Commit Graph

93 Commits

Author SHA1 Message Date
Linus Torvalds c596cc46ba scsi/gdth: fix crash in gdth_timeout if no gdth controllers found
If the gdth module is loaded (or compiled in), the gdth_timeout function
gets started even if no actual gdth controllers are found b the probing.

That ends up not only being unnecessary, but also causes a crash due to
the function blindly just trying to pick the first entry off the
"gdth_instances" list, and accessing it - which obviously doesn't work
if the list is empty!

Noticed by Ingo Molnar.

Tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-15 12:46:16 -07:00
Dhaval Giani c8e91b0a8f [SCSI] gdth: fix CONFIG_ISA build failure
drivers/scsi/gdth.c: In function ‘gdth_search_dev’:
drivers/scsi/gdth.c:646: warning: ‘pci_find_device’ is deprecated
(declared at include/linux/pci.h:482)
drivers/scsi/gdth.c: In function ‘gdth_init_isa’:
drivers/scsi/gdth.c:857: error: ‘gdth_irq_tab’ undeclared (first use in
this function)
drivers/scsi/gdth.c:857: error: (Each undeclared identifier is reported
only once
drivers/scsi/gdth.c:857: error: for each function it appears in.)
drivers/scsi/gdth.c: In function ‘gdth_copy_internal_data’:
drivers/scsi/gdth.c:2362: warning: unused variable ‘sg’

Looking into the code I notice that gdth_irq_tab is not declared with
CONFIG_ISA=y and !CONFIG_EISA.

The values seem to be same in 2.6.23 (I am not sure why it has been put
with #ifdefs in -mm) so I have just modified the #ifdef to take care of
CONFIG_ISA as well.

Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:56:24 -04:00
Boaz Harrosh 3892d88ae6 [SCSI] gdth: !use_sg cleanup and use of scsi accessors
gdth_execute() will issue an internal, none scsi-standard commands
onto __gdth_queuecommand(). Since it is not recommended to set
struct scsi_cmnd IO members in llds, gdth now uses internal IO
members for IO. In the case of gdth_execute() these members will be
set properly. In case the command was issued from scsi-ml
(by gdth_queuecommand) they will be set from scsi IO accessors.

  * define gdth IO accessors and use them throughout the driver.
  * use an sg-of-one in gdth_execute() and fix gdth_special_cmd()
    accordingly.
  * Clean the not use_sg code path and company

Signed-off-by Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:56:13 -04:00
Boaz Harrosh f842b64e0f [SCSI] gdth: Move members from SCp to gdth_cmndinfo, stage 2
- Cleanup the rest of the scsi_cmnd->SCp members and move them
    to gdth_cmndinfo:
    SCp.this_residual 	 => priority
    SCp.buffers_residual => timeout
    SCp.Status 		 => status and dma_dir
    SCp.Message 	 => info
    SCp.have_data_in 	 => volatile wait_for_completion
    SCp.sent_command 	 => OpCode
    SCp.phase 		 => phase

  - Two more members will be naturally removed in the !use_sg cleanup

  TODO: What is the meaning of gdth_cmndinfo.phase? (rhetorically)

Signed-off-by Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:56:09 -04:00
Boaz Harrosh 3058d5de47 [SCSI] gdth: Setup proper per-command private data
- scsi_cmnd and specifically ->SCp of, where heavily abused
    with internal meaning members and flags. So introduce a new
    struct gdth_cmndinfo, put it on ->host_scribble and define a
    gdth_cmnd_priv() accessor to retrieve it from a scsi_cmnd.

  - The structure now holds two members:
    internal_command - replaces the IS_GDTH_INTERNAL_CMD() croft.
    sense_paddr - which was a 64-bit spanning on 2 32-bit members of SCp.
    More overloaded members from SCp and scsi_cmnd will be moved in a later
    patch (For easy review).

  - Split up gdth_queuecommand to an additional internal_function. The later
    is the one called by gdth_execute(). This will be more evident later in
    the scsi accessors patch, but it also facilitates in the differentiation
    between internal_command and external. And the setup of gdth_cmndinfo of
    each command.

Signed-off-by Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:56:05 -04:00
Boaz Harrosh 884f7fba09 [SCSI] gdth: Remove gdth_ctr_tab[]
- Places like Initialization and Reset that Just loop on all devices can
    use the link list with the list_for_each_entry macro.
    But the io_ctrl from user mode now suffers performance-wise because
    code has to do a sequential search for the requested host number.
    I have isolated this search in a gdth_find_ha(int hanum) member
    for future enhancement if needed.

Signed-off-by Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:56:00 -04:00
Christoph Hellwig 835cc24aff [SCSI] gdth: switch to modern scsi host registration
- Use scsi_add_host and friends and track instances ourselves. And
    generally modernize the driver's structure.

  - TODO: Next we can remove the controller table
  - TODO: Fix use of deprecated pci_find_device()

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:55:55 -04:00
Boaz Harrosh 10e1b4bc92 [SCSI] gdth: gdth_interrupt() gdth_get_status() & gdth_wait() fixes
- gdth_get_status() returns a single device interrupt IStatus
  - gdth_interrupt split to __gdth_interrupt() that receives
    flags if is called from gdth_wait().
  - Use dev_id passed from kernel and do not loop on all
    controllers.
  - gdth_wait(), get read of all global variables and call the new
    __gdth_interrupt with these variables on the stack

Signed-off-by Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:55:51 -04:00
Boaz Harrosh 45f1a41b2b [SCSI] gdth: clean up host private data
- Based on same patch from Christoph Hellwig <hch@lst.de>

  - Get rid of all the indirection in the Scsi_Host private data and always
    put the gdth_ha_str directly into it.

  - Change all internal functions prototype to recieve an "gdth_ha_str *ha"
    pointer directlly and kill all that redundent access to the "gdth_ctr_tab[]"
    controller-table.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:55:46 -04:00
Christoph Hellwig 52759e6abc [SCSI] gdth: Remove virt hosts
The virt_ctr option allows to register a new scsi_host for each bus
on the raid controller.  This non-default option makes no sense with
the current scsi code and prevents cleaning up the host registration,
so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:55:42 -04:00
Jeff Garzik 69916b7cea [SCSI] gdth: Reorder scsi_host_template intitializers
shuffle scsi_host_template members such that they appear in the
order in which they are defined in the header.  this makes is easier
to verify when initializers are missing members.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:55:38 -04:00
Jeff Garzik a52667f3cd [SCSI] gdth: kill gdth_{read,write}[bwl] wrappers
They are direct equivalents to {read,write}[bwl].

Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:55:33 -04:00
Jeff Garzik 8d7a5da4fc [SCSI] gdth: Remove 2.4.x support, in-kernel changelog
* Remove in-source changelog.  It's archived permanently in git and
    various kernel archives, and changelogs should exist purely in git.

  * Remove 2.4.x kernel support.  It is an active obstacle to
    modernizing this driver, at this point.  This includes killing
    gdth_kcompat.h which is 100% redundant in modern kernels.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:55:29 -04:00
Christoph Hellwig 8514ef27ee [SCSI] gdth: split out pci probing
Split out per-device pci probing and put it under proper CONFIG_PCI.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:55:24 -04:00
Christoph Hellwig 706a5d4567 [SCSI] gdth: split out eisa probing
Split eisa probing into it's own helper, and do proper error unwinding.
Protect EISA probind by the proper CONFIG_EISA symbol.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:55:20 -04:00
Christoph Hellwig aed91cb520 [SCSI] gdth: split out isa probing
(note: this is ontop of Jeff's pci cleanup patch)

Split out isa probing into a helper of it's own.  Error handling is
cleaned up, but errors are not propagated yet.  Also enclose the isa
probe under the proper CONFIG_ISA symbol instead of the !IA64 hack.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:55:16 -04:00
Matthew Wilcox b8bff2aeaf gdth: Make one abuse of scsi_cmnd less obvious
Rather than having internal commands abuse scsi_done to call
  gdth_scsi_done, have all the places that use to call scsi_done directly
  call gdth_scsi_done, which now checks whether the command was internal,
  and calls scsi_done if not.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:55:11 -04:00
Matthew Wilcox 687d2bc487 [SCSI] gdth: Stop abusing ->done for internal commands
The ->done member was being used to mark commands as being internal.
I decided to put a magic number in ->underflow instead.  I believe this
to be safe as no current user of ->underflow has any of the bottom 9
bits set.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:52:41 -04:00
Mariusz Kozlowski bbfbbbc118 [SCSI] kmalloc + memset conversion to kzalloc
In NCR_D700, a4000t, aic7xxx_old, bvme6000, dpt_i2o, gdth, lpfc,
megaraid, mvme16x osst, pluto, qla2xxx, zorro7xx

Signed-off-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-10-12 14:41:00 -04:00
Jeff Garzik 8e9a8a0d56 [SCSI] gdth: remove redundant PCI stuff
This patch

* removes struct members that duplicate pci_dev members
* replaces ha->stype usage with ha->pdev->device usage where feasible

Signed-off-by: Jeff Garzik <jeff@garzik.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Achim Leubner <Achim_Leubner@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-07-31 10:36:30 -05:00
Robert P. J. Day 7a960b76ed [SCSI] gdth: Fix obvious typo "spin_lock_irqrestore()"
Fix misspelled "spin_lock_irqrestore" to read "spin_unlock_irqrestore"
instead.

Presumably, GDTH_RTC doesn't get used a lot.

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Acked-by: Achim Leubner <achim_leubner@adaptec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-05-30 08:39:52 -05:00
David Rientjes 6c4b7e4fdf [SCSI] gdth: fix ambiguous gdthtable definition
Labeling a variable as __attribute_used__ is ambiguous: it means
__attribute__((unused)) for gcc <3.4 and __attribute__((used)) for gcc >=3.4.
There is no such thing as labeling a variable as __attribute__((used)).  We
assume that we're simply suppressing a warning here if gdthtable[] is declared
but unreferenced.

Acked-by: Achim Leubner <achim_leubner@adaptec.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-05-30 08:39:16 -05:00
Joerg Dorchain bb9ba31ca3 [SCSI] gdth: fix oops in gdth_copy_cmd()
Recent alterations to the gdth_fill_raw_cmd() path no longer set the
sg_ranz field for zero transfer commands. However, this field is used
lower down in the function to initialise ha->cmd_len to the size of
the firmware packet.  If this uninitialised field contains a bogus
value, ha->cmd_len can become much larger than the actual firmware
packet and end up oopsing in gdth_copy_cmd() as it tries to copy this
huge packet to the device (usually because it runs into an unallocated
page).

The fix is to initialise the sg_ranz field to zero at the start of
gdth_fill_raw_cmd().

Signed-off-by: Joerg Dorchain <joerg@dorchain.net>
Acked-by: "Leubner, Achim" <Achim_Leubner@adaptec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-03-11 10:58:49 -05:00
Tim Schmielau cd354f1ae7 [PATCH] remove many unneeded #includes of sched.h
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there.  Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.

To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.

Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm.  I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).

Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-14 08:09:54 -08:00
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
Jean Delvare 107e716b34 [SCSI] gdth: Fix && typos
Fix uses of "&&" where "&" was obviously intended instead.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-11-10 09:59:49 +09:00
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00
Peter Zijlstra 6e9a4738c9 [PATCH] completions: lockdep annotate on stack completions
All on stack DECLARE_COMPLETIONs should be replaced by:
DECLARE_COMPLETION_ONSTACK

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:24 -07:00
Thomas Gleixner 1d6f359a2e [PATCH] irq-flags: scsi: Use the new IRQF_ constants
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 13:58:53 -07:00
Christoph Hellwig beb4048750 [SCSI] remove scsi_request infrastructure
With Achim patch the last user (gdth) is switched away from scsi_request
so we an kill it now.  Also disables some code in i2o_scsi that was
broken since the sg driver stopped using scsi_requests.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-06-10 16:24:40 -05:00
Tobias Klauser 6391a11375 [SCSI] drivers/scsi: Use ARRAY_SIZE macro
Use ARRAY_SIZE macro instead of sizeof(x)/sizeof(x[0]) and remove
duplicates of the macro.

Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-06-10 10:45:30 -05:00
Leubner, Achim cbd5f69b98 [SCSI] remove the scsi_request interface from the gdth driver
Initial pass at converting the gdth driver away from the scsi_request
interface so that the request interface can be removed post 2.6.18
without breaking gdth.  Based on changes from Christoph Hellwig
<hch@lst.de>

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-06-10 10:24:40 -05:00
Christoph Hellwig 5d5ff44fe6 [SCSI] fix up request buffer reference in various scsi drivers
Various scsi drivers use scsi_cmnd.buffer and scsi_cmnd.bufflen in their
queuecommand functions.  Those fields are internal storage for the
midlayer only and are used to restore the original payload after
request_buffer and request_bufflen have been overwritten for EH.  Using
the buffer and bufflen fields means they do very broken things in error
handling.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-06-06 11:07:25 -04:00
Matthias Gehre 910638ae7e [PATCH] Replace 0xff.. with correct DMA_xBIT_MASK
Replace all occurences of 0xff..  in calls to function pci_set_dma_mask()
and pci_set_consistant_dma_mask() with the corresponding DMA_xBIT_MASK from
linux/dma-mapping.h.

Signed-off-by: Matthias Gehre <M.Gehre@gmx.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 09:16:07 -08:00
Alan Stern e041c68341 [PATCH] Notifier chain update: API changes
The kernel's implementation of notifier chains is unsafe.  There is no
protection against entries being added to or removed from a chain while the
chain is in use.  The issues were discussed in this thread:

    http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2

We noticed that notifier chains in the kernel fall into two basic usage
classes:

	"Blocking" chains are always called from a process context
	and the callout routines are allowed to sleep;

	"Atomic" chains can be called from an atomic context and
	the callout routines are not allowed to sleep.

We decided to codify this distinction and make it part of the API.  Therefore
this set of patches introduces three new, parallel APIs: one for blocking
notifiers, one for atomic notifiers, and one for "raw" notifiers (which is
really just the old API under a new name).  New kinds of data structures are
used for the heads of the chains, and new routines are defined for
registration, unregistration, and calling a chain.  The three APIs are
explained in include/linux/notifier.h and their implementation is in
kernel/sys.c.

With atomic and blocking chains, the implementation guarantees that the chain
links will not be corrupted and that chain callers will not get messed up by
entries being added or removed.  For raw chains the implementation provides no
guarantees at all; users of this API must provide their own protections.  (The
idea was that situations may come up where the assumptions of the atomic and
blocking APIs are not appropriate, so it should be possible for users to
handle these things in their own way.)

There are some limitations, which should not be too hard to live with.  For
atomic/blocking chains, registration and unregistration must always be done in
a process context since the chain is protected by a mutex/rwsem.  Also, a
callout routine for a non-raw chain must not try to register or unregister
entries on its own chain.  (This did happen in a couple of places and the code
had to be changed to avoid it.)

Since atomic chains may be called from within an NMI handler, they cannot use
spinlocks for synchronization.  Instead we use RCU.  The overhead falls almost
entirely in the unregister routine, which is okay since unregistration is much
less frequent that calling a chain.

Here is the list of chains that we adjusted and their classifications.  None
of them use the raw API, so for the moment it is only a placeholder.

  ATOMIC CHAINS
  -------------
arch/i386/kernel/traps.c:		i386die_chain
arch/ia64/kernel/traps.c:		ia64die_chain
arch/powerpc/kernel/traps.c:		powerpc_die_chain
arch/sparc64/kernel/traps.c:		sparc64die_chain
arch/x86_64/kernel/traps.c:		die_chain
drivers/char/ipmi/ipmi_si_intf.c:	xaction_notifier_list
kernel/panic.c:				panic_notifier_list
kernel/profile.c:			task_free_notifier
net/bluetooth/hci_core.c:		hci_notifier
net/ipv4/netfilter/ip_conntrack_core.c:	ip_conntrack_chain
net/ipv4/netfilter/ip_conntrack_core.c:	ip_conntrack_expect_chain
net/ipv6/addrconf.c:			inet6addr_chain
net/netfilter/nf_conntrack_core.c:	nf_conntrack_chain
net/netfilter/nf_conntrack_core.c:	nf_conntrack_expect_chain
net/netlink/af_netlink.c:		netlink_chain

  BLOCKING CHAINS
  ---------------
arch/powerpc/platforms/pseries/reconfig.c:	pSeries_reconfig_chain
arch/s390/kernel/process.c:		idle_chain
arch/x86_64/kernel/process.c		idle_notifier
drivers/base/memory.c:			memory_chain
drivers/cpufreq/cpufreq.c		cpufreq_policy_notifier_list
drivers/cpufreq/cpufreq.c		cpufreq_transition_notifier_list
drivers/macintosh/adb.c:		adb_client_list
drivers/macintosh/via-pmu.c		sleep_notifier_list
drivers/macintosh/via-pmu68k.c		sleep_notifier_list
drivers/macintosh/windfarm_core.c	wf_client_list
drivers/usb/core/notify.c		usb_notifier_list
drivers/video/fbmem.c			fb_notifier_list
kernel/cpu.c				cpu_chain
kernel/module.c				module_notify_list
kernel/profile.c			munmap_notifier
kernel/profile.c			task_exit_notifier
kernel/sys.c				reboot_notifier_list
net/core/dev.c				netdev_chain
net/decnet/dn_dev.c:			dnaddr_chain
net/ipv4/devinet.c:			inetaddr_chain

It's possible that some of these classifications are wrong.  If they are,
please let us know or submit a patch to fix them.  Note that any chain that
gets called very frequently should be atomic, because the rwsem read-locking
used for blocking chains is very likely to incur cache misses on SMP systems.
(However, if the chain's callout routines may sleep then the chain cannot be
atomic.)

The patch set was written by Alan Stern and Chandra Seetharaman, incorporating
material written by Keith Owens and suggestions from Paul McKenney and Andrew
Morton.

[jes@sgi.com: restructure the notifier chain initialization macros]
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:50 -08:00
Jenx Axboe 40cdc840dc [SCSI] gdth: don't map zero-length requests
Don't map zero-length requests in gdth, zome architectures don't like
that in their dma mapping routines.

[ I'm pretty sure Jens posted this before, but for some reason it got
  forgotten  --hch ]

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-02-05 12:59:29 -06:00
Adrian Bunk 575c968718 spelling: s/appropiate/appropriate/
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-01-15 02:00:17 +01:00
Christoph Hellwig f64a181d89 [SCSI] remove Scsi_Device typedef
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-11-09 15:48:20 -05:00
Christoph Hellwig d0be4a7d29 [SCSI] remove Scsi_Host_Template typedef
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-11-09 15:44:09 -05:00
Christoph Hellwig 12413197ee [SCSI] remove scsi_set_device
scsi_add_host is the proper place to set the device, but people copy
the scsi_set_device usage from older drivers again and again.

note that this leaves some legacy drivers like qlogicisp/qlogicfc
without pci association in sysfs, but they're scheduled to go away soon
anyway.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-06-26 08:31:47 -05:00
Jeff Garzik 3471c28803 [SCSI] Remove no-op implementations of SCSI EH hooks
Drivers need not implement a hook that returns FAILED, and does nothing
else, since the SCSI midlayer code will do that for us.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-06-17 12:04:45 -05:00
8e8790415e [PATCH] drivers/scsi/gdth.c: cleanups
This patch contains the following cleanups:
- make some needlessly global functions static
- remove one more kernel 2.2 #ifdef

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-04-18 13:50:23 -05:00
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