mm: kill vma flag VM_CAN_NONLINEAR
Move actual pte filling for non-linear file mappings into the new special
vma operation: ->remap_pages().
Filesystems must implement this method to get non-linear mapping support,
if it uses filemap_fault() then generic_file_remap_pages() can be used.
Now device drivers can implement this method and obtain nonlinear vma support.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com> #arch/tile
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/staging/android/ashmem.c b/drivers/staging/android/ashmem.c
index 94a740d..634b9ae 100644
--- a/drivers/staging/android/ashmem.c
+++ b/drivers/staging/android/ashmem.c
@@ -332,7 +332,6 @@
if (vma->vm_file)
fput(vma->vm_file);
vma->vm_file = asma->file;
- vma->vm_flags |= VM_CAN_NONLINEAR;
out:
mutex_unlock(&ashmem_mutex);
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index dd6f7ee..c2483e9 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -738,6 +738,7 @@
static const struct vm_operations_struct v9fs_file_vm_ops = {
.fault = filemap_fault,
.page_mkwrite = v9fs_vm_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 5caf285..f6b40e8 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1599,6 +1599,7 @@
static const struct vm_operations_struct btrfs_file_vm_ops = {
.fault = filemap_fault,
.page_mkwrite = btrfs_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma)
@@ -1610,7 +1611,6 @@
file_accessed(filp);
vma->vm_ops = &btrfs_file_vm_ops;
- vma->vm_flags |= VM_CAN_NONLINEAR;
return 0;
}
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 22b6e45..6690269 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -1224,6 +1224,7 @@
static struct vm_operations_struct ceph_vmops = {
.fault = filemap_fault,
.page_mkwrite = ceph_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
int ceph_mmap(struct file *file, struct vm_area_struct *vma)
@@ -1234,6 +1235,5 @@
return -ENOEXEC;
file_accessed(file);
vma->vm_ops = &ceph_vmops;
- vma->vm_flags |= VM_CAN_NONLINEAR;
return 0;
}
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 7d7bbdc..edb25b4 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -3003,6 +3003,7 @@
static struct vm_operations_struct cifs_file_vm_ops = {
.fault = filemap_fault,
.page_mkwrite = cifs_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
int cifs_file_strict_mmap(struct file *file, struct vm_area_struct *vma)
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index ca6f07a..bf3966b 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -207,6 +207,7 @@
static const struct vm_operations_struct ext4_file_vm_ops = {
.fault = filemap_fault,
.page_mkwrite = ext4_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
@@ -217,7 +218,6 @@
return -ENOEXEC;
file_accessed(file);
vma->vm_ops = &ext4_file_vm_ops;
- vma->vm_flags |= VM_CAN_NONLINEAR;
return 0;
}
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index aba15f1..78d2837 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1379,6 +1379,7 @@
.close = fuse_vma_close,
.fault = filemap_fault,
.page_mkwrite = fuse_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index 30e2199..0def050 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -492,6 +492,7 @@
static const struct vm_operations_struct gfs2_vm_ops = {
.fault = filemap_fault,
.page_mkwrite = gfs2_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
/**
@@ -526,7 +527,6 @@
return error;
}
vma->vm_ops = &gfs2_vm_ops;
- vma->vm_flags |= VM_CAN_NONLINEAR;
return 0;
}
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 6a7fcab..f692be9 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -578,6 +578,7 @@
static const struct vm_operations_struct nfs_file_vm_ops = {
.fault = filemap_fault,
.page_mkwrite = nfs_vm_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
static int nfs_need_sync_write(struct file *filp, struct inode *inode)
diff --git a/fs/nilfs2/file.c b/fs/nilfs2/file.c
index 5b387a4..16f35f7 100644
--- a/fs/nilfs2/file.c
+++ b/fs/nilfs2/file.c
@@ -135,13 +135,13 @@
static const struct vm_operations_struct nilfs_file_vm_ops = {
.fault = filemap_fault,
.page_mkwrite = nilfs_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
static int nilfs_file_mmap(struct file *file, struct vm_area_struct *vma)
{
file_accessed(file);
vma->vm_ops = &nilfs_file_vm_ops;
- vma->vm_flags |= VM_CAN_NONLINEAR;
return 0;
}
diff --git a/fs/ocfs2/mmap.c b/fs/ocfs2/mmap.c
index d150372..47a87dd 100644
--- a/fs/ocfs2/mmap.c
+++ b/fs/ocfs2/mmap.c
@@ -173,6 +173,7 @@
static const struct vm_operations_struct ocfs2_file_vm_ops = {
.fault = ocfs2_fault,
.page_mkwrite = ocfs2_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
int ocfs2_mmap(struct file *file, struct vm_area_struct *vma)
@@ -188,7 +189,6 @@
ocfs2_inode_unlock(file->f_dentry->d_inode, lock_level);
out:
vma->vm_ops = &ocfs2_file_vm_ops;
- vma->vm_flags |= VM_CAN_NONLINEAR;
return 0;
}
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index ff48c5a..5bc7781 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1536,6 +1536,7 @@
static const struct vm_operations_struct ubifs_file_vm_ops = {
.fault = filemap_fault,
.page_mkwrite = ubifs_vm_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
static int ubifs_file_mmap(struct file *file, struct vm_area_struct *vma)
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 1eaeb8b..aa473fa 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -940,7 +940,6 @@
struct vm_area_struct *vma)
{
vma->vm_ops = &xfs_file_vm_ops;
- vma->vm_flags |= VM_CAN_NONLINEAR;
file_accessed(filp);
return 0;
@@ -1443,4 +1442,5 @@
static const struct vm_operations_struct xfs_file_vm_ops = {
.fault = filemap_fault,
.page_mkwrite = xfs_vm_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
diff --git a/include/linux/fs.h b/include/linux/fs.h
index ca6d8c8..5a8a273 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2552,6 +2552,8 @@
extern int generic_file_mmap(struct file *, struct vm_area_struct *);
extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
+extern int generic_file_remap_pages(struct vm_area_struct *, unsigned long addr,
+ unsigned long size, pgoff_t pgoff);
extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
diff --git a/include/linux/mm.h b/include/linux/mm.h
index fb0685b..44d3fc2 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -105,7 +105,6 @@
#define VM_ARCH_1 0x01000000 /* Architecture-specific flag */
#define VM_NODUMP 0x04000000 /* Do not include in the core dump */
-#define VM_CAN_NONLINEAR 0x08000000 /* Has ->fault & does nonlinear pages */
#define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */
#define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */
#define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */
@@ -171,8 +170,7 @@
* of VM_FAULT_xxx flags that give details about how the fault was handled.
*
* pgoff should be used in favour of virtual_address, if possible. If pgoff
- * is used, one may set VM_CAN_NONLINEAR in the vma->vm_flags to get nonlinear
- * mapping support.
+ * is used, one may implement ->remap_pages to get nonlinear mapping support.
*/
struct vm_fault {
unsigned int flags; /* FAULT_FLAG_xxx flags */
@@ -230,6 +228,9 @@
int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from,
const nodemask_t *to, unsigned long flags);
#endif
+ /* called by sys_remap_file_pages() to populate non-linear mapping */
+ int (*remap_pages)(struct vm_area_struct *vma, unsigned long addr,
+ unsigned long size, pgoff_t pgoff);
};
struct mmu_gather;
diff --git a/mm/filemap.c b/mm/filemap.c
index 3843445..a9827b4 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1737,6 +1737,7 @@
const struct vm_operations_struct generic_file_vm_ops = {
.fault = filemap_fault,
.page_mkwrite = filemap_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
/* This is used for a general mmap of a disk file */
@@ -1749,7 +1750,6 @@
return -ENOEXEC;
file_accessed(file);
vma->vm_ops = &generic_file_vm_ops;
- vma->vm_flags |= VM_CAN_NONLINEAR;
return 0;
}
diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c
index 13e013b..9175022 100644
--- a/mm/filemap_xip.c
+++ b/mm/filemap_xip.c
@@ -305,6 +305,7 @@
static const struct vm_operations_struct xip_file_vm_ops = {
.fault = xip_file_fault,
.page_mkwrite = filemap_page_mkwrite,
+ .remap_pages = generic_file_remap_pages,
};
int xip_file_mmap(struct file * file, struct vm_area_struct * vma)
@@ -313,7 +314,7 @@
file_accessed(file);
vma->vm_ops = &xip_file_vm_ops;
- vma->vm_flags |= VM_CAN_NONLINEAR | VM_MIXEDMAP;
+ vma->vm_flags |= VM_MIXEDMAP;
return 0;
}
EXPORT_SYMBOL_GPL(xip_file_mmap);
diff --git a/mm/fremap.c b/mm/fremap.c
index 048659c..3d731a4 100644
--- a/mm/fremap.c
+++ b/mm/fremap.c
@@ -5,6 +5,7 @@
*
* started by Ingo Molnar, Copyright (C) 2002, 2003
*/
+#include <linux/export.h>
#include <linux/backing-dev.h>
#include <linux/mm.h>
#include <linux/swap.h>
@@ -80,9 +81,10 @@
return err;
}
-static int populate_range(struct mm_struct *mm, struct vm_area_struct *vma,
- unsigned long addr, unsigned long size, pgoff_t pgoff)
+int generic_file_remap_pages(struct vm_area_struct *vma, unsigned long addr,
+ unsigned long size, pgoff_t pgoff)
{
+ struct mm_struct *mm = vma->vm_mm;
int err;
do {
@@ -95,9 +97,9 @@
pgoff++;
} while (size);
- return 0;
-
+ return 0;
}
+EXPORT_SYMBOL(generic_file_remap_pages);
/**
* sys_remap_file_pages - remap arbitrary pages of an existing VM_SHARED vma
@@ -167,7 +169,7 @@
if (vma->vm_private_data && !(vma->vm_flags & VM_NONLINEAR))
goto out;
- if (!(vma->vm_flags & VM_CAN_NONLINEAR))
+ if (!vma->vm_ops->remap_pages)
goto out;
if (start < vma->vm_start || start + size > vma->vm_end)
@@ -228,7 +230,7 @@
}
mmu_notifier_invalidate_range_start(mm, start, start + size);
- err = populate_range(mm, vma, start, size, pgoff);
+ err = vma->vm_ops->remap_pages(vma, start, size, pgoff);
mmu_notifier_invalidate_range_end(mm, start, start + size);
if (!err && !(flags & MAP_NONBLOCK)) {
if (vma->vm_flags & VM_LOCKED) {
diff --git a/mm/mmap.c b/mm/mmap.c
index b0989f4..d0686d3 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -669,8 +669,7 @@
static inline int is_mergeable_vma(struct vm_area_struct *vma,
struct file *file, unsigned long vm_flags)
{
- /* VM_CAN_NONLINEAR may get set later by f_op->mmap() */
- if ((vma->vm_flags ^ vm_flags) & ~VM_CAN_NONLINEAR)
+ if (vma->vm_flags ^ vm_flags)
return 0;
if (vma->vm_file != file)
return 0;
diff --git a/mm/nommu.c b/mm/nommu.c
index dee2ff8..98318dc 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1961,6 +1961,14 @@
}
EXPORT_SYMBOL(filemap_fault);
+int generic_file_remap_pages(struct vm_area_struct *vma, unsigned long addr,
+ unsigned long size, pgoff_t pgoff)
+{
+ BUG();
+ return 0;
+}
+EXPORT_SYMBOL(generic_file_remap_pages);
+
static int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm,
unsigned long addr, void *buf, int len, int write)
{
diff --git a/mm/shmem.c b/mm/shmem.c
index d375211..cc12072f 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1339,7 +1339,6 @@
{
file_accessed(file);
vma->vm_ops = &shmem_vm_ops;
- vma->vm_flags |= VM_CAN_NONLINEAR;
return 0;
}
@@ -2643,6 +2642,7 @@
.set_policy = shmem_set_policy,
.get_policy = shmem_get_policy,
#endif
+ .remap_pages = generic_file_remap_pages,
};
static struct dentry *shmem_mount(struct file_system_type *fs_type,
@@ -2836,7 +2836,6 @@
fput(vma->vm_file);
vma->vm_file = file;
vma->vm_ops = &shmem_vm_ops;
- vma->vm_flags |= VM_CAN_NONLINEAR;
return 0;
}