diff options
| author | Matthew Wilcox <matthew.r.wilcox@intel.com> | 2014-06-04 16:07:46 -0700 |
|---|---|---|
| committer | Mister Oyster <oysterized@gmail.com> | 2017-05-24 02:20:23 +0200 |
| commit | d84724dc04d62517b355ef8c74a57d3f01232959 (patch) | |
| tree | 97aacbcc9db3892424c6f80cc3fbef1a5892d309 /fs/mpage.c | |
| parent | c1d9c7c120ecd23dc456cdc0fd81373bf7163feb (diff) | |
fs/block_dev.c: add bdev_read_page() and bdev_write_page()
A block device driver may choose to provide a rw_page operation. These
will be called when the filesystem is attempting to do page sized I/O to
page cache pages (ie not for direct I/O). This does preclude I/Os that
are larger than page size, so this may only be a performance gain for
some devices.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Tested-by: Dheeraj Reddy <dheeraj.reddy@intel.com>
Cc: Dave Chinner <david@fromorbit.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>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Diffstat (limited to 'fs/mpage.c')
| -rw-r--r-- | fs/mpage.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/fs/mpage.c b/fs/mpage.c index 0face1c4d..4e15e652e 100644 --- a/fs/mpage.c +++ b/fs/mpage.c @@ -286,6 +286,11 @@ do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages, alloc_new: if (bio == NULL) { + if (first_hole == blocks_per_page) { + if (!bdev_read_page(bdev, blocks[0] << (blkbits - 9), + page)) + goto out; + } bio = mpage_alloc(bdev, blocks[0] << (blkbits - 9), min_t(int, nr_pages, bio_get_nr_vecs(bdev)), GFP_KERNEL); @@ -575,6 +580,13 @@ page_is_mapped: alloc_new: if (bio == NULL) { + if (first_unmapped == blocks_per_page) { + if (!bdev_write_page(bdev, blocks[0] << (blkbits - 9), + page, wbc)) { + clean_buffers(page, first_unmapped); + goto out; + } + } bio = mpage_alloc(bdev, blocks[0] << (blkbits - 9), bio_get_nr_vecs(bdev), GFP_NOFS|__GFP_HIGH); if (bio == NULL) |