diff options
| author | Bob Liu <lliubbo@gmail.com> | 2012-07-11 14:02:35 -0700 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2012-07-25 04:11:16 +0100 |
| commit | 3501ec357a73226d2b3c1bd204d97926f61b3eae (patch) | |
| tree | 36a7e54312810a8d67bd1d1ac567a75d74a97c2b /fs | |
| parent | d1d5b31c0f73da39cc084af6240601543763f99d (diff) | |
fs: ramfs: file-nommu: add SetPageUptodate()
commit fea9f718b3d68147f162ed2d870183ce5e0ad8d8 upstream.
There is a bug in the below scenario for !CONFIG_MMU:
1. create a new file
2. mmap the file and write to it
3. read the file can't get the correct value
Because
sys_read() -> generic_file_aio_read() -> simple_readpage() -> clear_page()
which causes the page to be zeroed.
Add SetPageUptodate() to ramfs_nommu_expand_for_mapping() so that
generic_file_aio_read() do not call simple_readpage().
Signed-off-by: Bob Liu <lliubbo@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ramfs/file-nommu.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c index fbb0b478a346..d5378d028589 100644 --- a/fs/ramfs/file-nommu.c +++ b/fs/ramfs/file-nommu.c @@ -110,6 +110,7 @@ int ramfs_nommu_expand_for_mapping(struct inode *inode, size_t newsize) /* prevent the page from being discarded on memory pressure */ SetPageDirty(page); + SetPageUptodate(page); unlock_page(page); put_page(page); |