If blk_queue_get() in st_probe fails, disk->queue must not be set to
SDp->request_queue, as that would result in put_disk() dropping a not
taken reference.

Thus, disk->queue should be set only after a successful blk_queue_get().

Fixes: 2b5bebcc ("st: Take additional queue ref in st_probe")
Signed-off-by: NBodo Stroesser <bstroesser@ts.fujitsu.com>
Acked-by: NShirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NEwan D. Milne <emilne@redhat.com>
Acked-by: NKai Mäkisara <kai.makisara@kolumbus.fi>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Instead of explicitly calling scsi_req_init() after blk_get_request(),
call that function from inside blk_get_request(). Add an
.initialize_rq_fn() callback function to the block drivers that need
it. Merge the IDE .init_rq_fn() function into .initialize_rq_fn()
because it is too small to keep it as a separate function. Keep the
scsi_req_init() call in ide_prep_sense() because it follows a
blk_rq_init() call.

References: commit 82ed4db4 ("block: split scsi_request out of struct request")
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Currently we use nornal Linux errno values in the block layer, and while
we accept any error a few have overloaded magic meanings.  This patch
instead introduces a new  blk_status_t value that holds block layer specific
status codes and explicitly explains their meaning.  Helpers to convert from
and to the previous special meanings are provided for now, but I suspect
we want to get rid of them in the long run - those drivers that have a
errno input (e.g. networking) usually get errnos that don't know about
the special block layer overloads, and similarly returning them to userspace
will usually return somethings that strictly speaking isn't correct
for file system operations, but that's left as an exercise for later.

For now the set of errors is a very limited set that closely corresponds
to the previous overloaded errno values, but there is some low hanging
fruite to improve it.

blk_status_t (ab)uses the sparse __bitwise annotations to allow for sparse
typechecking, so that we can easily catch places passing the wrong values.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

This passes on the scsi_cmnd result field to users of passthrough
requests.  Currently we abuse req->errors for this purpose, but that
field will go away in its current form.

Note that the old IDE code abuses the errors field in very creative
ways and stores all kinds of different values in it.  I didn't dare
to touch this magic, so the abuses are brought forward 1:1.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Instead of bloating the generic struct request with it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>

Fix up affected files that include this signal functionality via sched.h.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Instead of keeping two levels of indirection for requests types, fold it
all into the operations.  The little caveat here is that previously
cmd_type only applied to struct request, while the request and bio op
fields were set to plain REQ_OP_READ/WRITE even for passthrough
operations.

Instead this patch adds new REQ_OP_* for SCSI passthrough and driver
private requests, althought it has to add two for each so that we
can communicate the data in/out nature of the request.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

And require all drivers that want to support BLOCK_PC to allocate it
as the first thing of their private data.  To support this the legacy
IDE and BSG code is switched to set cmd_size on their queues to let
the block layer allocate the additional space.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.
Requested-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A lot of the REQ_* flags are only used on struct requests, and only of
use to the block layer and a few drivers that dig into struct request
internals.

This patch adds a new req_flags_t rq_flags field to struct request for
them, and thus dramatically shrinks the number of common requests.  It
also removes the unfortunate situation where we have to fit the fields
from the same enum into 32 bits for struct bio and 64 bits for
struct request.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NShaun Tancheff <shaun.tancheff@seagate.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

This removes the 'write' and 'force' use from get_user_pages_unlocked()
and replaces them with 'gup_flags' to make the use of FOLL_FORCE
explicit in callers as use of this flag can result in surprising
behaviour (and hence bugs) within the mm subsystem.
Signed-off-by: NLorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Acked-by: NMichal Hocko <mhocko@suse.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some drives set the ILI flag together with MEDIUM ERROR sense code.
Clear the ILI flag in this case so that the medium error will be
handled.  The problem was reported by Maurizio Lombardi.
Signed-off-by: NKai Mäkisara <kai.makisara@kolumbus.fi>
Reviewed-by: NLaurence Oberman <loberman@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Change the MTMKPART operation of the MTIOCTOP ioctl so that it works
also with current drives (LTO-5/6, etc.). Send a separate FORMAT MEDIUM
command if the partition mode page indicates that this is required. Use
LOAD to position the tape at the beginning of tape.

The operation is extended so that if the argument is negative, its
absolute value specifies the size of partition 0, which is the
physically first partition of the tape.
Signed-off-by: NKai Mäkisara <kai.makisara@kolumbus.fi>
Tested-by: NShane M Seymour <shane.seymour@hpe.com>
Tested-by: NLaurence Oberman <loberman@redhat.com>
Tested-by: NDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

We will soon modify the vanilla get_user_pages() so it can no
longer be used on mm/tasks other than 'current/current->mm',
which is by far the most common way it is called.  For now,
we allow the old-style calls, but warn when they are used.
(implemented in previous patch)

This patch switches all callers of:

	get_user_pages()
	get_user_pages_unlocked()
	get_user_pages_locked()

to stop passing tsk/mm so they will no longer see the warnings.
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: jack@suse.cz
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20160212210156.113E9407@viggo.jf.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

If cdev_add() returns an error, the code calls
cdev_del() passing the STm->cdevs[rew] pointer as parameter;
the problem is that the pointer has not been initialized yet.

This patch fixes the problem by moving the STm->cdevs[rew] pointer
initialization before the call to cdev_add().
It also sets STm->devs[rew] and STm->cdevs[rew] to NULL in
case of failure.
Signed-off-by: NMaurizio Lombardi <mlombard@redhat.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Change st driver to allow enabling or disabling debug output
via sysfs file /sys/bus/scsi/drivers/st/debug_flag.

Previously the only way to enable debug output was:

1. loading the driver with the module parameter debug_flag=1
2. an ioctl call (this method was also the only way to dynamically
disable debug output).

To use the ioctl you need a second tape drive (if you are
actively testing the first tape drive) since a second process
cannot open the first tape drive if it is in use.

The this change is only functional if the value of the macro
DEBUG in st.c is a non-zero value (which it is by default).
Signed-off-by: NShane Seymour <shane.seymour@hpe.com>
Reviewed-by: NLaurence Oberman <oberman.l@gmail.com>
Acked-by: NKai Mäkisara <kai.makisara@kolumbus.fi>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Destroy st_index_idr on module exit, reclaiming the allocated memory.

This was detected by the following semantic patch (written by Luis Rodriguez
<mcgrof@suse.com>)
<SmPL>
@ defines_module_init @
declarer name module_init, module_exit;
declarer name DEFINE_IDR;
identifier init;
@@

module_init(init);

@ defines_module_exit @
identifier exit;
@@

module_exit(exit);

@ declares_idr depends on defines_module_init && defines_module_exit @
identifier idr;
@@

DEFINE_IDR(idr);

@ on_exit_calls_destroy depends on declares_idr && defines_module_exit @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
 idr_destroy(&idr);
 ...
}

@ missing_module_idr_destroy depends on declares_idr && defines_module_exit && !on_exit_calls_destroy @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
 +idr_destroy(&idr);
}
</SmPL>
Signed-off-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Acked-by: NKai Mäkisara <kai.makisara@kolumbus.fi>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Convert DRIVER_ATTR macros to DRIVER_ATTR_RO requested by
Greg KH. Also switched to using scnprintf instead of snprintf
per Documentation/filesystems/sysfs.txt.
Suggested-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NShane Seymour <shane.seymour@hp.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NKai Mäkisara <kai.makisara@kolumbus.fi>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

This patch changes the st driver to use attribute groups so
driver sysfs files are created automatically. See the
following for reference:

http://kroah.com/log/blog/2013/06/26/how-to-create-a-sysfs-file-correctly/Signed-off-by: NShane Seymour <shane.seymour@hp.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NKai Mäkisara <kai.makisara@kolumbus.fi>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Two SLES11 SP3 servers encountered similar crashes simultaneously
following some kind of SAN/tape target issue:

...
qla2xxx [0000:81:00.0]-801c:3: Abort command issued nexus=3:0:2 --  1 2002.
qla2xxx [0000:81:00.0]-801c:3: Abort command issued nexus=3:0:2 --  1 2002.
qla2xxx [0000:81:00.0]-8009:3: DEVICE RESET ISSUED nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800c:3: do_reset failed for cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800f:3: DEVICE RESET FAILED: Task management failed nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-8009:3: TARGET RESET ISSUED nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800c:3: do_reset failed for cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800f:3: TARGET RESET FAILED: Task management failed nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-8012:3: BUS RESET ISSUED nexus=3:0:2.
qla2xxx [0000:81:00.0]-802b:3: BUS RESET SUCCEEDED nexus=3:0:2.
qla2xxx [0000:81:00.0]-505f:3: Link is operational (8 Gbps).
qla2xxx [0000:81:00.0]-8018:3: ADAPTER RESET ISSUED nexus=3:0:2.
qla2xxx [0000:81:00.0]-00af:3: Performing ISP error recovery - ha=ffff88bf04d18000.
 rport-3:0-0: blocked FC remote port time out: removing target and saving binding
qla2xxx [0000:81:00.0]-505f:3: Link is operational (8 Gbps).
qla2xxx [0000:81:00.0]-8017:3: ADAPTER RESET SUCCEEDED nexus=3:0:2.
 rport-2:0-0: blocked FC remote port time out: removing target and saving binding
sg_rq_end_io: device detached
BUG: unable to handle kernel NULL pointer dereference at 00000000000002a8
IP: [<ffffffff8133b268>] __pm_runtime_idle+0x28/0x90
PGD 7e6586f067 PUD 7e5af06067 PMD 0 [1739975.390354] Oops: 0002 [#1] SMP
CPU 0
...
Supported: No, Proprietary modules are loaded [1739975.390463]
Pid: 27965, comm: ABCD Tainted: PF           X 3.0.101-0.29-default #1 HP ProLiant DL580 Gen8
RIP: 0010:[<ffffffff8133b268>]  [<ffffffff8133b268>] __pm_runtime_idle+0x28/0x90
RSP: 0018:ffff8839dc1e7c68  EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff883f0592fc00 RCX: 0000000000000090
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000138
RBP: 0000000000000138 R08: 0000000000000010 R09: ffffffff81bd39d0
R10: 00000000000009c0 R11: ffffffff81025790 R12: 0000000000000001
R13: ffff883022212b80 R14: 0000000000000004 R15: ffff883022212b80
FS:  00007f8e54560720(0000) GS:ffff88407f800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00000000000002a8 CR3: 0000007e6ced6000 CR4: 00000000001407f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process ABCD (pid: 27965, threadinfo ffff8839dc1e6000, task ffff883592e0c640)
Stack:
 ffff883f0592fc00 00000000fffffffa 0000000000000001 ffff883022212b80
 ffff883eff772400 ffffffffa03fa309 0000000000000000 0000000000000000
 ffffffffa04003a0 ffff883f063196c0 ffff887f0379a930 ffffffff8115ea1e
Call Trace:
 [<ffffffffa03fa309>] st_open+0x129/0x240 [st]
 [<ffffffff8115ea1e>] chrdev_open+0x13e/0x200
 [<ffffffff811588a8>] __dentry_open+0x198/0x310
 [<ffffffff81167d74>] do_last+0x1f4/0x800
 [<ffffffff81168fe9>] path_openat+0xd9/0x420
 [<ffffffff8116946c>] do_filp_open+0x4c/0xc0
 [<ffffffff8115a00f>] do_sys_open+0x17f/0x250
 [<ffffffff81468d92>] system_call_fastpath+0x16/0x1b
 [<00007f8e4f617fd0>] 0x7f8e4f617fcf
Code: eb d3 90 48 83 ec 28 40 f6 c6 04 48 89 6c 24 08 4c 89 74 24 20 48 89 fd 48 89 1c 24 4c 89 64 24 10 41 89 f6 4c 89 6c 24 18 74 11 <f0> ff 8f 70 01 00 00 0f 94 c0 45 31 ed 84 c0 74 2b 4c 8d a5 a0
RIP  [<ffffffff8133b268>] __pm_runtime_idle+0x28/0x90
 RSP <ffff8839dc1e7c68>
CR2: 00000000000002a8

Analysis reveals the cause of the crash to be due to STp->device
being NULL. The pointer was NULLed via scsi_tape_put(STp) when it
calls scsi_tape_release(). In st_open() we jump to err_out after
scsi_block_when_processing_errors() completes and returns the
device as offline (sdev_state was SDEV_DEL):

1180 /* Open the device. Needs to take the BKL only because of incrementing the SCSI host
1181    module count. */
1182 static int st_open(struct inode *inode, struct file *filp)
1183 {
1184         int i, retval = (-EIO);
1185         int resumed = 0;
1186         struct scsi_tape *STp;
1187         struct st_partstat *STps;
1188         int dev = TAPE_NR(inode);
1189         char *name;
...
1217         if (scsi_autopm_get_device(STp->device) < 0) {
1218                 retval = -EIO;
1219                 goto err_out;
1220         }
1221         resumed = 1;
1222         if (!scsi_block_when_processing_errors(STp->device)) {
1223                 retval = (-ENXIO);
1224                 goto err_out;
1225         }
...
1264  err_out:
1265         normalize_buffer(STp->buffer);
1266         spin_lock(&st_use_lock);
1267         STp->in_use = 0;
1268         spin_unlock(&st_use_lock);
1269         scsi_tape_put(STp); <-- STp->device = 0 after this
1270         if (resumed)
1271                 scsi_autopm_put_device(STp->device);
1272         return retval;

The ref count for the struct scsi_tape had already been reduced
to 1 when the .remove method of the st module had been called.
The kref_put() in scsi_tape_put() caused scsi_tape_release()
to be called:

0266 static void scsi_tape_put(struct scsi_tape *STp)
0267 {
0268         struct scsi_device *sdev = STp->device;
0269
0270         mutex_lock(&st_ref_mutex);
0271         kref_put(&STp->kref, scsi_tape_release); <-- calls this
0272         scsi_device_put(sdev);
0273         mutex_unlock(&st_ref_mutex);
0274 }

In scsi_tape_release() the struct scsi_device in the struct
scsi_tape gets set to NULL:

4273 static void scsi_tape_release(struct kref *kref)
4274 {
4275         struct scsi_tape *tpnt = to_scsi_tape(kref);
4276         struct gendisk *disk = tpnt->disk;
4277
4278         tpnt->device = NULL; <<<---- where the dev is nulled
4279
4280         if (tpnt->buffer) {
4281                 normalize_buffer(tpnt->buffer);
4282                 kfree(tpnt->buffer->reserved_pages);
4283                 kfree(tpnt->buffer);
4284         }
4285
4286         disk->private_data = NULL;
4287         put_disk(disk);
4288         kfree(tpnt);
4289         return;
4290 }

Although the problem was reported on SLES11.3 the problem appears
in linux-next as well.

The crash is fixed by reordering the code so we no longer access
the struct scsi_tape after the kref_put() is done on it in st_open().
Signed-off-by: NShane Seymour <shane.seymour@hp.com>
Signed-off-by: NDarren Lavender <darren.lavender@hp.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.com>
Acked-by: NKai Mäkisara <kai.makisara@kolumbus.fi>
Cc: stable@vger.kernel.org
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

This patch implements tape statistics in the st module via
sysfs. Current no statistics are available for tape I/O and there
is no easy way to reuse the block layer statistics for tape
as tape is a character device and does not have perform I/O in
sector sized chunks (the size of the data written to tape
can change). For tapes we also need extra stats related to
things like tape movement (via other I/O).

There have been multiple end users requesting statistics
including AT&T (and some HP customers who have not given
permission to be named). It is impossible for them
to investigate any issues related to tape performance
in a non-invasive way.

[jejb: eliminate PRId64]
Signed-off-by: NShane Seymour <shane.seymour@hp.com>
Tested-by: NShane Seymour <shane.seymour@hp.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

This allows those get_user_pages calls to pass FAULT_FLAG_ALLOW_RETRY to
the page fault in order to release the mmap_sem during the I/O.
Signed-off-by: NAndrea Arcangeli <aarcange@redhat.com>
Reviewed-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Peter Feiner <pfeiner@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The driver core driver structure has grown an owner field and now
requires it to be set for all modular drivers.  Set it up for
all scsi_driver instances and get rid of the now superflous
scsi_driver owner field.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reported-by: NShane M Seymour <shane.seymour@hp.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com
Reviewed-by: NHannes Reinecke <hare@suse.de>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>

The calling conventions for this function are bad as it could return
-ENODEV both for a device not currently online and a not recognized ioctl.

Add a new scsi_ioctl_block_when_processing_errors function that wraps
scsi_block_when_processing_errors with the a special case for the
SG_SCSI_RESET ioctl command, and handle the SG_SCSI_RESET case itself
in scsi_ioctl.  All callers of scsi_ioctl now must call the above helper
to check for the EH state, so that the ioctl handler itself doesn't
have to.
Reported-by: NRobert Elliott <Elliott@hp.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>

We should be using the standard dev_printk() variants for
sense code printing.

[hch: remove __scsi_print_sense call in xen-scsiback, Acked by Juergen]
[hch: folded bracing fix from Dan Carpenter]
Signed-off-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NRobert Elliott <elliott@hp.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Like scmd_printk(), but the device name is passed in as
a string. Can be used by eg ULDs which do not have access
to the scsi_cmnd structure.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NRobert Elliott <elliott@hp.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch adds a debug_flag parameter that can be set on module load, and allows the DEBUG facility without a module recompile.
Note that now DEBUG 1 is the default with this patch.

Usage: modprobe st debug_flag=1
Signed-off-by: NLaurence Oberman <loberman@redhat.com>
Acked-by: NKai M??kisara <kai.makisara@kolumbus.fi>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

SCSI Well-known logical units generally don't have any scsi driver
associated with it which means no one will call scsi_autopm_put_device()
on these wlun scsi devices and this would result in keeping the
corresponding scsi device always active (hence LLD can't be suspended as
well). Same exact problem can be seen for other scsi device representing
normal logical unit whose driver is yet to be loaded. This patch fixes
the above problem with this approach:

- make the scsi_autopm_put_device call at the end of scsi_sysfs_add_sdev
  to make it balance out the get earlier in the function.
- let drivers do paired get/put calls in their probe methods.
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NDolev Raviv <draviv@codeaurora.org>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The blk_get_request function may fail in low-memory conditions or during
device removal (even if __GFP_WAIT is set). To distinguish between these
errors, modify the blk_get_request call stack to return the appropriate
ERR_PTR. Verify that all callers check the return status and consider
IS_ERR instead of a simple NULL pointer check.

For consistency, make a similar change to the blk_mq_alloc_request leg
of blk_get_request.  It may fail if the queue is dead, or the caller was
unwilling to wait.
Signed-off-by: NJoe Lawrence <joe.lawrence@stratus.com>
Acked-by: Jiri Kosina <jkosina@suse.cz> [for pktdvd]
Acked-by: Boaz Harrosh <bharrosh@panasas.com> [for osd]
Reviewed-by: NJeff Moyer <jmoyer@redhat.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Update the st driver to use dev_printk() variants instead of
plain printk(); this will prefix logging messages with the
appropriate device.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

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 <hch@lst.de> for my half-assed
attempt.
Signed-off-by: NJens Axboe <axboe@fb.com>

When copying the st_modedef structures the devs pointers must be preserved
in the same way as with the cdevs pointers.

This fixes bug 70271: https://bugzilla.kernel.org/show_bug.cgi?id=70271

[  135.037052] BUG: unable to handle kernel NULL pointer dereference at 0000000000000098
[  135.045048] IP: [<ffffffff812af6a1>] kernfs_find_ns+0x21/0x150
[  135.050999] PGD 220623067 PUD 222171067 PMD 0
[  135.055593] Oops: 0000 [#1] SMP
[  135.058938] Modules linked in: bnx2fc cnic uio fcoe libfcoe libfc 8021q mrp scsi_transport_fc garp scsi_tgt stp llc binfmt_misc dm_round_robin dm_multipath uinput iTCO_wdt iTCO_vendor_support microcode sg pcspkr serio_raw osst st(-) i2c_i801 lpc_ich mfd_core e1000e ptp pps_core ipmi_si ipmi_msghandler video tpm_infineon ext4(F) jbd2(F) mbcache(F) sd_mod(F) crc_t10dif(F) crct10dif_common(F) sr_mod(F) cdrom(F) pata_acpi(F) ata_generic(F) ata_piix(F) libata(F) mpt2sas(F) scsi_transport_sas(F) raid_class(F) ast(F) ttm(F) drm_kms_helper(F) drm(F) i2c_algo_bit(F) sysimgblt(F) sysfillrect(F) i2c_core(F) syscopyarea(F) dm_mirror(F) dm_region_hash(F) dm_log(F) dm_mod(F)
[  135.119686] CPU: 2 PID: 2028 Comm: rmmod Tainted: GF            3.14.0-rc1-linux-mainline+ #14
[  135.128453] Hardware name: wortmann To be filled by O.E.M./P8B-M Series, BIOS 6103 12/06/2012
[  135.137127] task: ffff880001de29d0 ti: ffff8802206e4000 task.ti: ffff8802206e4000
[  135.144742] RIP: 0010:[<ffffffff812af6a1>]  [<ffffffff812af6a1>] kernfs_find_ns+0x21/0x150
[  135.153148] RSP: 0018:ffff8802206e5c98  EFLAGS: 00010282
[  135.158562] RAX: ffff880001de29d0 RBX: 0000000000000000 RCX: 0000000000000006
[  135.165814] RDX: 0000000000000000 RSI: ffffffff817627e0 RDI: 0000000000000000
[  135.173040] RBP: ffff8802206e5cc8 R08: 0000000000000000 R09: 0000000000000001
[  135.180303] R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff817627e0
[  135.187554] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
[  135.194774] FS:  00007f817c720700(0000) GS:ffff880227200000(0000) knlGS:0000000000000000
[  135.202995] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  135.208878] CR2: 0000000000000098 CR3: 00000002219b0000 CR4: 00000000000407e0
[  135.216139] Stack:
[  135.218185]  ffffffff81af63a0 0000000000000000 ffffffff817627e0 0000000000000000
[  135.225783]  0000000000000000 0000000000000001 ffff8802206e5cf8 ffffffff812af8de
[  135.233347]  ffff880226801900 ffffffff81b43320 0000000000000000 ffff880221a7c1c0
[  135.240972] Call Trace:
[  135.243463]  [<ffffffff812af8de>] kernfs_find_and_get_ns+0x3e/0x70
[  135.249743]  [<ffffffff812ae27d>] sysfs_unmerge_group+0x1d/0x60
[  135.255716]  [<ffffffff81464da9>] pm_qos_sysfs_remove_latency+0x19/0x20
[  135.262430]  [<ffffffff81466a91>] dev_pm_qos_constraints_destroy+0x31/0x1e0
[  135.269500]  [<ffffffff81464de6>] dpm_sysfs_remove+0x16/0x50
[  135.275263]  [<ffffffff8145c077>] device_del+0x47/0x1e0
[  135.280554]  [<ffffffff8145c232>] device_unregister+0x22/0x60
[  135.286406]  [<ffffffffa02e23bd>] remove_cdevs+0x4d/0x90 [st]
[  135.292247]  [<ffffffffa02e78ff>] st_remove+0x3f/0xb0 [st]
[  135.297851]  [<ffffffff8145f39f>] __device_release_driver+0x7f/0xf0
[  135.304237]  [<ffffffff8145f4e8>] driver_detach+0xd8/0xe0
[  135.309722]  [<ffffffff8145e0fc>] bus_remove_driver+0x5c/0xd0
[  135.315553]  [<ffffffff81460170>] driver_unregister+0x30/0x70
[  135.321366]  [<ffffffffa02e97f4>] exit_st+0x5c/0x868 [st]
[  135.326861]  [<ffffffff8111b31a>] SyS_delete_module+0x19a/0x1f0
[  135.332891]  [<ffffffff810e336d>] ? trace_hardirqs_on+0xd/0x10
[  135.338811]  [<ffffffff81141974>] ? __audit_syscall_entry+0x94/0x100
[  135.345282]  [<ffffffff8135b1fe>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[  135.351806]  [<ffffffff816e8de9>] system_call_fastpath+0x16/0x1b
[  135.357859] Code: ff eb e3 0f 1f 80 00 00 00 00 55 48 89 e5 48 83 ec 30 48 89 5d d8 4c 89 65 e0 4c 89 6d e8 4c 89 75 f0 4c 89 7d f8 66 66 66 66 90 <44> 0f b7 bf 98 00 00 00 8b 05 71 6d 87 00 48 89 fb 49 89 f4 49
[  135.378282] RIP  [<ffffffff812af6a1>] kernfs_find_ns+0x21/0x150
[  135.384355]  RSP <ffff8802206e5c98>
[  135.387881] CR2: 0000000000000098
[  135.391298] ---[ end trace 1968409221ddb3c8 ]---
Signed-off-by: NMaurizio Lombardi <mlombard@redhat.com>
Acked-by: NKai Mäkisara <kai.makisara@kolumbus.fi>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This patch removes a bug in enlarge_buffer() that can make a
read or write fail under special conditions.

After changing TRY_DIRECT_IO to 0 and ST_MAX_SG to 32 in
st_options.h, a program that writes a first block of 128k and
than a second bigger block (e.g. 256k) fails. The second write
returns errno EOVERFLOW, as enlarge_buffer() checks the sg list
and detects that it already is full.
As enlarge_buffer uses different page allocation orders
depending on the size of the buffer needed, the check does not
make sense.
Signed-off-by: NBodo Stroesser <bstroesser@ts.fujitsu.com>
Acked-by: NKai Mäkisara <kai.makisara@kolumbus.fi>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The dev_attrs field of struct class is going away soon, dev_groups
should be used instead.  This converts the scsi tape class code to use
the correct field.

Cc: Kai Mäkisara <Kai.Makisara@kolumbus.fi>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This patch fixes a reference count bug in the SCSI tape driver which can be
reproduced with the following:

* Boot with slub_debug=FZPU, tape drive attached
* echo 1 > /sys/devices/... tape device pci path .../remove
* Wait for device removal
* echo 1 > /sys/kernel/slab/blkdev_queue/validate
* Slub debug complains about corrupted poison pattern

In commit 523e1d39 (block: make gendisk hold a reference to its queue)
add_disk() and disk_release() were modified to get/put an additional
reference on a disk queue to fix a reference counting discrepency
between bdev release and SCSI device removal.  The ST driver never
calls add_disk(), so this commit introduced an extra kref put when the
ST driver frees its struct gendisk.

Attempts were made to fix this bug at the block level [1] but later
abandoned due to floppy driver issues [2].

[1] https://lkml.org/lkml/2012/8/27/354
[2] https://lkml.org/lkml/2012/9/22/113Signed-off-by: NJoe Lawrence <joe.lawrence@stratus.com>
Tested-by: NEwan D. Milne <emilne@redhat.com>
Acked-by: NKai Mäkisara <Kai.Makisara@kolumbus.fi>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Convert to the much saner new idr interface.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The st_mutex was created when the BKL was removed, and
prevents simultaneous st_open calls. It is better to
protect just the necessary data.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NLee Duncan <lduncan@suse.com>
Acked-by: NKai Mäkisara <Kai.Makisara@kolumbus.fi>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>