The current codebase makes use of the zero-length array language extension
to the C90 standard, but the preferred mechanism to declare variable-length
types such as these ones is a flexible array member[1][2], introduced in
C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by this
change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Link: https://lore.kernel.org/r/20200213000211.GA23171@embeddedor.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This topic branch covers a fundamental change in how our sg lists are
allocated to make mq more efficient by reducing the size of the
preallocated sg list. This necessitates a large number of driver
changes because the previous guarantee that if a driver specified
SG_ALL as the size of its scatter list, it would get a non-chained
list and didn't need to bother with scatterlist iterators is now
broken and every driver *must* use scatterlist iterators.
This was broken out as a separate topic because we need to convert all
the drivers before pulling the trigger and unconverted drivers kept
being found, necessitating a rebase.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-sg' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI scatter-gather list updates from James Bottomley:
"This topic branch covers a fundamental change in how our sg lists are
allocated to make mq more efficient by reducing the size of the
preallocated sg list.
This necessitates a large number of driver changes because the
previous guarantee that if a driver specified SG_ALL as the size of
its scatter list, it would get a non-chained list and didn't need to
bother with scatterlist iterators is now broken and every driver
*must* use scatterlist iterators.
This was broken out as a separate topic because we need to convert all
the drivers before pulling the trigger and unconverted drivers kept
being found, necessitating a rebase"
* tag 'scsi-sg' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (21 commits)
scsi: core: don't preallocate small SGL in case of NO_SG_CHAIN
scsi: lib/sg_pool.c: clear 'first_chunk' in case of no preallocation
scsi: core: avoid preallocating big SGL for data
scsi: core: avoid preallocating big SGL for protection information
scsi: lib/sg_pool.c: improve APIs for allocating sg pool
scsi: esp: use sg helper to iterate over scatterlist
scsi: NCR5380: use sg helper to iterate over scatterlist
scsi: wd33c93: use sg helper to iterate over scatterlist
scsi: ppa: use sg helper to iterate over scatterlist
scsi: pcmcia: nsp_cs: use sg helper to iterate over scatterlist
scsi: imm: use sg helper to iterate over scatterlist
scsi: aha152x: use sg helper to iterate over scatterlist
scsi: s390: zfcp_fc: use sg helper to iterate over scatterlist
scsi: staging: unisys: visorhba: use sg helper to iterate over scatterlist
scsi: usb: image: microtek: use sg helper to iterate over scatterlist
scsi: pmcraid: use sg helper to iterate over scatterlist
scsi: ipr: use sg helper to iterate over scatterlist
scsi: mvumi: use sg helper to iterate over scatterlist
scsi: lpfc: use sg helper to iterate over scatterlist
scsi: advansys: use sg helper to iterate over scatterlist
...
Unlike the legacy I/O path, scsi-mq preallocates a large array to hold
the scatterlist for each request. This static allocation can consume
substantial amounts of memory on modern controllers which support a
large number of concurrently outstanding requests.
To facilitate a switch to a smaller static allocation combined with a
dynamic allocation for requests that need it, we need to make sure all
SCSI drivers handle chained scatterlists correctly.
Convert remaining drivers that directly dereference the scatterlist
array to using the iterator functions.
[mkp: clarified commit message]
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The same effects can be achieved by setting the dma_boundary to
PAGE_SIZE - 1 and the max_segment_size to PAGE_SIZE, so shift those
settings into the drivers. Note that in many cases the setting might
be bogus, but this keeps the status quo.
[mkp: fix myrs and myrb]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Most SCSI drivers want to enable "clustering", that is merging of
segments so that they might span more than a single page. Remove the
ENABLE_CLUSTERING define, and require drivers to explicitly set
DISABLE_CLUSTERING to disable this feature.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/scsi/advansys.c: In function 'adv_isr_callback':
drivers/scsi/advansys.c:5952:6: warning:
variable 'srb_tag' set but not used [-Wunused-but-set-variable]
It never used since introduction in
commit 9c17c62aed ("advansys: use shared host tag map for command lookup")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Clang warns when multiple pairs of parentheses are used for a single
conditional statement.
drivers/scsi/advansys.c:6451:20: warning: equality comparison with
extraneous parentheses [-Wparentheses-equality]
if ((sdtr_data == 0xFF)) {
~~~~~~~~~~^~~~~~~
drivers/scsi/advansys.c:6451:20: note: remove extraneous parentheses
around the comparison to silence this warning
if ((sdtr_data == 0xFF)) {
~ ^ ~
drivers/scsi/advansys.c:6451:20: note: use '=' to turn this equality
comparison into an assignment
if ((sdtr_data == 0xFF)) {
^~
=
1 warning generated.
Link: https://github.com/ClangBuiltLinux/linux/issues/155
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
No functional change.
Just introduce scsi_host_busy() and replace the direct read of
scsi_host->host_busy with this new API.
Cc: Omar Sandoval <osandov@fb.com>,
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>,
Cc: James Bottomley <james.bottomley@hansenpartnership.com>,
Cc: Christoph Hellwig <hch@lst.de>,
Cc: Don Brace <don.brace@microsemi.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This will make subsequent refactoring easier to handle.
Note: this patch is nowhere checkpatch clean.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
gcc-7.0.1 now warns about a previously unnoticed access of uninitialized
struct members:
drivers/scsi/advansys.c: In function 'AscMsgOutSDTR':
drivers/scsi/advansys.c:3860:26: error: '*((void *)&sdtr_buf+5)' may be used uninitialized in this function [-Werror=maybe-uninitialized]
((ushort)s_buffer[i + 1] << 8) | s_buffer[i]);
^
drivers/scsi/advansys.c:3860:26: error: '*((void *)&sdtr_buf+7)' may be used uninitialized in this function [-Werror=maybe-uninitialized]
drivers/scsi/advansys.c:3860:26: error: '*((void *)&sdtr_buf+5)' may be used uninitialized in this function [-Werror=maybe-uninitialized]
drivers/scsi/advansys.c:3860:26: error: '*((void *)&sdtr_buf+7)' may be used uninitialized in this function [-Werror=maybe-uninitialized]
The code has existed in this exact form at least since v2.6.12, and the
warning seems correct. This uses named initializers to ensure we
initialize all members of the structure.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The advansys probe function tries to handle both ISA and PCI cases, each
hidden in an #ifdef when unused. This leads to a warning indicating that
when PCI is disabled we could be using uninitialized data:
drivers/scsi/advansys.c: In function advansys_board_found :
drivers/scsi/advansys.c:11036:5: error: ret may be used uninitialized in this function [-Werror=maybe-uninitialized]
drivers/scsi/advansys.c:10928:28: note: ret was declared here
drivers/scsi/advansys.c:11309:8: error: share_irq may be used uninitialized in this function [-Werror=maybe-uninitialized]
drivers/scsi/advansys.c:10928:6: note: share_irq was declared here
This cannot happen in practice because the hardware in question only
exists for PCI, but changing the code to just error out here is better
for consistency and avoids the warning.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Building the advansys driver in a big-endian configuration such as
ARM allmodconfig shows a warning:
drivers/scsi/advansys.c: In function 'adv_build_req':
include/uapi/linux/byteorder/big_endian.h:32:26: warning: large integer implicitly truncated to unsigned type [-Woverflow]
#define __cpu_to_le32(x) ((__force __le32)__swab32((x)))
drivers/scsi/advansys.c:7806:22: note: in expansion of macro 'cpu_to_le32'
scsiqp->sense_len = cpu_to_le32(SCSI_SENSE_BUFFERSIZE);
It turns out that the commit that introduced this used the cpu_to_le32()
incorrectly on an 8-bit field, which results in the sense_len to always
be set to zero, as the SCSI_SENSE_BUFFERSIZE value gets moved to upper
byte of the 32-bit intermediate.
This removes the cpu_to_le32() call to restore the original version.
I found this only by looking at the compiler output and have not done a
full review for possible further endianess bugs in the same driver.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 811ddc057a ("advansys: use DMA-API for mapping sense buffer")
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This patch changes the !blk-mq path to the same defaults as the blk-mq
I/O path by always enabling block tagging, and always using host wide
tags. We've had blk-mq available for a few releases so bugs with
this mode should have been ironed out, and this ensures we get better
coverage of over tagging setup over different configs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Fix compilation errors on forgotten #include <linux/dmapool.h> and warnings when
CONFIG_PCI is not set.
Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
The driver has now been converted to DMA-API, so we should
increase the version number and remove the compilation
warning.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Only required if the dma buffer has been allocated via
dma_alloc_noncoherent(), which this one is not.
With that call removed we can now also compile on ARM.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
We should be using spin_lock_irqsave() when within the
interrupt handler.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
DMA mapping might fail, so we need to check for errors here.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
These definitions are only ever used for the wide-scsi board,
so they should be prefixed with 'ADV', not 'ASC'.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Was uncommented in the original driver, and I'm too lazy to
figure out the conversion.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Removed unused structure ASC_SCSI_REQ_Q and update the
comments to 'ADV_SCSI_REQ_Q'.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
The 'data_addr' field is accessed by the board, and needs
to be kept in little endian format.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
AscIsrChipHalted will only ever return '0', so make it
a void function.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
The sg elements should be allocated from a dma pool.
And rename the structure to 'adv_sg_block' as they
are only used by the wide board.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Convert to use a shared host tag map for command lookup. This
saves us having an internal structure and avoid the command
pointer abuse.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
The advansys_reset() function is actually a host reset, not a
bus reset. And there is no need to have a 'last_reset'
value; the same value exists in struct Scsi_Host.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Using seq_putc to print a single character saves at least a strlen()
call and a memory access, and may also give a small .text reduction.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Consecutive seq_puts calls with literal strings may be replaced by a
single call, saving a little .text.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Using seq_printf to print a simple string is a lot more expensive than
it needs to be, since seq_puts exists. Replace seq_printf with
seq_puts when possible.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Christoph Hellwig <hch@lst.de>
For SPI drivers use the message definitions from scsi.h, and for target
drivers introduce a new TCM_*_TAG namespace.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com
Drop the now unused reason argument from the ->change_queue_depth method.
Also add a return value to scsi_adjust_queue_depth, and rename it to
scsi_change_queue_depth now that it can be used as the default
->change_queue_depth implementation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Remove the tagged argument from scsi_adjust_queue_depth, and just let it
handle the queue depth. For most drivers those two are fairly separate,
given that most modern drivers don't care about the SCSI "tagged" status
of a command at all, and many old drivers allow queuing of multiple
untagged commands in the driver.
Instead we start out with the ->simple_tags flag set before calling
->slave_configure, which is how all drivers actually looking at
->simple_tags except for one worke anyway. The one other case looks
broken, but I've kept the behavior as-is for now.
Except for that we only change ->simple_tags from the ->change_queue_type,
and when rejecting a tag message in a single driver, so keeping this
churn out of scsi_adjust_queue_depth is a clear win.
Now that the usage of scsi_adjust_queue_depth is more obvious we can
also remove all the trivial instances in ->slave_alloc or ->slave_configure
that just set it to the cmd_per_lun default.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Avoid taking the host-wide host_lock to check the per-host queue limit.
Instead we do an atomic_inc_return early on to grab our slot in the queue,
and if necessary decrement it after finishing all checks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
Now that we're using 64-bit LUNs internally we need to increase
the size of max_luns to 64 bits, too.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
asc_prt_line() had been hiding several places where formats had not
matched the argument types. The previous commit has finally made them
visible...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Gustavo A. R. Silva