raw_spin_lock #
addq %r13, 8(%rbx) # count, <variable>.count
movq %rbx, %rdi # fbc,
movl $0, (%r12) #,* tcp_ptr__
call _raw_spin_unlock #
.L29:
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
decl -8124(%rax) # <variable>.preempt_count
movq -8136(%rax), %rax #, D.14625
testb $8, %al #, D.14625
jne .L32 #,
.L31:
movq -24(%rbp), %rbx #,
movq -16(%rbp), %r12 #,
movq -8(%rbp), %r13 #,
leave
ret
.p2align 4,,10
.p2align 3
.L28:
movl %r13d, (%r12) # count,*
jmp .L29 #
.L32:
call preempt_schedule #
.p2align 4,,6
jmp .L31 #
.size __percpu_counter_add, .-__percpu_counter_add
.p2align 4,,15
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-06 23:49:19 -07:00
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static int get_nr_inodes(void)
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2010-10-23 03:03:02 -06:00
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{
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fs: use fast counters for vfs caches
percpu_counter library generates quite nasty code, so unless you need
to dynamically allocate counters or take fast approximate value, a
simple per cpu set of counters is much better.
The percpu_counter can never be made to work as well, because it has an
indirection from pointer to percpu memory, and it can't use direct
this_cpu_inc interfaces because it doesn't use static PER_CPU data, so
code will always be worse.
In the fastpath, it is the difference between this:
incl %gs:nr_dentry # nr_dentry
and this:
movl percpu_counter_batch(%rip), %edx # percpu_counter_batch,
movl $1, %esi #,
movq $nr_dentry, %rdi #,
call __percpu_counter_add # (plus I clobber registers)
__percpu_counter_add:
pushq %rbp #
movq %rsp, %rbp #,
subq $32, %rsp #,
movq %rbx, -24(%rbp) #,
movq %r12, -16(%rbp) #,
movq %r13, -8(%rbp) #,
movq %rdi, %rbx # fbc, fbc
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
incl -8124(%rax) # <variable>.preempt_count
movq 32(%rdi), %r12 # <variable>.counters, tcp_ptr__
#APP
# 78 "lib/percpu_counter.c" 1
add %gs:this_cpu_off, %r12 # this_cpu_off, tcp_ptr__
# 0 "" 2
#NO_APP
movslq (%r12),%r13 #* tcp_ptr__, tmp73
movslq %edx,%rax # batch, batch
addq %rsi, %r13 # amount, count
cmpq %rax, %r13 # batch, count
jge .L27 #,
negl %edx # tmp76
movslq %edx,%rdx # tmp76, tmp77
cmpq %rdx, %r13 # tmp77, count
jg .L28 #,
.L27:
movq %rbx, %rdi # fbc,
call _raw_spin_lock #
addq %r13, 8(%rbx) # count, <variable>.count
movq %rbx, %rdi # fbc,
movl $0, (%r12) #,* tcp_ptr__
call _raw_spin_unlock #
.L29:
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
decl -8124(%rax) # <variable>.preempt_count
movq -8136(%rax), %rax #, D.14625
testb $8, %al #, D.14625
jne .L32 #,
.L31:
movq -24(%rbp), %rbx #,
movq -16(%rbp), %r12 #,
movq -8(%rbp), %r13 #,
leave
ret
.p2align 4,,10
.p2align 3
.L28:
movl %r13d, (%r12) # count,*
jmp .L29 #
.L32:
call preempt_schedule #
.p2align 4,,6
jmp .L31 #
.size __percpu_counter_add, .-__percpu_counter_add
.p2align 4,,15
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-06 23:49:19 -07:00
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int i;
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int sum = 0;
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for_each_possible_cpu(i)
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sum += per_cpu(nr_inodes, i);
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return sum < 0 ? 0 : sum;
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2010-10-23 03:03:02 -06:00
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}
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static inline int get_nr_inodes_unused(void)
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{
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2011-07-07 22:14:38 -06:00
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int i;
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int sum = 0;
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for_each_possible_cpu(i)
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sum += per_cpu(nr_unused, i);
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return sum < 0 ? 0 : sum;
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2010-10-23 03:03:02 -06:00
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}
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int get_nr_dirty_inodes(void)
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{
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fs: use fast counters for vfs caches
percpu_counter library generates quite nasty code, so unless you need
to dynamically allocate counters or take fast approximate value, a
simple per cpu set of counters is much better.
The percpu_counter can never be made to work as well, because it has an
indirection from pointer to percpu memory, and it can't use direct
this_cpu_inc interfaces because it doesn't use static PER_CPU data, so
code will always be worse.
In the fastpath, it is the difference between this:
incl %gs:nr_dentry # nr_dentry
and this:
movl percpu_counter_batch(%rip), %edx # percpu_counter_batch,
movl $1, %esi #,
movq $nr_dentry, %rdi #,
call __percpu_counter_add # (plus I clobber registers)
__percpu_counter_add:
pushq %rbp #
movq %rsp, %rbp #,
subq $32, %rsp #,
movq %rbx, -24(%rbp) #,
movq %r12, -16(%rbp) #,
movq %r13, -8(%rbp) #,
movq %rdi, %rbx # fbc, fbc
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
incl -8124(%rax) # <variable>.preempt_count
movq 32(%rdi), %r12 # <variable>.counters, tcp_ptr__
#APP
# 78 "lib/percpu_counter.c" 1
add %gs:this_cpu_off, %r12 # this_cpu_off, tcp_ptr__
# 0 "" 2
#NO_APP
movslq (%r12),%r13 #* tcp_ptr__, tmp73
movslq %edx,%rax # batch, batch
addq %rsi, %r13 # amount, count
cmpq %rax, %r13 # batch, count
jge .L27 #,
negl %edx # tmp76
movslq %edx,%rdx # tmp76, tmp77
cmpq %rdx, %r13 # tmp77, count
jg .L28 #,
.L27:
movq %rbx, %rdi # fbc,
call _raw_spin_lock #
addq %r13, 8(%rbx) # count, <variable>.count
movq %rbx, %rdi # fbc,
movl $0, (%r12) #,* tcp_ptr__
call _raw_spin_unlock #
.L29:
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
decl -8124(%rax) # <variable>.preempt_count
movq -8136(%rax), %rax #, D.14625
testb $8, %al #, D.14625
jne .L32 #,
.L31:
movq -24(%rbp), %rbx #,
movq -16(%rbp), %r12 #,
movq -8(%rbp), %r13 #,
leave
ret
.p2align 4,,10
.p2align 3
.L28:
movl %r13d, (%r12) # count,*
jmp .L29 #
.L32:
call preempt_schedule #
.p2align 4,,6
jmp .L31 #
.size __percpu_counter_add, .-__percpu_counter_add
.p2align 4,,15
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-06 23:49:19 -07:00
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/* not actually dirty inodes, but a wild approximation */
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2010-10-23 03:03:02 -06:00
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int nr_dirty = get_nr_inodes() - get_nr_inodes_unused();
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return nr_dirty > 0 ? nr_dirty : 0;
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}
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/*
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* Handle nr_inode sysctl
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*/
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#ifdef CONFIG_SYSCTL
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int proc_nr_inodes(ctl_table *table, int write,
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void __user *buffer, size_t *lenp, loff_t *ppos)
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{
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inodes_stat.nr_inodes = get_nr_inodes();
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2011-07-07 22:14:38 -06:00
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inodes_stat.nr_unused = get_nr_inodes_unused();
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2010-10-23 03:03:02 -06:00
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return proc_dointvec(table, write, buffer, lenp, ppos);
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}
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#endif
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2008-10-30 00:32:23 -06:00
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/**
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* inode_init_always - perform inode structure intialisation
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2009-01-06 15:41:13 -07:00
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* @sb: superblock inode belongs to
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* @inode: inode to initialise
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2008-10-30 00:32:23 -06:00
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*
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* These are initializations that need to be done on every inode
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* allocation as the fields are not initialised by slab allocation.
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*/
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2009-08-07 11:38:25 -06:00
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int inode_init_always(struct super_block *sb, struct inode *inode)
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2005-04-16 16:20:36 -06:00
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{
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2009-09-21 18:01:11 -06:00
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static const struct inode_operations empty_iops;
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2006-03-28 02:56:41 -07:00
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static const struct file_operations empty_fops;
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2009-03-31 08:05:54 -06:00
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struct address_space *const mapping = &inode->i_data;
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2008-10-30 00:32:23 -06:00
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inode->i_sb = sb;
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inode->i_blkbits = sb->s_blocksize_bits;
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inode->i_flags = 0;
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atomic_set(&inode->i_count, 1);
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inode->i_op = &empty_iops;
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inode->i_fop = &empty_fops;
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2011-10-28 06:13:30 -06:00
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inode->__i_nlink = 1;
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2011-08-06 23:45:50 -06:00
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inode->i_opflags = 0;
|
2012-02-08 08:07:50 -07:00
|
|
|
i_uid_write(inode, 0);
|
|
|
|
i_gid_write(inode, 0);
|
2008-10-30 00:32:23 -06:00
|
|
|
atomic_set(&inode->i_writecount, 0);
|
|
|
|
inode->i_size = 0;
|
|
|
|
inode->i_blocks = 0;
|
|
|
|
inode->i_bytes = 0;
|
|
|
|
inode->i_generation = 0;
|
2005-04-16 16:20:36 -06:00
|
|
|
#ifdef CONFIG_QUOTA
|
2008-10-30 00:32:23 -06:00
|
|
|
memset(&inode->i_dquot, 0, sizeof(inode->i_dquot));
|
2005-04-16 16:20:36 -06:00
|
|
|
#endif
|
2008-10-30 00:32:23 -06:00
|
|
|
inode->i_pipe = NULL;
|
|
|
|
inode->i_bdev = NULL;
|
|
|
|
inode->i_cdev = NULL;
|
|
|
|
inode->i_rdev = 0;
|
|
|
|
inode->dirtied_when = 0;
|
2009-02-04 07:06:57 -07:00
|
|
|
|
|
|
|
if (security_inode_alloc(inode))
|
2009-08-07 11:38:25 -06:00
|
|
|
goto out;
|
2008-10-30 00:32:23 -06:00
|
|
|
spin_lock_init(&inode->i_lock);
|
|
|
|
lockdep_set_class(&inode->i_lock, &sb->s_type->i_lock_key);
|
|
|
|
|
|
|
|
mutex_init(&inode->i_mutex);
|
|
|
|
lockdep_set_class(&inode->i_mutex, &sb->s_type->i_mutex_key);
|
|
|
|
|
2011-06-24 12:29:43 -06:00
|
|
|
atomic_set(&inode->i_dio_count, 0);
|
2008-10-30 00:32:23 -06:00
|
|
|
|
|
|
|
mapping->a_ops = &empty_aops;
|
|
|
|
mapping->host = inode;
|
|
|
|
mapping->flags = 0;
|
2009-01-06 15:39:23 -07:00
|
|
|
mapping_set_gfp_mask(mapping, GFP_HIGHUSER_MOVABLE);
|
2008-10-30 00:32:23 -06:00
|
|
|
mapping->assoc_mapping = NULL;
|
|
|
|
mapping->backing_dev_info = &default_backing_dev_info;
|
|
|
|
mapping->writeback_index = 0;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If the block_device provides a backing_dev_info for client
|
|
|
|
* inodes then use that. Otherwise the inode share the bdev's
|
|
|
|
* backing_dev_info.
|
|
|
|
*/
|
|
|
|
if (sb->s_bdev) {
|
|
|
|
struct backing_dev_info *bdi;
|
|
|
|
|
2009-09-15 01:43:56 -06:00
|
|
|
bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info;
|
2008-10-30 00:32:23 -06:00
|
|
|
mapping->backing_dev_info = bdi;
|
|
|
|
}
|
|
|
|
inode->i_private = NULL;
|
|
|
|
inode->i_mapping = mapping;
|
2012-06-09 11:51:19 -06:00
|
|
|
INIT_HLIST_HEAD(&inode->i_dentry); /* buggered by rcu freeing */
|
2009-06-08 17:50:45 -06:00
|
|
|
#ifdef CONFIG_FS_POSIX_ACL
|
|
|
|
inode->i_acl = inode->i_default_acl = ACL_NOT_CACHED;
|
|
|
|
#endif
|
2008-10-30 00:32:23 -06:00
|
|
|
|
2009-05-21 15:01:26 -06:00
|
|
|
#ifdef CONFIG_FSNOTIFY
|
|
|
|
inode->i_fsnotify_mask = 0;
|
|
|
|
#endif
|
|
|
|
|
fs: use fast counters for vfs caches
percpu_counter library generates quite nasty code, so unless you need
to dynamically allocate counters or take fast approximate value, a
simple per cpu set of counters is much better.
The percpu_counter can never be made to work as well, because it has an
indirection from pointer to percpu memory, and it can't use direct
this_cpu_inc interfaces because it doesn't use static PER_CPU data, so
code will always be worse.
In the fastpath, it is the difference between this:
incl %gs:nr_dentry # nr_dentry
and this:
movl percpu_counter_batch(%rip), %edx # percpu_counter_batch,
movl $1, %esi #,
movq $nr_dentry, %rdi #,
call __percpu_counter_add # (plus I clobber registers)
__percpu_counter_add:
pushq %rbp #
movq %rsp, %rbp #,
subq $32, %rsp #,
movq %rbx, -24(%rbp) #,
movq %r12, -16(%rbp) #,
movq %r13, -8(%rbp) #,
movq %rdi, %rbx # fbc, fbc
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
incl -8124(%rax) # <variable>.preempt_count
movq 32(%rdi), %r12 # <variable>.counters, tcp_ptr__
#APP
# 78 "lib/percpu_counter.c" 1
add %gs:this_cpu_off, %r12 # this_cpu_off, tcp_ptr__
# 0 "" 2
#NO_APP
movslq (%r12),%r13 #* tcp_ptr__, tmp73
movslq %edx,%rax # batch, batch
addq %rsi, %r13 # amount, count
cmpq %rax, %r13 # batch, count
jge .L27 #,
negl %edx # tmp76
movslq %edx,%rdx # tmp76, tmp77
cmpq %rdx, %r13 # tmp77, count
jg .L28 #,
.L27:
movq %rbx, %rdi # fbc,
call _raw_spin_lock #
addq %r13, 8(%rbx) # count, <variable>.count
movq %rbx, %rdi # fbc,
movl $0, (%r12) #,* tcp_ptr__
call _raw_spin_unlock #
.L29:
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
decl -8124(%rax) # <variable>.preempt_count
movq -8136(%rax), %rax #, D.14625
testb $8, %al #, D.14625
jne .L32 #,
.L31:
movq -24(%rbp), %rbx #,
movq -16(%rbp), %r12 #,
movq -8(%rbp), %r13 #,
leave
ret
.p2align 4,,10
.p2align 3
.L28:
movl %r13d, (%r12) # count,*
jmp .L29 #
.L32:
call preempt_schedule #
.p2align 4,,6
jmp .L31 #
.size __percpu_counter_add, .-__percpu_counter_add
.p2align 4,,15
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-06 23:49:19 -07:00
|
|
|
this_cpu_inc(nr_inodes);
|
2010-10-23 03:03:02 -06:00
|
|
|
|
2009-08-07 11:38:25 -06:00
|
|
|
return 0;
|
|
|
|
out:
|
|
|
|
return -ENOMEM;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2008-10-30 00:32:23 -06:00
|
|
|
EXPORT_SYMBOL(inode_init_always);
|
|
|
|
|
|
|
|
static struct inode *alloc_inode(struct super_block *sb)
|
|
|
|
{
|
|
|
|
struct inode *inode;
|
|
|
|
|
|
|
|
if (sb->s_op->alloc_inode)
|
|
|
|
inode = sb->s_op->alloc_inode(sb);
|
|
|
|
else
|
|
|
|
inode = kmem_cache_alloc(inode_cachep, GFP_KERNEL);
|
|
|
|
|
2009-08-07 11:38:25 -06:00
|
|
|
if (!inode)
|
|
|
|
return NULL;
|
|
|
|
|
|
|
|
if (unlikely(inode_init_always(sb, inode))) {
|
|
|
|
if (inode->i_sb->s_op->destroy_inode)
|
|
|
|
inode->i_sb->s_op->destroy_inode(inode);
|
|
|
|
else
|
|
|
|
kmem_cache_free(inode_cachep, inode);
|
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
|
|
|
|
return inode;
|
2008-10-30 00:32:23 -06:00
|
|
|
}
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-01-06 23:49:50 -07:00
|
|
|
void free_inode_nonrcu(struct inode *inode)
|
|
|
|
{
|
|
|
|
kmem_cache_free(inode_cachep, inode);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(free_inode_nonrcu);
|
|
|
|
|
2009-08-07 11:38:29 -06:00
|
|
|
void __destroy_inode(struct inode *inode)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2006-04-02 05:38:18 -06:00
|
|
|
BUG_ON(inode_has_buffers(inode));
|
2005-04-16 16:20:36 -06:00
|
|
|
security_inode_free(inode);
|
2009-05-21 15:01:26 -06:00
|
|
|
fsnotify_inode_delete(inode);
|
2011-11-21 04:11:32 -07:00
|
|
|
if (!inode->i_nlink) {
|
|
|
|
WARN_ON(atomic_long_read(&inode->i_sb->s_remove_count) == 0);
|
|
|
|
atomic_long_dec(&inode->i_sb->s_remove_count);
|
|
|
|
}
|
|
|
|
|
2009-06-08 17:50:45 -06:00
|
|
|
#ifdef CONFIG_FS_POSIX_ACL
|
|
|
|
if (inode->i_acl && inode->i_acl != ACL_NOT_CACHED)
|
|
|
|
posix_acl_release(inode->i_acl);
|
|
|
|
if (inode->i_default_acl && inode->i_default_acl != ACL_NOT_CACHED)
|
|
|
|
posix_acl_release(inode->i_default_acl);
|
|
|
|
#endif
|
fs: use fast counters for vfs caches
percpu_counter library generates quite nasty code, so unless you need
to dynamically allocate counters or take fast approximate value, a
simple per cpu set of counters is much better.
The percpu_counter can never be made to work as well, because it has an
indirection from pointer to percpu memory, and it can't use direct
this_cpu_inc interfaces because it doesn't use static PER_CPU data, so
code will always be worse.
In the fastpath, it is the difference between this:
incl %gs:nr_dentry # nr_dentry
and this:
movl percpu_counter_batch(%rip), %edx # percpu_counter_batch,
movl $1, %esi #,
movq $nr_dentry, %rdi #,
call __percpu_counter_add # (plus I clobber registers)
__percpu_counter_add:
pushq %rbp #
movq %rsp, %rbp #,
subq $32, %rsp #,
movq %rbx, -24(%rbp) #,
movq %r12, -16(%rbp) #,
movq %r13, -8(%rbp) #,
movq %rdi, %rbx # fbc, fbc
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
incl -8124(%rax) # <variable>.preempt_count
movq 32(%rdi), %r12 # <variable>.counters, tcp_ptr__
#APP
# 78 "lib/percpu_counter.c" 1
add %gs:this_cpu_off, %r12 # this_cpu_off, tcp_ptr__
# 0 "" 2
#NO_APP
movslq (%r12),%r13 #* tcp_ptr__, tmp73
movslq %edx,%rax # batch, batch
addq %rsi, %r13 # amount, count
cmpq %rax, %r13 # batch, count
jge .L27 #,
negl %edx # tmp76
movslq %edx,%rdx # tmp76, tmp77
cmpq %rdx, %r13 # tmp77, count
jg .L28 #,
.L27:
movq %rbx, %rdi # fbc,
call _raw_spin_lock #
addq %r13, 8(%rbx) # count, <variable>.count
movq %rbx, %rdi # fbc,
movl $0, (%r12) #,* tcp_ptr__
call _raw_spin_unlock #
.L29:
#APP
# 216 "/home/npiggin/usr/src/linux-2.6/arch/x86/include/asm/thread_info.h" 1
movq %gs:kernel_stack,%rax #, pfo_ret__
# 0 "" 2
#NO_APP
decl -8124(%rax) # <variable>.preempt_count
movq -8136(%rax), %rax #, D.14625
testb $8, %al #, D.14625
jne .L32 #,
.L31:
movq -24(%rbp), %rbx #,
movq -16(%rbp), %r12 #,
movq -8(%rbp), %r13 #,
leave
ret
.p2align 4,,10
.p2align 3
.L28:
movl %r13d, (%r12) # count,*
jmp .L29 #
.L32:
call preempt_schedule #
.p2align 4,,6
jmp .L31 #
.size __percpu_counter_add, .-__percpu_counter_add
.p2align 4,,15
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-06 23:49:19 -07:00
|
|
|
this_cpu_dec(nr_inodes);
|
2009-08-07 11:38:29 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(__destroy_inode);
|
|
|
|
|
2011-01-06 23:49:49 -07:00
|
|
|
static void i_callback(struct rcu_head *head)
|
|
|
|
{
|
|
|
|
struct inode *inode = container_of(head, struct inode, i_rcu);
|
|
|
|
kmem_cache_free(inode_cachep, inode);
|
|
|
|
}
|
|
|
|
|
2010-10-06 02:48:55 -06:00
|
|
|
static void destroy_inode(struct inode *inode)
|
2009-08-07 11:38:29 -06:00
|
|
|
{
|
2010-10-20 18:49:30 -06:00
|
|
|
BUG_ON(!list_empty(&inode->i_lru));
|
2009-08-07 11:38:29 -06:00
|
|
|
__destroy_inode(inode);
|
2005-04-16 16:20:36 -06:00
|
|
|
if (inode->i_sb->s_op->destroy_inode)
|
|
|
|
inode->i_sb->s_op->destroy_inode(inode);
|
|
|
|
else
|
2011-01-06 23:49:49 -07:00
|
|
|
call_rcu(&inode->i_rcu, i_callback);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
2011-11-21 04:11:32 -07:00
|
|
|
/**
|
|
|
|
* drop_nlink - directly drop an inode's link count
|
|
|
|
* @inode: inode
|
|
|
|
*
|
|
|
|
* This is a low-level filesystem helper to replace any
|
|
|
|
* direct filesystem manipulation of i_nlink. In cases
|
|
|
|
* where we are attempting to track writes to the
|
|
|
|
* filesystem, a decrement to zero means an imminent
|
|
|
|
* write when the file is truncated and actually unlinked
|
|
|
|
* on the filesystem.
|
|
|
|
*/
|
|
|
|
void drop_nlink(struct inode *inode)
|
|
|
|
{
|
|
|
|
WARN_ON(inode->i_nlink == 0);
|
|
|
|
inode->__i_nlink--;
|
|
|
|
if (!inode->i_nlink)
|
|
|
|
atomic_long_inc(&inode->i_sb->s_remove_count);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(drop_nlink);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* clear_nlink - directly zero an inode's link count
|
|
|
|
* @inode: inode
|
|
|
|
*
|
|
|
|
* This is a low-level filesystem helper to replace any
|
|
|
|
* direct filesystem manipulation of i_nlink. See
|
|
|
|
* drop_nlink() for why we care about i_nlink hitting zero.
|
|
|
|
*/
|
|
|
|
void clear_nlink(struct inode *inode)
|
|
|
|
{
|
|
|
|
if (inode->i_nlink) {
|
|
|
|
inode->__i_nlink = 0;
|
|
|
|
atomic_long_inc(&inode->i_sb->s_remove_count);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(clear_nlink);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* set_nlink - directly set an inode's link count
|
|
|
|
* @inode: inode
|
|
|
|
* @nlink: new nlink (should be non-zero)
|
|
|
|
*
|
|
|
|
* This is a low-level filesystem helper to replace any
|
|
|
|
* direct filesystem manipulation of i_nlink.
|
|
|
|
*/
|
|
|
|
void set_nlink(struct inode *inode, unsigned int nlink)
|
|
|
|
{
|
|
|
|
if (!nlink) {
|
|
|
|
clear_nlink(inode);
|
|
|
|
} else {
|
|
|
|
/* Yes, some filesystems do change nlink from zero to one */
|
|
|
|
if (inode->i_nlink == 0)
|
|
|
|
atomic_long_dec(&inode->i_sb->s_remove_count);
|
|
|
|
|
|
|
|
inode->__i_nlink = nlink;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(set_nlink);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* inc_nlink - directly increment an inode's link count
|
|
|
|
* @inode: inode
|
|
|
|
*
|
|
|
|
* This is a low-level filesystem helper to replace any
|
|
|
|
* direct filesystem manipulation of i_nlink. Currently,
|
|
|
|
* it is only here for parity with dec_nlink().
|
|
|
|
*/
|
|
|
|
void inc_nlink(struct inode *inode)
|
|
|
|
{
|
|
|
|
if (WARN_ON(inode->i_nlink == 0))
|
|
|
|
atomic_long_dec(&inode->i_sb->s_remove_count);
|
|
|
|
|
|
|
|
inode->__i_nlink++;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(inc_nlink);
|
|
|
|
|
2011-02-23 05:49:47 -07:00
|
|
|
void address_space_init_once(struct address_space *mapping)
|
|
|
|
{
|
|
|
|
memset(mapping, 0, sizeof(*mapping));
|
|
|
|
INIT_RADIX_TREE(&mapping->page_tree, GFP_ATOMIC);
|
|
|
|
spin_lock_init(&mapping->tree_lock);
|
2011-05-24 18:12:06 -06:00
|
|
|
mutex_init(&mapping->i_mmap_mutex);
|
2011-02-23 05:49:47 -07:00
|
|
|
INIT_LIST_HEAD(&mapping->private_list);
|
|
|
|
spin_lock_init(&mapping->private_lock);
|
2012-10-08 17:31:25 -06:00
|
|
|
mapping->i_mmap = RB_ROOT;
|
2011-02-23 05:49:47 -07:00
|
|
|
INIT_LIST_HEAD(&mapping->i_mmap_nonlinear);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(address_space_init_once);
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/*
|
|
|
|
* These are initializations that only need to be done
|
|
|
|
* once, because the fields are idempotent across use
|
|
|
|
* of the inode, so let the slab aware of that.
|
|
|
|
*/
|
|
|
|
void inode_init_once(struct inode *inode)
|
|
|
|
{
|
|
|
|
memset(inode, 0, sizeof(*inode));
|
|
|
|
INIT_HLIST_NODE(&inode->i_hash);
|
|
|
|
INIT_LIST_HEAD(&inode->i_devices);
|
2010-10-20 18:49:30 -06:00
|
|
|
INIT_LIST_HEAD(&inode->i_wb_list);
|
|
|
|
INIT_LIST_HEAD(&inode->i_lru);
|
2011-02-23 05:49:47 -07:00
|
|
|
address_space_init_once(&inode->i_data);
|
2005-04-16 16:20:36 -06:00
|
|
|
i_size_ordered_init(inode);
|
2009-05-21 15:01:26 -06:00
|
|
|
#ifdef CONFIG_FSNOTIFY
|
2009-12-17 19:24:24 -07:00
|
|
|
INIT_HLIST_HEAD(&inode->i_fsnotify_marks);
|
2009-05-21 15:01:26 -06:00
|
|
|
#endif
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(inode_init_once);
|
|
|
|
|
2008-07-25 20:45:34 -06:00
|
|
|
static void init_once(void *foo)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2009-03-31 08:05:54 -06:00
|
|
|
struct inode *inode = (struct inode *) foo;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2007-05-16 23:10:57 -06:00
|
|
|
inode_init_once(inode);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
2011-03-22 05:23:36 -06:00
|
|
|
* inode->i_lock must be held
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2009-03-31 08:05:54 -06:00
|
|
|
void __iget(struct inode *inode)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2010-10-23 04:55:17 -06:00
|
|
|
atomic_inc(&inode->i_count);
|
|
|
|
}
|
2010-05-14 03:49:22 -06:00
|
|
|
|
2010-10-23 09:11:40 -06:00
|
|
|
/*
|
|
|
|
* get additional reference to inode; caller must already hold one.
|
|
|
|
*/
|
|
|
|
void ihold(struct inode *inode)
|
|
|
|
{
|
|
|
|
WARN_ON(atomic_inc_return(&inode->i_count) < 2);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(ihold);
|
|
|
|
|
2010-10-23 04:55:17 -06:00
|
|
|
static void inode_lru_list_add(struct inode *inode)
|
|
|
|
{
|
2011-07-07 22:14:40 -06:00
|
|
|
spin_lock(&inode->i_sb->s_inode_lru_lock);
|
2010-10-20 18:49:30 -06:00
|
|
|
if (list_empty(&inode->i_lru)) {
|
2011-07-07 22:14:39 -06:00
|
|
|
list_add(&inode->i_lru, &inode->i_sb->s_inode_lru);
|
|
|
|
inode->i_sb->s_nr_inodes_unused++;
|
2011-07-07 22:14:38 -06:00
|
|
|
this_cpu_inc(nr_unused);
|
2010-10-23 04:55:17 -06:00
|
|
|
}
|
2011-07-07 22:14:40 -06:00
|
|
|
spin_unlock(&inode->i_sb->s_inode_lru_lock);
|
2010-10-23 04:55:17 -06:00
|
|
|
}
|
2010-05-14 03:49:22 -06:00
|
|
|
|
2010-10-23 04:55:17 -06:00
|
|
|
static void inode_lru_list_del(struct inode *inode)
|
|
|
|
{
|
2011-07-07 22:14:40 -06:00
|
|
|
spin_lock(&inode->i_sb->s_inode_lru_lock);
|
2010-10-20 18:49:30 -06:00
|
|
|
if (!list_empty(&inode->i_lru)) {
|
|
|
|
list_del_init(&inode->i_lru);
|
2011-07-07 22:14:39 -06:00
|
|
|
inode->i_sb->s_nr_inodes_unused--;
|
2011-07-07 22:14:38 -06:00
|
|
|
this_cpu_dec(nr_unused);
|
2010-10-23 04:55:17 -06:00
|
|
|
}
|
2011-07-07 22:14:40 -06:00
|
|
|
spin_unlock(&inode->i_sb->s_inode_lru_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
2010-10-23 05:15:32 -06:00
|
|
|
/**
|
|
|
|
* inode_sb_list_add - add inode to the superblock list of inodes
|
|
|
|
* @inode: inode to add
|
|
|
|
*/
|
|
|
|
void inode_sb_list_add(struct inode *inode)
|
|
|
|
{
|
2011-03-22 05:23:40 -06:00
|
|
|
spin_lock(&inode_sb_list_lock);
|
|
|
|
list_add(&inode->i_sb_list, &inode->i_sb->s_inodes);
|
|
|
|
spin_unlock(&inode_sb_list_lock);
|
2010-10-23 05:15:32 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(inode_sb_list_add);
|
|
|
|
|
2011-03-22 05:23:40 -06:00
|
|
|
static inline void inode_sb_list_del(struct inode *inode)
|
2010-10-23 05:15:32 -06:00
|
|
|
{
|
2011-07-26 03:36:34 -06:00
|
|
|
if (!list_empty(&inode->i_sb_list)) {
|
|
|
|
spin_lock(&inode_sb_list_lock);
|
|
|
|
list_del_init(&inode->i_sb_list);
|
|
|
|
spin_unlock(&inode_sb_list_lock);
|
|
|
|
}
|
2010-10-23 05:15:32 -06:00
|
|
|
}
|
|
|
|
|
2010-10-23 04:58:09 -06:00
|
|
|
static unsigned long hash(struct super_block *sb, unsigned long hashval)
|
|
|
|
{
|
|
|
|
unsigned long tmp;
|
|
|
|
|
|
|
|
tmp = (hashval * (unsigned long)sb) ^ (GOLDEN_RATIO_PRIME + hashval) /
|
|
|
|
L1_CACHE_BYTES;
|
2011-05-27 07:28:01 -06:00
|
|
|
tmp = tmp ^ ((tmp ^ GOLDEN_RATIO_PRIME) >> i_hash_shift);
|
|
|
|
return tmp & i_hash_mask;
|
2010-10-23 04:58:09 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* __insert_inode_hash - hash an inode
|
|
|
|
* @inode: unhashed inode
|
|
|
|
* @hashval: unsigned long value used to locate this object in the
|
|
|
|
* inode_hashtable.
|
|
|
|
*
|
|
|
|
* Add an inode to the inode hash for this superblock.
|
|
|
|
*/
|
|
|
|
void __insert_inode_hash(struct inode *inode, unsigned long hashval)
|
|
|
|
{
|
2010-10-23 05:15:32 -06:00
|
|
|
struct hlist_head *b = inode_hashtable + hash(inode->i_sb, hashval);
|
|
|
|
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
2010-10-23 05:15:32 -06:00
|
|
|
hlist_add_head(&inode->i_hash, b);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2010-10-23 04:58:09 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(__insert_inode_hash);
|
|
|
|
|
|
|
|
/**
|
2011-07-27 22:41:09 -06:00
|
|
|
* __remove_inode_hash - remove an inode from the hash
|
2010-10-23 04:58:09 -06:00
|
|
|
* @inode: inode to unhash
|
|
|
|
*
|
|
|
|
* Remove an inode from the superblock.
|
|
|
|
*/
|
2011-07-27 22:41:09 -06:00
|
|
|
void __remove_inode_hash(struct inode *inode)
|
2010-10-23 04:58:09 -06:00
|
|
|
{
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
2010-10-23 04:58:09 -06:00
|
|
|
hlist_del_init(&inode->i_hash);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2010-10-23 04:58:09 -06:00
|
|
|
}
|
2011-07-27 22:41:09 -06:00
|
|
|
EXPORT_SYMBOL(__remove_inode_hash);
|
2010-10-23 04:58:09 -06:00
|
|
|
|
2012-05-03 06:48:02 -06:00
|
|
|
void clear_inode(struct inode *inode)
|
2010-06-04 18:55:25 -06:00
|
|
|
{
|
|
|
|
might_sleep();
|
2011-06-27 17:18:10 -06:00
|
|
|
/*
|
|
|
|
* We have to cycle tree_lock here because reclaim can be still in the
|
|
|
|
* process of removing the last page (in __delete_from_page_cache())
|
|
|
|
* and we must not free mapping under it.
|
|
|
|
*/
|
|
|
|
spin_lock_irq(&inode->i_data.tree_lock);
|
2010-06-04 18:55:25 -06:00
|
|
|
BUG_ON(inode->i_data.nrpages);
|
2011-06-27 17:18:10 -06:00
|
|
|
spin_unlock_irq(&inode->i_data.tree_lock);
|
2010-06-04 18:55:25 -06:00
|
|
|
BUG_ON(!list_empty(&inode->i_data.private_list));
|
|
|
|
BUG_ON(!(inode->i_state & I_FREEING));
|
|
|
|
BUG_ON(inode->i_state & I_CLEAR);
|
2011-01-06 23:49:49 -07:00
|
|
|
/* don't need i_lock here, no concurrent mods to i_state */
|
2010-06-04 18:55:25 -06:00
|
|
|
inode->i_state = I_FREEING | I_CLEAR;
|
|
|
|
}
|
2012-05-03 06:48:02 -06:00
|
|
|
EXPORT_SYMBOL(clear_inode);
|
2010-06-04 18:55:25 -06:00
|
|
|
|
2011-03-22 05:23:37 -06:00
|
|
|
/*
|
|
|
|
* Free the inode passed in, removing it from the lists it is still connected
|
|
|
|
* to. We remove any pages still attached to the inode and wait for any IO that
|
|
|
|
* is still in progress before finally destroying the inode.
|
|
|
|
*
|
|
|
|
* An inode must already be marked I_FREEING so that we avoid the inode being
|
|
|
|
* moved back onto lists if we race with other code that manipulates the lists
|
|
|
|
* (e.g. writeback_single_inode). The caller is responsible for setting this.
|
|
|
|
*
|
|
|
|
* An inode must already be removed from the LRU list before being evicted from
|
|
|
|
* the cache. This should occur atomically with setting the I_FREEING state
|
|
|
|
* flag, so no inodes here should ever be on the LRU when being evicted.
|
|
|
|
*/
|
2010-06-07 11:21:05 -06:00
|
|
|
static void evict(struct inode *inode)
|
2010-06-04 17:33:20 -06:00
|
|
|
{
|
|
|
|
const struct super_operations *op = inode->i_sb->s_op;
|
|
|
|
|
2011-03-22 05:23:37 -06:00
|
|
|
BUG_ON(!(inode->i_state & I_FREEING));
|
|
|
|
BUG_ON(!list_empty(&inode->i_lru));
|
|
|
|
|
2011-07-27 22:11:47 -06:00
|
|
|
if (!list_empty(&inode->i_wb_list))
|
|
|
|
inode_wb_list_del(inode);
|
|
|
|
|
2011-03-22 05:23:40 -06:00
|
|
|
inode_sb_list_del(inode);
|
|
|
|
|
2012-05-03 06:48:03 -06:00
|
|
|
/*
|
|
|
|
* Wait for flusher thread to be done with the inode so that filesystem
|
|
|
|
* does not start destroying it while writeback is still running. Since
|
|
|
|
* the inode has I_FREEING set, flusher thread won't start new work on
|
|
|
|
* the inode. We just have to wait for running writeback to finish.
|
|
|
|
*/
|
|
|
|
inode_wait_for_writeback(inode);
|
2012-05-03 06:48:01 -06:00
|
|
|
|
2010-06-04 17:40:39 -06:00
|
|
|
if (op->evict_inode) {
|
|
|
|
op->evict_inode(inode);
|
2010-06-04 17:33:20 -06:00
|
|
|
} else {
|
|
|
|
if (inode->i_data.nrpages)
|
|
|
|
truncate_inode_pages(&inode->i_data, 0);
|
2012-05-03 06:48:02 -06:00
|
|
|
clear_inode(inode);
|
2010-06-04 17:33:20 -06:00
|
|
|
}
|
2010-06-04 18:19:55 -06:00
|
|
|
if (S_ISBLK(inode->i_mode) && inode->i_bdev)
|
|
|
|
bd_forget(inode);
|
|
|
|
if (S_ISCHR(inode->i_mode) && inode->i_cdev)
|
|
|
|
cd_forget(inode);
|
2011-03-22 05:23:37 -06:00
|
|
|
|
|
|
|
remove_inode_hash(inode);
|
|
|
|
|
|
|
|
spin_lock(&inode->i_lock);
|
|
|
|
wake_up_bit(&inode->i_state, __I_NEW);
|
|
|
|
BUG_ON(inode->i_state != (I_FREEING | I_CLEAR));
|
|
|
|
spin_unlock(&inode->i_lock);
|
|
|
|
|
|
|
|
destroy_inode(inode);
|
2010-06-04 17:33:20 -06:00
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/*
|
|
|
|
* dispose_list - dispose of the contents of a local list
|
|
|
|
* @head: the head of the list to free
|
|
|
|
*
|
|
|
|
* Dispose-list gets a local list with local inodes in it, so it doesn't
|
|
|
|
* need to worry about list corruption and SMP locks.
|
|
|
|
*/
|
|
|
|
static void dispose_list(struct list_head *head)
|
|
|
|
{
|
|
|
|
while (!list_empty(head)) {
|
|
|
|
struct inode *inode;
|
|
|
|
|
2010-10-20 18:49:30 -06:00
|
|
|
inode = list_first_entry(head, struct inode, i_lru);
|
|
|
|
list_del_init(&inode->i_lru);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2010-06-07 11:21:05 -06:00
|
|
|
evict(inode);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2010-10-25 18:49:35 -06:00
|
|
|
/**
|
|
|
|
* evict_inodes - evict all evictable inodes for a superblock
|
|
|
|
* @sb: superblock to operate on
|
|
|
|
*
|
|
|
|
* Make sure that no inodes with zero refcount are retained. This is
|
|
|
|
* called by superblock shutdown after having MS_ACTIVE flag removed,
|
|
|
|
* so any inode reaching zero refcount during or after that call will
|
|
|
|
* be immediately evicted.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2010-10-25 18:49:35 -06:00
|
|
|
void evict_inodes(struct super_block *sb)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2010-10-25 18:49:35 -06:00
|
|
|
struct inode *inode, *next;
|
|
|
|
LIST_HEAD(dispose);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-22 05:23:40 -06:00
|
|
|
spin_lock(&inode_sb_list_lock);
|
2010-10-25 18:49:35 -06:00
|
|
|
list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) {
|
|
|
|
if (atomic_read(&inode->i_count))
|
2009-03-11 14:17:36 -06:00
|
|
|
continue;
|
2011-03-22 05:23:36 -06:00
|
|
|
|
|
|
|
spin_lock(&inode->i_lock);
|
|
|
|
if (inode->i_state & (I_NEW | I_FREEING | I_WILL_FREE)) {
|
|
|
|
spin_unlock(&inode->i_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
continue;
|
2011-03-22 05:23:36 -06:00
|
|
|
}
|
2010-10-25 18:49:35 -06:00
|
|
|
|
|
|
|
inode->i_state |= I_FREEING;
|
2011-03-22 05:23:38 -06:00
|
|
|
inode_lru_list_del(inode);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-03-22 05:23:38 -06:00
|
|
|
list_add(&inode->i_lru, &dispose);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2011-03-22 05:23:40 -06:00
|
|
|
spin_unlock(&inode_sb_list_lock);
|
2010-10-25 18:49:35 -06:00
|
|
|
|
|
|
|
dispose_list(&dispose);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
2010-10-24 11:40:33 -06:00
|
|
|
* invalidate_inodes - attempt to free all inodes on a superblock
|
|
|
|
* @sb: superblock to operate on
|
2011-02-23 23:25:47 -07:00
|
|
|
* @kill_dirty: flag to guide handling of dirty inodes
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2010-10-24 11:40:33 -06:00
|
|
|
* Attempts to free all inodes for a given superblock. If there were any
|
|
|
|
* busy inodes return a non-zero value, else zero.
|
2011-02-23 23:25:47 -07:00
|
|
|
* If @kill_dirty is set, discard dirty inodes too, otherwise treat
|
|
|
|
* them as busy.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2011-02-23 23:25:47 -07:00
|
|
|
int invalidate_inodes(struct super_block *sb, bool kill_dirty)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2010-10-23 03:03:02 -06:00
|
|
|
int busy = 0;
|
2010-10-24 11:40:33 -06:00
|
|
|
struct inode *inode, *next;
|
|
|
|
LIST_HEAD(dispose);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-22 05:23:40 -06:00
|
|
|
spin_lock(&inode_sb_list_lock);
|
2010-10-24 11:40:33 -06:00
|
|
|
list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) {
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
|
|
|
if (inode->i_state & (I_NEW | I_FREEING | I_WILL_FREE)) {
|
|
|
|
spin_unlock(&inode->i_lock);
|
2009-03-11 14:17:36 -06:00
|
|
|
continue;
|
2011-03-22 05:23:36 -06:00
|
|
|
}
|
2011-02-23 23:25:47 -07:00
|
|
|
if (inode->i_state & I_DIRTY && !kill_dirty) {
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-02-23 23:25:47 -07:00
|
|
|
busy = 1;
|
|
|
|
continue;
|
|
|
|
}
|
2010-10-23 11:07:20 -06:00
|
|
|
if (atomic_read(&inode->i_count)) {
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2010-10-23 11:07:20 -06:00
|
|
|
busy = 1;
|
2005-04-16 16:20:36 -06:00
|
|
|
continue;
|
|
|
|
}
|
2010-10-23 11:07:20 -06:00
|
|
|
|
|
|
|
inode->i_state |= I_FREEING;
|
2011-03-22 05:23:38 -06:00
|
|
|
inode_lru_list_del(inode);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-03-22 05:23:38 -06:00
|
|
|
list_add(&inode->i_lru, &dispose);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2011-03-22 05:23:40 -06:00
|
|
|
spin_unlock(&inode_sb_list_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2010-10-24 11:40:33 -06:00
|
|
|
dispose_list(&dispose);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
return busy;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int can_unuse(struct inode *inode)
|
|
|
|
{
|
2010-10-23 04:55:17 -06:00
|
|
|
if (inode->i_state & ~I_REFERENCED)
|
2005-04-16 16:20:36 -06:00
|
|
|
return 0;
|
|
|
|
if (inode_has_buffers(inode))
|
|
|
|
return 0;
|
|
|
|
if (atomic_read(&inode->i_count))
|
|
|
|
return 0;
|
|
|
|
if (inode->i_data.nrpages)
|
|
|
|
return 0;
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
2011-07-07 22:14:42 -06:00
|
|
|
* Walk the superblock inode LRU for freeable inodes and attempt to free them.
|
|
|
|
* This is called from the superblock shrinker function with a number of inodes
|
|
|
|
* to trim from the LRU. Inodes to be freed are moved to a temporary list and
|
|
|
|
* then are freed outside inode_lock by dispose_list().
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
|
|
|
* Any inodes which are pinned purely because of attached pagecache have their
|
2010-10-23 04:55:17 -06:00
|
|
|
* pagecache removed. If the inode has metadata buffers attached to
|
|
|
|
* mapping->private_list then try to remove them.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2010-10-23 04:55:17 -06:00
|
|
|
* If the inode has the I_REFERENCED flag set, then it means that it has been
|
|
|
|
* used recently - the flag is set in iput_final(). When we encounter such an
|
|
|
|
* inode, clear the flag and move it to the back of the LRU so it gets another
|
|
|
|
* pass through the LRU before it gets reclaimed. This is necessary because of
|
|
|
|
* the fact we are doing lazy LRU updates to minimise lock contention so the
|
|
|
|
* LRU does not have strict ordering. Hence we don't want to reclaim inodes
|
|
|
|
* with this flag set because they are the inodes that are out of order.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2011-07-07 22:14:42 -06:00
|
|
|
void prune_icache_sb(struct super_block *sb, int nr_to_scan)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
LIST_HEAD(freeable);
|
|
|
|
int nr_scanned;
|
|
|
|
unsigned long reap = 0;
|
|
|
|
|
2011-07-07 22:14:40 -06:00
|
|
|
spin_lock(&sb->s_inode_lru_lock);
|
2011-07-07 22:14:42 -06:00
|
|
|
for (nr_scanned = nr_to_scan; nr_scanned >= 0; nr_scanned--) {
|
2005-04-16 16:20:36 -06:00
|
|
|
struct inode *inode;
|
|
|
|
|
2011-07-07 22:14:39 -06:00
|
|
|
if (list_empty(&sb->s_inode_lru))
|
2005-04-16 16:20:36 -06:00
|
|
|
break;
|
|
|
|
|
2011-07-07 22:14:39 -06:00
|
|
|
inode = list_entry(sb->s_inode_lru.prev, struct inode, i_lru);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-22 05:23:38 -06:00
|
|
|
/*
|
2011-07-07 22:14:40 -06:00
|
|
|
* we are inverting the sb->s_inode_lru_lock/inode->i_lock here,
|
2011-03-22 05:23:38 -06:00
|
|
|
* so use a trylock. If we fail to get the lock, just move the
|
|
|
|
* inode to the back of the list so we don't spin on it.
|
|
|
|
*/
|
|
|
|
if (!spin_trylock(&inode->i_lock)) {
|
2011-10-28 02:03:41 -06:00
|
|
|
list_move_tail(&inode->i_lru, &sb->s_inode_lru);
|
2011-03-22 05:23:38 -06:00
|
|
|
continue;
|
|
|
|
}
|
|
|
|
|
2010-10-23 04:55:17 -06:00
|
|
|
/*
|
|
|
|
* Referenced or dirty inodes are still in use. Give them
|
|
|
|
* another pass through the LRU as we canot reclaim them now.
|
|
|
|
*/
|
|
|
|
if (atomic_read(&inode->i_count) ||
|
|
|
|
(inode->i_state & ~I_REFERENCED)) {
|
2010-10-20 18:49:30 -06:00
|
|
|
list_del_init(&inode->i_lru);
|
2011-03-22 05:23:39 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-07-07 22:14:39 -06:00
|
|
|
sb->s_nr_inodes_unused--;
|
2011-07-07 22:14:38 -06:00
|
|
|
this_cpu_dec(nr_unused);
|
2010-10-23 04:55:17 -06:00
|
|
|
continue;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* recently referenced inodes get one more pass */
|
|
|
|
if (inode->i_state & I_REFERENCED) {
|
|
|
|
inode->i_state &= ~I_REFERENCED;
|
2011-07-07 22:14:39 -06:00
|
|
|
list_move(&inode->i_lru, &sb->s_inode_lru);
|
2011-03-22 05:23:39 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
continue;
|
|
|
|
}
|
|
|
|
if (inode_has_buffers(inode) || inode->i_data.nrpages) {
|
|
|
|
__iget(inode);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-07-07 22:14:40 -06:00
|
|
|
spin_unlock(&sb->s_inode_lru_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
if (remove_inode_buffers(inode))
|
2007-02-10 02:45:39 -07:00
|
|
|
reap += invalidate_mapping_pages(&inode->i_data,
|
|
|
|
0, -1);
|
2005-04-16 16:20:36 -06:00
|
|
|
iput(inode);
|
2011-07-07 22:14:40 -06:00
|
|
|
spin_lock(&sb->s_inode_lru_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-07-07 22:14:39 -06:00
|
|
|
if (inode != list_entry(sb->s_inode_lru.next,
|
2010-10-20 18:49:30 -06:00
|
|
|
struct inode, i_lru))
|
2005-04-16 16:20:36 -06:00
|
|
|
continue; /* wrong inode or list_empty */
|
2011-03-22 05:23:38 -06:00
|
|
|
/* avoid lock inversions with trylock */
|
|
|
|
if (!spin_trylock(&inode->i_lock))
|
|
|
|
continue;
|
2011-03-22 05:23:36 -06:00
|
|
|
if (!can_unuse(inode)) {
|
|
|
|
spin_unlock(&inode->i_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
continue;
|
2011-03-22 05:23:36 -06:00
|
|
|
}
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
fs: new inode i_state corruption fix
There was a report of a data corruption
http://lkml.org/lkml/2008/11/14/121. There is a script included to
reproduce the problem.
During testing, I encountered a number of strange things with ext3, so I
tried ext2 to attempt to reduce complexity of the problem. I found that
fsstress would quickly hang in wait_on_inode, waiting for I_LOCK to be
cleared, even though instrumentation showed that unlock_new_inode had
already been called for that inode. This points to memory scribble, or
synchronisation problme.
i_state of I_NEW inodes is not protected by inode_lock because other
processes are not supposed to touch them until I_LOCK (and I_NEW) is
cleared. Adding WARN_ON(inode->i_state & I_NEW) to sites where we modify
i_state revealed that generic_sync_sb_inodes is picking up new inodes from
the inode lists and passing them to __writeback_single_inode without
waiting for I_NEW. Subsequently modifying i_state causes corruption. In
my case it would look like this:
CPU0 CPU1
unlock_new_inode() __sync_single_inode()
reg <- inode->i_state
reg -> reg & ~(I_LOCK|I_NEW) reg <- inode->i_state
reg -> inode->i_state reg -> reg | I_SYNC
reg -> inode->i_state
Non-atomic RMW on CPU1 overwrites CPU0 store and sets I_LOCK|I_NEW again.
Fix for this is rather than wait for I_NEW inodes, just skip over them:
inodes concurrently being created are not subject to data integrity
operations, and should not significantly contribute to dirty memory
either.
After this change, I'm unable to reproduce any of the added warnings or
hangs after ~1hour of running. Previously, the new warnings would start
immediately and hang would happen in under 5 minutes.
I'm also testing on ext3 now, and so far no problems there either. I
don't know whether this fixes the problem reported above, but it fixes a
real problem for me.
Cc: "Jorge Boncompte [DTI2]" <jorge@dti2.net>
Reported-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Cc: Jan Kara <jack@suse.cz>
Cc: <stable@kernel.org>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-12 15:31:38 -06:00
|
|
|
WARN_ON(inode->i_state & I_NEW);
|
2005-04-16 16:20:36 -06:00
|
|
|
inode->i_state |= I_FREEING;
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2010-10-20 18:49:30 -06:00
|
|
|
|
|
|
|
list_move(&inode->i_lru, &freeable);
|
2011-07-07 22:14:39 -06:00
|
|
|
sb->s_nr_inodes_unused--;
|
2011-07-07 22:14:38 -06:00
|
|
|
this_cpu_dec(nr_unused);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2006-06-30 02:55:45 -06:00
|
|
|
if (current_is_kswapd())
|
|
|
|
__count_vm_events(KSWAPD_INODESTEAL, reap);
|
|
|
|
else
|
|
|
|
__count_vm_events(PGINODESTEAL, reap);
|
2011-07-07 22:14:40 -06:00
|
|
|
spin_unlock(&sb->s_inode_lru_lock);
|
2012-01-10 16:07:18 -07:00
|
|
|
if (current->reclaim_state)
|
|
|
|
current->reclaim_state->reclaimed_slab += reap;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
dispose_list(&freeable);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void __wait_on_freeing_inode(struct inode *inode);
|
|
|
|
/*
|
|
|
|
* Called with the inode lock held.
|
|
|
|
*/
|
2009-03-31 08:05:54 -06:00
|
|
|
static struct inode *find_inode(struct super_block *sb,
|
|
|
|
struct hlist_head *head,
|
|
|
|
int (*test)(struct inode *, void *),
|
|
|
|
void *data)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
struct hlist_node *node;
|
2009-03-31 08:05:54 -06:00
|
|
|
struct inode *inode = NULL;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
repeat:
|
2008-04-29 01:59:40 -06:00
|
|
|
hlist_for_each_entry(inode, node, head, i_hash) {
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
|
|
|
if (inode->i_sb != sb) {
|
|
|
|
spin_unlock(&inode->i_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
continue;
|
2011-03-22 05:23:42 -06:00
|
|
|
}
|
|
|
|
if (!test(inode, data)) {
|
|
|
|
spin_unlock(&inode->i_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
continue;
|
2011-03-22 05:23:42 -06:00
|
|
|
}
|
2010-06-02 15:38:30 -06:00
|
|
|
if (inode->i_state & (I_FREEING|I_WILL_FREE)) {
|
2005-04-16 16:20:36 -06:00
|
|
|
__wait_on_freeing_inode(inode);
|
|
|
|
goto repeat;
|
|
|
|
}
|
2010-10-23 05:09:06 -06:00
|
|
|
__iget(inode);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2010-10-23 05:09:06 -06:00
|
|
|
return inode;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2010-10-23 05:09:06 -06:00
|
|
|
return NULL;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* find_inode_fast is the fast path version of find_inode, see the comment at
|
|
|
|
* iget_locked for details.
|
|
|
|
*/
|
2009-03-31 08:05:54 -06:00
|
|
|
static struct inode *find_inode_fast(struct super_block *sb,
|
|
|
|
struct hlist_head *head, unsigned long ino)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
struct hlist_node *node;
|
2009-03-31 08:05:54 -06:00
|
|
|
struct inode *inode = NULL;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
repeat:
|
2008-04-29 01:59:40 -06:00
|
|
|
hlist_for_each_entry(inode, node, head, i_hash) {
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
|
|
|
if (inode->i_ino != ino) {
|
|
|
|
spin_unlock(&inode->i_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
continue;
|
2011-03-22 05:23:42 -06:00
|
|
|
}
|
|
|
|
if (inode->i_sb != sb) {
|
|
|
|
spin_unlock(&inode->i_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
continue;
|
2011-03-22 05:23:42 -06:00
|
|
|
}
|
2010-06-02 15:38:30 -06:00
|
|
|
if (inode->i_state & (I_FREEING|I_WILL_FREE)) {
|
2005-04-16 16:20:36 -06:00
|
|
|
__wait_on_freeing_inode(inode);
|
|
|
|
goto repeat;
|
|
|
|
}
|
2010-10-23 05:09:06 -06:00
|
|
|
__iget(inode);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2010-10-23 05:09:06 -06:00
|
|
|
return inode;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2010-10-23 05:09:06 -06:00
|
|
|
return NULL;
|
2008-10-30 00:35:24 -06:00
|
|
|
}
|
|
|
|
|
2010-10-23 09:18:01 -06:00
|
|
|
/*
|
|
|
|
* Each cpu owns a range of LAST_INO_BATCH numbers.
|
|
|
|
* 'shared_last_ino' is dirtied only once out of LAST_INO_BATCH allocations,
|
|
|
|
* to renew the exhausted range.
|
2008-10-30 00:35:24 -06:00
|
|
|
*
|
2010-10-23 09:18:01 -06:00
|
|
|
* This does not significantly increase overflow rate because every CPU can
|
|
|
|
* consume at most LAST_INO_BATCH-1 unused inode numbers. So there is
|
|
|
|
* NR_CPUS*(LAST_INO_BATCH-1) wastage. At 4096 and 1024, this is ~0.1% of the
|
|
|
|
* 2^32 range, and is a worst-case. Even a 50% wastage would only increase
|
|
|
|
* overflow rate by 2x, which does not seem too significant.
|
|
|
|
*
|
|
|
|
* On a 32bit, non LFS stat() call, glibc will generate an EOVERFLOW
|
|
|
|
* error if st_ino won't fit in target struct field. Use 32bit counter
|
|
|
|
* here to attempt to avoid that.
|
2008-10-30 00:35:24 -06:00
|
|
|
*/
|
2010-10-23 09:18:01 -06:00
|
|
|
#define LAST_INO_BATCH 1024
|
|
|
|
static DEFINE_PER_CPU(unsigned int, last_ino);
|
|
|
|
|
2010-10-23 09:19:54 -06:00
|
|
|
unsigned int get_next_ino(void)
|
2008-10-30 00:35:24 -06:00
|
|
|
{
|
2010-10-23 09:18:01 -06:00
|
|
|
unsigned int *p = &get_cpu_var(last_ino);
|
|
|
|
unsigned int res = *p;
|
2008-10-30 00:35:24 -06:00
|
|
|
|
2010-10-23 09:18:01 -06:00
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
if (unlikely((res & (LAST_INO_BATCH-1)) == 0)) {
|
|
|
|
static atomic_t shared_last_ino;
|
|
|
|
int next = atomic_add_return(LAST_INO_BATCH, &shared_last_ino);
|
|
|
|
|
|
|
|
res = next - LAST_INO_BATCH;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
*p = ++res;
|
|
|
|
put_cpu_var(last_ino);
|
|
|
|
return res;
|
2008-10-30 00:35:24 -06:00
|
|
|
}
|
2010-10-23 09:19:54 -06:00
|
|
|
EXPORT_SYMBOL(get_next_ino);
|
2008-10-30 00:35:24 -06:00
|
|
|
|
2011-07-26 03:36:34 -06:00
|
|
|
/**
|
|
|
|
* new_inode_pseudo - obtain an inode
|
|
|
|
* @sb: superblock
|
|
|
|
*
|
|
|
|
* Allocates a new inode for given superblock.
|
|
|
|
* Inode wont be chained in superblock s_inodes list
|
|
|
|
* This means :
|
|
|
|
* - fs can't be unmount
|
|
|
|
* - quotas, fsnotify, writeback can't work
|
|
|
|
*/
|
|
|
|
struct inode *new_inode_pseudo(struct super_block *sb)
|
|
|
|
{
|
|
|
|
struct inode *inode = alloc_inode(sb);
|
|
|
|
|
|
|
|
if (inode) {
|
|
|
|
spin_lock(&inode->i_lock);
|
|
|
|
inode->i_state = 0;
|
|
|
|
spin_unlock(&inode->i_lock);
|
|
|
|
INIT_LIST_HEAD(&inode->i_sb_list);
|
|
|
|
}
|
|
|
|
return inode;
|
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
|
|
|
* new_inode - obtain an inode
|
|
|
|
* @sb: superblock
|
|
|
|
*
|
2007-07-17 05:03:05 -06:00
|
|
|
* Allocates a new inode for given superblock. The default gfp_mask
|
2009-01-06 15:39:23 -07:00
|
|
|
* for allocations related to inode->i_mapping is GFP_HIGHUSER_MOVABLE.
|
2007-07-17 05:03:05 -06:00
|
|
|
* If HIGHMEM pages are unsuitable or it is known that pages allocated
|
|
|
|
* for the page cache are not reclaimable or migratable,
|
|
|
|
* mapping_set_gfp_mask() must be called with suitable flags on the
|
|
|
|
* newly created inode's mapping
|
|
|
|
*
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
|
|
|
struct inode *new_inode(struct super_block *sb)
|
|
|
|
{
|
2009-03-31 08:05:54 -06:00
|
|
|
struct inode *inode;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-22 05:23:40 -06:00
|
|
|
spin_lock_prefetch(&inode_sb_list_lock);
|
2009-03-31 08:05:54 -06:00
|
|
|
|
2011-07-26 03:36:34 -06:00
|
|
|
inode = new_inode_pseudo(sb);
|
|
|
|
if (inode)
|
2011-03-22 05:23:40 -06:00
|
|
|
inode_sb_list_add(inode);
|
2005-04-16 16:20:36 -06:00
|
|
|
return inode;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(new_inode);
|
|
|
|
|
2007-10-13 17:38:33 -06:00
|
|
|
#ifdef CONFIG_DEBUG_LOCK_ALLOC
|
lockdep: Add helper function for dir vs file i_mutex annotation
Purely in-memory filesystems do not use the inode hash as the dcache
tells us if an entry already exists. As a result, they do not call
unlock_new_inode, and thus directory inodes do not get put into a
different lockdep class for i_sem.
We need the different lockdep classes, because the locking order for
i_mutex is different for directory inodes and regular inodes. Directory
inodes can do "readdir()", which takes i_mutex *before* possibly taking
mm->mmap_sem (due to a page fault while copying the directory entry to
user space).
In contrast, regular inodes can be mmap'ed, which takes mm->mmap_sem
before accessing i_mutex.
The two cases can never happen for the same inode, so no real deadlock
can occur, but without the different lockdep classes, lockdep cannot
understand that. As a result, if CONFIG_DEBUG_LOCK_ALLOC is set, this
can lead to false positives from lockdep like below:
find/645 is trying to acquire lock:
(&mm->mmap_sem){++++++}, at: [<ffffffff81109514>] might_fault+0x5c/0xac
but task is already holding lock:
(&sb->s_type->i_mutex_key#15){+.+.+.}, at: [<ffffffff81149f34>]
vfs_readdir+0x5b/0xb4
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&sb->s_type->i_mutex_key#15){+.+.+.}:
[<ffffffff8108ac26>] lock_acquire+0xbf/0x103
[<ffffffff814db822>] __mutex_lock_common+0x4c/0x361
[<ffffffff814dbc46>] mutex_lock_nested+0x40/0x45
[<ffffffff811daa87>] hugetlbfs_file_mmap+0x82/0x110
[<ffffffff81111557>] mmap_region+0x258/0x432
[<ffffffff811119dd>] do_mmap_pgoff+0x2ac/0x306
[<ffffffff81111b4f>] sys_mmap_pgoff+0x118/0x16a
[<ffffffff8100c858>] sys_mmap+0x22/0x24
[<ffffffff814e3ec2>] system_call_fastpath+0x16/0x1b
-> #0 (&mm->mmap_sem){++++++}:
[<ffffffff8108a4bc>] __lock_acquire+0xa1a/0xcf7
[<ffffffff8108ac26>] lock_acquire+0xbf/0x103
[<ffffffff81109541>] might_fault+0x89/0xac
[<ffffffff81149cff>] filldir+0x6f/0xc7
[<ffffffff811586ea>] dcache_readdir+0x67/0x205
[<ffffffff81149f54>] vfs_readdir+0x7b/0xb4
[<ffffffff8114a073>] sys_getdents+0x7e/0xd1
[<ffffffff814e3ec2>] system_call_fastpath+0x16/0x1b
This patch moves the directory vs file lockdep annotation into a helper
function that can be called by in-memory filesystems and has hugetlbfs
call it.
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-25 05:48:12 -06:00
|
|
|
void lockdep_annotate_inode_mutex_key(struct inode *inode)
|
|
|
|
{
|
2010-10-11 07:38:00 -06:00
|
|
|
if (S_ISDIR(inode->i_mode)) {
|
2007-10-15 22:47:54 -06:00
|
|
|
struct file_system_type *type = inode->i_sb->s_type;
|
|
|
|
|
2009-06-04 07:26:49 -06:00
|
|
|
/* Set new key only if filesystem hasn't already changed it */
|
2011-12-12 09:02:30 -07:00
|
|
|
if (lockdep_match_class(&inode->i_mutex, &type->i_mutex_key)) {
|
2009-06-04 07:26:49 -06:00
|
|
|
/*
|
|
|
|
* ensure nobody is actually holding i_mutex
|
|
|
|
*/
|
|
|
|
mutex_destroy(&inode->i_mutex);
|
|
|
|
mutex_init(&inode->i_mutex);
|
|
|
|
lockdep_set_class(&inode->i_mutex,
|
|
|
|
&type->i_mutex_dir_key);
|
|
|
|
}
|
2007-10-15 22:47:54 -06:00
|
|
|
}
|
lockdep: Add helper function for dir vs file i_mutex annotation
Purely in-memory filesystems do not use the inode hash as the dcache
tells us if an entry already exists. As a result, they do not call
unlock_new_inode, and thus directory inodes do not get put into a
different lockdep class for i_sem.
We need the different lockdep classes, because the locking order for
i_mutex is different for directory inodes and regular inodes. Directory
inodes can do "readdir()", which takes i_mutex *before* possibly taking
mm->mmap_sem (due to a page fault while copying the directory entry to
user space).
In contrast, regular inodes can be mmap'ed, which takes mm->mmap_sem
before accessing i_mutex.
The two cases can never happen for the same inode, so no real deadlock
can occur, but without the different lockdep classes, lockdep cannot
understand that. As a result, if CONFIG_DEBUG_LOCK_ALLOC is set, this
can lead to false positives from lockdep like below:
find/645 is trying to acquire lock:
(&mm->mmap_sem){++++++}, at: [<ffffffff81109514>] might_fault+0x5c/0xac
but task is already holding lock:
(&sb->s_type->i_mutex_key#15){+.+.+.}, at: [<ffffffff81149f34>]
vfs_readdir+0x5b/0xb4
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&sb->s_type->i_mutex_key#15){+.+.+.}:
[<ffffffff8108ac26>] lock_acquire+0xbf/0x103
[<ffffffff814db822>] __mutex_lock_common+0x4c/0x361
[<ffffffff814dbc46>] mutex_lock_nested+0x40/0x45
[<ffffffff811daa87>] hugetlbfs_file_mmap+0x82/0x110
[<ffffffff81111557>] mmap_region+0x258/0x432
[<ffffffff811119dd>] do_mmap_pgoff+0x2ac/0x306
[<ffffffff81111b4f>] sys_mmap_pgoff+0x118/0x16a
[<ffffffff8100c858>] sys_mmap+0x22/0x24
[<ffffffff814e3ec2>] system_call_fastpath+0x16/0x1b
-> #0 (&mm->mmap_sem){++++++}:
[<ffffffff8108a4bc>] __lock_acquire+0xa1a/0xcf7
[<ffffffff8108ac26>] lock_acquire+0xbf/0x103
[<ffffffff81109541>] might_fault+0x89/0xac
[<ffffffff81149cff>] filldir+0x6f/0xc7
[<ffffffff811586ea>] dcache_readdir+0x67/0x205
[<ffffffff81149f54>] vfs_readdir+0x7b/0xb4
[<ffffffff8114a073>] sys_getdents+0x7e/0xd1
[<ffffffff814e3ec2>] system_call_fastpath+0x16/0x1b
This patch moves the directory vs file lockdep annotation into a helper
function that can be called by in-memory filesystems and has hugetlbfs
call it.
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-25 05:48:12 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(lockdep_annotate_inode_mutex_key);
|
2007-10-13 17:38:33 -06:00
|
|
|
#endif
|
lockdep: Add helper function for dir vs file i_mutex annotation
Purely in-memory filesystems do not use the inode hash as the dcache
tells us if an entry already exists. As a result, they do not call
unlock_new_inode, and thus directory inodes do not get put into a
different lockdep class for i_sem.
We need the different lockdep classes, because the locking order for
i_mutex is different for directory inodes and regular inodes. Directory
inodes can do "readdir()", which takes i_mutex *before* possibly taking
mm->mmap_sem (due to a page fault while copying the directory entry to
user space).
In contrast, regular inodes can be mmap'ed, which takes mm->mmap_sem
before accessing i_mutex.
The two cases can never happen for the same inode, so no real deadlock
can occur, but without the different lockdep classes, lockdep cannot
understand that. As a result, if CONFIG_DEBUG_LOCK_ALLOC is set, this
can lead to false positives from lockdep like below:
find/645 is trying to acquire lock:
(&mm->mmap_sem){++++++}, at: [<ffffffff81109514>] might_fault+0x5c/0xac
but task is already holding lock:
(&sb->s_type->i_mutex_key#15){+.+.+.}, at: [<ffffffff81149f34>]
vfs_readdir+0x5b/0xb4
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&sb->s_type->i_mutex_key#15){+.+.+.}:
[<ffffffff8108ac26>] lock_acquire+0xbf/0x103
[<ffffffff814db822>] __mutex_lock_common+0x4c/0x361
[<ffffffff814dbc46>] mutex_lock_nested+0x40/0x45
[<ffffffff811daa87>] hugetlbfs_file_mmap+0x82/0x110
[<ffffffff81111557>] mmap_region+0x258/0x432
[<ffffffff811119dd>] do_mmap_pgoff+0x2ac/0x306
[<ffffffff81111b4f>] sys_mmap_pgoff+0x118/0x16a
[<ffffffff8100c858>] sys_mmap+0x22/0x24
[<ffffffff814e3ec2>] system_call_fastpath+0x16/0x1b
-> #0 (&mm->mmap_sem){++++++}:
[<ffffffff8108a4bc>] __lock_acquire+0xa1a/0xcf7
[<ffffffff8108ac26>] lock_acquire+0xbf/0x103
[<ffffffff81109541>] might_fault+0x89/0xac
[<ffffffff81149cff>] filldir+0x6f/0xc7
[<ffffffff811586ea>] dcache_readdir+0x67/0x205
[<ffffffff81149f54>] vfs_readdir+0x7b/0xb4
[<ffffffff8114a073>] sys_getdents+0x7e/0xd1
[<ffffffff814e3ec2>] system_call_fastpath+0x16/0x1b
This patch moves the directory vs file lockdep annotation into a helper
function that can be called by in-memory filesystems and has hugetlbfs
call it.
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-25 05:48:12 -06:00
|
|
|
|
|
|
|
/**
|
|
|
|
* unlock_new_inode - clear the I_NEW state and wake up any waiters
|
|
|
|
* @inode: new inode to unlock
|
|
|
|
*
|
|
|
|
* Called when the inode is fully initialised to clear the new state of the
|
|
|
|
* inode and wake up anyone waiting for the inode to finish initialisation.
|
|
|
|
*/
|
|
|
|
void unlock_new_inode(struct inode *inode)
|
|
|
|
{
|
|
|
|
lockdep_annotate_inode_mutex_key(inode);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
2009-12-17 06:25:01 -07:00
|
|
|
WARN_ON(!(inode->i_state & I_NEW));
|
|
|
|
inode->i_state &= ~I_NEW;
|
2012-03-10 15:07:28 -07:00
|
|
|
smp_mb();
|
2011-03-22 05:23:36 -06:00
|
|
|
wake_up_bit(&inode->i_state, __I_NEW);
|
|
|
|
spin_unlock(&inode->i_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(unlock_new_inode);
|
|
|
|
|
2011-03-23 13:03:28 -06:00
|
|
|
/**
|
|
|
|
* iget5_locked - obtain an inode from a mounted file system
|
|
|
|
* @sb: super block of file system
|
|
|
|
* @hashval: hash value (usually inode number) to get
|
|
|
|
* @test: callback used for comparisons between inodes
|
|
|
|
* @set: callback used to initialize a new struct inode
|
|
|
|
* @data: opaque data pointer to pass to @test and @set
|
|
|
|
*
|
|
|
|
* Search for the inode specified by @hashval and @data in the inode cache,
|
|
|
|
* and if present it is return it with an increased reference count. This is
|
|
|
|
* a generalized version of iget_locked() for file systems where the inode
|
|
|
|
* number is not sufficient for unique identification of an inode.
|
|
|
|
*
|
|
|
|
* If the inode is not in cache, allocate a new inode and return it locked,
|
|
|
|
* hashed, and with the I_NEW flag set. The file system gets to fill it in
|
|
|
|
* before unlocking it via unlock_new_inode().
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2011-03-23 13:03:28 -06:00
|
|
|
* Note both @test and @set are called with the inode_hash_lock held, so can't
|
|
|
|
* sleep.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2011-03-23 13:03:28 -06:00
|
|
|
struct inode *iget5_locked(struct super_block *sb, unsigned long hashval,
|
|
|
|
int (*test)(struct inode *, void *),
|
|
|
|
int (*set)(struct inode *, void *), void *data)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2011-03-23 13:03:28 -06:00
|
|
|
struct hlist_head *head = inode_hashtable + hash(sb, hashval);
|
2009-03-31 08:05:54 -06:00
|
|
|
struct inode *inode;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-23 13:03:28 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
|
|
|
inode = find_inode(sb, head, test, data);
|
|
|
|
spin_unlock(&inode_hash_lock);
|
|
|
|
|
|
|
|
if (inode) {
|
|
|
|
wait_on_inode(inode);
|
|
|
|
return inode;
|
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
inode = alloc_inode(sb);
|
|
|
|
if (inode) {
|
2009-03-31 08:05:54 -06:00
|
|
|
struct inode *old;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
/* We released the lock, so.. */
|
|
|
|
old = find_inode(sb, head, test, data);
|
|
|
|
if (!old) {
|
|
|
|
if (set(inode, data))
|
|
|
|
goto set_failed;
|
|
|
|
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
|
|
|
inode->i_state = I_NEW;
|
2010-10-23 05:15:32 -06:00
|
|
|
hlist_add_head(&inode->i_hash, head);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-03-22 05:23:40 -06:00
|
|
|
inode_sb_list_add(inode);
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/* Return the locked inode with I_NEW set, the
|
|
|
|
* caller is responsible for filling in the contents
|
|
|
|
*/
|
|
|
|
return inode;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Uhhuh, somebody else created the same inode under
|
|
|
|
* us. Use the old inode instead of the one we just
|
|
|
|
* allocated.
|
|
|
|
*/
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
destroy_inode(inode);
|
|
|
|
inode = old;
|
|
|
|
wait_on_inode(inode);
|
|
|
|
}
|
|
|
|
return inode;
|
|
|
|
|
|
|
|
set_failed:
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
destroy_inode(inode);
|
|
|
|
return NULL;
|
|
|
|
}
|
2011-03-23 13:03:28 -06:00
|
|
|
EXPORT_SYMBOL(iget5_locked);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-23 13:03:28 -06:00
|
|
|
/**
|
|
|
|
* iget_locked - obtain an inode from a mounted file system
|
|
|
|
* @sb: super block of file system
|
|
|
|
* @ino: inode number to get
|
|
|
|
*
|
|
|
|
* Search for the inode specified by @ino in the inode cache and if present
|
|
|
|
* return it with an increased reference count. This is for file systems
|
|
|
|
* where the inode number is sufficient for unique identification of an inode.
|
|
|
|
*
|
|
|
|
* If the inode is not in cache, allocate a new inode and return it locked,
|
|
|
|
* hashed, and with the I_NEW flag set. The file system gets to fill it in
|
|
|
|
* before unlocking it via unlock_new_inode().
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2011-03-23 13:03:28 -06:00
|
|
|
struct inode *iget_locked(struct super_block *sb, unsigned long ino)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2011-03-23 13:03:28 -06:00
|
|
|
struct hlist_head *head = inode_hashtable + hash(sb, ino);
|
2009-03-31 08:05:54 -06:00
|
|
|
struct inode *inode;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-23 13:03:28 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
|
|
|
inode = find_inode_fast(sb, head, ino);
|
|
|
|
spin_unlock(&inode_hash_lock);
|
|
|
|
if (inode) {
|
|
|
|
wait_on_inode(inode);
|
|
|
|
return inode;
|
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
inode = alloc_inode(sb);
|
|
|
|
if (inode) {
|
2009-03-31 08:05:54 -06:00
|
|
|
struct inode *old;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
/* We released the lock, so.. */
|
|
|
|
old = find_inode_fast(sb, head, ino);
|
|
|
|
if (!old) {
|
|
|
|
inode->i_ino = ino;
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
|
|
|
inode->i_state = I_NEW;
|
2010-10-23 05:15:32 -06:00
|
|
|
hlist_add_head(&inode->i_hash, head);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-03-22 05:23:40 -06:00
|
|
|
inode_sb_list_add(inode);
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/* Return the locked inode with I_NEW set, the
|
|
|
|
* caller is responsible for filling in the contents
|
|
|
|
*/
|
|
|
|
return inode;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Uhhuh, somebody else created the same inode under
|
|
|
|
* us. Use the old inode instead of the one we just
|
|
|
|
* allocated.
|
|
|
|
*/
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
destroy_inode(inode);
|
|
|
|
inode = old;
|
|
|
|
wait_on_inode(inode);
|
|
|
|
}
|
|
|
|
return inode;
|
|
|
|
}
|
2011-03-23 13:03:28 -06:00
|
|
|
EXPORT_SYMBOL(iget_locked);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2010-10-23 05:00:16 -06:00
|
|
|
/*
|
|
|
|
* search the inode cache for a matching inode number.
|
|
|
|
* If we find one, then the inode number we are trying to
|
|
|
|
* allocate is not unique and so we should not use it.
|
|
|
|
*
|
|
|
|
* Returns 1 if the inode number is unique, 0 if it is not.
|
|
|
|
*/
|
|
|
|
static int test_inode_iunique(struct super_block *sb, unsigned long ino)
|
|
|
|
{
|
|
|
|
struct hlist_head *b = inode_hashtable + hash(sb, ino);
|
|
|
|
struct hlist_node *node;
|
|
|
|
struct inode *inode;
|
|
|
|
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
2010-10-23 05:00:16 -06:00
|
|
|
hlist_for_each_entry(inode, node, b, i_hash) {
|
2011-03-22 05:23:42 -06:00
|
|
|
if (inode->i_ino == ino && inode->i_sb == sb) {
|
|
|
|
spin_unlock(&inode_hash_lock);
|
2010-10-23 05:00:16 -06:00
|
|
|
return 0;
|
2011-03-22 05:23:42 -06:00
|
|
|
}
|
2010-10-23 05:00:16 -06:00
|
|
|
}
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2010-10-23 05:00:16 -06:00
|
|
|
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
|
|
|
* iunique - get a unique inode number
|
|
|
|
* @sb: superblock
|
|
|
|
* @max_reserved: highest reserved inode number
|
|
|
|
*
|
|
|
|
* Obtain an inode number that is unique on the system for a given
|
|
|
|
* superblock. This is used by file systems that have no natural
|
|
|
|
* permanent inode numbering system. An inode number is returned that
|
|
|
|
* is higher than the reserved limit but unique.
|
|
|
|
*
|
|
|
|
* BUGS:
|
|
|
|
* With a large number of inodes live on the file system this function
|
|
|
|
* currently becomes quite slow.
|
|
|
|
*/
|
|
|
|
ino_t iunique(struct super_block *sb, ino_t max_reserved)
|
|
|
|
{
|
inode numbering: make static counters in new_inode and iunique be 32 bits
The problems are:
- on filesystems w/o permanent inode numbers, i_ino values can be larger
than 32 bits, which can cause problems for some 32 bit userspace programs on
a 64 bit kernel. We can't do anything for filesystems that have actual
>32-bit inode numbers, but on filesystems that generate i_ino values on the
fly, we should try to have them fit in 32 bits. We could trivially fix this
by making the static counters in new_inode and iunique 32 bits, but...
- many filesystems call new_inode and assume that the i_ino values they are
given are unique. They are not guaranteed to be so, since the static
counter can wrap. This problem is exacerbated by the fix for #1.
- after allocating a new inode, some filesystems call iunique to try to get
a unique i_ino value, but they don't actually add their inodes to the
hashtable, and so they're still not guaranteed to be unique if that counter
wraps.
This patch set takes the simpler approach of simply using iunique and hashing
the inodes afterward. Christoph H. previously mentioned that he thought that
this approach may slow down lookups for filesystems that currently hash their
inodes.
The questions are:
1) how much would this slow down lookups for these filesystems?
2) is it enough to justify adding more infrastructure to avoid it?
What might be best is to start with this approach and then only move to using
IDR or some other scheme if these extra inodes in the hashtable prove to be
problematic.
I've done some cursory testing with this patch and the overhead of hashing and
unhashing the inodes with pipefs is pretty low -- just a few seconds of system
time added on to the creation and destruction of 10 million pipes (very
similar to the overhead that the IDR approach would add).
The hard thing to measure is what effect this has on other filesystems. I'm
open to ways to try and gauge this.
Again, I've only converted pipefs as an example. If this approach is
acceptable then I'll start work on patches to convert other filesystems.
With a pretty-much-worst-case microbenchmark provided by Eric Dumazet
<dada1@cosmosbay.com>:
hashing patch (pipebench):
sys 1m15.329s
sys 1m16.249s
sys 1m17.169s
unpatched (pipebench):
sys 1m9.836s
sys 1m12.541s
sys 1m14.153s
Which works out to 1.05642174294555027017. So ~5-6% slowdown.
This patch:
When a 32-bit program that was not compiled with large file offsets does a
stat and gets a st_ino value back that won't fit in the 32 bit field, glibc
(correctly) generates an EOVERFLOW error. We can't do anything about fs's
with larger permanent inode numbers, but when we generate them on the fly, we
ought to try and have them fit within a 32 bit field.
This patch takes the first step toward this by making the static counters in
these two functions be 32 bits.
[jlayton@redhat.com: mention that it's only the case for 32bit, non-LFS stat]
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 01:32:29 -06:00
|
|
|
/*
|
|
|
|
* On a 32bit, non LFS stat() call, glibc will generate an EOVERFLOW
|
|
|
|
* error if st_ino won't fit in target struct field. Use 32bit counter
|
|
|
|
* here to attempt to avoid that.
|
|
|
|
*/
|
2010-10-23 05:00:16 -06:00
|
|
|
static DEFINE_SPINLOCK(iunique_lock);
|
inode numbering: make static counters in new_inode and iunique be 32 bits
The problems are:
- on filesystems w/o permanent inode numbers, i_ino values can be larger
than 32 bits, which can cause problems for some 32 bit userspace programs on
a 64 bit kernel. We can't do anything for filesystems that have actual
>32-bit inode numbers, but on filesystems that generate i_ino values on the
fly, we should try to have them fit in 32 bits. We could trivially fix this
by making the static counters in new_inode and iunique 32 bits, but...
- many filesystems call new_inode and assume that the i_ino values they are
given are unique. They are not guaranteed to be so, since the static
counter can wrap. This problem is exacerbated by the fix for #1.
- after allocating a new inode, some filesystems call iunique to try to get
a unique i_ino value, but they don't actually add their inodes to the
hashtable, and so they're still not guaranteed to be unique if that counter
wraps.
This patch set takes the simpler approach of simply using iunique and hashing
the inodes afterward. Christoph H. previously mentioned that he thought that
this approach may slow down lookups for filesystems that currently hash their
inodes.
The questions are:
1) how much would this slow down lookups for these filesystems?
2) is it enough to justify adding more infrastructure to avoid it?
What might be best is to start with this approach and then only move to using
IDR or some other scheme if these extra inodes in the hashtable prove to be
problematic.
I've done some cursory testing with this patch and the overhead of hashing and
unhashing the inodes with pipefs is pretty low -- just a few seconds of system
time added on to the creation and destruction of 10 million pipes (very
similar to the overhead that the IDR approach would add).
The hard thing to measure is what effect this has on other filesystems. I'm
open to ways to try and gauge this.
Again, I've only converted pipefs as an example. If this approach is
acceptable then I'll start work on patches to convert other filesystems.
With a pretty-much-worst-case microbenchmark provided by Eric Dumazet
<dada1@cosmosbay.com>:
hashing patch (pipebench):
sys 1m15.329s
sys 1m16.249s
sys 1m17.169s
unpatched (pipebench):
sys 1m9.836s
sys 1m12.541s
sys 1m14.153s
Which works out to 1.05642174294555027017. So ~5-6% slowdown.
This patch:
When a 32-bit program that was not compiled with large file offsets does a
stat and gets a st_ino value back that won't fit in the 32 bit field, glibc
(correctly) generates an EOVERFLOW error. We can't do anything about fs's
with larger permanent inode numbers, but when we generate them on the fly, we
ought to try and have them fit within a 32 bit field.
This patch takes the first step toward this by making the static counters in
these two functions be 32 bits.
[jlayton@redhat.com: mention that it's only the case for 32bit, non-LFS stat]
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 01:32:29 -06:00
|
|
|
static unsigned int counter;
|
2005-04-16 16:20:36 -06:00
|
|
|
ino_t res;
|
2007-05-08 01:29:48 -06:00
|
|
|
|
2010-10-23 05:00:16 -06:00
|
|
|
spin_lock(&iunique_lock);
|
2007-05-08 01:29:48 -06:00
|
|
|
do {
|
|
|
|
if (counter <= max_reserved)
|
|
|
|
counter = max_reserved + 1;
|
2005-04-16 16:20:36 -06:00
|
|
|
res = counter++;
|
2010-10-23 05:00:16 -06:00
|
|
|
} while (!test_inode_iunique(sb, res));
|
|
|
|
spin_unlock(&iunique_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2007-05-08 01:29:48 -06:00
|
|
|
return res;
|
|
|
|
}
|
2005-04-16 16:20:36 -06:00
|
|
|
EXPORT_SYMBOL(iunique);
|
|
|
|
|
|
|
|
struct inode *igrab(struct inode *inode)
|
|
|
|
{
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
|
|
|
if (!(inode->i_state & (I_FREEING|I_WILL_FREE))) {
|
2005-04-16 16:20:36 -06:00
|
|
|
__iget(inode);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
|
|
|
} else {
|
|
|
|
spin_unlock(&inode->i_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
/*
|
|
|
|
* Handle the case where s_op->clear_inode is not been
|
|
|
|
* called yet, and somebody is calling igrab
|
|
|
|
* while the inode is getting freed.
|
|
|
|
*/
|
|
|
|
inode = NULL;
|
2011-03-22 05:23:36 -06:00
|
|
|
}
|
2005-04-16 16:20:36 -06:00
|
|
|
return inode;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(igrab);
|
|
|
|
|
|
|
|
/**
|
2011-03-23 13:03:28 -06:00
|
|
|
* ilookup5_nowait - search for an inode in the inode cache
|
2005-04-16 16:20:36 -06:00
|
|
|
* @sb: super block of file system to search
|
2011-03-23 13:03:28 -06:00
|
|
|
* @hashval: hash value (usually inode number) to search for
|
2005-04-16 16:20:36 -06:00
|
|
|
* @test: callback used for comparisons between inodes
|
|
|
|
* @data: opaque data pointer to pass to @test
|
|
|
|
*
|
2011-03-23 13:03:28 -06:00
|
|
|
* Search for the inode specified by @hashval and @data in the inode cache.
|
2005-04-16 16:20:36 -06:00
|
|
|
* If the inode is in the cache, the inode is returned with an incremented
|
|
|
|
* reference count.
|
|
|
|
*
|
2011-03-23 13:03:28 -06:00
|
|
|
* Note: I_NEW is not waited upon so you have to be very careful what you do
|
|
|
|
* with the returned inode. You probably should be using ilookup5() instead.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2011-03-26 14:27:47 -06:00
|
|
|
* Note2: @test is called with the inode_hash_lock held, so can't sleep.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2011-03-23 13:03:28 -06:00
|
|
|
struct inode *ilookup5_nowait(struct super_block *sb, unsigned long hashval,
|
|
|
|
int (*test)(struct inode *, void *), void *data)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2011-03-23 13:03:28 -06:00
|
|
|
struct hlist_head *head = inode_hashtable + hash(sb, hashval);
|
2005-04-16 16:20:36 -06:00
|
|
|
struct inode *inode;
|
|
|
|
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
inode = find_inode(sb, head, test, data);
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2005-07-13 02:10:44 -06:00
|
|
|
|
2011-03-23 13:03:28 -06:00
|
|
|
return inode;
|
2005-07-13 02:10:44 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(ilookup5_nowait);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* ilookup5 - search for an inode in the inode cache
|
|
|
|
* @sb: super block of file system to search
|
|
|
|
* @hashval: hash value (usually inode number) to search for
|
|
|
|
* @test: callback used for comparisons between inodes
|
|
|
|
* @data: opaque data pointer to pass to @test
|
|
|
|
*
|
2011-03-23 13:03:28 -06:00
|
|
|
* Search for the inode specified by @hashval and @data in the inode cache,
|
|
|
|
* and if the inode is in the cache, return the inode with an incremented
|
|
|
|
* reference count. Waits on I_NEW before returning the inode.
|
2005-07-13 02:10:44 -06:00
|
|
|
* returned with an incremented reference count.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2011-03-23 13:03:28 -06:00
|
|
|
* This is a generalized version of ilookup() for file systems where the
|
|
|
|
* inode number is not sufficient for unique identification of an inode.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2011-03-23 13:03:28 -06:00
|
|
|
* Note: @test is called with the inode_hash_lock held, so can't sleep.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
|
|
|
struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
|
|
|
|
int (*test)(struct inode *, void *), void *data)
|
|
|
|
{
|
2011-03-23 13:03:28 -06:00
|
|
|
struct inode *inode = ilookup5_nowait(sb, hashval, test, data);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-23 13:03:28 -06:00
|
|
|
if (inode)
|
|
|
|
wait_on_inode(inode);
|
|
|
|
return inode;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(ilookup5);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* ilookup - search for an inode in the inode cache
|
|
|
|
* @sb: super block of file system to search
|
|
|
|
* @ino: inode number to search for
|
|
|
|
*
|
2011-03-23 13:03:28 -06:00
|
|
|
* Search for the inode @ino in the inode cache, and if the inode is in the
|
|
|
|
* cache, the inode is returned with an incremented reference count.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
|
|
|
struct inode *ilookup(struct super_block *sb, unsigned long ino)
|
|
|
|
{
|
|
|
|
struct hlist_head *head = inode_hashtable + hash(sb, ino);
|
|
|
|
struct inode *inode;
|
|
|
|
|
2011-03-23 13:03:28 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
|
|
|
inode = find_inode_fast(sb, head, ino);
|
|
|
|
spin_unlock(&inode_hash_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
if (inode)
|
2011-03-23 13:03:28 -06:00
|
|
|
wait_on_inode(inode);
|
|
|
|
return inode;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2011-03-23 13:03:28 -06:00
|
|
|
EXPORT_SYMBOL(ilookup);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2008-12-29 23:48:21 -07:00
|
|
|
int insert_inode_locked(struct inode *inode)
|
|
|
|
{
|
|
|
|
struct super_block *sb = inode->i_sb;
|
|
|
|
ino_t ino = inode->i_ino;
|
|
|
|
struct hlist_head *head = inode_hashtable + hash(sb, ino);
|
|
|
|
|
|
|
|
while (1) {
|
2009-05-13 12:13:40 -06:00
|
|
|
struct hlist_node *node;
|
|
|
|
struct inode *old = NULL;
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
2009-05-13 12:13:40 -06:00
|
|
|
hlist_for_each_entry(old, node, head, i_hash) {
|
|
|
|
if (old->i_ino != ino)
|
|
|
|
continue;
|
|
|
|
if (old->i_sb != sb)
|
|
|
|
continue;
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&old->i_lock);
|
|
|
|
if (old->i_state & (I_FREEING|I_WILL_FREE)) {
|
|
|
|
spin_unlock(&old->i_lock);
|
2009-05-13 12:13:40 -06:00
|
|
|
continue;
|
2011-03-22 05:23:36 -06:00
|
|
|
}
|
2009-05-13 12:13:40 -06:00
|
|
|
break;
|
|
|
|
}
|
|
|
|
if (likely(!node)) {
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
|
|
|
inode->i_state |= I_NEW;
|
2008-12-29 23:48:21 -07:00
|
|
|
hlist_add_head(&inode->i_hash, head);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2008-12-29 23:48:21 -07:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
__iget(old);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&old->i_lock);
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2008-12-29 23:48:21 -07:00
|
|
|
wait_on_inode(old);
|
2010-10-23 13:19:20 -06:00
|
|
|
if (unlikely(!inode_unhashed(old))) {
|
2008-12-29 23:48:21 -07:00
|
|
|
iput(old);
|
|
|
|
return -EBUSY;
|
|
|
|
}
|
|
|
|
iput(old);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(insert_inode_locked);
|
|
|
|
|
|
|
|
int insert_inode_locked4(struct inode *inode, unsigned long hashval,
|
|
|
|
int (*test)(struct inode *, void *), void *data)
|
|
|
|
{
|
|
|
|
struct super_block *sb = inode->i_sb;
|
|
|
|
struct hlist_head *head = inode_hashtable + hash(sb, hashval);
|
|
|
|
|
|
|
|
while (1) {
|
2009-05-13 12:13:40 -06:00
|
|
|
struct hlist_node *node;
|
|
|
|
struct inode *old = NULL;
|
|
|
|
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
2009-05-13 12:13:40 -06:00
|
|
|
hlist_for_each_entry(old, node, head, i_hash) {
|
|
|
|
if (old->i_sb != sb)
|
|
|
|
continue;
|
|
|
|
if (!test(old, data))
|
|
|
|
continue;
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&old->i_lock);
|
|
|
|
if (old->i_state & (I_FREEING|I_WILL_FREE)) {
|
|
|
|
spin_unlock(&old->i_lock);
|
2009-05-13 12:13:40 -06:00
|
|
|
continue;
|
2011-03-22 05:23:36 -06:00
|
|
|
}
|
2009-05-13 12:13:40 -06:00
|
|
|
break;
|
|
|
|
}
|
|
|
|
if (likely(!node)) {
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
|
|
|
inode->i_state |= I_NEW;
|
2008-12-29 23:48:21 -07:00
|
|
|
hlist_add_head(&inode->i_hash, head);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2008-12-29 23:48:21 -07:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
__iget(old);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&old->i_lock);
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2008-12-29 23:48:21 -07:00
|
|
|
wait_on_inode(old);
|
2010-10-23 13:19:20 -06:00
|
|
|
if (unlikely(!inode_unhashed(old))) {
|
2008-12-29 23:48:21 -07:00
|
|
|
iput(old);
|
|
|
|
return -EBUSY;
|
|
|
|
}
|
|
|
|
iput(old);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(insert_inode_locked4);
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2010-06-07 11:43:19 -06:00
|
|
|
int generic_delete_inode(struct inode *inode)
|
|
|
|
{
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(generic_delete_inode);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Called when we're dropping the last reference
|
|
|
|
* to an inode.
|
2009-09-18 14:05:44 -06:00
|
|
|
*
|
2010-06-07 11:43:19 -06:00
|
|
|
* Call the FS "drop_inode()" function, defaulting to
|
|
|
|
* the legacy UNIX filesystem behaviour. If it tells
|
|
|
|
* us to evict inode, do so. Otherwise, retain inode
|
|
|
|
* in cache if fs is alive, sync and evict if fs is
|
|
|
|
* shutting down.
|
2009-09-18 14:05:44 -06:00
|
|
|
*/
|
2010-06-07 11:43:19 -06:00
|
|
|
static void iput_final(struct inode *inode)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
struct super_block *sb = inode->i_sb;
|
2010-06-07 11:43:19 -06:00
|
|
|
const struct super_operations *op = inode->i_sb->s_op;
|
|
|
|
int drop;
|
|
|
|
|
2011-03-22 05:23:36 -06:00
|
|
|
WARN_ON(inode->i_state & I_NEW);
|
|
|
|
|
2011-07-07 13:45:59 -06:00
|
|
|
if (op->drop_inode)
|
2010-06-07 11:43:19 -06:00
|
|
|
drop = op->drop_inode(inode);
|
|
|
|
else
|
|
|
|
drop = generic_drop_inode(inode);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-22 05:23:37 -06:00
|
|
|
if (!drop && (sb->s_flags & MS_ACTIVE)) {
|
|
|
|
inode->i_state |= I_REFERENCED;
|
|
|
|
if (!(inode->i_state & (I_DIRTY|I_SYNC)))
|
|
|
|
inode_lru_list_add(inode);
|
|
|
|
spin_unlock(&inode->i_lock);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
2010-06-07 11:43:19 -06:00
|
|
|
if (!drop) {
|
2005-06-23 01:09:01 -06:00
|
|
|
inode->i_state |= I_WILL_FREE;
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
write_inode_now(inode, 1);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_lock(&inode->i_lock);
|
fs: new inode i_state corruption fix
There was a report of a data corruption
http://lkml.org/lkml/2008/11/14/121. There is a script included to
reproduce the problem.
During testing, I encountered a number of strange things with ext3, so I
tried ext2 to attempt to reduce complexity of the problem. I found that
fsstress would quickly hang in wait_on_inode, waiting for I_LOCK to be
cleared, even though instrumentation showed that unlock_new_inode had
already been called for that inode. This points to memory scribble, or
synchronisation problme.
i_state of I_NEW inodes is not protected by inode_lock because other
processes are not supposed to touch them until I_LOCK (and I_NEW) is
cleared. Adding WARN_ON(inode->i_state & I_NEW) to sites where we modify
i_state revealed that generic_sync_sb_inodes is picking up new inodes from
the inode lists and passing them to __writeback_single_inode without
waiting for I_NEW. Subsequently modifying i_state causes corruption. In
my case it would look like this:
CPU0 CPU1
unlock_new_inode() __sync_single_inode()
reg <- inode->i_state
reg -> reg & ~(I_LOCK|I_NEW) reg <- inode->i_state
reg -> inode->i_state reg -> reg | I_SYNC
reg -> inode->i_state
Non-atomic RMW on CPU1 overwrites CPU0 store and sets I_LOCK|I_NEW again.
Fix for this is rather than wait for I_NEW inodes, just skip over them:
inodes concurrently being created are not subject to data integrity
operations, and should not significantly contribute to dirty memory
either.
After this change, I'm unable to reproduce any of the added warnings or
hangs after ~1hour of running. Previously, the new warnings would start
immediately and hang would happen in under 5 minutes.
I'm also testing on ext3 now, and so far no problems there either. I
don't know whether this fixes the problem reported above, but it fixes a
real problem for me.
Cc: "Jorge Boncompte [DTI2]" <jorge@dti2.net>
Reported-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Cc: Jan Kara <jack@suse.cz>
Cc: <stable@kernel.org>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-12 15:31:38 -06:00
|
|
|
WARN_ON(inode->i_state & I_NEW);
|
2005-06-23 01:09:01 -06:00
|
|
|
inode->i_state &= ~I_WILL_FREE;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2010-10-20 18:49:30 -06:00
|
|
|
|
2005-06-23 01:09:01 -06:00
|
|
|
inode->i_state |= I_FREEING;
|
2011-07-27 22:55:13 -06:00
|
|
|
if (!list_empty(&inode->i_lru))
|
|
|
|
inode_lru_list_del(inode);
|
2011-03-22 05:23:37 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
|
|
|
|
2010-06-07 11:21:05 -06:00
|
|
|
evict(inode);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
2009-03-31 08:05:54 -06:00
|
|
|
* iput - put an inode
|
2005-04-16 16:20:36 -06:00
|
|
|
* @inode: inode to put
|
|
|
|
*
|
|
|
|
* Puts an inode, dropping its usage count. If the inode use count hits
|
|
|
|
* zero, the inode is then freed and may also be destroyed.
|
|
|
|
*
|
|
|
|
* Consequently, iput() can sleep.
|
|
|
|
*/
|
|
|
|
void iput(struct inode *inode)
|
|
|
|
{
|
|
|
|
if (inode) {
|
2010-06-02 15:38:30 -06:00
|
|
|
BUG_ON(inode->i_state & I_CLEAR);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2011-03-22 05:23:39 -06:00
|
|
|
if (atomic_dec_and_lock(&inode->i_count, &inode->i_lock))
|
2005-04-16 16:20:36 -06:00
|
|
|
iput_final(inode);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(iput);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* bmap - find a block number in a file
|
|
|
|
* @inode: inode of file
|
|
|
|
* @block: block to find
|
|
|
|
*
|
|
|
|
* Returns the block number on the device holding the inode that
|
|
|
|
* is the disk block number for the block of the file requested.
|
|
|
|
* That is, asked for block 4 of inode 1 the function will return the
|
2009-03-31 08:05:54 -06:00
|
|
|
* disk block relative to the disk start that holds that block of the
|
2005-04-16 16:20:36 -06:00
|
|
|
* file.
|
|
|
|
*/
|
2009-03-31 08:05:54 -06:00
|
|
|
sector_t bmap(struct inode *inode, sector_t block)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
sector_t res = 0;
|
|
|
|
if (inode->i_mapping->a_ops->bmap)
|
|
|
|
res = inode->i_mapping->a_ops->bmap(inode->i_mapping, block);
|
|
|
|
return res;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(bmap);
|
|
|
|
|
2009-03-26 11:32:14 -06:00
|
|
|
/*
|
|
|
|
* With relative atime, only update atime if the previous atime is
|
|
|
|
* earlier than either the ctime or mtime or if at least a day has
|
|
|
|
* passed since the last atime update.
|
|
|
|
*/
|
|
|
|
static int relatime_need_update(struct vfsmount *mnt, struct inode *inode,
|
|
|
|
struct timespec now)
|
|
|
|
{
|
|
|
|
|
|
|
|
if (!(mnt->mnt_flags & MNT_RELATIME))
|
|
|
|
return 1;
|
|
|
|
/*
|
|
|
|
* Is mtime younger than atime? If yes, update atime:
|
|
|
|
*/
|
|
|
|
if (timespec_compare(&inode->i_mtime, &inode->i_atime) >= 0)
|
|
|
|
return 1;
|
|
|
|
/*
|
|
|
|
* Is ctime younger than atime? If yes, update atime:
|
|
|
|
*/
|
|
|
|
if (timespec_compare(&inode->i_ctime, &inode->i_atime) >= 0)
|
|
|
|
return 1;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Is the previous atime value older than a day? If yes,
|
|
|
|
* update atime:
|
|
|
|
*/
|
|
|
|
if ((long)(now.tv_sec - inode->i_atime.tv_sec) >= 24*60*60)
|
|
|
|
return 1;
|
|
|
|
/*
|
|
|
|
* Good, we can skip the atime update:
|
|
|
|
*/
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2012-03-26 07:59:21 -06:00
|
|
|
/*
|
|
|
|
* This does the actual work of updating an inodes time or version. Must have
|
|
|
|
* had called mnt_want_write() before calling this.
|
|
|
|
*/
|
|
|
|
static int update_time(struct inode *inode, struct timespec *time, int flags)
|
|
|
|
{
|
|
|
|
if (inode->i_op->update_time)
|
|
|
|
return inode->i_op->update_time(inode, time, flags);
|
|
|
|
|
|
|
|
if (flags & S_ATIME)
|
|
|
|
inode->i_atime = *time;
|
|
|
|
if (flags & S_VERSION)
|
|
|
|
inode_inc_iversion(inode);
|
|
|
|
if (flags & S_CTIME)
|
|
|
|
inode->i_ctime = *time;
|
|
|
|
if (flags & S_MTIME)
|
|
|
|
inode->i_mtime = *time;
|
|
|
|
mark_inode_dirty_sync(inode);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
2006-01-09 21:52:03 -07:00
|
|
|
* touch_atime - update the access time
|
2012-04-17 18:03:25 -06:00
|
|
|
* @path: the &struct path to update
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
|
|
|
* Update the accessed time on an inode and mark it for writeback.
|
|
|
|
* This function automatically handles read only file systems and media,
|
|
|
|
* as well as the "noatime" flag and inode specific "noatime" markers.
|
|
|
|
*/
|
2012-03-15 06:21:57 -06:00
|
|
|
void touch_atime(struct path *path)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2012-03-15 06:21:57 -06:00
|
|
|
struct vfsmount *mnt = path->mnt;
|
|
|
|
struct inode *inode = path->dentry->d_inode;
|
2005-04-16 16:20:36 -06:00
|
|
|
struct timespec now;
|
|
|
|
|
2008-02-15 15:37:41 -07:00
|
|
|
if (inode->i_flags & S_NOATIME)
|
2009-09-18 14:05:47 -06:00
|
|
|
return;
|
2007-02-10 02:44:49 -07:00
|
|
|
if (IS_NOATIME(inode))
|
2009-09-18 14:05:47 -06:00
|
|
|
return;
|
2006-12-13 01:34:33 -07:00
|
|
|
if ((inode->i_sb->s_flags & MS_NODIRATIME) && S_ISDIR(inode->i_mode))
|
2009-09-18 14:05:47 -06:00
|
|
|
return;
|
2006-12-13 01:34:34 -07:00
|
|
|
|
2008-02-15 15:37:41 -07:00
|
|
|
if (mnt->mnt_flags & MNT_NOATIME)
|
2009-09-18 14:05:47 -06:00
|
|
|
return;
|
2008-02-15 15:37:41 -07:00
|
|
|
if ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode))
|
2009-09-18 14:05:47 -06:00
|
|
|
return;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
now = current_fs_time(inode->i_sb);
|
2009-03-26 11:32:14 -06:00
|
|
|
|
|
|
|
if (!relatime_need_update(mnt, inode, now))
|
2009-09-18 14:05:47 -06:00
|
|
|
return;
|
2009-03-26 11:32:14 -06:00
|
|
|
|
2006-12-13 01:34:34 -07:00
|
|
|
if (timespec_equal(&inode->i_atime, &now))
|
2009-09-18 14:05:47 -06:00
|
|
|
return;
|
|
|
|
|
2012-06-12 08:20:36 -06:00
|
|
|
if (!sb_start_write_trylock(inode->i_sb))
|
2009-09-18 14:05:47 -06:00
|
|
|
return;
|
2006-12-13 01:34:34 -07:00
|
|
|
|
2012-06-12 08:20:36 -06:00
|
|
|
if (__mnt_want_write(mnt))
|
|
|
|
goto skip_update;
|
2012-03-26 07:59:21 -06:00
|
|
|
/*
|
|
|
|
* File systems can error out when updating inodes if they need to
|
|
|
|
* allocate new space to modify an inode (such is the case for
|
|
|
|
* Btrfs), but since we touch atime while walking down the path we
|
|
|
|
* really don't care if we failed to update the atime of the file,
|
|
|
|
* so just ignore the return value.
|
2012-06-15 01:49:33 -06:00
|
|
|
* We may also fail on filesystems that have the ability to make parts
|
|
|
|
* of the fs read only, e.g. subvolumes in Btrfs.
|
2012-03-26 07:59:21 -06:00
|
|
|
*/
|
|
|
|
update_time(inode, &now, S_ATIME);
|
2012-06-12 08:20:36 -06:00
|
|
|
__mnt_drop_write(mnt);
|
|
|
|
skip_update:
|
|
|
|
sb_end_write(inode->i_sb);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2006-01-09 21:52:03 -07:00
|
|
|
EXPORT_SYMBOL(touch_atime);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2012-05-15 00:57:33 -06:00
|
|
|
/*
|
|
|
|
* The logic we want is
|
|
|
|
*
|
|
|
|
* if suid or (sgid and xgrp)
|
|
|
|
* remove privs
|
|
|
|
*/
|
|
|
|
int should_remove_suid(struct dentry *dentry)
|
|
|
|
{
|
|
|
|
umode_t mode = dentry->d_inode->i_mode;
|
|
|
|
int kill = 0;
|
|
|
|
|
|
|
|
/* suid always must be killed */
|
|
|
|
if (unlikely(mode & S_ISUID))
|
|
|
|
kill = ATTR_KILL_SUID;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* sgid without any exec bits is just a mandatory locking mark; leave
|
|
|
|
* it alone. If some exec bits are set, it's a real sgid; kill it.
|
|
|
|
*/
|
|
|
|
if (unlikely((mode & S_ISGID) && (mode & S_IXGRP)))
|
|
|
|
kill |= ATTR_KILL_SGID;
|
|
|
|
|
|
|
|
if (unlikely(kill && !capable(CAP_FSETID) && S_ISREG(mode)))
|
|
|
|
return kill;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(should_remove_suid);
|
|
|
|
|
|
|
|
static int __remove_suid(struct dentry *dentry, int kill)
|
|
|
|
{
|
|
|
|
struct iattr newattrs;
|
|
|
|
|
|
|
|
newattrs.ia_valid = ATTR_FORCE | kill;
|
|
|
|
return notify_change(dentry, &newattrs);
|
|
|
|
}
|
|
|
|
|
|
|
|
int file_remove_suid(struct file *file)
|
|
|
|
{
|
|
|
|
struct dentry *dentry = file->f_path.dentry;
|
|
|
|
struct inode *inode = dentry->d_inode;
|
|
|
|
int killsuid;
|
|
|
|
int killpriv;
|
|
|
|
int error = 0;
|
|
|
|
|
|
|
|
/* Fast path for nothing security related */
|
|
|
|
if (IS_NOSEC(inode))
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
killsuid = should_remove_suid(dentry);
|
|
|
|
killpriv = security_inode_need_killpriv(dentry);
|
|
|
|
|
|
|
|
if (killpriv < 0)
|
|
|
|
return killpriv;
|
|
|
|
if (killpriv)
|
|
|
|
error = security_inode_killpriv(dentry);
|
|
|
|
if (!error && killsuid)
|
|
|
|
error = __remove_suid(dentry, killsuid);
|
|
|
|
if (!error && (inode->i_sb->s_flags & MS_NOSEC))
|
|
|
|
inode->i_flags |= S_NOSEC;
|
|
|
|
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(file_remove_suid);
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
2006-01-09 21:52:01 -07:00
|
|
|
* file_update_time - update mtime and ctime time
|
|
|
|
* @file: file accessed
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2006-01-09 21:52:01 -07:00
|
|
|
* Update the mtime and ctime members of an inode and mark the inode
|
|
|
|
* for writeback. Note that this function is meant exclusively for
|
|
|
|
* usage in the file write path of filesystems, and filesystems may
|
|
|
|
* choose to explicitly ignore update via this function with the
|
2009-04-02 07:23:37 -06:00
|
|
|
* S_NOCMTIME inode flag, e.g. for network filesystem where these
|
2012-03-26 07:59:21 -06:00
|
|
|
* timestamps are handled by the server. This can return an error for
|
|
|
|
* file systems who need to allocate space in order to update an inode.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
|
|
|
|
2012-03-26 07:59:21 -06:00
|
|
|
int file_update_time(struct file *file)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2006-12-08 03:36:35 -07:00
|
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
2005-04-16 16:20:36 -06:00
|
|
|
struct timespec now;
|
2012-03-26 07:59:21 -06:00
|
|
|
int sync_it = 0;
|
|
|
|
int ret;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2009-09-18 14:05:48 -06:00
|
|
|
/* First try to exhaust all avenues to not sync */
|
2005-04-16 16:20:36 -06:00
|
|
|
if (IS_NOCMTIME(inode))
|
2012-03-26 07:59:21 -06:00
|
|
|
return 0;
|
2008-02-15 15:37:43 -07:00
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
now = current_fs_time(inode->i_sb);
|
2009-09-18 14:05:48 -06:00
|
|
|
if (!timespec_equal(&inode->i_mtime, &now))
|
|
|
|
sync_it = S_MTIME;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2009-09-18 14:05:48 -06:00
|
|
|
if (!timespec_equal(&inode->i_ctime, &now))
|
|
|
|
sync_it |= S_CTIME;
|
2006-01-09 21:52:01 -07:00
|
|
|
|
2009-09-18 14:05:48 -06:00
|
|
|
if (IS_I_VERSION(inode))
|
|
|
|
sync_it |= S_VERSION;
|
2008-01-28 21:58:27 -07:00
|
|
|
|
2009-09-18 14:05:48 -06:00
|
|
|
if (!sync_it)
|
2012-03-26 07:59:21 -06:00
|
|
|
return 0;
|
2009-09-18 14:05:48 -06:00
|
|
|
|
|
|
|
/* Finally allowed to write? Takes lock. */
|
2012-06-12 08:20:35 -06:00
|
|
|
if (__mnt_want_write_file(file))
|
2012-03-26 07:59:21 -06:00
|
|
|
return 0;
|
2009-09-18 14:05:48 -06:00
|
|
|
|
2012-03-26 07:59:21 -06:00
|
|
|
ret = update_time(inode, &now, sync_it);
|
2012-06-12 08:20:35 -06:00
|
|
|
__mnt_drop_write_file(file);
|
2012-03-26 07:59:21 -06:00
|
|
|
|
|
|
|
return ret;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2006-01-09 21:52:01 -07:00
|
|
|
EXPORT_SYMBOL(file_update_time);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
int inode_needs_sync(struct inode *inode)
|
|
|
|
{
|
|
|
|
if (IS_SYNC(inode))
|
|
|
|
return 1;
|
|
|
|
if (S_ISDIR(inode->i_mode) && IS_DIRSYNC(inode))
|
|
|
|
return 1;
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(inode_needs_sync);
|
|
|
|
|
|
|
|
int inode_wait(void *word)
|
|
|
|
{
|
|
|
|
schedule();
|
|
|
|
return 0;
|
|
|
|
}
|
2008-11-09 23:06:05 -07:00
|
|
|
EXPORT_SYMBOL(inode_wait);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/*
|
2005-07-12 14:58:10 -06:00
|
|
|
* If we try to find an inode in the inode hash while it is being
|
|
|
|
* deleted, we have to wait until the filesystem completes its
|
|
|
|
* deletion before reporting that it isn't found. This function waits
|
|
|
|
* until the deletion _might_ have completed. Callers are responsible
|
|
|
|
* to recheck inode state.
|
|
|
|
*
|
2009-12-17 06:25:01 -07:00
|
|
|
* It doesn't matter if I_NEW is not set initially, a call to
|
2011-03-22 05:23:36 -06:00
|
|
|
* wake_up_bit(&inode->i_state, __I_NEW) after removing from the hash list
|
|
|
|
* will DTRT.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
|
|
|
static void __wait_on_freeing_inode(struct inode *inode)
|
|
|
|
{
|
|
|
|
wait_queue_head_t *wq;
|
2009-12-17 06:25:01 -07:00
|
|
|
DEFINE_WAIT_BIT(wait, &inode->i_state, __I_NEW);
|
|
|
|
wq = bit_waitqueue(&inode->i_state, __I_NEW);
|
2005-04-16 16:20:36 -06:00
|
|
|
prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
|
2011-03-22 05:23:36 -06:00
|
|
|
spin_unlock(&inode->i_lock);
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_unlock(&inode_hash_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
schedule();
|
|
|
|
finish_wait(wq, &wait.wait);
|
2011-03-22 05:23:42 -06:00
|
|
|
spin_lock(&inode_hash_lock);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
static __initdata unsigned long ihash_entries;
|
|
|
|
static int __init set_ihash_entries(char *str)
|
|
|
|
{
|
|
|
|
if (!str)
|
|
|
|
return 0;
|
|
|
|
ihash_entries = simple_strtoul(str, &str, 0);
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
__setup("ihash_entries=", set_ihash_entries);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Initialize the waitqueues and inode hash table.
|
|
|
|
*/
|
|
|
|
void __init inode_init_early(void)
|
|
|
|
{
|
2012-02-08 13:39:07 -07:00
|
|
|
unsigned int loop;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/* If hashes are distributed across NUMA nodes, defer
|
|
|
|
* hash allocation until vmalloc space is available.
|
|
|
|
*/
|
|
|
|
if (hashdist)
|
|
|
|
return;
|
|
|
|
|
|
|
|
inode_hashtable =
|
|
|
|
alloc_large_system_hash("Inode-cache",
|
|
|
|
sizeof(struct hlist_head),
|
|
|
|
ihash_entries,
|
|
|
|
14,
|
|
|
|
HASH_EARLY,
|
|
|
|
&i_hash_shift,
|
|
|
|
&i_hash_mask,
|
2012-05-23 07:33:35 -06:00
|
|
|
0,
|
2005-04-16 16:20:36 -06:00
|
|
|
0);
|
|
|
|
|
2012-02-08 13:39:07 -07:00
|
|
|
for (loop = 0; loop < (1U << i_hash_shift); loop++)
|
2005-04-16 16:20:36 -06:00
|
|
|
INIT_HLIST_HEAD(&inode_hashtable[loop]);
|
|
|
|
}
|
|
|
|
|
2007-10-17 00:26:30 -06:00
|
|
|
void __init inode_init(void)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2012-02-08 13:39:07 -07:00
|
|
|
unsigned int loop;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/* inode slab cache */
|
2006-03-24 04:16:09 -07:00
|
|
|
inode_cachep = kmem_cache_create("inode_cache",
|
|
|
|
sizeof(struct inode),
|
|
|
|
0,
|
|
|
|
(SLAB_RECLAIM_ACCOUNT|SLAB_PANIC|
|
|
|
|
SLAB_MEM_SPREAD),
|
2007-07-19 19:11:58 -06:00
|
|
|
init_once);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/* Hash may have been set up in inode_init_early */
|
|
|
|
if (!hashdist)
|
|
|
|
return;
|
|
|
|
|
|
|
|
inode_hashtable =
|
|
|
|
alloc_large_system_hash("Inode-cache",
|
|
|
|
sizeof(struct hlist_head),
|
|
|
|
ihash_entries,
|
|
|
|
14,
|
|
|
|
0,
|
|
|
|
&i_hash_shift,
|
|
|
|
&i_hash_mask,
|
2012-05-23 07:33:35 -06:00
|
|
|
0,
|
2005-04-16 16:20:36 -06:00
|
|
|
0);
|
|
|
|
|
2012-02-08 13:39:07 -07:00
|
|
|
for (loop = 0; loop < (1U << i_hash_shift); loop++)
|
2005-04-16 16:20:36 -06:00
|
|
|
INIT_HLIST_HEAD(&inode_hashtable[loop]);
|
|
|
|
}
|
|
|
|
|
|
|
|
void init_special_inode(struct inode *inode, umode_t mode, dev_t rdev)
|
|
|
|
{
|
|
|
|
inode->i_mode = mode;
|
|
|
|
if (S_ISCHR(mode)) {
|
|
|
|
inode->i_fop = &def_chr_fops;
|
|
|
|
inode->i_rdev = rdev;
|
|
|
|
} else if (S_ISBLK(mode)) {
|
|
|
|
inode->i_fop = &def_blk_fops;
|
|
|
|
inode->i_rdev = rdev;
|
|
|
|
} else if (S_ISFIFO(mode))
|
|
|
|
inode->i_fop = &def_fifo_fops;
|
|
|
|
else if (S_ISSOCK(mode))
|
|
|
|
inode->i_fop = &bad_sock_fops;
|
|
|
|
else
|
2009-09-18 14:05:43 -06:00
|
|
|
printk(KERN_DEBUG "init_special_inode: bogus i_mode (%o) for"
|
|
|
|
" inode %s:%lu\n", mode, inode->i_sb->s_id,
|
|
|
|
inode->i_ino);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(init_special_inode);
|
2010-03-04 07:29:14 -07:00
|
|
|
|
|
|
|
/**
|
2011-02-15 05:48:09 -07:00
|
|
|
* inode_init_owner - Init uid,gid,mode for new inode according to posix standards
|
2010-03-04 07:29:14 -07:00
|
|
|
* @inode: New inode
|
|
|
|
* @dir: Directory inode
|
|
|
|
* @mode: mode of the new inode
|
|
|
|
*/
|
|
|
|
void inode_init_owner(struct inode *inode, const struct inode *dir,
|
2011-07-24 21:20:18 -06:00
|
|
|
umode_t mode)
|
2010-03-04 07:29:14 -07:00
|
|
|
{
|
|
|
|
inode->i_uid = current_fsuid();
|
|
|
|
if (dir && dir->i_mode & S_ISGID) {
|
|
|
|
inode->i_gid = dir->i_gid;
|
|
|
|
if (S_ISDIR(mode))
|
|
|
|
mode |= S_ISGID;
|
|
|
|
} else
|
|
|
|
inode->i_gid = current_fsgid();
|
|
|
|
inode->i_mode = mode;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(inode_init_owner);
|
2011-03-23 17:43:25 -06:00
|
|
|
|
2011-03-23 17:43:26 -06:00
|
|
|
/**
|
|
|
|
* inode_owner_or_capable - check current task permissions to inode
|
|
|
|
* @inode: inode being checked
|
|
|
|
*
|
|
|
|
* Return true if current either has CAP_FOWNER to the inode, or
|
|
|
|
* owns the file.
|
2011-03-23 17:43:25 -06:00
|
|
|
*/
|
2011-03-23 17:43:26 -06:00
|
|
|
bool inode_owner_or_capable(const struct inode *inode)
|
2011-03-23 17:43:25 -06:00
|
|
|
{
|
2012-02-08 08:07:50 -07:00
|
|
|
if (uid_eq(current_fsuid(), inode->i_uid))
|
2011-03-23 17:43:25 -06:00
|
|
|
return true;
|
2011-11-14 17:24:06 -07:00
|
|
|
if (inode_capable(inode, CAP_FOWNER))
|
2011-03-23 17:43:25 -06:00
|
|
|
return true;
|
|
|
|
return false;
|
|
|
|
}
|
2011-03-23 17:43:26 -06:00
|
|
|
EXPORT_SYMBOL(inode_owner_or_capable);
|
2012-05-31 10:22:33 -06:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Direct i/o helper functions
|
|
|
|
*/
|
|
|
|
static void __inode_dio_wait(struct inode *inode)
|
|
|
|
{
|
|
|
|
wait_queue_head_t *wq = bit_waitqueue(&inode->i_state, __I_DIO_WAKEUP);
|
|
|
|
DEFINE_WAIT_BIT(q, &inode->i_state, __I_DIO_WAKEUP);
|
|
|
|
|
|
|
|
do {
|
|
|
|
prepare_to_wait(wq, &q.wait, TASK_UNINTERRUPTIBLE);
|
|
|
|
if (atomic_read(&inode->i_dio_count))
|
|
|
|
schedule();
|
|
|
|
} while (atomic_read(&inode->i_dio_count));
|
|
|
|
finish_wait(wq, &q.wait);
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* inode_dio_wait - wait for outstanding DIO requests to finish
|
|
|
|
* @inode: inode to wait for
|
|
|
|
*
|
|
|
|
* Waits for all pending direct I/O requests to finish so that we can
|
|
|
|
* proceed with a truncate or equivalent operation.
|
|
|
|
*
|
|
|
|
* Must be called under a lock that serializes taking new references
|
|
|
|
* to i_dio_count, usually by inode->i_mutex.
|
|
|
|
*/
|
|
|
|
void inode_dio_wait(struct inode *inode)
|
|
|
|
{
|
|
|
|
if (atomic_read(&inode->i_dio_count))
|
|
|
|
__inode_dio_wait(inode);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(inode_dio_wait);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* inode_dio_done - signal finish of a direct I/O requests
|
|
|
|
* @inode: inode the direct I/O happens on
|
|
|
|
*
|
|
|
|
* This is called once we've finished processing a direct I/O request,
|
|
|
|
* and is used to wake up callers waiting for direct I/O to be quiesced.
|
|
|
|
*/
|
|
|
|
void inode_dio_done(struct inode *inode)
|
|
|
|
{
|
|
|
|
if (atomic_dec_and_test(&inode->i_dio_count))
|
|
|
|
wake_up_bit(&inode->i_state, __I_DIO_WAKEUP);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(inode_dio_done);
|