There is a race from when a device is created with device_create() and
then the drvdata is set with a call to dev_set_drvdata() in which a
sysfs file could be open, yet the drvdata will be NULL, causing all
sorts of bad things to happen.

This patch fixes the problem by using the new function,
device_create_drvdata().  It fixes the problem in all of the scsi
drivers that need it.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Use proc_create() to make sure that ->proc_fops be setup before gluing PDE to
main tree.

Add correct ->owner to proc_fops to fix reading/module unloading race.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It's big, but there doesn't seem to be a way to split it up smaller...
Signed-off-by: NTony Jones <tonyj@suse.de>
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since the SCSI layer uses the request queues from the block layer, blktrace can
also be used to trace the requests to all SCSI devices (like SCSI tape drives),
not only disks. The only missing part is the ioctl interface to start and stop
tracing.

This patch adds the SETUP, START, STOP and TEARDOWN ioctls from blktrace to the
sg device files. With this change, blktrace can be used for SCSI devices like
for disks, e.g.: blktrace -d /dev/sg1 -o - | blkparse -i -
Signed-off-by: NChristof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

The patch "[SCSI] sg: use idr to replace static arrays" in 2.6.24-rc1
causes a bogus line to appear in /proc/scsi/sg/devices containing
"-1 -1 -1 -1 -1 -1 -1 -1 -1" when there are no SCSI devices in the
system.  In 2.6.23, /proc/scsi/sg/devices is empty when there are no
SCSI devices in the system.  A similar problem exists with
/proc/scsi/sg/device_strs.  The following patch restores the behavior
of 2.6.23.
Signed-off-by: NTony Battersby <tonyb@cybernetics.com>
Acked-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

If cdev_add fails in sg_add, sg_remove crashes since class_data is
bogus.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

When I use cdparanoia my logs get spammed a lot by

printk: 464 messages suppressed.
sg_write: data in/out 30576/30576 bytes for SCSI command 0xbe--guessing data in;
   program cdparanoia not setting count and/or reply_len properly
printk: 1078 messages suppressed.

and many more of those. With this patch the message is only printed once
for a command in a row.

v1->v2: Prevent rate limit messages too (pointed out by jejb)
Signed-off-by: NAndi Kleen <ak@suse.de>
Acked-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

After turning on DEBUG_SG I hit a fail:

kernel BUG at include/linux/scatterlist.h:50!

	sg_build_indirect
	sg_build_reserve
	sg_open
	chrdev_open
	__dentry_open
	do_filp_open
	do_sys_open

We should initialise the sg list when we allocate it in sg_build_sgat.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Most drivers need to set length and offset as well, so may as well fold
those three lines into one.

Add sg_assign_page() for those two locations that only needed to set
the page, where the offset/length is set outside of the function context.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

sg uses a scheme to reallocate a single contiguous array of all its
pointers for lookup and management.  This didn't matter too much when sg
could only attach 256 nodes, but now the maximum has been bumped up to
32k we're starting to push the limits of the maximum allocatable
contiguous memory.  The solution to this is to eliminate the static
array and do everything via idr, which this patch does.
Acked-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

unsigned short is too small for sizeof(struct scatterlist) *
min(q->max_hw_segments, q->max_phys_segments).

This fixes memory leak with 4096 segments since 16 (likely sg size
with x86) * 4096 sets sglist_len to zero.

This might not happen without sg chaining support.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

coverity spotted this (cid #758).  All callers dereference sfp, so we dont
need this check.  In addition to this, we dereference it earlier in the
function.
Signed-off-by: NEric Sesterhenn <snakebyte@gmx.de>
Acked-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch (as857) modifies the SG_GET_RESERVED_SIZE and
SG_SET_RESERVED_SIZE ioctls in the sg driver, capping the values at
the device's request_queue's max_sectors value.  This will permit
cdrecord to obtain a legal value for the maximum transfer length,
fixing Bugzilla #7026.

The patch also caps the initial reserved_size value.  There's no
reason to have a reserved buffer larger than max_sectors, since it
would be impossible to use the extra space.

The corresponding ioctls in the block layer are modified similarly,
and the initial value for the reserved_size is set as large as
possible.  This will effectively make it default to max_sectors.
Note that the actual value is meaningless anyway, since block devices
don't have a reserved buffer.

Finally, the BLKSECTGET ioctl is added to sg, so that there will be a
uniform way for users to determine the actual max_sectors value for
any raw SCSI transport.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NJens Axboe <jens.axboe@oracle.com>
Acked-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

For certain LLDs the sg driver can cause on oops
when the transfer length is large and not a
multiple of PAGE_SIZE.

  ChangeLog:
    - correct the length of the last scatter gather
      list element.
    - fix some printk()s that have the wrong function
      name.
Signed-off-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This sg driver patch addresses the problem with larger
page sizes reported by Brian King in this post:
http://marc.theaimsgroup.com/?l=linux-scsi&m=115867718623631&w=2
Some other related matters are also addressed. Some of these
prevent oopses when the SG_SCATTER_SZ or scatter_elem_sz are
set to inappropriate values.

The scatter_elem_sz has been tested up to 4 MB which should
make the largest data transfer with one SCSI command, 32 MB
less one block, achievable with a relatively small number
of elements in the scatter gather list.

ChangeLog:
    - add scatter_elem_sz boot time parameter and sysfs module
      parameter that is initialized to SG_SCATTER_SZ
    - the driver will then adjust scatter_elem_sz to be the
      max(given(scatter_elem_sz), PAGE_SIZE)
      It will also round it up, if necessary, to be a power
      of two
    - clean up sg.h header, correct bad urls and some statements
      that are no longer valid
    - make the def_reserved_size sysfs module attribute writable
Signed-off-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

There's a problem where sg is executing a ->nopage operation on a
compound page, it actually calls get_page() on the first page in the
compound rather than the page which is being mapped.  The fix is to
select the correct page by indexing into the compound.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

I got a NULL derefrence in cdev_del+1 when called from sg_remove. By looking at
the code of sg_add, sg_alloc and sg_remove (all in drivers/scsi/sg.c) I found
out that sg_add is calling sg_alloc but if it fails afterwards it does not
deallocate the space that was allocated in sg_alloc and the redundant entry has
NULL in cdev. When sg_remove is being called, it tries to perform cdev_del to
this NULL cdev and fails.
Signed-off-by: NIshai Rabinovitz <ishai@mellanox.co.il>
Acked-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Signed-off-by: NJörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

Use ARRAY_SIZE macro instead of sizeof(x)/sizeof(x[0]) and remove
duplicates of the macro.
Signed-off-by: NTobias Klauser <tklauser@nuerscht.ch>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

when the sg driver is unable to setup direct IO, free that scatter
gather list prior to falling back to indirect IO

Further to this thread started by Bryan Holty:
http://marc.theaimsgroup.com/?l=linux-scsi&m=114306885116728&w=2

Here is the reworked patch again. This time it has been
tested with a program provided by Bryan.
Signed-off-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Doug found a bug where if scsi_execute_async fails, we are leaking
sg resources. scsi_do_req never failed so we did not have to handle
that case before.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

We currently have two implementations of this obsolete ioctl, one in
the block layer and one in the scsi code.  Both of them have drawbacks.

This patch kills the scsi layer version after updating the block version
with the missing bits:

 - argument checking
 - use scatterlist I/O
 - set number of retries based on the submitted command

This is the last user of non-S/G I/O except for the gdth driver, so
getting this in ASAP and through the scsi tree would be nie to kill
the non-S/G I/O path.  Jens, what do you think about adding a check
for non-S/G I/O in the midlayer?

Thanks to  Or Gerlitz for testing this patch.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

sg increments the refcount of constituent pages in its higher order memory
allocations when they are about to be mapped by userspace.  This is done so
the subsequent get_page/put_page when doing the mapping and unmapping does not
free the page.

Move over to the preferred way, that is, using compound pages instead.  This
fixes a whole class of possible obscure bugs where a get_user_pages on a
constituent page may outlast the user mappings or even the driver.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add device-major aliases in drivers/scsi, allowing kmod autoload:

MODULE_ALIAS_CHARDEV_MAJOR(SCSI_CHANGER_MAJOR)
MODULE_ALIAS_CHARDEV_MAJOR(OSST_MAJOR)
MODULE_ALIAS_CHARDEV_MAJOR(SCSI_TAPE_MAJOR)
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_CDROM_MAJOR)
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISKN_MAJOR)
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Acked-by: NKai Makisara <kai.makisara@kolumbus.fi>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

As devfs has been disabled from the kernel tree for a number of months
now (5 to be exact), here's a patch against 2.6.16-rc1-git1 that removes
support for it from the SCSI subsystem.

The patch also removes the scsi_disk devfs_name field as it's no longer
needed.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Change the core SCSI code to use kzalloc rather than kmalloc+memset
where possible.
Signed-off-by: NJes Sorensen <jes@sgi.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Remove a hack in the sg driver that alters the total buffer
length for SG_IO commands to ensure buffers are not odd byte
lengths. This breaks on the ipr driver since it requires the
request_bufflen to equal the length specified in the cdb.
The block layer SG_IO code does not appear to have this hack.
Signed-off-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

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

When the scsi_execute_async interface was added it ended up reducing
the flexibility of userspace to send arbitrary scsi commands through
sg using SG_IO. The SG_IO interface allows userspace to specify the
CDB length. This is now ignored in scsi_execute_async and it is
guessed using the COMMAND_SIZE macro, which is not always correct,
particularly for vendor specific commands. This patch adds a cmd_len
parameter to the scsi_execute_async interface to allow the caller
to specify the length of the CDB.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

sg_page_malloc should clear the data buffer, not that extent of mem_map.

This fixes Jesper's sg_page_free "Bad page states"
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Convert sg to always send scatterlists, and kill scsi_request usage.

TODO:

- move DIO code to common place or make block layers usable for ULDs.
- move buffer allocation code to common place for all ULDs to use. And
make buffer allocation code obey all queue limits so we can find
out about problems before calling scsi_execute_async. Currently, sg.c
could allocate a buffer that is too large, and send the request
to scsi_execute_async. scsi_execute_async will then check it against
all the queue limits and return a failure in this case. It would nicer
to know about the queue limit violation right away.
- move indirect (copy_to/from_user) paths commone place or make block
layers usable for ULDs.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

sg's st_map_user_pages is modelled on an earlier version of st's
sgl_map_user_pages, and has the same bug: if get_user_pages got some but
not all of the pages, then those got were released, but the positive res
code returned implied that they were still to be freed.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

2.6.15-rc1 made sg's st_unmap_user_pages and st's sgl_unmap_user_pages
BUG on a PageReserved page.  But that's wrong: they could be unmapping
the ZERO_PAGE, which is marked PG_reserved; and perhaps others (while
get_user_pages is still permitted on VM_PFNMAP areas - that may change).

More change is needed here: sg claims to dirty even pages written from,
and st claims not to dirty even pages read into; and SetPageDirty is not
adequate for this nowadays.  Fixes to those follow in a later patch: for
the moment just fix the 2.6.15 regression.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Acked-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This patch removes almost all inclusions of linux/version.h.  The 3
#defines are unused in most of the touched files.

A few drivers use the simple KERNEL_VERSION(a,b,c) macro, which is
unfortunatly in linux/version.h.

There are also lots of #ifdef for long obsolete kernels, this was not
touched.  In a few places, the linux/version.h include was move to where
the LINUX_VERSION_CODE was used.

quilt vi `find * -type f -name "*.[ch]"|xargs grep -El '(UTS_RELEASE|LINUX_VERSION_CODE|KERNEL_VERSION|linux/version.h)'|grep -Ev '(/(boot|coda|drm)/|~$)'`

search pattern:
/UTS_RELEASE\|LINUX_VERSION_CODE\|KERNEL_VERSION\|linux\/\(utsname\|version\).h
Signed-off-by: NOlaf Hering <olh@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This is the drivers/scsi/ part of the big kfree cleanup patch.

Remove pointless checks for NULL prior to calling kfree() in drivers/scsi/.
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Acked-by: NKai Makisara <kai.makisara@kolumbus.fi>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>