kernel.git/fs/cifs/file.c, branch linux-4.12.y

CIFS: Set ->should_dirty in cifs_user_readv()

2017-06-20T22:57:27Z

The current code causes a static checker warning because ITER_IOVEC is zero so the condition is never true. Fixes: 6685c5e2d1ac ("CIFS: Add asynchronous read support through kernel AIO") Signed-off-by: Dan Carpenter Signed-off-by: Steve French

CIFS: silence lockdep splat in cifs_relock_file()

2017-05-10T01:36:02Z

cifs_relock_file() can perform a down_write() on the inode's lock_sem even though it was already performed in cifs_strict_readv(). Lockdep complains about this. AFAICS, there is no problem here, and lockdep just needs to be told that this nesting is OK. ============================================= [ INFO: possible recursive locking detected ] 4.11.0+ #20 Not tainted --------------------------------------------- cat/701 is trying to acquire lock: (&cifsi->lock_sem){++++.+}, at: cifs_reopen_file+0x7a7/0xc00 but task is already holding lock: (&cifsi->lock_sem){++++.+}, at: cifs_strict_readv+0x177/0x310 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&cifsi->lock_sem); lock(&cifsi->lock_sem); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by cat/701: #0: (&cifsi->lock_sem){++++.+}, at: cifs_strict_readv+0x177/0x310 stack backtrace: CPU: 0 PID: 701 Comm: cat Not tainted 4.11.0+ #20 Call Trace: dump_stack+0x85/0xc2 __lock_acquire+0x17dd/0x2260 ? trace_hardirqs_on_thunk+0x1a/0x1c ? preempt_schedule_irq+0x6b/0x80 lock_acquire+0xcc/0x260 ? lock_acquire+0xcc/0x260 ? cifs_reopen_file+0x7a7/0xc00 down_read+0x2d/0x70 ? cifs_reopen_file+0x7a7/0xc00 cifs_reopen_file+0x7a7/0xc00 ? printk+0x43/0x4b cifs_readpage_worker+0x327/0x8a0 cifs_readpage+0x8c/0x2a0 generic_file_read_iter+0x692/0xd00 cifs_strict_readv+0x29f/0x310 generic_file_splice_read+0x11c/0x1c0 do_splice_to+0xa5/0xc0 splice_direct_to_actor+0xfa/0x350 ? generic_pipe_buf_nosteal+0x10/0x10 do_splice_direct+0xb5/0xe0 do_sendfile+0x278/0x3a0 SyS_sendfile64+0xc4/0xe0 entry_SYSCALL_64_fastpath+0x1f/0xbe Signed-off-by: Rabin Vincent Acked-by: Pavel Shilovsky Signed-off-by: Steve French

CIFS: Add asynchronous write support through kernel AIO

2017-05-02T19:57:34Z

This patch adds support to process write calls passed by io_submit() asynchronously. It based on the previously introduced async context that allows to process i/o responses in a separate thread and return the caller immediately for asynchronous calls. This improves writing performance of single threaded applications with increasing of i/o queue depth size. Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French

CIFS: Add asynchronous read support through kernel AIO

2017-05-02T19:57:34Z

This patch adds support to process read calls passed by io_submit() asynchronously. It based on the previously introduced async context that allows to process i/o responses in a separate thread and return the caller immediately for asynchronous calls. This improves reading performance of single threaded applications with increasing of i/o queue depth size. Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French

CIFS: store results of cifs_reopen_file to avoid infinite wait

2017-04-11T04:36:39Z

This fixes Continuous Availability when errors during file reopen are encountered. cifs_user_readv and cifs_user_writev would wait for ever if results of cifs_reopen_file are not stored and for later inspection. In fact, results are checked and, in case of errors, a chain of function calls leading to reads and writes to be scheduled in a separate thread is skipped. These threads will wake up the corresponding waiters once reads and writes are done. However, given the return value is not stored, when rc is checked for errors a previous one (always zero) is inspected instead. This leads to pending reads/writes added to the list, making cifs_user_readv and cifs_user_writev wait for ever. Signed-off-by: Germano Percossi Reviewed-by: Pavel Shilovsky CC: Stable Signed-off-by: Steve French

mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf

2017-02-25T01:46:54Z

->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to take a vma and vmf parameter when the vma already resides in vmf. Remove the vma parameter to simplify things. [arnd@arndb.de: fix ARM build] Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Dave Jiang Signed-off-by: Arnd Bergmann Reviewed-by: Ross Zwisler Cc: Theodore Ts'o Cc: Darrick J. Wong Cc: Matthew Wilcox Cc: Dave Hansen Cc: Christoph Hellwig Cc: Jan Kara Cc: Dan Williams Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

CIFS: Add copy into pages callback for a read operation

2017-02-01T22:46:36Z

Since we have two different types of reads (pagecache and direct) we need to process such responses differently after decryption of a packet. The change allows to specify a callback that copies a read payload data into preallocated pages. Signed-off-by: Pavel Shilovsky

CIFS: Fix splice read for non-cached files

2017-02-01T22:46:34Z

Currently we call copy_page_to_iter() for uncached reading into a pipe. This is wrong because it treats pages as VFS cache pages and copies references rather than actual data. When we are trying to read from the pipe we end up calling page_cache_pipe_buf_confirm() which returns -ENODATA. This error is translated into 0 which is returned to a user. This issue is reproduced by running xfs-tests suite (generic test #249) against mount points with "cache=none". Fix it by mapping pages manually and calling copy_to_iter() that copies data into the pipe. Cc: Stable Signed-off-by: Pavel Shilovsky

CIFS: Fix a possible double locking of mutex during reconnect

2016-12-05T20:52:01Z

With the current code it is possible to lock a mutex twice when a subsequent reconnects are triggered. On the 1st reconnect we reconnect sessions and tcons and then persistent file handles. If the 2nd reconnect happens during the reconnecting of persistent file handles then the following sequence of calls is observed: cifs_reopen_file -> SMB2_open -> small_smb2_init -> smb2_reconnect -> cifs_reopen_persistent_file_handles -> cifs_reopen_file (again!). So, we are trying to acquire the same cfile->fh_mutex twice which is wrong. Fix this by moving reconnecting of persistent handles to the delayed work (smb2_reconnect_server) and submitting this work every time we reconnect tcon in SMB2 commands handling codepath. This can also lead to corruption of a temporary file list in cifs_reopen_persistent_file_handles() because we can recursively call this function twice. Cc: Stable # v4.9+ Signed-off-by: Pavel Shilovsky

CIFS: Reset read oplock to NONE if we have mandatory locks after reopen

2016-10-14T00:48:59Z

We are already doing the same thing for an ordinary open case: we can't keep read oplock on a file if we have mandatory byte-range locks because pagereading can conflict with these locks on a server. Fix it by setting oplock level to NONE. Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French