[PATCHv3 38/41] ext4: fix SEEK_DATA/SEEK_HOLE for huge pages
From: Kirill A. Shutemov <hidden>
Date: 2016-09-15 11:55:20
Also in:
linux-ext4, linux-fsdevel, linux-mm, lkml
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
ext4_find_unwritten_pgoff() needs few tweaks to work with huge pages. Mostly trivial page_mapping()/page_to_pgoff() and adjustment to how we find relevant block. Signe-off-by: Kirill A. Shutemov [off-list ref] --- fs/ext4/file.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-)
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 261ac3734c58..2c3d6bb0edfe 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c@@ -473,7 +473,7 @@ static int ext4_find_unwritten_pgoff(struct inode *inode, * range, it will be a hole. */ if (lastoff < endoff && whence == SEEK_HOLE && - page->index > end) { + page_to_pgoff(page) > end) { found = 1; *offset = lastoff; goto out;
@@ -481,7 +481,7 @@ static int ext4_find_unwritten_pgoff(struct inode *inode, lock_page(page); - if (unlikely(page->mapping != inode->i_mapping)) { + if (unlikely(page_mapping(page) != inode->i_mapping)) { unlock_page(page); continue; }
@@ -492,8 +492,12 @@ static int ext4_find_unwritten_pgoff(struct inode *inode, } if (page_has_buffers(page)) { + int diff; lastoff = page_offset(page); bh = head = page_buffers(page); + diff = (page - compound_head(page)) << inode->i_blkbits; + while (diff--) + bh = bh->b_this_page; do { if (buffer_uptodate(bh) || buffer_unwritten(bh)) {
@@ -514,8 +518,12 @@ static int ext4_find_unwritten_pgoff(struct inode *inode, } while (bh != head); } - lastoff = page_offset(page) + PAGE_SIZE; + lastoff = page_offset(page) + hpage_size(page); unlock_page(page); + if (PageTransCompound(page)) { + i++; + break; + } } /*
@@ -528,7 +536,9 @@ static int ext4_find_unwritten_pgoff(struct inode *inode, break; } - index = pvec.pages[i - 1]->index + 1; + index = page_to_pgoff(pvec.pages[i - 1]) + 1; + if (PageTransCompound(pvec.pages[i - 1])) + index = round_up(index, HPAGE_PMD_NR); pagevec_release(&pvec); } while (index <= end);
--
2.9.3