linux/fs
FUJITA Tomonori ecb554a846 block: fix sg SG_DXFER_TO_FROM_DEV regression
I overlooked SG_DXFER_TO_FROM_DEV support when I converted sg to use
the block layer mapping API (2.6.28).

Douglas Gilbert explained SG_DXFER_TO_FROM_DEV:

http://www.spinics.net/lists/linux-scsi/msg37135.html

=
The semantics of SG_DXFER_TO_FROM_DEV were:
   - copy user space buffer to kernel (LLD) buffer
   - do SCSI command which is assumed to be of the DATA_IN
     (data from device) variety. This would overwrite
     some or all of the kernel buffer
   - copy kernel (LLD) buffer back to the user space.

The idea was to detect short reads by filling the original
user space buffer with some marker bytes ("0xec" it would
seem in this report). The "resid" value is a better way
of detecting short reads but that was only added this century
and requires co-operation from the LLD.
=

This patch changes the block layer mapping API to support this
semantics. This simply adds another field to struct rq_map_data and
enables __bio_copy_iov() to copy data from user space even with READ
requests.

It's better to add the flags field and kills null_mapped and the new
from_user fields in struct rq_map_data but that approach makes it
difficult to send this patch to stable trees because st and osst
drivers use struct rq_map_data (they were converted to use the block
layer in 2.6.29 and 2.6.30). Well, I should clean up the block layer
mapping API.

zhou sf reported this regiression and tested this patch:

http://www.spinics.net/lists/linux-scsi/msg37128.html
http://www.spinics.net/lists/linux-scsi/msg37168.html

Reported-by: zhou sf <sxzzsf@gmail.com>
Tested-by: zhou sf <sxzzsf@gmail.com>
Cc: stable@kernel.org
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-07-10 20:31:53 +02:00
..
9p 9P doesn't need BKL in ->umount_begin() 2009-06-17 00:36:36 -04:00
adfs Cleanup of adfs headers 2009-06-17 00:36:36 -04:00
affs affs: add ->sync_fs 2009-06-11 21:36:14 -04:00
afs headers: mnt_namespace.h redux 2009-07-08 09:31:56 -07:00
autofs switch follow_down() 2009-06-11 21:36:01 -04:00
autofs4 switch follow_down() 2009-06-11 21:36:01 -04:00
befs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2009-06-17 08:46:57 -07:00
bfs bfs: add ->sync_fs 2009-06-11 21:36:14 -04:00
btrfs Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable 2009-07-02 16:52:38 -07:00
cachefiles enforce ->sync_fs is only called for rw superblock 2009-06-11 21:36:06 -04:00
cifs cifs: when ATTR_READONLY is set, only clear write bits on non-directories 2009-07-09 23:06:04 +00:00
coda splice: implement default splice_read method 2009-05-11 14:13:10 +02:00
configfs configfs: Rework configfs_depend_item() locking and make lockdep happy 2009-04-30 10:48:26 -07:00
cramfs fs/cramfs: return f_fsid for statfs(2) 2009-04-02 19:05:08 -07:00
debugfs debugfs: use specified mode to possibly mark files read/write only 2009-06-15 21:30:28 -07:00
devpts devpts: remove module-related code 2009-06-24 08:15:24 -04:00
dlm dlm: use more NOFS allocation 2009-05-15 11:24:59 -05:00
ecryptfs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
efs get rid of BKL in fs/efs 2009-06-17 00:36:36 -04:00
exofs [SCSI] Merge branch 'linus' 2009-06-12 10:02:03 -05:00
exportfs
ext2 ext2: return -EIO not -ESTALE on directory traversal through deleted inode 2009-06-30 18:56:00 -07:00
ext3 helpers for acl caching + switch to those 2009-06-24 08:17:07 -04:00
ext4 helpers for acl caching + switch to those 2009-06-24 08:17:07 -04:00
fat Fix congestion_wait() sync/async vs read/write confusion 2009-07-10 20:31:53 +02:00
freevxfs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
fscache FS-Cache: Fixup renamed filenames in comments in internal.h 2009-05-27 10:20:13 -07:00
fuse Fix congestion_wait() sync/async vs read/write confusion 2009-07-10 20:31:53 +02:00
gfs2 block: rename CONFIG_LBD to CONFIG_LBDAF 2009-06-19 08:08:50 +02:00
hfs hfs: add ->sync_fs 2009-06-11 21:36:15 -04:00
hfsplus hfsplus: add ->sync_fs 2009-06-11 21:36:16 -04:00
hostfs hostfs: set maximum filesize in superblock for proper LFS support 2009-06-30 18:56:03 -07:00
hpfs Push BKL down into ->remount_fs() 2009-06-11 21:36:11 -04:00
hppfs hppfs: hppfs_read_file() may return -ERROR 2009-04-02 19:04:53 -07:00
hugetlbfs Merge branch 'master' into next 2009-05-22 18:40:59 +10:00
isofs isofs: cleanup mount option processing 2009-06-18 13:03:45 -07:00
jbd jbd: clean up journal_try_to_free_buffers() 2009-06-18 13:03:45 -07:00
jbd2 jbd2: clean up jbd2_journal_try_to_free_buffers() 2009-06-17 20:08:51 -04:00
jffs2 Remove multiple KERN_ prefixes from printk formats 2009-07-08 10:30:03 -07:00
jfs another race fix in jfs_check_acl() 2009-06-24 17:02:42 -04:00
lockd Merge branch 'for-2.6.31' of git://fieldses.org/git/linux-nfsd 2009-06-22 12:55:50 -07:00
minix Making fs/minix/minix.h double including safe 2009-06-22 11:34:42 -07:00
ncpfs NLS: update handling of Unicode 2009-06-15 21:44:43 -07:00
nfs Fix congestion_wait() sync/async vs read/write confusion 2009-07-10 20:31:53 +02:00
nfs_common
nfsd NFSD: Don't hold unrefcounted creds over call to nfsd_setuser() 2009-07-03 10:21:10 -04:00
nilfs2 switch nilfs2 to inode->i_acl 2009-06-24 08:17:05 -04:00
nls NLS: update handling of Unicode 2009-06-15 21:44:43 -07:00
notify fs/notify/inotify: decrement user inotify count on close 2009-07-02 08:23:00 -04:00
ntfs ntfs: use is_power_of_2() function for clarity. 2009-06-16 19:47:48 -07:00
ocfs2 Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2 2009-06-23 19:36:02 -07:00
omfs switch omfs to simple_fsync() 2009-06-11 21:36:13 -04:00
openpromfs
partitions Merge branch 'for-2.6.31' of git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6 2009-06-12 09:29:42 -07:00
proc proc: vmcore - use kzalloc in get_new_element() 2009-06-18 13:03:41 -07:00
qnx4 fs/qnx4: sanitize includes 2009-06-11 21:36:12 -04:00
quota quota: Fix possible deadlock during parallel quotaon and quotaoff 2009-07-07 18:15:21 +02:00
ramfs ramfs: ignore unknown mount options 2009-06-14 17:58:25 -07:00
reiserfs Fix congestion_wait() sync/async vs read/write confusion 2009-07-10 20:31:53 +02:00
romfs ROMFS: romfs_dev_read() error ignored 2009-05-09 10:49:41 -04:00
smbfs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
squashfs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
sysfs Free the memory allocated by memdup_user() in fs/sysfs/bin.c 2009-07-08 09:34:07 -07:00
sysv get rid of BKL in fs/sysv 2009-06-17 00:36:37 -04:00
ubifs helpers for acl caching + switch to those 2009-06-24 08:17:07 -04:00
udf udf: remove redundant tests on unsigned 2009-06-24 13:48:28 +02:00
ufs ufs: sector_t cannot be negative 2009-06-18 13:03:46 -07:00
xfs Fix congestion_wait() sync/async vs read/write confusion 2009-07-10 20:31:53 +02:00
aio.c eventfd: revised interface and cleanups 2009-06-30 18:55:58 -07:00
anon_inodes.c fs: Provide empty .set_page_dirty() aop for anon inodes 2009-06-18 14:46:10 +02:00
attr.c
bad_inode.c
binfmt_aout.c
binfmt_elf_fdpic.c elf_core_dump: use rcu_read_lock() to access ->real_parent 2009-06-18 13:03:52 -07:00
binfmt_elf.c elf: fix one check-after-use 2009-07-01 11:14:28 -07:00
binfmt_em86.c
binfmt_flat.c flat: fix data sections alignment 2009-05-29 08:40:02 -07:00
binfmt_misc.c
binfmt_script.c
binfmt_som.c Don't crap into descriptor table in binfmt_som 2009-03-31 23:00:28 -04:00
bio-integrity.c block: Create bip slabs with embedded integrity vectors 2009-07-01 10:56:25 +02:00
bio.c block: fix sg SG_DXFER_TO_FROM_DEV regression 2009-07-10 20:31:53 +02:00
block_dev.c vfs: Rename fsync_super() to sync_filesystem() (version 4) 2009-06-11 21:36:04 -04:00
buffer.c Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block 2009-06-11 11:10:35 -07:00
char_dev.c fs: Remove i_cindex from struct inode 2009-06-11 21:36:09 -04:00
compat_binfmt_elf.c
compat_ioctl.c fs: Add new pre-allocation ioctls to vfs for compatibility with legacy xfs ioctls 2009-06-24 08:15:27 -04:00
compat.c cred_guard_mutex: do not return -EINTR to user-space 2009-07-06 13:57:04 -07:00
dcache.c dcache: extrace and use d_unlinked() 2009-06-11 21:36:06 -04:00
dcookies.c
direct-io.c block: Do away with the notion of hardsect_size 2009-05-22 23:22:54 +02:00
drop_caches.c mm: remove __invalidate_mapping_pages variant 2009-06-16 19:47:43 -07:00
eventfd.c eventfd: revised interface and cleanups 2009-06-30 18:55:58 -07:00
eventpoll.c epoll: fix nested calls support 2009-06-18 13:03:41 -07:00
exec.c cred_guard_mutex: do not return -EINTR to user-space 2009-07-06 13:57:04 -07:00
fcntl.c send_sigio_to_task: sanitize the usage of fown->signum 2009-06-16 15:36:17 -07:00
fifo.c
file_table.c fs: move mark_files_ro into file_table.c 2009-06-11 21:36:02 -04:00
file.c
filesystems.c fs: Mark get_filesystem_list() as __init function. 2009-04-20 23:02:52 -04:00
fs_struct.c Get rid of indirect include of fs_struct.h 2009-03-31 23:00:27 -04:00
fs-writeback.c cleanup __writeback_single_inode 2009-06-24 08:15:26 -04:00
generic_acl.c New helper - current_umask() 2009-03-31 23:00:26 -04:00
inode.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2009-06-24 10:03:12 -07:00
internal.h Trim a bit of crap from fs.h 2009-06-11 21:36:07 -04:00
ioctl.c fs: Add new pre-allocation ioctls to vfs for compatibility with legacy xfs ioctls 2009-06-24 08:15:27 -04:00
ioprio.c
Kconfig Merge branch 'for-2.6.31' of git://fieldses.org/git/linux-nfsd 2009-06-22 12:55:50 -07:00
Kconfig.binfmt
libfs.c New helper - simple_fsync() 2009-06-11 21:36:11 -04:00
locks.c lockd: call locks_release_private to cleanup per-filesystem state 2009-04-24 16:36:03 -04:00
Makefile nilfs2: update makefile and Kconfig 2009-04-07 08:31:16 -07:00
mbcache.c
mpage.c ext4: Properly initialize the buffer_head state 2009-05-13 15:13:42 -04:00
namei.c integrity: add ima_counts_put (updated) 2009-06-29 08:59:10 +10:00
namespace.c headers: mnt_namespace.h redux 2009-07-08 09:31:56 -07:00
nfsctl.c
no-block.c
open.c fs: Add new pre-allocation ioctls to vfs for compatibility with legacy xfs ioctls 2009-06-24 08:15:27 -04:00
pipe.c splice: implement default splice_read method 2009-05-11 14:13:10 +02:00
pnode.c
pnode.h
posix_acl.c
read_write.c splice: implement default splice_read method 2009-05-11 14:13:10 +02:00
read_write.h
readdir.c
select.c poll: avoid extra wakeups in select/poll 2009-06-16 19:47:48 -07:00
seq_file.c seq_file: add function to write binary data 2009-06-18 13:03:57 -07:00
signalfd.c
splice.c splice: fix kmaps in default_file_splice_write() 2009-05-19 11:37:46 +02:00
stack.c
stat.c kill vfs_stat_fd / vfs_lstat_fd 2009-04-20 23:02:52 -04:00
super.c ... and the same for vfsmount id/mount group id 2009-06-24 08:15:26 -04:00
sync.c sys_sync(): fix 16% performance regression in ffsb create_4k test 2009-07-06 13:57:03 -07:00
timerfd.c
utimes.c
xattr_acl.c
xattr.c fs: introduce mnt_clone_write 2009-06-11 21:36:02 -04:00