mm, fs: introduce mapping_gfp_constraint()
There are many places which use mapping_gfp_mask to restrict a more
generic gfp mask which would be used for allocations which are not
directly related to the page cache but they are performed in the same
context.
Let's introduce a helper function which makes the restriction explicit and
easier to track. This patch doesn't introduce any functional changes.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Andrew Morton <akpm@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/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 3c2d4ab..1d47d2e 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -491,7 +491,7 @@
* __GFP_DMA32 to be set in mapping_gfp_mask(inode->i_mapping)
* so shmem can relocate pages during swapin if required.
*/
- BUG_ON((mapping_gfp_mask(mapping) & __GFP_DMA32) &&
+ BUG_ON(mapping_gfp_constraint(mapping, __GFP_DMA32) &&
(page_to_pfn(p) >= 0x00100000UL));
}
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 7e505d4..399aab2 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2214,9 +2214,8 @@
* Fail silently without starting the shrinker
*/
mapping = file_inode(obj->base.filp)->i_mapping;
- gfp = mapping_gfp_mask(mapping);
+ gfp = mapping_gfp_constraint(mapping, ~(__GFP_IO | __GFP_RECLAIM));
gfp |= __GFP_NORETRY | __GFP_NOWARN;
- gfp &= ~(__GFP_IO | __GFP_RECLAIM);
sg = st->sgl;
st->nents = 0;
for (i = 0; i < page_count; i++) {
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 57ee8ca..36dfeff 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -482,13 +482,12 @@
goto next;
}
- page = __page_cache_alloc(mapping_gfp_mask(mapping) &
- ~__GFP_FS);
+ page = __page_cache_alloc(mapping_gfp_constraint(mapping,
+ ~__GFP_FS));
if (!page)
break;
- if (add_to_page_cache_lru(page, mapping, pg_index,
- GFP_NOFS)) {
+ if (add_to_page_cache_lru(page, mapping, pg_index, GFP_NOFS)) {
page_cache_release(page);
goto next;
}
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 938efe3..eb90f0f 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3316,7 +3316,7 @@
static inline gfp_t btrfs_alloc_write_mask(struct address_space *mapping)
{
- return mapping_gfp_mask(mapping) & ~__GFP_FS;
+ return mapping_gfp_constraint(mapping, ~__GFP_FS);
}
/* extent-tree.c */
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index abe3a66..ed05da1 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -85,8 +85,8 @@
}
mapping_set_gfp_mask(inode->i_mapping,
- mapping_gfp_mask(inode->i_mapping) &
- ~(__GFP_FS | __GFP_HIGHMEM));
+ mapping_gfp_constraint(inode->i_mapping,
+ ~(__GFP_FS | __GFP_HIGHMEM)));
return inode;
}
diff --git a/fs/buffer.c b/fs/buffer.c
index 82283ab..51aff02 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -999,7 +999,7 @@
int ret = 0; /* Will call free_more_memory() */
gfp_t gfp_mask;
- gfp_mask = (mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS) | gfp;
+ gfp_mask = mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS) | gfp;
/*
* XXX: __getblk_slow() can not really deal with failure and
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 9d23e78..b7d218a 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -1283,8 +1283,8 @@
int ret1;
struct address_space *mapping = inode->i_mapping;
struct page *page = find_or_create_page(mapping, 0,
- mapping_gfp_mask(mapping) &
- ~__GFP_FS);
+ mapping_gfp_constraint(mapping,
+ ~__GFP_FS));
if (!page) {
ret = VM_FAULT_OOM;
goto out;
@@ -1428,7 +1428,8 @@
if (i_size_read(inode) == 0)
return;
page = find_or_create_page(mapping, 0,
- mapping_gfp_mask(mapping) & ~__GFP_FS);
+ mapping_gfp_constraint(mapping,
+ ~__GFP_FS));
if (!page)
return;
if (PageUptodate(page)) {
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 47c5c97..0068e82 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -3380,7 +3380,7 @@
struct page *page, *tpage;
unsigned int expected_index;
int rc;
- gfp_t gfp = GFP_KERNEL & mapping_gfp_mask(mapping);
+ gfp_t gfp = mapping_gfp_constraint(mapping, GFP_KERNEL);
INIT_LIST_HEAD(tmplist);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 612fbcf..60aaecd 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3344,7 +3344,7 @@
int err = 0;
page = find_or_create_page(mapping, from >> PAGE_CACHE_SHIFT,
- mapping_gfp_mask(mapping) & ~__GFP_FS);
+ mapping_gfp_constraint(mapping, ~__GFP_FS));
if (!page)
return -ENOMEM;
diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
index 560af04..1061611 100644
--- a/fs/ext4/readpage.c
+++ b/fs/ext4/readpage.c
@@ -166,7 +166,7 @@
page = list_entry(pages->prev, struct page, lru);
list_del(&page->lru);
if (add_to_page_cache_lru(page, mapping, page->index,
- GFP_KERNEL & mapping_gfp_mask(mapping)))
+ mapping_gfp_constraint(mapping, GFP_KERNEL)))
goto next_page;
}
diff --git a/fs/logfs/segment.c b/fs/logfs/segment.c
index 7f9b096..6de0fbf 100644
--- a/fs/logfs/segment.c
+++ b/fs/logfs/segment.c
@@ -57,7 +57,7 @@
filler_t *filler = super->s_devops->readpage;
struct page *page;
- BUG_ON(mapping_gfp_mask(mapping) & __GFP_FS);
+ BUG_ON(mapping_gfp_constraint(mapping, __GFP_FS));
if (use_filler)
page = read_cache_page(mapping, index, filler, sb);
else {
diff --git a/fs/mpage.c b/fs/mpage.c
index 09abba7..1480d3a 100644
--- a/fs/mpage.c
+++ b/fs/mpage.c
@@ -361,7 +361,7 @@
sector_t last_block_in_bio = 0;
struct buffer_head map_bh;
unsigned long first_logical_block = 0;
- gfp_t gfp = GFP_KERNEL & mapping_gfp_mask(mapping);
+ gfp_t gfp = mapping_gfp_constraint(mapping, GFP_KERNEL);
map_bh.b_state = 0;
map_bh.b_size = 0;
@@ -397,7 +397,7 @@
sector_t last_block_in_bio = 0;
struct buffer_head map_bh;
unsigned long first_logical_block = 0;
- gfp_t gfp = GFP_KERNEL & mapping_gfp_mask(page->mapping);
+ gfp_t gfp = mapping_gfp_constraint(page->mapping, GFP_KERNEL);
map_bh.b_state = 0;
map_bh.b_size = 0;
diff --git a/fs/namei.c b/fs/namei.c
index 0d3340b..3c18970 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -4604,7 +4604,7 @@
int page_symlink(struct inode *inode, const char *symname, int len)
{
return __page_symlink(inode, symname, len,
- !(mapping_gfp_mask(inode->i_mapping) & __GFP_FS));
+ !mapping_gfp_constraint(inode->i_mapping, __GFP_FS));
}
EXPORT_SYMBOL(page_symlink);
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 4a73d6d..ac2f649 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -356,7 +356,7 @@
goto failed;
mapping_set_gfp_mask(inode->i_mapping,
- mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
+ mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
root = NILFS_I(dir)->i_root;
ii = NILFS_I(inode);
@@ -522,7 +522,7 @@
up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
nilfs_set_inode_flags(inode);
mapping_set_gfp_mask(inode->i_mapping,
- mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
+ mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
return 0;
failed_unmap:
diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index 262561f..9d383e5 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -525,8 +525,8 @@
}
}
err = add_to_page_cache_lru(*cached_page, mapping,
- index,
- GFP_KERNEL & mapping_gfp_mask(mapping));
+ index,
+ mapping_gfp_constraint(mapping, GFP_KERNEL));
if (unlikely(err)) {
if (err == -EEXIST)
continue;
diff --git a/fs/splice.c b/fs/splice.c
index 5fc1e50..801c21c 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -360,7 +360,7 @@
break;
error = add_to_page_cache_lru(page, mapping, index,
- GFP_KERNEL & mapping_gfp_mask(mapping));
+ mapping_gfp_constraint(mapping, GFP_KERNEL));
if (unlikely(error)) {
page_cache_release(page);
if (error == -EEXIST)
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index a6c78e0..26eabf5 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -69,6 +69,13 @@
return (__force gfp_t)mapping->flags & __GFP_BITS_MASK;
}
+/* Restricts the given gfp_mask to what the mapping allows. */
+static inline gfp_t mapping_gfp_constraint(struct address_space *mapping,
+ gfp_t gfp_mask)
+{
+ return mapping_gfp_mask(mapping) & gfp_mask;
+}
+
/*
* This is non-atomic. Only to be used before the mapping is activated.
* Probably needs a barrier...
diff --git a/mm/filemap.c b/mm/filemap.c
index 6ef3674..1bb00762 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1722,7 +1722,7 @@
goto out;
}
error = add_to_page_cache_lru(page, mapping, index,
- GFP_KERNEL & mapping_gfp_mask(mapping));
+ mapping_gfp_constraint(mapping, GFP_KERNEL));
if (error) {
page_cache_release(page);
if (error == -EEXIST) {
@@ -1824,7 +1824,7 @@
return -ENOMEM;
ret = add_to_page_cache_lru(page, mapping, offset,
- GFP_KERNEL & mapping_gfp_mask(mapping));
+ mapping_gfp_constraint(mapping, GFP_KERNEL));
if (ret == 0)
ret = mapping->a_ops->readpage(file, page);
else if (ret == -EEXIST)
diff --git a/mm/readahead.c b/mm/readahead.c
index 998ad59..ba22d7f 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -90,7 +90,7 @@
page = list_to_page(pages);
list_del(&page->lru);
if (add_to_page_cache_lru(page, mapping, page->index,
- GFP_KERNEL & mapping_gfp_mask(mapping))) {
+ mapping_gfp_constraint(mapping, GFP_KERNEL))) {
read_cache_pages_invalidate_page(mapping, page);
continue;
}
@@ -128,7 +128,7 @@
struct page *page = list_to_page(pages);
list_del(&page->lru);
if (!add_to_page_cache_lru(page, mapping, page->index,
- GFP_KERNEL & mapping_gfp_mask(mapping))) {
+ mapping_gfp_constraint(mapping, GFP_KERNEL))) {
mapping->a_ops->readpage(filp, page);
}
page_cache_release(page);