Commit graph

13 commits

Author SHA1 Message Date
Alexey Dobriyan
99b7623380 proc 2/2: remove struct proc_dir_entry::owner
Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.

We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.

But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.

->read_proc/->write_proc were just fixed to not require ->owner for
protection.

rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.

Removing ->owner will also make PDE smaller.

So, let's nuke it.

Kudos to Jeff Layton for reminding about this, let's say, oversight.

http://bugzilla.kernel.org/show_bug.cgi?id=12454

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-03-31 01:14:44 +04:00
James Smart
315cb0ad12 [SCSI] scsi_host_lookup: error returns and NULL pointers
This patch cleans up the behavior of scsi_host_lookup().

The original implementation attempted to use the dual role of
either returning a pointer value, or a negative error code.
User's needed to use IS_ERR() to check the result. Additionally,
the IS_ERR() macro never checks for when a NULL pointer was
returned, so a NULL pointer actually passes with a success case.
Note: scsi_host_get(), used by scsi_host_lookup(), can return
a NULL pointer.

Talk about a mudhole for the unitiated to step into....

This patch converts scsi_host_lookup() to return either NULL
or a valid pointer. The consumers were updated for the change.

Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-03 11:46:12 -05:00
Harvey Harrison
cadbd4a5e3 [SCSI] replace __FUNCTION__ with __func__
[jejb: fixed up a ton of missed conversions.

 All of you are on notice this has happened, driver trees will now
 need to be rebased]

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: SCSI List <linux-scsi@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-27 10:31:49 -04:00
Denis V. Lunev
a973909fc3 scsi: use non-racy method for proc entries creation
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: Denis 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:21 -07:00
Hannes Reinecke
b0ed43360f [SCSI] add scsi_host and scsi_target to scsi_bus
This patch implements scsi_host and scsi_target device types
and adds both to the scsi_bus.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-22 15:16:29 -05:00
Rob Landley
eb44820c28 [SCSI] Add Documentation and integrate into docbook build
Add Documentation/DocBook/scsi_midlayer.tmpl, add to Makefile, and update
lots of kerneldoc comments in drivers/scsi/*.

Updated with comments from Stefan Richter, Stephen M. Cameron,
 James Bottomley and Randy Dunlap.

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:22:40 -06:00
Alan Stern
74feb53e8b [SCSI] scsi_proc.c: display sdev->scsi_level correctly
This patch (as833) fixes the "SCSI revision" output for
/proc/scsi/scsi.  If the scsi_level value is 0 (UNKNOWN), we want it
to show up as "0", not "ffffffff".

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-02-16 11:12:07 -06:00
Arjan van de Ven
00977a59b9 [PATCH] mark struct file_operations const 6
Many struct file_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:45 -08:00
Matthew Wilcox
4ff36718ed [SCSI] Improve inquiry printing
- Replace scsi_device_types array API with scsi_device_type function API.
   Gets rid of a lot of common code, as well as being easier to use.
 - Add the new device types in SPC4 r05a, and rename some of the older ones.
 - Reformat the printing of inquiry data; now fits on one line and
   includes PQ.

I think I've addressed all the feedback from the previous versions.  My
current test box prints:

scsi 2:0:1:0: Direct access     HP 18.2G ATLAS10K3_18_SCA HP05 PQ: 0 ANSI: 2

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-08-06 15:59:26 -05:00
James Bottomley
2ca48a1321 [SCSI] fix proc_scsi_write to return "length" on success with remove-single-device case
Problem spotted by: Suzuki K P <suzuki@in.ibm.com>

A zero return on success isn't correct for filesystem write functions.
They should either return negative error or the length of bytes
consumed.  Add code to convert our zero on success error return to
return the length of bytes passed in.

This fixes the following:

$ echo "scsi remove-single-device 0 0 3 0" > /proc/scsi/scsi
bash: echo: write error: No such device or address"

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-05-10 10:22:30 -05:00
Christoph Hellwig
e02f3f5922 [SCSI] remove target parent limitiation
When James Smart fixed the issue of the userspace scan atributes
crashing the system with the FC transport class he added a patch to
let the transport class check if the parent is valid for a given
transport class.

When adding support for the integrated raid of fusion sas devices
we ran into a problem with that, as it didn't allow adding virtual
raid volumes without the transport class knowing about it.

So this patch adds a user_scan attribute instead, that takes over from
scsi_scan_host_selected if the transport class sets it and thus lets
the transport class control the user-initiated scanning.  As this
plugs the hole about user-initiated scanning the target_parent hook
goes away and we rely on callers of the scanning routines to do
something sensible.

For SAS this meant I had to switch from a spinlock to a mutex to
synchronize the topology linked lists, in FC they were completely
unsynchronized which seems wrong.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-14 10:55:05 -06:00
Arjan van de Ven
0b95067238 [SCSI] turn most scsi semaphores into mutexes
the scsi layer is using semaphores in a mutex way, this patch converts
these into using mutexes instead

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-12 11:53:11 -06:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00