f0e6c98593
It can happen that buffers are removed from the page before it gets marked dirty and then is passed to writepage(). In writepage() we just initialize the buffers and check whether they are mapped and non delay. If they are mapped and non delay we write the page. Otherwise we mark them dirty. With this change we don't do block allocation at all in ext4_*_write_page. writepage() can get called under many condition and with a locking order of journal_start -> lock_page, we should not try to allocate blocks in writepage() which get called after taking page lock. writepage() can get called via shrink_page_list even with a journal handle which was created for doing inode update. For example when doing ext4_da_write_begin we create a journal handle with credit 1 expecting a i_disksize update for the inode. But ext4_da_write_begin can cause shrink_page_list via _grab_page_cache. So having a valid handle via ext4_journal_current_handle is not a guarantee that we can use the handle for block allocation in writepage, since we shouldn't be using credits that had been reserved for other updates. That it could result in we running out of credits when we update inodes. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Mingming Cao <cmm@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> |
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.. | ||
acl.c | ||
acl.h | ||
balloc.c | ||
bitmap.c | ||
dir.c | ||
ext4_extents.h | ||
ext4_i.h | ||
ext4_jbd2.c | ||
ext4_jbd2.h | ||
ext4_sb.h | ||
ext4.h | ||
extents.c | ||
file.c | ||
fsync.c | ||
group.h | ||
hash.c | ||
ialloc.c | ||
inode.c | ||
ioctl.c | ||
Makefile | ||
mballoc.c | ||
mballoc.h | ||
migrate.c | ||
namei.c | ||
namei.h | ||
resize.c | ||
super.c | ||
symlink.c | ||
xattr_security.c | ||
xattr_trusted.c | ||
xattr_user.c | ||
xattr.c | ||
xattr.h |