kernel-fxtec-pro1x/include/linux/hugetlb.h
Hugh Dickins 68589bc353 [PATCH] hugetlb: prepare_hugepage_range check offset too
(David:)

If hugetlbfs_file_mmap() returns a failure to do_mmap_pgoff() - for example,
because the given file offset is not hugepage aligned - then do_mmap_pgoff
will go to the unmap_and_free_vma backout path.

But at this stage the vma hasn't been marked as hugepage, and the backout path
will call unmap_region() on it.  That will eventually call down to the
non-hugepage version of unmap_page_range().  On ppc64, at least, that will
cause serious problems if there are any existing hugepage pagetable entries in
the vicinity - for example if there are any other hugepage mappings under the
same PUD.  unmap_page_range() will trigger a bad_pud() on the hugepage pud
entries.  I suspect this will also cause bad problems on ia64, though I don't
have a machine to test it on.

(Hugh:)

prepare_hugepage_range() should check file offset alignment when it checks
virtual address and length, to stop MAP_FIXED with a bad huge offset from
unmapping before it fails further down.  PowerPC should apply the same
prepare_hugepage_range alignment checks as ia64 and all the others do.

Then none of the alignment checks in hugetlbfs_file_mmap are required (nor
is the check for too small a mapping); but even so, move up setting of
VM_HUGETLB and add a comment to warn of what David Gibson discovered - if
hugetlbfs_file_mmap fails before setting it, do_mmap_pgoff's unmap_region
when unwinding from error will go the non-huge way, which may cause bad
behaviour on architectures (powerpc and ia64) which segregate their huge
mappings into a separate region of the address space.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Adam Litke <agl@us.ibm.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-14 09:09:27 -08:00

185 lines
5.6 KiB
C

#ifndef _LINUX_HUGETLB_H
#define _LINUX_HUGETLB_H
#ifdef CONFIG_HUGETLB_PAGE
#include <linux/mempolicy.h>
#include <asm/tlbflush.h>
struct ctl_table;
static inline int is_vm_hugetlb_page(struct vm_area_struct *vma)
{
return vma->vm_flags & VM_HUGETLB;
}
int hugetlb_sysctl_handler(struct ctl_table *, int, struct file *, void __user *, size_t *, loff_t *);
int copy_hugetlb_page_range(struct mm_struct *, struct mm_struct *, struct vm_area_struct *);
int follow_hugetlb_page(struct mm_struct *, struct vm_area_struct *, struct page **, struct vm_area_struct **, unsigned long *, int *, int);
void unmap_hugepage_range(struct vm_area_struct *, unsigned long, unsigned long);
void __unmap_hugepage_range(struct vm_area_struct *, unsigned long, unsigned long);
int hugetlb_prefault(struct address_space *, struct vm_area_struct *);
int hugetlb_report_meminfo(char *);
int hugetlb_report_node_meminfo(int, char *);
unsigned long hugetlb_total_pages(void);
int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, int write_access);
int hugetlb_reserve_pages(struct inode *inode, long from, long to);
void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed);
extern unsigned long max_huge_pages;
extern const unsigned long hugetlb_zero, hugetlb_infinity;
extern int sysctl_hugetlb_shm_group;
/* arch callbacks */
pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr);
pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr);
struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
int write);
struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
pmd_t *pmd, int write);
int pmd_huge(pmd_t pmd);
void hugetlb_change_protection(struct vm_area_struct *vma,
unsigned long address, unsigned long end, pgprot_t newprot);
#ifndef ARCH_HAS_HUGEPAGE_ONLY_RANGE
#define is_hugepage_only_range(mm, addr, len) 0
#endif
#ifndef ARCH_HAS_HUGETLB_FREE_PGD_RANGE
#define hugetlb_free_pgd_range free_pgd_range
#else
void hugetlb_free_pgd_range(struct mmu_gather **tlb, unsigned long addr,
unsigned long end, unsigned long floor,
unsigned long ceiling);
#endif
#ifndef ARCH_HAS_PREPARE_HUGEPAGE_RANGE
/*
* If the arch doesn't supply something else, assume that hugepage
* size aligned regions are ok without further preparation.
*/
static inline int prepare_hugepage_range(unsigned long addr, unsigned long len,
pgoff_t pgoff)
{
if (pgoff & (~HPAGE_MASK >> PAGE_SHIFT))
return -EINVAL;
if (len & ~HPAGE_MASK)
return -EINVAL;
if (addr & ~HPAGE_MASK)
return -EINVAL;
return 0;
}
#else
int prepare_hugepage_range(unsigned long addr, unsigned long len,
pgoff_t pgoff);
#endif
#ifndef ARCH_HAS_SETCLEAR_HUGE_PTE
#define set_huge_pte_at(mm, addr, ptep, pte) set_pte_at(mm, addr, ptep, pte)
#define huge_ptep_get_and_clear(mm, addr, ptep) ptep_get_and_clear(mm, addr, ptep)
#else
void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte);
pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
pte_t *ptep);
#endif
#ifndef ARCH_HAS_HUGETLB_PREFAULT_HOOK
#define hugetlb_prefault_arch_hook(mm) do { } while (0)
#else
void hugetlb_prefault_arch_hook(struct mm_struct *mm);
#endif
#else /* !CONFIG_HUGETLB_PAGE */
static inline int is_vm_hugetlb_page(struct vm_area_struct *vma)
{
return 0;
}
static inline unsigned long hugetlb_total_pages(void)
{
return 0;
}
#define follow_hugetlb_page(m,v,p,vs,a,b,i) ({ BUG(); 0; })
#define follow_huge_addr(mm, addr, write) ERR_PTR(-EINVAL)
#define copy_hugetlb_page_range(src, dst, vma) ({ BUG(); 0; })
#define hugetlb_prefault(mapping, vma) ({ BUG(); 0; })
#define unmap_hugepage_range(vma, start, end) BUG()
#define hugetlb_report_meminfo(buf) 0
#define hugetlb_report_node_meminfo(n, buf) 0
#define follow_huge_pmd(mm, addr, pmd, write) NULL
#define prepare_hugepage_range(addr,len,pgoff) (-EINVAL)
#define pmd_huge(x) 0
#define is_hugepage_only_range(mm, addr, len) 0
#define hugetlb_free_pgd_range(tlb, addr, end, floor, ceiling) ({BUG(); 0; })
#define hugetlb_fault(mm, vma, addr, write) ({ BUG(); 0; })
#define hugetlb_change_protection(vma, address, end, newprot)
#ifndef HPAGE_MASK
#define HPAGE_MASK PAGE_MASK /* Keep the compiler happy */
#define HPAGE_SIZE PAGE_SIZE
#endif
#endif /* !CONFIG_HUGETLB_PAGE */
#ifdef CONFIG_HUGETLBFS
struct hugetlbfs_config {
uid_t uid;
gid_t gid;
umode_t mode;
long nr_blocks;
long nr_inodes;
};
struct hugetlbfs_sb_info {
long max_blocks; /* blocks allowed */
long free_blocks; /* blocks free */
long max_inodes; /* inodes allowed */
long free_inodes; /* inodes free */
spinlock_t stat_lock;
};
struct hugetlbfs_inode_info {
struct shared_policy policy;
struct inode vfs_inode;
};
static inline struct hugetlbfs_inode_info *HUGETLBFS_I(struct inode *inode)
{
return container_of(inode, struct hugetlbfs_inode_info, vfs_inode);
}
static inline struct hugetlbfs_sb_info *HUGETLBFS_SB(struct super_block *sb)
{
return sb->s_fs_info;
}
extern const struct file_operations hugetlbfs_file_operations;
extern struct vm_operations_struct hugetlb_vm_ops;
struct file *hugetlb_zero_setup(size_t);
int hugetlb_get_quota(struct address_space *mapping);
void hugetlb_put_quota(struct address_space *mapping);
static inline int is_file_hugepages(struct file *file)
{
return file->f_op == &hugetlbfs_file_operations;
}
static inline void set_file_hugepages(struct file *file)
{
file->f_op = &hugetlbfs_file_operations;
}
#else /* !CONFIG_HUGETLBFS */
#define is_file_hugepages(file) 0
#define set_file_hugepages(file) BUG()
#define hugetlb_zero_setup(size) ERR_PTR(-ENOSYS)
#endif /* !CONFIG_HUGETLBFS */
#endif /* _LINUX_HUGETLB_H */