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linux/fs/ecryptfs
Tyler Hicks 821f7494a7 eCryptfs: Revert to a writethrough cache model
A change was made about a year ago to get eCryptfs to better utilize its
page cache during writes. The idea was to do the page encryption
operations during page writeback, rather than doing them when initially
writing into the page cache, to reduce the number of page encryption
operations during sequential writes. This meant that the encrypted page
would only be written to the lower filesystem during page writeback,
which was a change from how eCryptfs had previously wrote to the lower
filesystem in ecryptfs_write_end().

The change caused a few eCryptfs-internal bugs that were shook out.
Unfortunately, more grave side effects have been identified that will
force changes outside of eCryptfs. Because the lower filesystem isn't
consulted until page writeback, eCryptfs has no way to pass lower write
errors (ENOSPC, mainly) back to userspace. Additionaly, it was reported
that quotas could be bypassed because of the way eCryptfs may sometimes
open the lower filesystem using a privileged kthread.

It would be nice to resolve the latest issues, but it is best if the
eCryptfs commits be reverted to the old behavior in the meantime.

This reverts:
32001d6f "eCryptfs: Flush file in vma close"
5be79de2 "eCryptfs: Flush dirty pages in setattr"
57db4e8d "ecryptfs: modify write path to encrypt page in writepage"

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Tested-by: Colin King <colin.king@canonical.com>
Cc: Colin King <colin.king@canonical.com>
Cc: Thieu Le <thieule@google.com>
2012-07-13 16:46:06 -07:00
..
crypto.c eCryptfs: Improve statfs reporting 2012-02-16 16:06:21 -06:00
debug.c
dentry.c eCryptfs: Handle NULL nameidata pointers 2011-02-21 14:45:57 -06:00
ecryptfs_kernel.h eCryptfs: Initialize empty lower files when opening them 2012-07-08 12:51:45 -05:00
file.c eCryptfs: Revert to a writethrough cache model 2012-07-13 16:46:06 -07:00
inode.c eCryptfs: Revert to a writethrough cache model 2012-07-13 16:46:06 -07:00
Kconfig eCryptfs: fix compile error 2011-08-09 13:42:46 -05:00
keystore.c eCryptfs: Improve statfs reporting 2012-02-16 16:06:21 -06:00
kthread.c eCryptfs: Properly check for O_RDONLY flag before doing privileged open 2012-07-03 16:34:09 -07:00
main.c eCryptfs: Copy up POSIX ACL and read-only flags from lower mount 2012-07-08 12:51:43 -05:00
Makefile
messaging.c eCryptfs: Make all miscdev functions use daemon ptr in file private_data 2012-07-08 12:51:44 -05:00
miscdev.c eCryptfs: Make all miscdev functions use daemon ptr in file private_data 2012-07-08 12:51:44 -05:00
mmap.c eCryptfs: Revert to a writethrough cache model 2012-07-13 16:46:06 -07:00
read_write.c ecryptfs: remove the second argument of k[un]map_atomic() 2012-02-16 16:06:27 -06:00
super.c vfs: Rename end_writeback() to clear_inode() 2012-05-06 13:43:41 +08:00