diff options
| author | Steven Whitehouse <swhiteho@redhat.com> | 2007-04-20 09:18:30 +0100 |
|---|---|---|
| committer | Steven Whitehouse <swhiteho@redhat.com> | 2007-05-01 09:11:46 +0100 |
| commit | bf126aee6d54fe1e509846abf3b27aba84c6d7ce (patch) | |
| tree | 5d21f057b2d5ee00cab9ac25f5d0e160bf57d533 /fs | |
| parent | 476c006be009d4121e401a9e9f49a3362a7a272f (diff) | |
| download | linux-bf126aee6d54fe1e509846abf3b27aba84c6d7ce.tar.bz2 | |
[GFS2] Patch to fix mmap of stuffed files
If a stuffed file is mmaped and a page fault is generated at some offset
above the initial page, we need to create a zero page to hang the buffer
heads off before we can unstuff the file. This is a fix for bz #236087
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/gfs2/ops_address.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/fs/gfs2/ops_address.c b/fs/gfs2/ops_address.c index 90c287932d58..30c15622174f 100644 --- a/fs/gfs2/ops_address.c +++ b/fs/gfs2/ops_address.c @@ -197,7 +197,19 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page) void *kaddr; int error; - BUG_ON(page->index); + /* + * Due to the order of unstuffing files and ->nopage(), we can be + * asked for a zero page in the case of a stuffed file being extended, + * so we need to supply one here. It doesn't happen often. + */ + if (unlikely(page->index)) { + kaddr = kmap_atomic(page, KM_USER0); + memset(kaddr, 0, PAGE_CACHE_SIZE); + kunmap_atomic(kaddr, KM_USER0); + flush_dcache_page(page); + SetPageUptodate(page); + return 0; + } error = gfs2_meta_inode_buffer(ip, &dibh); if (error) @@ -208,9 +220,8 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page) ip->i_di.di_size); memset(kaddr + ip->i_di.di_size, 0, PAGE_CACHE_SIZE - ip->i_di.di_size); kunmap_atomic(kaddr, KM_USER0); - + flush_dcache_page(page); brelse(dibh); - SetPageUptodate(page); return 0; |