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/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;
}