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author | Benjamin Marzinski <bmarzins@redhat.com> | 2011-03-17 21:54:46 -0500 |
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committer | Steven Whitehouse <swhiteho@redhat.com> | 2011-04-18 15:22:52 +0100 |
commit | 0ee532062fa7ff0795b3862c2d50efe32e552f9f (patch) | |
tree | 5d8319628ea6d9d5099b7ebd669204ed0070548b /fs/gfs2 | |
parent | deab72d3797e3d4340c7ddf968234b8c3d01d7a5 (diff) | |
download | lwn-0ee532062fa7ff0795b3862c2d50efe32e552f9f.tar.gz lwn-0ee532062fa7ff0795b3862c2d50efe32e552f9f.zip |
GFS2: directly write blocks past i_size
GFS2 was relying on the writepage code to write out the zeroed data for
fallocate. However, with FALLOC_FL_KEEP_SIZE set, this may be past i_size.
If it is, it will be ignored. To work around this, gfs2 now calls
write_dirty_buffer directly on the buffer_heads when FALLOC_FL_KEEP_SIZE
is set, and it's writing past i_size.
This version is just a cleanup of my last version
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Diffstat (limited to 'fs/gfs2')
-rw-r--r-- | fs/gfs2/file.c | 58 |
1 files changed, 48 insertions, 10 deletions
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index b2682e073eee..e48310885c48 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -617,18 +617,51 @@ static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov, return generic_file_aio_write(iocb, iov, nr_segs, pos); } -static void empty_write_end(struct page *page, unsigned from, - unsigned to) +static int empty_write_end(struct page *page, unsigned from, + unsigned to, int mode) { - struct gfs2_inode *ip = GFS2_I(page->mapping->host); + struct inode *inode = page->mapping->host; + struct gfs2_inode *ip = GFS2_I(inode); + struct buffer_head *bh; + unsigned offset, blksize = 1 << inode->i_blkbits; + pgoff_t end_index = i_size_read(inode) >> PAGE_CACHE_SHIFT; zero_user(page, from, to-from); mark_page_accessed(page); - if (!gfs2_is_writeback(ip)) - gfs2_page_add_databufs(ip, page, from, to); + if (page->index < end_index || !(mode & FALLOC_FL_KEEP_SIZE)) { + if (!gfs2_is_writeback(ip)) + gfs2_page_add_databufs(ip, page, from, to); + + block_commit_write(page, from, to); + return 0; + } + + offset = 0; + bh = page_buffers(page); + while (offset < to) { + if (offset >= from) { + set_buffer_uptodate(bh); + mark_buffer_dirty(bh); + clear_buffer_new(bh); + write_dirty_buffer(bh, WRITE); + } + offset += blksize; + bh = bh->b_this_page; + } - block_commit_write(page, from, to); + offset = 0; + bh = page_buffers(page); + while (offset < to) { + if (offset >= from) { + wait_on_buffer(bh); + if (!buffer_uptodate(bh)) + return -EIO; + } + offset += blksize; + bh = bh->b_this_page; + } + return 0; } static int needs_empty_write(sector_t block, struct inode *inode) @@ -643,7 +676,8 @@ static int needs_empty_write(sector_t block, struct inode *inode) return !buffer_mapped(&bh_map); } -static int write_empty_blocks(struct page *page, unsigned from, unsigned to) +static int write_empty_blocks(struct page *page, unsigned from, unsigned to, + int mode) { struct inode *inode = page->mapping->host; unsigned start, end, next, blksize; @@ -668,7 +702,9 @@ static int write_empty_blocks(struct page *page, unsigned from, unsigned to) gfs2_block_map); if (unlikely(ret)) return ret; - empty_write_end(page, start, end); + ret = empty_write_end(page, start, end, mode); + if (unlikely(ret)) + return ret; end = 0; } start = next; @@ -682,7 +718,9 @@ static int write_empty_blocks(struct page *page, unsigned from, unsigned to) ret = __block_write_begin(page, start, end - start, gfs2_block_map); if (unlikely(ret)) return ret; - empty_write_end(page, start, end); + ret = empty_write_end(page, start, end, mode); + if (unlikely(ret)) + return ret; } return 0; @@ -731,7 +769,7 @@ static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len, if (curr == end) to = end_offset; - error = write_empty_blocks(page, from, to); + error = write_empty_blocks(page, from, to, mode); if (!error && offset + to > inode->i_size && !(mode & FALLOC_FL_KEEP_SIZE)) { i_size_write(inode, offset + to); |