mm/fs: route MADV_REMOVE to FALLOC_FL_PUNCH_HOLE
Now tmpfs supports hole-punching via fallocate(), switch madvise_remove() to use do_fallocate() instead of vmtruncate_range(): which extends madvise(,,MADV_REMOVE) support from tmpfs to ext4, ocfs2 and xfs. There is one more user of vmtruncate_range() in our tree, staging/android's ashmem_shrink(): convert it to use do_fallocate() too (but if its unpinned areas are already unmapped - I don't know - then it would do better to use shmem_truncate_range() directly). Based-on-patch-by: Cong Wang <amwang@redhat.com> Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@android.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger@dilger.ca> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Ben Myers <bpm@sgi.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
83e4fa9c16
commit
3f31d07571
2 changed files with 12 additions and 11 deletions
|
@ -19,6 +19,7 @@
|
|||
#include <linux/module.h>
|
||||
#include <linux/file.h>
|
||||
#include <linux/fs.h>
|
||||
#include <linux/falloc.h>
|
||||
#include <linux/miscdevice.h>
|
||||
#include <linux/security.h>
|
||||
#include <linux/mm.h>
|
||||
|
@ -363,11 +364,12 @@ static int ashmem_shrink(struct shrinker *s, struct shrink_control *sc)
|
|||
|
||||
mutex_lock(&ashmem_mutex);
|
||||
list_for_each_entry_safe(range, next, &ashmem_lru_list, lru) {
|
||||
struct inode *inode = range->asma->file->f_dentry->d_inode;
|
||||
loff_t start = range->pgstart * PAGE_SIZE;
|
||||
loff_t end = (range->pgend + 1) * PAGE_SIZE - 1;
|
||||
loff_t end = (range->pgend + 1) * PAGE_SIZE;
|
||||
|
||||
vmtruncate_range(inode, start, end);
|
||||
do_fallocate(range->asma->file,
|
||||
FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
|
||||
start, end - start);
|
||||
range->purged = ASHMEM_WAS_PURGED;
|
||||
lru_del(range);
|
||||
|
||||
|
|
15
mm/madvise.c
15
mm/madvise.c
|
@ -11,8 +11,10 @@
|
|||
#include <linux/mempolicy.h>
|
||||
#include <linux/page-isolation.h>
|
||||
#include <linux/hugetlb.h>
|
||||
#include <linux/falloc.h>
|
||||
#include <linux/sched.h>
|
||||
#include <linux/ksm.h>
|
||||
#include <linux/fs.h>
|
||||
|
||||
/*
|
||||
* Any behaviour which results in changes to the vma->vm_flags needs to
|
||||
|
@ -200,8 +202,7 @@ static long madvise_remove(struct vm_area_struct *vma,
|
|||
struct vm_area_struct **prev,
|
||||
unsigned long start, unsigned long end)
|
||||
{
|
||||
struct address_space *mapping;
|
||||
loff_t offset, endoff;
|
||||
loff_t offset;
|
||||
int error;
|
||||
|
||||
*prev = NULL; /* tell sys_madvise we drop mmap_sem */
|
||||
|
@ -217,16 +218,14 @@ static long madvise_remove(struct vm_area_struct *vma,
|
|||
if ((vma->vm_flags & (VM_SHARED|VM_WRITE)) != (VM_SHARED|VM_WRITE))
|
||||
return -EACCES;
|
||||
|
||||
mapping = vma->vm_file->f_mapping;
|
||||
|
||||
offset = (loff_t)(start - vma->vm_start)
|
||||
+ ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
|
||||
endoff = (loff_t)(end - vma->vm_start - 1)
|
||||
+ ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
|
||||
|
||||
/* vmtruncate_range needs to take i_mutex */
|
||||
/* filesystem's fallocate may need to take i_mutex */
|
||||
up_read(¤t->mm->mmap_sem);
|
||||
error = vmtruncate_range(mapping->host, offset, endoff);
|
||||
error = do_fallocate(vma->vm_file,
|
||||
FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
|
||||
offset, end - start);
|
||||
down_read(¤t->mm->mmap_sem);
|
||||
return error;
|
||||
}
|
||||
|
|
Loading…
Reference in a new issue