mm: implement ->map_pages for page cache
filemap_map_pages() is generic implementation of ->map_pages() for
filesystems who uses page cache.
It should be safe to use filemap_map_pages() for ->map_pages() if
filesystem use filemap_fault() for ->fault().
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ning Qu <quning@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index a16b0ff4..d822320 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -832,6 +832,7 @@
static const struct vm_operations_struct v9fs_file_vm_ops = {
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = v9fs_vm_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
@@ -839,6 +840,7 @@
static const struct vm_operations_struct v9fs_mmap_file_vm_ops = {
.close = v9fs_mmap_vm_close,
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.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 e1ffb1e..c660527 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2025,6 +2025,7 @@
static const struct vm_operations_struct btrfs_file_vm_ops = {
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = btrfs_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 834fce7..216d7e9 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -3113,6 +3113,7 @@
static struct vm_operations_struct cifs_file_vm_ops = {
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = cifs_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 6db7f7d..4e508fc 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -200,6 +200,7 @@
static const struct vm_operations_struct ext4_file_vm_ops = {
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = ext4_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 0dfcef5..129a3bd 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -84,6 +84,7 @@
static const struct vm_operations_struct f2fs_file_vm_ops = {
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = f2fs_vm_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 65df7d8..48992ca 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -2117,6 +2117,7 @@
static const struct vm_operations_struct fuse_file_vm_ops = {
.close = fuse_vma_close,
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = fuse_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index 6c79408..80d6725 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -494,6 +494,7 @@
static const struct vm_operations_struct gfs2_vm_ops = {
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = gfs2_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 5bb790a..284ca90 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -617,6 +617,7 @@
static const struct vm_operations_struct nfs_file_vm_ops = {
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = nfs_vm_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
diff --git a/fs/nilfs2/file.c b/fs/nilfs2/file.c
index 08fdb77..f3a82fb 100644
--- a/fs/nilfs2/file.c
+++ b/fs/nilfs2/file.c
@@ -134,6 +134,7 @@
static const struct vm_operations_struct nilfs_file_vm_ops = {
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = nilfs_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 123c79b..4f34dba 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1538,6 +1538,7 @@
static const struct vm_operations_struct ubifs_file_vm_ops = {
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = ubifs_vm_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index f7abff8..003c005 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1483,6 +1483,7 @@
static const struct vm_operations_struct xfs_file_vm_ops = {
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = xfs_vm_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
diff --git a/include/linux/mm.h b/include/linux/mm.h
index f710d32..9132fae 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1847,6 +1847,7 @@
/* generic vm_area_ops exported for stackable file systems */
extern int filemap_fault(struct vm_area_struct *, struct vm_fault *);
+extern void filemap_map_pages(struct vm_area_struct *vma, struct vm_fault *vmf);
extern int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
/* mm/page-writeback.c */
diff --git a/mm/filemap.c b/mm/filemap.c
index 21781f1..3f9b5fb 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -33,6 +33,7 @@
#include <linux/hardirq.h> /* for BUG_ON(!in_atomic()) only */
#include <linux/memcontrol.h>
#include <linux/cleancache.h>
+#include <linux/rmap.h>
#include "internal.h"
#define CREATE_TRACE_POINTS
@@ -2064,6 +2065,78 @@
}
EXPORT_SYMBOL(filemap_fault);
+void filemap_map_pages(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct radix_tree_iter iter;
+ void **slot;
+ struct file *file = vma->vm_file;
+ struct address_space *mapping = file->f_mapping;
+ loff_t size;
+ struct page *page;
+ unsigned long address = (unsigned long) vmf->virtual_address;
+ unsigned long addr;
+ pte_t *pte;
+
+ rcu_read_lock();
+ radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, vmf->pgoff) {
+ if (iter.index > vmf->max_pgoff)
+ break;
+repeat:
+ page = radix_tree_deref_slot(slot);
+ if (unlikely(!page))
+ goto next;
+ if (radix_tree_exception(page)) {
+ if (radix_tree_deref_retry(page))
+ break;
+ else
+ goto next;
+ }
+
+ if (!page_cache_get_speculative(page))
+ goto repeat;
+
+ /* Has the page moved? */
+ if (unlikely(page != *slot)) {
+ page_cache_release(page);
+ goto repeat;
+ }
+
+ if (!PageUptodate(page) ||
+ PageReadahead(page) ||
+ PageHWPoison(page))
+ goto skip;
+ if (!trylock_page(page))
+ goto skip;
+
+ if (page->mapping != mapping || !PageUptodate(page))
+ goto unlock;
+
+ size = i_size_read(mapping->host) + PAGE_CACHE_SIZE - 1;
+ if (page->index >= size >> PAGE_CACHE_SHIFT)
+ goto unlock;
+
+ pte = vmf->pte + page->index - vmf->pgoff;
+ if (!pte_none(*pte))
+ goto unlock;
+
+ if (file->f_ra.mmap_miss > 0)
+ file->f_ra.mmap_miss--;
+ addr = address + (page->index - vmf->pgoff) * PAGE_SIZE;
+ do_set_pte(vma, addr, page, pte, false, false);
+ unlock_page(page);
+ goto next;
+unlock:
+ unlock_page(page);
+skip:
+ page_cache_release(page);
+next:
+ if (iter.index == vmf->max_pgoff)
+ break;
+ }
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(filemap_map_pages);
+
int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct page *page = vmf->page;
@@ -2093,6 +2166,7 @@
const struct vm_operations_struct generic_file_vm_ops = {
.fault = filemap_fault,
+ .map_pages = filemap_map_pages,
.page_mkwrite = filemap_page_mkwrite,
.remap_pages = generic_file_remap_pages,
};
diff --git a/mm/nommu.c b/mm/nommu.c
index a554e5a..e194825 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1985,6 +1985,12 @@
}
EXPORT_SYMBOL(filemap_fault);
+void filemap_map_pages(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ BUG();
+}
+EXPORT_SYMBOL(filemap_map_pages);
+
int generic_file_remap_pages(struct vm_area_struct *vma, unsigned long addr,
unsigned long size, pgoff_t pgoff)
{