commit 759e8756da00aa115d504a18155b1d1ee1cc12e8 upstream.

The ACS specification does not allow a non-NCQ command to be issued while
an NCQ command is outstanding.

Commit 0ea84089dbf6 ("ata: libata-scsi: avoid Non-NCQ command starvation")
introduced a feature where a deferred non-NCQ command gets issued from a
workqueue. The design stores a single non-NCQ command per port.

However, when using Port Multipliers (PMPs), specifically PMPs that
support FIS-Based Switching (FBS), non-NCQ and NCQ commands can be mixed
on the same port, just not for the same link, see e.g. ata_std_qc_defer()
which is, and always has operated on a per-link basis.

Therefore, move the deferred_qc from struct ata_port to struct ata_link.
This way, when using a PMP with FBS, we will not needlessly defer commands
to all other links, just because one link issued a non-NCQ command while
having an NCQ command outstanding. Only commands for that specific link
will be deferred. This is in line with how PMPs with FBS worked before
commit 0ea84089dbf6 ("ata: libata-scsi: avoid Non-NCQ command starvation").

Fixes: 0ea84089dbf6 ("ata: libata-scsi: avoid Non-NCQ command starvation")
Tested-by: Tommy Kelly <linux@tkel.ly>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit f233124fb36cd57ef09f96d517a38ab4b902e15e upstream.

When using Port Multipliers (PMPs) with Command-Based Switching (CBS), you
can only issue commands to one link at a time. For PMPs with CBS, there is
already code to handle commands being sent to different links in
sata_pmp_qc_defer_cmd_switch() using ap->excl_link. sata_sil24 also makes
use of ap->excl_link.

A user on the list reported that commit 0ea84089dbf6 ("ata: libata-scsi:
avoid Non-NCQ command starvation") broke PMPs with CBS. The commit
introduced code that stores a deferred qc in ap->deferred_qc, to later be
issued via a workqueue. It turns out that this change is incompatible with
the existing ap->excl_link handling used by PMPs with CBS.

Thus, modify sata_pmp_qc_defer_cmd_switch() and sil24_qc_defer() to return
ATA_DEFER_LINK_EXCL, and make sure that the deferred QC handling via
workqueue is not used for this return value.

This way, PMPs with CBS will work once again. Note that the starvation
referenced in commit 0ea84089dbf6 ("ata: libata-scsi: avoid Non-NCQ
command starvation") can only happen on libsas ports, and libsas does not
support Port Multipliers, thus there is no harm of reverting back to the
previous way of deferring commands for PMPs with CBS.

Non-libsas ports connected to anything but a PMP with CBS (e.g. a normal
drive or a PMP with FBS) will continue using the deferred workqueue, since
it does result in lower completion latencies for non-NCQ commands, even
though the workqueue is not strictly needed to avoid starvation for
non-libsas ports.

If we want to modify the scope of the workqueue issuing to also handle
PMPs with CBS, then we should ensure that we can save both NCQ and non-NCQ
commands in ap->deferred_qc, while also removing the existing PMP CBS
handling using ap->excl_link, such that we don't duplicate features.

While at it, also add a comment explaining how the ap->excl_link mechanism
works.

Fixes: 0ea84089dbf6 ("ata: libata-scsi: avoid Non-NCQ command starvation")
Tested-by: Tommy Kelly <linux@tkel.ly>
Reported-by: Tommy Kelly <linux@tkel.ly>
Closes: https://lore.kernel.org/linux-ide/ce09cc21-a8e9-4845-b205-35411e22fba9@tkel.ly/
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>

Introduce struct ata_reset_operations to aggregate in a single structure
the definitions of the 4 reset methods (prereset, softreset, hardreset
and postreset) for a port. This new structure is used in struct ata_port
to define the reset methods for a regular port (reset field) and for a
port-multiplier port (pmp_reset field). A pointer to either of these
fields replaces the 4 reset method arguments passed to ata_eh_recover()
and ata_eh_reset().

The definition of the reset methods for all drivers is changed to use
the reset and pmp_reset fields in struct ata_port_operations.

A large number of files is modifed, but no functional changes are
introduced.

Suggested-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20250716020315.235457-3-dlemoal@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>

The 512B buffer sector_buf field of struct ata_port is used for scanning
devices as well as during error recovery with ata EH. This buffer is
thus useless if a port does not have a device connected to it.
And also given that commands using this buffer are issued to devices,
and not to ports, move this buffer definition from struct ata_port to
struct ata_device.

This change slightly increases system memory usage for systems using a
port-multiplier as in that case we do not need a per-device buffer for
scanning devices (PMP does not allow parallel scanning) nor for EH (as
when entering EH we are guaranteed that all commands to all devices
connected to the PMP have completed or have been aborted). However,
this change reduces memory usage on systems that have many ports with
only few devices rives connected, which is a much more common use case
than the PMP use case.

Suggested-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Niklas Cassel <cassel@kernel.org>

Add tracepoints for ATA error handling.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

Fixes the following W=1 kernel build warning(s):

 drivers/ata/libata-pmp.c:76: warning: Function parameter or member 'val' not described in 'sata_pmp_write'
 drivers/ata/libata-pmp.c:76: warning: Excess function parameter 'r_val' description in 'sata_pmp_write'

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Tejun Heo <teheo@suse.de>
Cc: linux-ide@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

During system resume from suspend, this can be observed on ASM1062 PMP
controller:

ata10.01: SATA link down (SStatus 0 SControl 330)
ata10.02: hard resetting link
ata10.02: SATA link down (SStatus 0 SControl 330)
ata10.00: configured for UDMA/133
Kernel panic - not syncing: stack-protector: Kernel
 in: sata_pmp_eh_recover+0xa2b/0xa40

CPU: 2 PID: 230 Comm: scsi_eh_9 Tainted: P OE
#49-Ubuntu
Hardware name: System manufacturer System Product
 1001 12/10/2017
Call Trace:
dump_stack+0x63/0x8b
panic+0xe4/0x244
? sata_pmp_eh_recover+0xa2b/0xa40
__stack_chk_fail+0x19/0x20
sata_pmp_eh_recover+0xa2b/0xa40
? ahci_do_softreset+0x260/0x260 [libahci]
? ahci_do_hardreset+0x140/0x140 [libahci]
? ata_phys_link_offline+0x60/0x60
? ahci_stop_engine+0xc0/0xc0 [libahci]
sata_pmp_error_handler+0x22/0x30
ahci_error_handler+0x45/0x80 [libahci]
ata_scsi_port_error_handler+0x29b/0x770
? ata_scsi_cmd_error_handler+0x101/0x140
ata_scsi_error+0x95/0xd0
? scsi_try_target_reset+0x90/0x90
scsi_error_handler+0xd0/0x5b0
kthread+0x121/0x140
? scsi_eh_get_sense+0x200/0x200
? kthread_create_worker_on_cpu+0x70/0x70
ret_from_fork+0x22/0x40
Kernel Offset: 0xcc00000 from 0xffffffff81000000
(relocation range: 0xffffffff80000000-0xffffffffbfffffff)

Since sata_pmp_eh_recover_pmp() doens't set rc when ATA_DFLAG_DETACH is
set, sata_pmp_eh_recover() continues to run. During retry it triggers
the stack protector.

Set correct rc in sata_pmp_eh_recover_pmp() to let sata_pmp_eh_recover()
jump to pmp_fail directly.

BugLink: https://bugs.launchpad.net/bugs/1821434
Cc: stable@vger.kernel.org
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Based on 1 normalized pattern(s):

  this file is released under the gplv2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 68 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190114.292346262@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>