linux-toradex.git/drivers/scsi/sg.c, branch v3.16.7

block: add blk_rq_set_block_pc()

2014-06-06T13:57:37+00:00

With the optimizations around not clearing the full request at alloc
time, we are leaving some of the needed init for REQ_TYPE_BLOCK_PC
up to the user allocating the request.

Add a blk_rq_set_block_pc() that sets the command type to
REQ_TYPE_BLOCK_PC, and properly initializes the members associated
with this type of request. Update callers to use this function instead
of manipulating rq->cmd_type directly.

Includes fixes from Christoph Hellwig  for my half-assed
attempt.

Signed-off-by: Jens Axboe

[SCSI] Revert "sg: use rwsem to solve race during exclusive open"

2013-10-25T09:59:54+00:00

This reverts commit 15b06f9a02406e5460001db6d5af5c738cd3d4e7.

This is one of four patches that was causing this bug

[  205.372823] ================================================
[  205.372901] [ BUG: lock held when returning to user space! ]
[  205.372979] 3.12.0-rc6-hw-debug-pagealloc+ #67 Not tainted
[  205.373055] ------------------------------------------------
[  205.373132] megarc.bin/5283 is leaving the kernel with locks still held!
[  205.373212] 1 lock held by megarc.bin/5283:
[  205.373285]  #0:  (&sdp->o_sem){.+.+..}, at: [] sg_open+0x3a0/0x4d0

Cc: Vaughan Cao 
Acked-by: Douglas Gilbert 
Signed-off-by: James Bottomley

[SCSI] Revert "sg: no need sg_open_exclusive_lock"

2013-10-25T09:59:32+00:00

This reverts commit 00b2d9d6d05b56fc1d77071ff8ccbd2c65b48dec.

This is one of four patches that was causing this bug

[  205.372823] ================================================
[  205.372901] [ BUG: lock held when returning to user space! ]
[  205.372979] 3.12.0-rc6-hw-debug-pagealloc+ #67 Not tainted
[  205.373055] ------------------------------------------------
[  205.373132] megarc.bin/5283 is leaving the kernel with locks still held!
[  205.373212] 1 lock held by megarc.bin/5283:
[  205.373285]  #0:  (&sdp->o_sem){.+.+..}, at: [] sg_open+0x3a0/0x4d0

Cc: Vaughan Cao 
Acked-by: Douglas Gilbert 
Signed-off-by: James Bottomley

[SCSI] Revert "sg: checking sdp->detached isn't protected when open"

2013-10-25T09:59:02+00:00

This reverts commit e32c9e6300e3af659cbfe45e90a1e7dcd3572ada.

This is one of four patches that was causing this bug

[  205.372823] ================================================
[  205.372901] [ BUG: lock held when returning to user space! ]
[  205.372979] 3.12.0-rc6-hw-debug-pagealloc+ #67 Not tainted
[  205.373055] ------------------------------------------------
[  205.373132] megarc.bin/5283 is leaving the kernel with locks still held!
[  205.373212] 1 lock held by megarc.bin/5283:
[  205.373285]  #0:  (&sdp->o_sem){.+.+..}, at: [] sg_open+0x3a0/0x4d0

Cc: Vaughan Cao 
Acked-by: Douglas Gilbert 
Signed-off-by: James Bottomley

[SCSI] Revert "sg: push file descriptor list locking down to per-device locking"

2013-10-25T09:58:07+00:00

This reverts commit 1f962ebcdfa15cede59e9edb299d1330949eec92.

This is one of four patches that was causing this bug

[  205.372823] ================================================
[  205.372901] [ BUG: lock held when returning to user space! ]
[  205.372979] 3.12.0-rc6-hw-debug-pagealloc+ #67 Not tainted
[  205.373055] ------------------------------------------------
[  205.373132] megarc.bin/5283 is leaving the kernel with locks still held!
[  205.373212] 1 lock held by megarc.bin/5283:
[  205.373285]  #0:  (&sdp->o_sem){.+.+..}, at: [] sg_open+0x3a0/0x4d0

Cc: Vaughan Cao 
Acked-by: Douglas Gilbert 
Signed-off-by: James Bottomley

[SCSI] sg: push file descriptor list locking down to per-device locking

2013-09-03T14:28:10+00:00

Push file descriptor list locking down to per-device locking. Let sg_index_lock
only protect device lookup.
sdp->detached is also set and checked with this lock held.

Signed-off-by: Vaughan Cao 
Acked-by: Douglas Gilbert 
Signed-off-by: James Bottomley

[SCSI] sg: checking sdp->detached isn't protected when open

2013-09-03T14:28:09+00:00

@detached is set under the protection of sg_index_lock. Without getting the
lock, new sfp will be added during sg removal and there is no chance for it
to be picked out. So check with sg_index_lock held in sg_add_sfp().

Signed-off-by: Vaughan Cao 
Acked-by: Douglas Gilbert 
Signed-off-by: James Bottomley

[SCSI] sg: no need sg_open_exclusive_lock

2013-09-03T14:28:09+00:00

Open exclusive check is protected by o_sem, no need sg_open_exclusive_lock.
@exclude is used to record which type of rwsem we are holding.

Signed-off-by: Vaughan Cao 
Acked-by: Douglas Gilbert 
Signed-off-by: James Bottomley

[SCSI] sg: use rwsem to solve race during exclusive open

2013-09-03T14:28:09+00:00

A race condition may happen if two threads are both trying to open the same sg
with O_EXCL simultaneously. It's possible that they both find fsds list is
empty and get_exclude(sdp) returns 0, then they both call set_exclude() and
break out from wait_event_interruptible and resume open.

Now use rwsem to protect this process. Exclusive open gets write lock and
others get read lock. The lock will be held until file descriptor is closed.
This also leads 'exclude' only a status rather than a check mark.

Signed-off-by: Vaughan Cao 
Acked-by: Douglas Gilbert 
Signed-off-by: James Bottomley

aio: don't include aio.h in sched.h

2013-05-08T03:16:25+00:00

Faster kernel compiles by way of fewer unnecessary includes.

[akpm@linux-foundation.org: fix fallout]
[akpm@linux-foundation.org: fix build]
Signed-off-by: Kent Overstreet 
Cc: Zach Brown 
Cc: Felipe Balbi 
Cc: Greg Kroah-Hartman 
Cc: Mark Fasheh 
Cc: Joel Becker 
Cc: Rusty Russell 
Cc: Jens Axboe 
Cc: Asai Thambi S P 
Cc: Selvan Mani 
Cc: Sam Bradshaw 
Cc: Jeff Moyer 
Cc: Al Viro 
Cc: Benjamin LaHaise 
Reviewed-by: "Theodore Ts'o" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds