* [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
@ 2019-02-21 12:11 Sreekanth Reddy
[not found] ` <20190222152433.CF1822086A@mail.kernel.org>
2019-02-25 19:08 ` Hannes Reinecke
0 siblings, 2 replies; 13+ messages in thread
From: Sreekanth Reddy @ 2019-02-21 12:11 UTC (permalink / raw)
To: linux-scsi
Cc: Sathya.Prakash, suganath-prabu.subramani, Sreekanth Reddy, stable
During expander reset handling, the driver invokes kernel function
scsi_host_find_tag() to obtain outstanding requests associated with
the scsi host managed by the driver. Kernel’s block layer may return
stale entry for one or more outstanding requests if blk-mq is enabled.
This may lead to Kernel panic if the returned value is inaccessible or
the memory pointed by the returned value is reused.
Reference of upstream discussion -
https://patchwork.kernel.org/patch/10734933/
So to fix this issue, driver will use scsi lookup table to track
outstanding IOs at driver level and it avoids using scsi_host_find_tag().
Have done following changes in this patch,
* Allocated & initialized scsi_lookup table of type
(struct scsiio_tracker) and of depth host's can_queue at driver load time
and it will be deallocated at driver unload time.
* Once scmd is received, driver will take scsiio_tracker at entry
corresponding to scmd's tag value from scsi_lookup table. Then this
scsiio_tracker entry is initialized with proper smid, scmd, cb_idx etc.
And this scsiio_tracker entry contents are cleared before driver
calling scsi_done callback function.
* scmd's host_scribble variable is used to save the corresponding
scsiio_tracker address, later at any time driver can easily retrieve the
scmd's corresponding scsiio_tacker using this host_scribble variable.
* Whenever driver wants to get the outstanding IOs at the driver level
then driver can go through this scsi_lookup table and if it observe
any entry with non-null scmd then it means that scmd is outstanding
at the driver level.
v1 change set:
Updated the patch description.
Cc: <stable@vger.kernel.org>
Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
---
drivers/scsi/mpt3sas/mpt3sas_base.c | 45 +++++++++++++++++++++++++++++---
drivers/scsi/mpt3sas/mpt3sas_base.h | 10 +++++++
drivers/scsi/mpt3sas/mpt3sas_ctl.c | 2 +-
drivers/scsi/mpt3sas/mpt3sas_scsih.c | 16 +++++-------
drivers/scsi/mpt3sas/mpt3sas_warpdrive.c | 2 +-
5 files changed, 60 insertions(+), 15 deletions(-)
diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
index 0a6cb8f..8e3d0d5 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
@@ -1301,7 +1301,7 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
cmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
if (cmd)
- return scsi_cmd_priv(cmd);
+ return mpt3sas_get_st_from_scmd(cmd);
return NULL;
}
@@ -1709,7 +1709,7 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
struct scsi_cmnd *scmd)
{
struct chain_tracker *chain_req;
- struct scsiio_tracker *st = scsi_cmd_priv(scmd);
+ struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
u16 smid = st->smid;
u8 chain_offset =
atomic_read(&ioc->chain_lookup[smid - 1].chain_offset);
@@ -3203,14 +3203,18 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
mpt3sas_base_get_smid_scsiio(struct MPT3SAS_ADAPTER *ioc, u8 cb_idx,
struct scsi_cmnd *scmd)
{
- struct scsiio_tracker *request = scsi_cmd_priv(scmd);
+ struct scsiio_tracker *request;
unsigned int tag = scmd->request->tag;
u16 smid;
+ scmd->host_scribble = (unsigned char *)(&ioc->scsi_lookup[tag]);
+ request = mpt3sas_get_st_from_scmd(scmd);
+
smid = tag + 1;
request->cb_idx = cb_idx;
request->msix_io = _base_get_msix_index(ioc);
request->smid = smid;
+ request->scmd = scmd;
INIT_LIST_HEAD(&request->chain_list);
return smid;
}
@@ -3264,6 +3268,7 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
return;
st->cb_idx = 0xFF;
st->direct_io = 0;
+ st->scmd = NULL;
atomic_set(&ioc->chain_lookup[st->smid - 1].chain_offset, 0);
st->smid = 0;
}
@@ -4252,6 +4257,11 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
ioc->config_page, ioc->config_page_dma);
}
+ if (ioc->scsi_lookup) {
+ free_pages((ulong)ioc->scsi_lookup, ioc->scsi_lookup_pages);
+ ioc->scsi_lookup = NULL;
+ }
+
kfree(ioc->hpr_lookup);
kfree(ioc->internal_lookup);
if (ioc->chain_lookup) {
@@ -4377,6 +4387,7 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
max_request_credit = min_t(u16, facts->RequestCredit,
MAX_HBA_QUEUE_DEPTH);
+retry:
/* Firmware maintains additional facts->HighPriorityCredit number of
* credits for HiPriprity Request messages, so hba queue depth will be
* sum of max_request_credit and high priority queue depth.
@@ -4581,9 +4592,29 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
(unsigned long long)ioc->request_dma));
total_sz += sz;
+ sz = ioc->shost->can_queue * sizeof(struct scsiio_tracker);
+ ioc->scsi_lookup_pages = get_order(sz);
+ ioc->scsi_lookup = (struct scsiio_tracker *)__get_free_pages(
+ GFP_KERNEL, ioc->scsi_lookup_pages);
+ if (!ioc->scsi_lookup) {
+ /* Retry allocating memory by reducing the queue depth */
+ if ((max_request_credit - 64) >
+ (ioc->internal_depth + INTERNAL_SCSIIO_CMDS_COUNT)) {
+ max_request_credit -= 64;
+ _base_release_memory_pools(ioc);
+ goto retry;
+ } else {
+ ioc_err(ioc,
+ "scsi_lookup: get_free_pages failed, sz(%d)\n",
+ (int)sz);
+ goto out;
+ }
+ }
+
dinitprintk(ioc,
ioc_info(ioc, "scsiio(0x%p): depth(%d)\n",
ioc->request, ioc->scsiio_depth));
+ total_sz += sz;
ioc->chain_depth = min_t(u32, ioc->chain_depth, MAX_CHAIN_DEPTH);
sz = ioc->scsiio_depth * sizeof(struct chain_lookup);
@@ -6239,6 +6270,14 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
+ smid = 1;
+ for (i = 0; i < ioc->shost->can_queue; i++, smid++) {
+ ioc->scsi_lookup[i].cb_idx = 0xFF;
+ ioc->scsi_lookup[i].smid = smid;
+ ioc->scsi_lookup[i].scmd = NULL;
+ ioc->scsi_lookup[i].direct_io = 0;
+ }
+
/* hi-priority queue */
INIT_LIST_HEAD(&ioc->hpr_free_list);
smid = ioc->hi_priority_smid;
diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h
index 19158cb..f8c82f6 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.h
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.h
@@ -816,6 +816,7 @@ struct chain_lookup {
/**
* struct scsiio_tracker - scsi mf request tracker
* @smid: system message id
+ * @scmd: scsi request pointer
* @cb_idx: callback index
* @direct_io: To indicate whether I/O is direct (WARPDRIVE)
* @chain_list: list of associated firmware chain tracker
@@ -823,6 +824,7 @@ struct chain_lookup {
*/
struct scsiio_tracker {
u16 smid;
+ struct scsi_cmnd *scmd;
u8 cb_idx;
u8 direct_io;
struct pcie_sg_list pcie_sg_list;
@@ -830,6 +832,12 @@ struct scsiio_tracker {
u16 msix_io;
};
+static inline struct scsiio_tracker *
+mpt3sas_get_st_from_scmd(struct scsi_cmnd *scmd)
+{
+ return (struct scsiio_tracker *)scmd->host_scribble;
+}
+
/**
* struct request_tracker - firmware request tracker
* @smid: system message id
@@ -1296,6 +1304,8 @@ struct MPT3SAS_ADAPTER {
u8 *request;
dma_addr_t request_dma;
u32 request_dma_sz;
+ struct scsiio_tracker *scsi_lookup;
+ ulong scsi_lookup_pages;
struct pcie_sg_list *pcie_sg_lookup;
spinlock_t scsi_lookup_lock;
int pending_io_count;
diff --git a/drivers/scsi/mpt3sas/mpt3sas_ctl.c b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
index b2bb47c..ad43e60 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
@@ -595,7 +595,7 @@ void mpt3sas_ctl_reset_done_handler(struct MPT3SAS_ADAPTER *ioc)
continue;
if (priv_data->sas_target->handle != handle)
continue;
- st = scsi_cmd_priv(scmd);
+ st = mpt3sas_get_st_from_scmd(scmd);
tm_request->TaskMID = cpu_to_le16(st->smid);
found = 1;
}
diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
index 8bb5b8f..86d0e3c 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
@@ -1465,11 +1465,9 @@ struct scsi_cmnd *
if (smid > 0 &&
smid <= ioc->scsiio_depth - INTERNAL_SCSIIO_CMDS_COUNT) {
- u32 unique_tag = smid - 1;
-
- scmd = scsi_host_find_tag(ioc->shost, unique_tag);
+ scmd = ioc->scsi_lookup[smid - 1].scmd;
if (scmd) {
- st = scsi_cmd_priv(scmd);
+ st = mpt3sas_get_st_from_scmd(scmd);
if (st->cb_idx == 0xFF || st->smid == 0)
scmd = NULL;
}
@@ -2819,7 +2817,7 @@ int mpt3sas_scsih_issue_locked_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle,
{
struct MPT3SAS_ADAPTER *ioc = shost_priv(scmd->device->host);
struct MPT3SAS_DEVICE *sas_device_priv_data;
- struct scsiio_tracker *st = scsi_cmd_priv(scmd);
+ struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
u16 handle;
int r;
@@ -4466,7 +4464,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
continue;
count++;
_scsih_set_satl_pending(scmd, false);
- st = scsi_cmd_priv(scmd);
+ st = mpt3sas_get_st_from_scmd(scmd);
mpt3sas_base_clear_st(ioc, st);
scsi_dma_unmap(scmd);
if (ioc->pci_error_recovery || ioc->remove_host)
@@ -5193,7 +5191,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
* WARPDRIVE: If direct_io is set then it is directIO,
* the failed direct I/O should be redirected to volume
*/
- st = scsi_cmd_priv(scmd);
+ st = mpt3sas_get_st_from_scmd(scmd);
if (st->direct_io &&
((ioc_status & MPI2_IOCSTATUS_MASK)
!= MPI2_IOCSTATUS_SCSI_TASK_TERMINATED)) {
@@ -7335,7 +7333,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
scmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
if (!scmd)
continue;
- st = scsi_cmd_priv(scmd);
+ st = mpt3sas_get_st_from_scmd(scmd);
sdev = scmd->device;
sas_device_priv_data = sdev->hostdata;
if (!sas_device_priv_data || !sas_device_priv_data->sas_target)
@@ -10176,7 +10174,6 @@ static void pcie_device_make_active(struct MPT3SAS_ADAPTER *ioc,
.shost_attrs = mpt3sas_host_attrs,
.sdev_attrs = mpt3sas_dev_attrs,
.track_queue_depth = 1,
- .cmd_size = sizeof(struct scsiio_tracker),
};
/* raid transport support for SAS 2.0 HBA devices */
@@ -10214,7 +10211,6 @@ static void pcie_device_make_active(struct MPT3SAS_ADAPTER *ioc,
.shost_attrs = mpt3sas_host_attrs,
.sdev_attrs = mpt3sas_dev_attrs,
.track_queue_depth = 1,
- .cmd_size = sizeof(struct scsiio_tracker),
};
/* raid transport support for SAS 3.0 HBA devices */
diff --git a/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c b/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
index cc07ba4..2a05bf3 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
@@ -259,7 +259,7 @@
sector_t v_lba, p_lba, stripe_off, column, io_size;
u32 stripe_sz, stripe_exp;
u8 num_pds, cmd = scmd->cmnd[0];
- struct scsiio_tracker *st = scsi_cmd_priv(scmd);
+ struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
if (cmd != READ_10 && cmd != WRITE_10 &&
cmd != READ_16 && cmd != WRITE_16)
--
1.8.3.1
^ permalink raw reply related [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
[not found] ` <20190222152433.CF1822086A@mail.kernel.org>
@ 2019-02-25 5:12 ` Sreekanth Reddy
0 siblings, 0 replies; 13+ messages in thread
From: Sreekanth Reddy @ 2019-02-25 5:12 UTC (permalink / raw)
To: Sasha Levin; +Cc: linux-scsi, Sathya Prakash, Suganath Prabu Subramani, stable
On Fri, Feb 22, 2019 at 8:54 PM Sasha Levin <sashal@kernel.org> wrote:
>
> Hi,
>
> [This is an automated email]
>
> This commit has been processed because it contains a -stable tag.
> The stable tag indicates that it's relevant for the following trees: all
>
> The bot has tested the following trees: v4.20.11, v4.19.24, v4.14.102, v4.9.159, v4.4.175, v3.18.135.
>
> v4.19.24: Failed to apply! Possible dependencies:
> 919d8a3f3fef ("scsi: mpt3sas: Convert uses of pr_<level> with MPT3SAS_FMT to ioc_<level>")
>
> v4.14.102: Failed to apply! Possible dependencies:
> 016d5c35e278 ("scsi: mpt3sas: SGL to PRP Translation for I/Os to NVMe devices")
> 02a386df3678 ("scsi: mpt3sas: open-code _scsih_scsi_lookup_get()")
> 05303dfb7380 ("scsi: mpt3sas: use list_splice_init()")
> 12e7c6782bc5 ("scsi: mpt3sas: Introduce mpt3sas_get_st_from_smid()")
> 182ac784b41f ("scsi: mpt3sas: Introduce Base function for cloning.")
> 22ae5a3c2599 ("scsi: mpt3sas: Introduce API to get BAR0 mapped buffer address")
> 494f401bcd07 ("scsi: mpt3sas: Fix sparse warnings")
> 6a2d4618aef3 ("scsi: mpt3sas: separate out _base_recovery_check()")
> 6da999fe5a92 ("scsi: mpt3sas: simplify mpt3sas_scsi_issue_tm()")
> 74fcfa5371b7 ("scsi: mpt3sas: simplify task management functions")
> 93204b782a88 ("scsi: mpt3sas: Lockless access for chain buffers.")
> 9961c9bbf2b4 ("scsi: mpt3sas: check command status before attempting abort")
> aff39e61218f ("scsi: mpt3sas: Added support for nvme encapsulated request message.")
> b0cd285eb57c ("scsi: mpt3sas: always use first reserved smid for ioctl passthrough")
> ba4494d47bd0 ("scsi: mpt3sas: set default value for cb_idx")
> c102e00cf4b8 ("scsi: mpt3sas: API 's to support NVMe drive addition to SML")
> cd5897eda27d ("scsi: mpt3sas: Fix nvme drives checking for tlr.")
> d8335ae2b453 ("scsi: mpt3sas: fix dma_addr_t casts")
> d88e1eaba6ee ("scsi: mpt3sas: Add nvme device support in slave alloc, target alloc and probe")
> dbec4c9040ed ("scsi: mpt3sas: lockless command submission")
>
> v4.9.159: Failed to apply! Possible dependencies:
> 016d5c35e278 ("scsi: mpt3sas: SGL to PRP Translation for I/Os to NVMe devices")
> 12e7c6782bc5 ("scsi: mpt3sas: Introduce mpt3sas_get_st_from_smid()")
> 307d9075a02b ("scsi: mpt3sas: Recognize and act on iopriority info")
> 494f401bcd07 ("scsi: mpt3sas: Fix sparse warnings")
> 81c16f83231a ("scsi: mpt3sas: Use the new MPI 2.6 32-bit Atomic Request Descriptors for SAS35 devices.")
> 998f26aedf41 ("scsi: mpt3sas: Added Device ID's for SAS35 devices and updated MPI header.")
> aff39e61218f ("scsi: mpt3sas: Added support for nvme encapsulated request message.")
> b0cd285eb57c ("scsi: mpt3sas: always use first reserved smid for ioctl passthrough")
> ba4494d47bd0 ("scsi: mpt3sas: set default value for cb_idx")
> c696f7b83ede ("scsi: mpt3sas: Implement device_remove_in_progress check in IOCTL path")
> d8335ae2b453 ("scsi: mpt3sas: fix dma_addr_t casts")
> dbec4c9040ed ("scsi: mpt3sas: lockless command submission")
>
> v4.4.175: Failed to apply! Possible dependencies:
> 016d5c35e278 ("scsi: mpt3sas: SGL to PRP Translation for I/Os to NVMe devices")
> 12e7c6782bc5 ("scsi: mpt3sas: Introduce mpt3sas_get_st_from_smid()")
> 30158dc9bbc9 ("mpt3sas: Never block the Enclosure device")
> 307d9075a02b ("scsi: mpt3sas: Recognize and act on iopriority info")
> 5f0dfb7a9bcc ("mpt3sas: Used "synchronize_irq()"API to synchronize timed-out IO & TMs")
> 6c197093847e ("mpt3sas: Set maximum transfer length per IO to 4MB for VDs")
> 81c16f83231a ("scsi: mpt3sas: Use the new MPI 2.6 32-bit Atomic Request Descriptors for SAS35 devices.")
> 8bbb1cf63f5e ("mpt3sas: Fix warnings exposed by W=1")
> 998f26aedf41 ("scsi: mpt3sas: Added Device ID's for SAS35 devices and updated MPI header.")
> aff39e61218f ("scsi: mpt3sas: Added support for nvme encapsulated request message.")
> b0cd285eb57c ("scsi: mpt3sas: always use first reserved smid for ioctl passthrough")
> b130b0d56fa9 ("mpt3sas: Added support for high port count HBA variants.")
> ba4494d47bd0 ("scsi: mpt3sas: set default value for cb_idx")
> c696f7b83ede ("scsi: mpt3sas: Implement device_remove_in_progress check in IOCTL path")
> d8335ae2b453 ("scsi: mpt3sas: fix dma_addr_t casts")
> dbec4c9040ed ("scsi: mpt3sas: lockless command submission")
> fd0331b32826 ("mpt3sas: Make use of additional HighPriority credit message frames for sending SCSI IO's")
>
> v3.18.135: Failed to apply! Possible dependencies:
> 03d1fb3a6578 ("mpt3sas: Fix for Asynchronous completion of timedout IO and task abort of timedout IO.")
> 12e7c6782bc5 ("scsi: mpt3sas: Introduce mpt3sas_get_st_from_smid()")
> 2b89669ae4ad ("mpt3sas: Bump mpt3sas driver version to v6.100.00.00")
> 2e26c3853206 ("mpt3sas: Update MPI2 strings to MPI2.5")
> 2ecb204d07ac ("scsi: always assign block layer tags if enabled")
> 3c5866565f37 ("mpt2sas: Use mpi headers from mpt3sas")
> 7497392a1193 ("mpt3sas: Move Gen3 HBA's device registration to a separate file")
> 7786ab6aff9c ("mpt3sas: Ported WarpDrive product SSS6200 support")
> 78f97c8f612d ("mpt2sas: Move Gen2 HBA's device registration to a separate file")
> 8a7e4c24e08f ("mpt3sas: Added mpt2sas driver definitions")
> 8f88dc41927f ("mptfusion: don't change queue type in ->change_queue_depth")
> a03bd153b1b3 ("mpt2sas, mpt3sas: Update attribution language to Avago")
> a62182f338b3 ("scsi: provide a generic change_queue_type method")
> ad666a0f41d9 ("mpt2sas, mpt3sas: fix upper bound for the module parameter max_sgl_entries")
> c75683ca13d1 ("mpt3sas : Bump mpt3sas driver version to 9.100.00.00")
> c8b09f6fb67d ("scsi: don't set tagging state from scsi_adjust_queue_depth")
> cb16ef384f15 ("mpt2sas: MPI2 Rev AA (2.00.19) specifications")
> cf75d5d6aa91 ("mpt3sas: simplify ->change_queue_depth")
> d357e84d65df ("mpt3sas: Define 'hba_mpi_version_belonged' IOC variable")
> d42432ad6c5c ("mpt2sas: MPI2 Rev BB (2.00.20) specification and 2.00.35 header files")
> db5ed4dfd5dd ("scsi: drop reason argument from ->change_queue_depth")
> dbec4c9040ed ("scsi: mpt3sas: lockless command submission")
> f9d81cfc2315 ("mpt3sas: Bump mpt3sas Driver version to v5.100.00.00")
> fb77bb5376a5 ("mpt3sas: Added Combined Reply Queue feature to extend up-to 96 MSIX vector support")
>
>
> How should we proceed with this patch?
Shall I prepare the patches against all the above stable kernels and
shall I post them individually? if yes then how should I mention that
the particular is for corresponding stable kernel?
Thanks,
Sreekanth
>
> --
> Thanks,
> Sasha
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
2019-02-21 12:11 [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs Sreekanth Reddy
[not found] ` <20190222152433.CF1822086A@mail.kernel.org>
@ 2019-02-25 19:08 ` Hannes Reinecke
2019-02-26 11:48 ` Sreekanth Reddy
1 sibling, 1 reply; 13+ messages in thread
From: Hannes Reinecke @ 2019-02-25 19:08 UTC (permalink / raw)
To: Sreekanth Reddy, linux-scsi
Cc: Sathya.Prakash, suganath-prabu.subramani, stable
On 2/21/19 1:11 PM, Sreekanth Reddy wrote:
> During expander reset handling, the driver invokes kernel function
> scsi_host_find_tag() to obtain outstanding requests associated with
> the scsi host managed by the driver. Kernel’s block layer may return
> stale entry for one or more outstanding requests if blk-mq is enabled.
> This may lead to Kernel panic if the returned value is inaccessible or
> the memory pointed by the returned value is reused.
>
> Reference of upstream discussion -
> https://patchwork.kernel.org/patch/10734933/
>
> So to fix this issue, driver will use scsi lookup table to track
> outstanding IOs at driver level and it avoids using scsi_host_find_tag().
>
> Have done following changes in this patch,
> * Allocated & initialized scsi_lookup table of type
> (struct scsiio_tracker) and of depth host's can_queue at driver load time
> and it will be deallocated at driver unload time.
>
> * Once scmd is received, driver will take scsiio_tracker at entry
> corresponding to scmd's tag value from scsi_lookup table. Then this
> scsiio_tracker entry is initialized with proper smid, scmd, cb_idx etc.
> And this scsiio_tracker entry contents are cleared before driver
> calling scsi_done callback function.
>
> * scmd's host_scribble variable is used to save the corresponding
> scsiio_tracker address, later at any time driver can easily retrieve the
> scmd's corresponding scsiio_tacker using this host_scribble variable.
>
> * Whenever driver wants to get the outstanding IOs at the driver level
> then driver can go through this scsi_lookup table and if it observe
> any entry with non-null scmd then it means that scmd is outstanding
> at the driver level.
>
> v1 change set:
> Updated the patch description.
>
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
> ---
> drivers/scsi/mpt3sas/mpt3sas_base.c | 45 +++++++++++++++++++++++++++++---
> drivers/scsi/mpt3sas/mpt3sas_base.h | 10 +++++++
> drivers/scsi/mpt3sas/mpt3sas_ctl.c | 2 +-
> drivers/scsi/mpt3sas/mpt3sas_scsih.c | 16 +++++-------
> drivers/scsi/mpt3sas/mpt3sas_warpdrive.c | 2 +-
> 5 files changed, 60 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
> index 0a6cb8f..8e3d0d5 100644
> --- a/drivers/scsi/mpt3sas/mpt3sas_base.c
> +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
> @@ -1301,7 +1301,7 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
>
> cmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
> if (cmd)
> - return scsi_cmd_priv(cmd);
> + return mpt3sas_get_st_from_scmd(cmd);
>
> return NULL;
> }
> @@ -1709,7 +1709,7 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
> struct scsi_cmnd *scmd)
> {
> struct chain_tracker *chain_req;
> - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
> + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
> u16 smid = st->smid;
> u8 chain_offset =
> atomic_read(&ioc->chain_lookup[smid - 1].chain_offset);
> @@ -3203,14 +3203,18 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
> mpt3sas_base_get_smid_scsiio(struct MPT3SAS_ADAPTER *ioc, u8 cb_idx,
> struct scsi_cmnd *scmd)
> {
> - struct scsiio_tracker *request = scsi_cmd_priv(scmd);
> + struct scsiio_tracker *request;
> unsigned int tag = scmd->request->tag;
> u16 smid;
>
> + scmd->host_scribble = (unsigned char *)(&ioc->scsi_lookup[tag]);
> + request = mpt3sas_get_st_from_scmd(scmd);
> +
> smid = tag + 1;
> request->cb_idx = cb_idx;
> request->msix_io = _base_get_msix_index(ioc);
> request->smid = smid;
> + request->scmd = scmd;
> INIT_LIST_HEAD(&request->chain_list);
> return smid;
> }
> @@ -3264,6 +3268,7 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> return;
> st->cb_idx = 0xFF;
> st->direct_io = 0;
> + st->scmd = NULL;
> atomic_set(&ioc->chain_lookup[st->smid - 1].chain_offset, 0);
> st->smid = 0;
> }
> @@ -4252,6 +4257,11 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> ioc->config_page, ioc->config_page_dma);
> }
>
> + if (ioc->scsi_lookup) {
> + free_pages((ulong)ioc->scsi_lookup, ioc->scsi_lookup_pages);
> + ioc->scsi_lookup = NULL;
> + }
> +
> kfree(ioc->hpr_lookup);
> kfree(ioc->internal_lookup);
> if (ioc->chain_lookup) {
> @@ -4377,6 +4387,7 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> max_request_credit = min_t(u16, facts->RequestCredit,
> MAX_HBA_QUEUE_DEPTH);
>
> +retry:
> /* Firmware maintains additional facts->HighPriorityCredit number of
> * credits for HiPriprity Request messages, so hba queue depth will be
> * sum of max_request_credit and high priority queue depth.
> @@ -4581,9 +4592,29 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> (unsigned long long)ioc->request_dma));
> total_sz += sz;
>
> + sz = ioc->shost->can_queue * sizeof(struct scsiio_tracker);
> + ioc->scsi_lookup_pages = get_order(sz);
> + ioc->scsi_lookup = (struct scsiio_tracker *)__get_free_pages(
> + GFP_KERNEL, ioc->scsi_lookup_pages);
> + if (!ioc->scsi_lookup) {
> + /* Retry allocating memory by reducing the queue depth */
> + if ((max_request_credit - 64) >
> + (ioc->internal_depth + INTERNAL_SCSIIO_CMDS_COUNT)) {
> + max_request_credit -= 64;
> + _base_release_memory_pools(ioc);
> + goto retry;
> + } else {
> + ioc_err(ioc,
> + "scsi_lookup: get_free_pages failed, sz(%d)\n",
> + (int)sz);
> + goto out;
> + }
> + }
> +
> dinitprintk(ioc,
> ioc_info(ioc, "scsiio(0x%p): depth(%d)\n",
> ioc->request, ioc->scsiio_depth));
> + total_sz += sz;
>
> ioc->chain_depth = min_t(u32, ioc->chain_depth, MAX_CHAIN_DEPTH);
> sz = ioc->scsiio_depth * sizeof(struct chain_lookup);
> @@ -6239,6 +6270,14 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
>
> spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
>
> + smid = 1;
> + for (i = 0; i < ioc->shost->can_queue; i++, smid++) {
> + ioc->scsi_lookup[i].cb_idx = 0xFF;
> + ioc->scsi_lookup[i].smid = smid;
> + ioc->scsi_lookup[i].scmd = NULL;
> + ioc->scsi_lookup[i].direct_io = 0;
> + }
> +
> /* hi-priority queue */
> INIT_LIST_HEAD(&ioc->hpr_free_list);
> smid = ioc->hi_priority_smid;
> diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h
> index 19158cb..f8c82f6 100644
> --- a/drivers/scsi/mpt3sas/mpt3sas_base.h
> +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h
> @@ -816,6 +816,7 @@ struct chain_lookup {
> /**
> * struct scsiio_tracker - scsi mf request tracker
> * @smid: system message id
> + * @scmd: scsi request pointer
> * @cb_idx: callback index
> * @direct_io: To indicate whether I/O is direct (WARPDRIVE)
> * @chain_list: list of associated firmware chain tracker
> @@ -823,6 +824,7 @@ struct chain_lookup {
> */
> struct scsiio_tracker {
> u16 smid;
> + struct scsi_cmnd *scmd;
> u8 cb_idx;
> u8 direct_io;
> struct pcie_sg_list pcie_sg_list;
> @@ -830,6 +832,12 @@ struct scsiio_tracker {
> u16 msix_io;
> };
>
> +static inline struct scsiio_tracker *
> +mpt3sas_get_st_from_scmd(struct scsi_cmnd *scmd)
> +{
> + return (struct scsiio_tracker *)scmd->host_scribble;
> +}
> +
> /**
> * struct request_tracker - firmware request tracker
> * @smid: system message id
> @@ -1296,6 +1304,8 @@ struct MPT3SAS_ADAPTER {
> u8 *request;
> dma_addr_t request_dma;
> u32 request_dma_sz;
> + struct scsiio_tracker *scsi_lookup;
> + ulong scsi_lookup_pages;
> struct pcie_sg_list *pcie_sg_lookup;
> spinlock_t scsi_lookup_lock;
> int pending_io_count;
> diff --git a/drivers/scsi/mpt3sas/mpt3sas_ctl.c b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> index b2bb47c..ad43e60 100644
> --- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> +++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> @@ -595,7 +595,7 @@ void mpt3sas_ctl_reset_done_handler(struct MPT3SAS_ADAPTER *ioc)
> continue;
> if (priv_data->sas_target->handle != handle)
> continue;
> - st = scsi_cmd_priv(scmd);
> + st = mpt3sas_get_st_from_scmd(scmd);
> tm_request->TaskMID = cpu_to_le16(st->smid);
> found = 1;
> }
> diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
> index 8bb5b8f..86d0e3c 100644
> --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
> +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
> @@ -1465,11 +1465,9 @@ struct scsi_cmnd *
>
> if (smid > 0 &&
> smid <= ioc->scsiio_depth - INTERNAL_SCSIIO_CMDS_COUNT) {
> - u32 unique_tag = smid - 1;
> -
> - scmd = scsi_host_find_tag(ioc->shost, unique_tag);
> + scmd = ioc->scsi_lookup[smid - 1].scmd;
> if (scmd) {
> - st = scsi_cmd_priv(scmd);
> + st = mpt3sas_get_st_from_scmd(scmd);
> if (st->cb_idx == 0xFF || st->smid == 0)
> scmd = NULL;
> }
> @@ -2819,7 +2817,7 @@ int mpt3sas_scsih_issue_locked_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle,
> {
> struct MPT3SAS_ADAPTER *ioc = shost_priv(scmd->device->host);
> struct MPT3SAS_DEVICE *sas_device_priv_data;
> - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
> + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
> u16 handle;
> int r;
>
> @@ -4466,7 +4464,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
> continue;
> count++;
> _scsih_set_satl_pending(scmd, false);
> - st = scsi_cmd_priv(scmd);
> + st = mpt3sas_get_st_from_scmd(scmd);
> mpt3sas_base_clear_st(ioc, st);
> scsi_dma_unmap(scmd);
> if (ioc->pci_error_recovery || ioc->remove_host)
> @@ -5193,7 +5191,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
> * WARPDRIVE: If direct_io is set then it is directIO,
> * the failed direct I/O should be redirected to volume
> */
> - st = scsi_cmd_priv(scmd);
> + st = mpt3sas_get_st_from_scmd(scmd);
> if (st->direct_io &&
> ((ioc_status & MPI2_IOCSTATUS_MASK)
> != MPI2_IOCSTATUS_SCSI_TASK_TERMINATED)) {
> @@ -7335,7 +7333,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
> scmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
> if (!scmd)
> continue;
> - st = scsi_cmd_priv(scmd);
> + st = mpt3sas_get_st_from_scmd(scmd);
> sdev = scmd->device;
> sas_device_priv_data = sdev->hostdata;
> if (!sas_device_priv_data || !sas_device_priv_data->sas_target)
> @@ -10176,7 +10174,6 @@ static void pcie_device_make_active(struct MPT3SAS_ADAPTER *ioc,
> .shost_attrs = mpt3sas_host_attrs,
> .sdev_attrs = mpt3sas_dev_attrs,
> .track_queue_depth = 1,
> - .cmd_size = sizeof(struct scsiio_tracker),
> };
>
> /* raid transport support for SAS 2.0 HBA devices */
> @@ -10214,7 +10211,6 @@ static void pcie_device_make_active(struct MPT3SAS_ADAPTER *ioc,
> .shost_attrs = mpt3sas_host_attrs,
> .sdev_attrs = mpt3sas_dev_attrs,
> .track_queue_depth = 1,
> - .cmd_size = sizeof(struct scsiio_tracker),
> };
>
> /* raid transport support for SAS 3.0 HBA devices */
> diff --git a/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c b/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
> index cc07ba4..2a05bf3 100644
> --- a/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
> +++ b/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
> @@ -259,7 +259,7 @@
> sector_t v_lba, p_lba, stripe_off, column, io_size;
> u32 stripe_sz, stripe_exp;
> u8 num_pds, cmd = scmd->cmnd[0];
> - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
> + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
>
> if (cmd != READ_10 && cmd != WRITE_10 &&
> cmd != READ_16 && cmd != WRITE_16)
>
I still think this is the wrong way of approaching it.
I'd rather using blk_mq_tagset_busy_iter() here; that would avoid the
issue mentioned.
Let's see if I can come up with a patch.
Cheers,
Hannes
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
2019-02-25 19:08 ` Hannes Reinecke
@ 2019-02-26 11:48 ` Sreekanth Reddy
2019-02-26 12:28 ` Hannes Reinecke
0 siblings, 1 reply; 13+ messages in thread
From: Sreekanth Reddy @ 2019-02-26 11:48 UTC (permalink / raw)
To: Hannes Reinecke
Cc: linux-scsi, Sathya Prakash, Suganath Prabu Subramani, stable
On Tue, Feb 26, 2019 at 12:38 AM Hannes Reinecke <hare@suse.de> wrote:
>
> On 2/21/19 1:11 PM, Sreekanth Reddy wrote:
> > During expander reset handling, the driver invokes kernel function
> > scsi_host_find_tag() to obtain outstanding requests associated with
> > the scsi host managed by the driver. Kernel’s block layer may return
> > stale entry for one or more outstanding requests if blk-mq is enabled.
> > This may lead to Kernel panic if the returned value is inaccessible or
> > the memory pointed by the returned value is reused.
> >
> > Reference of upstream discussion -
> > https://patchwork.kernel.org/patch/10734933/
> >
> > So to fix this issue, driver will use scsi lookup table to track
> > outstanding IOs at driver level and it avoids using scsi_host_find_tag().
> >
> > Have done following changes in this patch,
> > * Allocated & initialized scsi_lookup table of type
> > (struct scsiio_tracker) and of depth host's can_queue at driver load time
> > and it will be deallocated at driver unload time.
> >
> > * Once scmd is received, driver will take scsiio_tracker at entry
> > corresponding to scmd's tag value from scsi_lookup table. Then this
> > scsiio_tracker entry is initialized with proper smid, scmd, cb_idx etc.
> > And this scsiio_tracker entry contents are cleared before driver
> > calling scsi_done callback function.
> >
> > * scmd's host_scribble variable is used to save the corresponding
> > scsiio_tracker address, later at any time driver can easily retrieve the
> > scmd's corresponding scsiio_tacker using this host_scribble variable.
> >
> > * Whenever driver wants to get the outstanding IOs at the driver level
> > then driver can go through this scsi_lookup table and if it observe
> > any entry with non-null scmd then it means that scmd is outstanding
> > at the driver level.
> >
> > v1 change set:
> > Updated the patch description.
> >
> > Cc: <stable@vger.kernel.org>
> > Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
> > ---
> > drivers/scsi/mpt3sas/mpt3sas_base.c | 45 +++++++++++++++++++++++++++++---
> > drivers/scsi/mpt3sas/mpt3sas_base.h | 10 +++++++
> > drivers/scsi/mpt3sas/mpt3sas_ctl.c | 2 +-
> > drivers/scsi/mpt3sas/mpt3sas_scsih.c | 16 +++++-------
> > drivers/scsi/mpt3sas/mpt3sas_warpdrive.c | 2 +-
> > 5 files changed, 60 insertions(+), 15 deletions(-)
> >
> > diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
> > index 0a6cb8f..8e3d0d5 100644
> > --- a/drivers/scsi/mpt3sas/mpt3sas_base.c
> > +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
> > @@ -1301,7 +1301,7 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
> >
> > cmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
> > if (cmd)
> > - return scsi_cmd_priv(cmd);
> > + return mpt3sas_get_st_from_scmd(cmd);
> >
> > return NULL;
> > }
> > @@ -1709,7 +1709,7 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
> > struct scsi_cmnd *scmd)
> > {
> > struct chain_tracker *chain_req;
> > - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
> > + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
> > u16 smid = st->smid;
> > u8 chain_offset =
> > atomic_read(&ioc->chain_lookup[smid - 1].chain_offset);
> > @@ -3203,14 +3203,18 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
> > mpt3sas_base_get_smid_scsiio(struct MPT3SAS_ADAPTER *ioc, u8 cb_idx,
> > struct scsi_cmnd *scmd)
> > {
> > - struct scsiio_tracker *request = scsi_cmd_priv(scmd);
> > + struct scsiio_tracker *request;
> > unsigned int tag = scmd->request->tag;
> > u16 smid;
> >
> > + scmd->host_scribble = (unsigned char *)(&ioc->scsi_lookup[tag]);
> > + request = mpt3sas_get_st_from_scmd(scmd);
> > +
> > smid = tag + 1;
> > request->cb_idx = cb_idx;
> > request->msix_io = _base_get_msix_index(ioc);
> > request->smid = smid;
> > + request->scmd = scmd;
> > INIT_LIST_HEAD(&request->chain_list);
> > return smid;
> > }
> > @@ -3264,6 +3268,7 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> > return;
> > st->cb_idx = 0xFF;
> > st->direct_io = 0;
> > + st->scmd = NULL;
> > atomic_set(&ioc->chain_lookup[st->smid - 1].chain_offset, 0);
> > st->smid = 0;
> > }
> > @@ -4252,6 +4257,11 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> > ioc->config_page, ioc->config_page_dma);
> > }
> >
> > + if (ioc->scsi_lookup) {
> > + free_pages((ulong)ioc->scsi_lookup, ioc->scsi_lookup_pages);
> > + ioc->scsi_lookup = NULL;
> > + }
> > +
> > kfree(ioc->hpr_lookup);
> > kfree(ioc->internal_lookup);
> > if (ioc->chain_lookup) {
> > @@ -4377,6 +4387,7 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> > max_request_credit = min_t(u16, facts->RequestCredit,
> > MAX_HBA_QUEUE_DEPTH);
> >
> > +retry:
> > /* Firmware maintains additional facts->HighPriorityCredit number of
> > * credits for HiPriprity Request messages, so hba queue depth will be
> > * sum of max_request_credit and high priority queue depth.
> > @@ -4581,9 +4592,29 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> > (unsigned long long)ioc->request_dma));
> > total_sz += sz;
> >
> > + sz = ioc->shost->can_queue * sizeof(struct scsiio_tracker);
> > + ioc->scsi_lookup_pages = get_order(sz);
> > + ioc->scsi_lookup = (struct scsiio_tracker *)__get_free_pages(
> > + GFP_KERNEL, ioc->scsi_lookup_pages);
> > + if (!ioc->scsi_lookup) {
> > + /* Retry allocating memory by reducing the queue depth */
> > + if ((max_request_credit - 64) >
> > + (ioc->internal_depth + INTERNAL_SCSIIO_CMDS_COUNT)) {
> > + max_request_credit -= 64;
> > + _base_release_memory_pools(ioc);
> > + goto retry;
> > + } else {
> > + ioc_err(ioc,
> > + "scsi_lookup: get_free_pages failed, sz(%d)\n",
> > + (int)sz);
> > + goto out;
> > + }
> > + }
> > +
> > dinitprintk(ioc,
> > ioc_info(ioc, "scsiio(0x%p): depth(%d)\n",
> > ioc->request, ioc->scsiio_depth));
> > + total_sz += sz;
> >
> > ioc->chain_depth = min_t(u32, ioc->chain_depth, MAX_CHAIN_DEPTH);
> > sz = ioc->scsiio_depth * sizeof(struct chain_lookup);
> > @@ -6239,6 +6270,14 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> >
> > spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
> >
> > + smid = 1;
> > + for (i = 0; i < ioc->shost->can_queue; i++, smid++) {
> > + ioc->scsi_lookup[i].cb_idx = 0xFF;
> > + ioc->scsi_lookup[i].smid = smid;
> > + ioc->scsi_lookup[i].scmd = NULL;
> > + ioc->scsi_lookup[i].direct_io = 0;
> > + }
> > +
> > /* hi-priority queue */
> > INIT_LIST_HEAD(&ioc->hpr_free_list);
> > smid = ioc->hi_priority_smid;
> > diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h
> > index 19158cb..f8c82f6 100644
> > --- a/drivers/scsi/mpt3sas/mpt3sas_base.h
> > +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h
> > @@ -816,6 +816,7 @@ struct chain_lookup {
> > /**
> > * struct scsiio_tracker - scsi mf request tracker
> > * @smid: system message id
> > + * @scmd: scsi request pointer
> > * @cb_idx: callback index
> > * @direct_io: To indicate whether I/O is direct (WARPDRIVE)
> > * @chain_list: list of associated firmware chain tracker
> > @@ -823,6 +824,7 @@ struct chain_lookup {
> > */
> > struct scsiio_tracker {
> > u16 smid;
> > + struct scsi_cmnd *scmd;
> > u8 cb_idx;
> > u8 direct_io;
> > struct pcie_sg_list pcie_sg_list;
> > @@ -830,6 +832,12 @@ struct scsiio_tracker {
> > u16 msix_io;
> > };
> >
> > +static inline struct scsiio_tracker *
> > +mpt3sas_get_st_from_scmd(struct scsi_cmnd *scmd)
> > +{
> > + return (struct scsiio_tracker *)scmd->host_scribble;
> > +}
> > +
> > /**
> > * struct request_tracker - firmware request tracker
> > * @smid: system message id
> > @@ -1296,6 +1304,8 @@ struct MPT3SAS_ADAPTER {
> > u8 *request;
> > dma_addr_t request_dma;
> > u32 request_dma_sz;
> > + struct scsiio_tracker *scsi_lookup;
> > + ulong scsi_lookup_pages;
> > struct pcie_sg_list *pcie_sg_lookup;
> > spinlock_t scsi_lookup_lock;
> > int pending_io_count;
> > diff --git a/drivers/scsi/mpt3sas/mpt3sas_ctl.c b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> > index b2bb47c..ad43e60 100644
> > --- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> > +++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> > @@ -595,7 +595,7 @@ void mpt3sas_ctl_reset_done_handler(struct MPT3SAS_ADAPTER *ioc)
> > continue;
> > if (priv_data->sas_target->handle != handle)
> > continue;
> > - st = scsi_cmd_priv(scmd);
> > + st = mpt3sas_get_st_from_scmd(scmd);
> > tm_request->TaskMID = cpu_to_le16(st->smid);
> > found = 1;
> > }
> > diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
> > index 8bb5b8f..86d0e3c 100644
> > --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
> > +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
> > @@ -1465,11 +1465,9 @@ struct scsi_cmnd *
> >
> > if (smid > 0 &&
> > smid <= ioc->scsiio_depth - INTERNAL_SCSIIO_CMDS_COUNT) {
> > - u32 unique_tag = smid - 1;
> > -
> > - scmd = scsi_host_find_tag(ioc->shost, unique_tag);
> > + scmd = ioc->scsi_lookup[smid - 1].scmd;
> > if (scmd) {
> > - st = scsi_cmd_priv(scmd);
> > + st = mpt3sas_get_st_from_scmd(scmd);
> > if (st->cb_idx == 0xFF || st->smid == 0)
> > scmd = NULL;
> > }
> > @@ -2819,7 +2817,7 @@ int mpt3sas_scsih_issue_locked_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle,
> > {
> > struct MPT3SAS_ADAPTER *ioc = shost_priv(scmd->device->host);
> > struct MPT3SAS_DEVICE *sas_device_priv_data;
> > - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
> > + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
> > u16 handle;
> > int r;
> >
> > @@ -4466,7 +4464,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
> > continue;
> > count++;
> > _scsih_set_satl_pending(scmd, false);
> > - st = scsi_cmd_priv(scmd);
> > + st = mpt3sas_get_st_from_scmd(scmd);
> > mpt3sas_base_clear_st(ioc, st);
> > scsi_dma_unmap(scmd);
> > if (ioc->pci_error_recovery || ioc->remove_host)
> > @@ -5193,7 +5191,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
> > * WARPDRIVE: If direct_io is set then it is directIO,
> > * the failed direct I/O should be redirected to volume
> > */
> > - st = scsi_cmd_priv(scmd);
> > + st = mpt3sas_get_st_from_scmd(scmd);
> > if (st->direct_io &&
> > ((ioc_status & MPI2_IOCSTATUS_MASK)
> > != MPI2_IOCSTATUS_SCSI_TASK_TERMINATED)) {
> > @@ -7335,7 +7333,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
> > scmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
> > if (!scmd)
> > continue;
> > - st = scsi_cmd_priv(scmd);
> > + st = mpt3sas_get_st_from_scmd(scmd);
> > sdev = scmd->device;
> > sas_device_priv_data = sdev->hostdata;
> > if (!sas_device_priv_data || !sas_device_priv_data->sas_target)
> > @@ -10176,7 +10174,6 @@ static void pcie_device_make_active(struct MPT3SAS_ADAPTER *ioc,
> > .shost_attrs = mpt3sas_host_attrs,
> > .sdev_attrs = mpt3sas_dev_attrs,
> > .track_queue_depth = 1,
> > - .cmd_size = sizeof(struct scsiio_tracker),
> > };
> >
> > /* raid transport support for SAS 2.0 HBA devices */
> > @@ -10214,7 +10211,6 @@ static void pcie_device_make_active(struct MPT3SAS_ADAPTER *ioc,
> > .shost_attrs = mpt3sas_host_attrs,
> > .sdev_attrs = mpt3sas_dev_attrs,
> > .track_queue_depth = 1,
> > - .cmd_size = sizeof(struct scsiio_tracker),
> > };
> >
> > /* raid transport support for SAS 3.0 HBA devices */
> > diff --git a/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c b/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
> > index cc07ba4..2a05bf3 100644
> > --- a/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
> > +++ b/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
> > @@ -259,7 +259,7 @@
> > sector_t v_lba, p_lba, stripe_off, column, io_size;
> > u32 stripe_sz, stripe_exp;
> > u8 num_pds, cmd = scmd->cmnd[0];
> > - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
> > + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
> >
> > if (cmd != READ_10 && cmd != WRITE_10 &&
> > cmd != READ_16 && cmd != WRITE_16)
> >
> I still think this is the wrong way of approaching it.
> I'd rather using blk_mq_tagset_busy_iter() here; that would avoid the
> issue mentioned.
>
> Let's see if I can come up with a patch.
Hannes,
This API blk_mq_tagset_busy_iter() is not flexible to accommodate it
into mpt3sas driver code. For example driver can’t exit from this API
in-between if need, i.e. While processing Async Broadcast primitive
event if host reset occurs then driver has to wait for this
blk_mq_tagset_busy_iter() API to call the callback function for all
the outstanding requests and no way to quit in-between.
Thanks,
Sreekanth
>
> Cheers,
>
> Hannes
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
2019-02-26 11:48 ` Sreekanth Reddy
@ 2019-02-26 12:28 ` Hannes Reinecke
2019-02-26 13:12 ` Sreekanth Reddy
0 siblings, 1 reply; 13+ messages in thread
From: Hannes Reinecke @ 2019-02-26 12:28 UTC (permalink / raw)
To: Sreekanth Reddy
Cc: linux-scsi, Sathya Prakash, Suganath Prabu Subramani, stable
On 2/26/19 12:48 PM, Sreekanth Reddy wrote:
> On Tue, Feb 26, 2019 at 12:38 AM Hannes Reinecke <hare@suse.de> wrote:
>>
>> On 2/21/19 1:11 PM, Sreekanth Reddy wrote:
>>> During expander reset handling, the driver invokes kernel function
>>> scsi_host_find_tag() to obtain outstanding requests associated with
>>> the scsi host managed by the driver. Kernel’s block layer may return
>>> stale entry for one or more outstanding requests if blk-mq is enabled.
>>> This may lead to Kernel panic if the returned value is inaccessible or
>>> the memory pointed by the returned value is reused.
>>>
>>> Reference of upstream discussion -
>>> https://patchwork.kernel.org/patch/10734933/
>>>
>>> So to fix this issue, driver will use scsi lookup table to track
>>> outstanding IOs at driver level and it avoids using scsi_host_find_tag().
>>>
>>> Have done following changes in this patch,
>>> * Allocated & initialized scsi_lookup table of type
>>> (struct scsiio_tracker) and of depth host's can_queue at driver load time
>>> and it will be deallocated at driver unload time.
>>>
>>> * Once scmd is received, driver will take scsiio_tracker at entry
>>> corresponding to scmd's tag value from scsi_lookup table. Then this
>>> scsiio_tracker entry is initialized with proper smid, scmd, cb_idx etc.
>>> And this scsiio_tracker entry contents are cleared before driver
>>> calling scsi_done callback function.
>>>
>>> * scmd's host_scribble variable is used to save the corresponding
>>> scsiio_tracker address, later at any time driver can easily retrieve the
>>> scmd's corresponding scsiio_tacker using this host_scribble variable.
>>>
>>> * Whenever driver wants to get the outstanding IOs at the driver level
>>> then driver can go through this scsi_lookup table and if it observe
>>> any entry with non-null scmd then it means that scmd is outstanding
>>> at the driver level.
>>>
>>> v1 change set:
>>> Updated the patch description.
>>>
>>> Cc: <stable@vger.kernel.org>
>>> Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
>>> ---
>>> drivers/scsi/mpt3sas/mpt3sas_base.c | 45 +++++++++++++++++++++++++++++---
>>> drivers/scsi/mpt3sas/mpt3sas_base.h | 10 +++++++
>>> drivers/scsi/mpt3sas/mpt3sas_ctl.c | 2 +-
>>> drivers/scsi/mpt3sas/mpt3sas_scsih.c | 16 +++++-------
>>> drivers/scsi/mpt3sas/mpt3sas_warpdrive.c | 2 +-
>>> 5 files changed, 60 insertions(+), 15 deletions(-)
>>>
>>> diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
>>> index 0a6cb8f..8e3d0d5 100644
>>> --- a/drivers/scsi/mpt3sas/mpt3sas_base.c
>>> +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
>>> @@ -1301,7 +1301,7 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
>>>
>>> cmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
>>> if (cmd)
>>> - return scsi_cmd_priv(cmd);
>>> + return mpt3sas_get_st_from_scmd(cmd);
>>>
>>> return NULL;
>>> }
>>> @@ -1709,7 +1709,7 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
>>> struct scsi_cmnd *scmd)
>>> {
>>> struct chain_tracker *chain_req;
>>> - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
>>> + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
>>> u16 smid = st->smid;
>>> u8 chain_offset =
>>> atomic_read(&ioc->chain_lookup[smid - 1].chain_offset);
>>> @@ -3203,14 +3203,18 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
>>> mpt3sas_base_get_smid_scsiio(struct MPT3SAS_ADAPTER *ioc, u8 cb_idx,
>>> struct scsi_cmnd *scmd)
>>> {
>>> - struct scsiio_tracker *request = scsi_cmd_priv(scmd);
>>> + struct scsiio_tracker *request;
>>> unsigned int tag = scmd->request->tag;
>>> u16 smid;
>>>
>>> + scmd->host_scribble = (unsigned char *)(&ioc->scsi_lookup[tag]);
>>> + request = mpt3sas_get_st_from_scmd(scmd);
>>> +
>>> smid = tag + 1;
>>> request->cb_idx = cb_idx;
>>> request->msix_io = _base_get_msix_index(ioc);
>>> request->smid = smid;
>>> + request->scmd = scmd;
>>> INIT_LIST_HEAD(&request->chain_list);
>>> return smid;
>>> }
>>> @@ -3264,6 +3268,7 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
>>> return;
>>> st->cb_idx = 0xFF;
>>> st->direct_io = 0;
>>> + st->scmd = NULL;
>>> atomic_set(&ioc->chain_lookup[st->smid - 1].chain_offset, 0);
>>> st->smid = 0;
>>> }
>>> @@ -4252,6 +4257,11 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
>>> ioc->config_page, ioc->config_page_dma);
>>> }
>>>
>>> + if (ioc->scsi_lookup) {
>>> + free_pages((ulong)ioc->scsi_lookup, ioc->scsi_lookup_pages);
>>> + ioc->scsi_lookup = NULL;
>>> + }
>>> +
>>> kfree(ioc->hpr_lookup);
>>> kfree(ioc->internal_lookup);
>>> if (ioc->chain_lookup) {
>>> @@ -4377,6 +4387,7 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
>>> max_request_credit = min_t(u16, facts->RequestCredit,
>>> MAX_HBA_QUEUE_DEPTH);
>>>
>>> +retry:
>>> /* Firmware maintains additional facts->HighPriorityCredit number of
>>> * credits for HiPriprity Request messages, so hba queue depth will be
>>> * sum of max_request_credit and high priority queue depth.
>>> @@ -4581,9 +4592,29 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
>>> (unsigned long long)ioc->request_dma));
>>> total_sz += sz;
>>>
>>> + sz = ioc->shost->can_queue * sizeof(struct scsiio_tracker);
>>> + ioc->scsi_lookup_pages = get_order(sz);
>>> + ioc->scsi_lookup = (struct scsiio_tracker *)__get_free_pages(
>>> + GFP_KERNEL, ioc->scsi_lookup_pages);
>>> + if (!ioc->scsi_lookup) {
>>> + /* Retry allocating memory by reducing the queue depth */
>>> + if ((max_request_credit - 64) >
>>> + (ioc->internal_depth + INTERNAL_SCSIIO_CMDS_COUNT)) {
>>> + max_request_credit -= 64;
>>> + _base_release_memory_pools(ioc);
>>> + goto retry;
>>> + } else {
>>> + ioc_err(ioc,
>>> + "scsi_lookup: get_free_pages failed, sz(%d)\n",
>>> + (int)sz);
>>> + goto out;
>>> + }
>>> + }
>>> +
>>> dinitprintk(ioc,
>>> ioc_info(ioc, "scsiio(0x%p): depth(%d)\n",
>>> ioc->request, ioc->scsiio_depth));
>>> + total_sz += sz;
>>>
>>> ioc->chain_depth = min_t(u32, ioc->chain_depth, MAX_CHAIN_DEPTH);
>>> sz = ioc->scsiio_depth * sizeof(struct chain_lookup);
>>> @@ -6239,6 +6270,14 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
>>>
>>> spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
>>>
>>> + smid = 1;
>>> + for (i = 0; i < ioc->shost->can_queue; i++, smid++) {
>>> + ioc->scsi_lookup[i].cb_idx = 0xFF;
>>> + ioc->scsi_lookup[i].smid = smid;
>>> + ioc->scsi_lookup[i].scmd = NULL;
>>> + ioc->scsi_lookup[i].direct_io = 0;
>>> + }
>>> +
>>> /* hi-priority queue */
>>> INIT_LIST_HEAD(&ioc->hpr_free_list);
>>> smid = ioc->hi_priority_smid;
>>> diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h
>>> index 19158cb..f8c82f6 100644
>>> --- a/drivers/scsi/mpt3sas/mpt3sas_base.h
>>> +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h
>>> @@ -816,6 +816,7 @@ struct chain_lookup {
>>> /**
>>> * struct scsiio_tracker - scsi mf request tracker
>>> * @smid: system message id
>>> + * @scmd: scsi request pointer
>>> * @cb_idx: callback index
>>> * @direct_io: To indicate whether I/O is direct (WARPDRIVE)
>>> * @chain_list: list of associated firmware chain tracker
>>> @@ -823,6 +824,7 @@ struct chain_lookup {
>>> */
>>> struct scsiio_tracker {
>>> u16 smid;
>>> + struct scsi_cmnd *scmd;
>>> u8 cb_idx;
>>> u8 direct_io;
>>> struct pcie_sg_list pcie_sg_list;
>>> @@ -830,6 +832,12 @@ struct scsiio_tracker {
>>> u16 msix_io;
>>> };
>>>
>>> +static inline struct scsiio_tracker *
>>> +mpt3sas_get_st_from_scmd(struct scsi_cmnd *scmd)
>>> +{
>>> + return (struct scsiio_tracker *)scmd->host_scribble;
>>> +}
>>> +
>>> /**
>>> * struct request_tracker - firmware request tracker
>>> * @smid: system message id
>>> @@ -1296,6 +1304,8 @@ struct MPT3SAS_ADAPTER {
>>> u8 *request;
>>> dma_addr_t request_dma;
>>> u32 request_dma_sz;
>>> + struct scsiio_tracker *scsi_lookup;
>>> + ulong scsi_lookup_pages;
>>> struct pcie_sg_list *pcie_sg_lookup;
>>> spinlock_t scsi_lookup_lock;
>>> int pending_io_count;
>>> diff --git a/drivers/scsi/mpt3sas/mpt3sas_ctl.c b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
>>> index b2bb47c..ad43e60 100644
>>> --- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c
>>> +++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
>>> @@ -595,7 +595,7 @@ void mpt3sas_ctl_reset_done_handler(struct MPT3SAS_ADAPTER *ioc)
>>> continue;
>>> if (priv_data->sas_target->handle != handle)
>>> continue;
>>> - st = scsi_cmd_priv(scmd);
>>> + st = mpt3sas_get_st_from_scmd(scmd);
>>> tm_request->TaskMID = cpu_to_le16(st->smid);
>>> found = 1;
>>> }
>>> diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
>>> index 8bb5b8f..86d0e3c 100644
>>> --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
>>> +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
>>> @@ -1465,11 +1465,9 @@ struct scsi_cmnd *
>>>
>>> if (smid > 0 &&
>>> smid <= ioc->scsiio_depth - INTERNAL_SCSIIO_CMDS_COUNT) {
>>> - u32 unique_tag = smid - 1;
>>> -
>>> - scmd = scsi_host_find_tag(ioc->shost, unique_tag);
>>> + scmd = ioc->scsi_lookup[smid - 1].scmd;
>>> if (scmd) {
>>> - st = scsi_cmd_priv(scmd);
>>> + st = mpt3sas_get_st_from_scmd(scmd);
>>> if (st->cb_idx == 0xFF || st->smid == 0)
>>> scmd = NULL;
>>> }
>>> @@ -2819,7 +2817,7 @@ int mpt3sas_scsih_issue_locked_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle,
>>> {
>>> struct MPT3SAS_ADAPTER *ioc = shost_priv(scmd->device->host);
>>> struct MPT3SAS_DEVICE *sas_device_priv_data;
>>> - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
>>> + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
>>> u16 handle;
>>> int r;
>>>
>>> @@ -4466,7 +4464,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
>>> continue;
>>> count++;
>>> _scsih_set_satl_pending(scmd, false);
>>> - st = scsi_cmd_priv(scmd);
>>> + st = mpt3sas_get_st_from_scmd(scmd);
>>> mpt3sas_base_clear_st(ioc, st);
>>> scsi_dma_unmap(scmd);
>>> if (ioc->pci_error_recovery || ioc->remove_host)
>>> @@ -5193,7 +5191,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
>>> * WARPDRIVE: If direct_io is set then it is directIO,
>>> * the failed direct I/O should be redirected to volume
>>> */
>>> - st = scsi_cmd_priv(scmd);
>>> + st = mpt3sas_get_st_from_scmd(scmd);
>>> if (st->direct_io &&
>>> ((ioc_status & MPI2_IOCSTATUS_MASK)
>>> != MPI2_IOCSTATUS_SCSI_TASK_TERMINATED)) {
>>> @@ -7335,7 +7333,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
>>> scmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
>>> if (!scmd)
>>> continue;
>>> - st = scsi_cmd_priv(scmd);
>>> + st = mpt3sas_get_st_from_scmd(scmd);
>>> sdev = scmd->device;
>>> sas_device_priv_data = sdev->hostdata;
>>> if (!sas_device_priv_data || !sas_device_priv_data->sas_target)
>>> @@ -10176,7 +10174,6 @@ static void pcie_device_make_active(struct MPT3SAS_ADAPTER *ioc,
>>> .shost_attrs = mpt3sas_host_attrs,
>>> .sdev_attrs = mpt3sas_dev_attrs,
>>> .track_queue_depth = 1,
>>> - .cmd_size = sizeof(struct scsiio_tracker),
>>> };
>>>
>>> /* raid transport support for SAS 2.0 HBA devices */
>>> @@ -10214,7 +10211,6 @@ static void pcie_device_make_active(struct MPT3SAS_ADAPTER *ioc,
>>> .shost_attrs = mpt3sas_host_attrs,
>>> .sdev_attrs = mpt3sas_dev_attrs,
>>> .track_queue_depth = 1,
>>> - .cmd_size = sizeof(struct scsiio_tracker),
>>> };
>>>
>>> /* raid transport support for SAS 3.0 HBA devices */
>>> diff --git a/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c b/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
>>> index cc07ba4..2a05bf3 100644
>>> --- a/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
>>> +++ b/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
>>> @@ -259,7 +259,7 @@
>>> sector_t v_lba, p_lba, stripe_off, column, io_size;
>>> u32 stripe_sz, stripe_exp;
>>> u8 num_pds, cmd = scmd->cmnd[0];
>>> - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
>>> + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
>>>
>>> if (cmd != READ_10 && cmd != WRITE_10 &&
>>> cmd != READ_16 && cmd != WRITE_16)
>>>
>> I still think this is the wrong way of approaching it.
>> I'd rather using blk_mq_tagset_busy_iter() here; that would avoid the
>> issue mentioned.
>>
>> Let's see if I can come up with a patch.
>
> Hannes,
>
> This API blk_mq_tagset_busy_iter() is not flexible to accommodate it
> into mpt3sas driver code. For example driver can’t exit from this API
> in-between if need, i.e. While processing Async Broadcast primitive
> event if host reset occurs then driver has to wait for this
> blk_mq_tagset_busy_iter() API to call the callback function for all
> the outstanding requests and no way to quit in-between.
>
This is actually not true; the return value from the iter function
determines if the loop should continue.
If the iter function returns false the loop will be terminated.
Cheers,
Hannes
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
2019-02-26 12:28 ` Hannes Reinecke
@ 2019-02-26 13:12 ` Sreekanth Reddy
2019-02-26 13:49 ` Hannes Reinecke
0 siblings, 1 reply; 13+ messages in thread
From: Sreekanth Reddy @ 2019-02-26 13:12 UTC (permalink / raw)
To: Hannes Reinecke
Cc: linux-scsi, Sathya Prakash, Suganath Prabu Subramani, stable
On Tue, Feb 26, 2019 at 5:59 PM Hannes Reinecke <hare@suse.de> wrote:
>
> On 2/26/19 12:48 PM, Sreekanth Reddy wrote:
> > On Tue, Feb 26, 2019 at 12:38 AM Hannes Reinecke <hare@suse.de> wrote:
> >>
> >> On 2/21/19 1:11 PM, Sreekanth Reddy wrote:
> >>> During expander reset handling, the driver invokes kernel function
> >>> scsi_host_find_tag() to obtain outstanding requests associated with
> >>> the scsi host managed by the driver. Kernel’s block layer may return
> >>> stale entry for one or more outstanding requests if blk-mq is enabled.
> >>> This may lead to Kernel panic if the returned value is inaccessible or
> >>> the memory pointed by the returned value is reused.
> >>>
> >>> Reference of upstream discussion -
> >>> https://patchwork.kernel.org/patch/10734933/
> >>>
> >>> So to fix this issue, driver will use scsi lookup table to track
> >>> outstanding IOs at driver level and it avoids using scsi_host_find_tag().
> >>>
> >>> Have done following changes in this patch,
> >>> * Allocated & initialized scsi_lookup table of type
> >>> (struct scsiio_tracker) and of depth host's can_queue at driver load time
> >>> and it will be deallocated at driver unload time.
> >>>
> >>> * Once scmd is received, driver will take scsiio_tracker at entry
> >>> corresponding to scmd's tag value from scsi_lookup table. Then this
> >>> scsiio_tracker entry is initialized with proper smid, scmd, cb_idx etc.
> >>> And this scsiio_tracker entry contents are cleared before driver
> >>> calling scsi_done callback function.
> >>>
> >>> * scmd's host_scribble variable is used to save the corresponding
> >>> scsiio_tracker address, later at any time driver can easily retrieve the
> >>> scmd's corresponding scsiio_tacker using this host_scribble variable.
> >>>
> >>> * Whenever driver wants to get the outstanding IOs at the driver level
> >>> then driver can go through this scsi_lookup table and if it observe
> >>> any entry with non-null scmd then it means that scmd is outstanding
> >>> at the driver level.
> >>>
> >>> v1 change set:
> >>> Updated the patch description.
> >>>
> >>> Cc: <stable@vger.kernel.org>
> >>> Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
> >>> ---
> >>> drivers/scsi/mpt3sas/mpt3sas_base.c | 45 +++++++++++++++++++++++++++++---
> >>> drivers/scsi/mpt3sas/mpt3sas_base.h | 10 +++++++
> >>> drivers/scsi/mpt3sas/mpt3sas_ctl.c | 2 +-
> >>> drivers/scsi/mpt3sas/mpt3sas_scsih.c | 16 +++++-------
> >>> drivers/scsi/mpt3sas/mpt3sas_warpdrive.c | 2 +-
> >>> 5 files changed, 60 insertions(+), 15 deletions(-)
> >>>
> >>> diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
> >>> index 0a6cb8f..8e3d0d5 100644
> >>> --- a/drivers/scsi/mpt3sas/mpt3sas_base.c
> >>> +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
> >>> @@ -1301,7 +1301,7 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
> >>>
> >>> cmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
> >>> if (cmd)
> >>> - return scsi_cmd_priv(cmd);
> >>> + return mpt3sas_get_st_from_scmd(cmd);
> >>>
> >>> return NULL;
> >>> }
> >>> @@ -1709,7 +1709,7 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
> >>> struct scsi_cmnd *scmd)
> >>> {
> >>> struct chain_tracker *chain_req;
> >>> - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
> >>> + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
> >>> u16 smid = st->smid;
> >>> u8 chain_offset =
> >>> atomic_read(&ioc->chain_lookup[smid - 1].chain_offset);
> >>> @@ -3203,14 +3203,18 @@ static int mpt3sas_remove_dead_ioc_func(void *arg)
> >>> mpt3sas_base_get_smid_scsiio(struct MPT3SAS_ADAPTER *ioc, u8 cb_idx,
> >>> struct scsi_cmnd *scmd)
> >>> {
> >>> - struct scsiio_tracker *request = scsi_cmd_priv(scmd);
> >>> + struct scsiio_tracker *request;
> >>> unsigned int tag = scmd->request->tag;
> >>> u16 smid;
> >>>
> >>> + scmd->host_scribble = (unsigned char *)(&ioc->scsi_lookup[tag]);
> >>> + request = mpt3sas_get_st_from_scmd(scmd);
> >>> +
> >>> smid = tag + 1;
> >>> request->cb_idx = cb_idx;
> >>> request->msix_io = _base_get_msix_index(ioc);
> >>> request->smid = smid;
> >>> + request->scmd = scmd;
> >>> INIT_LIST_HEAD(&request->chain_list);
> >>> return smid;
> >>> }
> >>> @@ -3264,6 +3268,7 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> >>> return;
> >>> st->cb_idx = 0xFF;
> >>> st->direct_io = 0;
> >>> + st->scmd = NULL;
> >>> atomic_set(&ioc->chain_lookup[st->smid - 1].chain_offset, 0);
> >>> st->smid = 0;
> >>> }
> >>> @@ -4252,6 +4257,11 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> >>> ioc->config_page, ioc->config_page_dma);
> >>> }
> >>>
> >>> + if (ioc->scsi_lookup) {
> >>> + free_pages((ulong)ioc->scsi_lookup, ioc->scsi_lookup_pages);
> >>> + ioc->scsi_lookup = NULL;
> >>> + }
> >>> +
> >>> kfree(ioc->hpr_lookup);
> >>> kfree(ioc->internal_lookup);
> >>> if (ioc->chain_lookup) {
> >>> @@ -4377,6 +4387,7 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> >>> max_request_credit = min_t(u16, facts->RequestCredit,
> >>> MAX_HBA_QUEUE_DEPTH);
> >>>
> >>> +retry:
> >>> /* Firmware maintains additional facts->HighPriorityCredit number of
> >>> * credits for HiPriprity Request messages, so hba queue depth will be
> >>> * sum of max_request_credit and high priority queue depth.
> >>> @@ -4581,9 +4592,29 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> >>> (unsigned long long)ioc->request_dma));
> >>> total_sz += sz;
> >>>
> >>> + sz = ioc->shost->can_queue * sizeof(struct scsiio_tracker);
> >>> + ioc->scsi_lookup_pages = get_order(sz);
> >>> + ioc->scsi_lookup = (struct scsiio_tracker *)__get_free_pages(
> >>> + GFP_KERNEL, ioc->scsi_lookup_pages);
> >>> + if (!ioc->scsi_lookup) {
> >>> + /* Retry allocating memory by reducing the queue depth */
> >>> + if ((max_request_credit - 64) >
> >>> + (ioc->internal_depth + INTERNAL_SCSIIO_CMDS_COUNT)) {
> >>> + max_request_credit -= 64;
> >>> + _base_release_memory_pools(ioc);
> >>> + goto retry;
> >>> + } else {
> >>> + ioc_err(ioc,
> >>> + "scsi_lookup: get_free_pages failed, sz(%d)\n",
> >>> + (int)sz);
> >>> + goto out;
> >>> + }
> >>> + }
> >>> +
> >>> dinitprintk(ioc,
> >>> ioc_info(ioc, "scsiio(0x%p): depth(%d)\n",
> >>> ioc->request, ioc->scsiio_depth));
> >>> + total_sz += sz;
> >>>
> >>> ioc->chain_depth = min_t(u32, ioc->chain_depth, MAX_CHAIN_DEPTH);
> >>> sz = ioc->scsiio_depth * sizeof(struct chain_lookup);
> >>> @@ -6239,6 +6270,14 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
> >>>
> >>> spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
> >>>
> >>> + smid = 1;
> >>> + for (i = 0; i < ioc->shost->can_queue; i++, smid++) {
> >>> + ioc->scsi_lookup[i].cb_idx = 0xFF;
> >>> + ioc->scsi_lookup[i].smid = smid;
> >>> + ioc->scsi_lookup[i].scmd = NULL;
> >>> + ioc->scsi_lookup[i].direct_io = 0;
> >>> + }
> >>> +
> >>> /* hi-priority queue */
> >>> INIT_LIST_HEAD(&ioc->hpr_free_list);
> >>> smid = ioc->hi_priority_smid;
> >>> diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h
> >>> index 19158cb..f8c82f6 100644
> >>> --- a/drivers/scsi/mpt3sas/mpt3sas_base.h
> >>> +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h
> >>> @@ -816,6 +816,7 @@ struct chain_lookup {
> >>> /**
> >>> * struct scsiio_tracker - scsi mf request tracker
> >>> * @smid: system message id
> >>> + * @scmd: scsi request pointer
> >>> * @cb_idx: callback index
> >>> * @direct_io: To indicate whether I/O is direct (WARPDRIVE)
> >>> * @chain_list: list of associated firmware chain tracker
> >>> @@ -823,6 +824,7 @@ struct chain_lookup {
> >>> */
> >>> struct scsiio_tracker {
> >>> u16 smid;
> >>> + struct scsi_cmnd *scmd;
> >>> u8 cb_idx;
> >>> u8 direct_io;
> >>> struct pcie_sg_list pcie_sg_list;
> >>> @@ -830,6 +832,12 @@ struct scsiio_tracker {
> >>> u16 msix_io;
> >>> };
> >>>
> >>> +static inline struct scsiio_tracker *
> >>> +mpt3sas_get_st_from_scmd(struct scsi_cmnd *scmd)
> >>> +{
> >>> + return (struct scsiio_tracker *)scmd->host_scribble;
> >>> +}
> >>> +
> >>> /**
> >>> * struct request_tracker - firmware request tracker
> >>> * @smid: system message id
> >>> @@ -1296,6 +1304,8 @@ struct MPT3SAS_ADAPTER {
> >>> u8 *request;
> >>> dma_addr_t request_dma;
> >>> u32 request_dma_sz;
> >>> + struct scsiio_tracker *scsi_lookup;
> >>> + ulong scsi_lookup_pages;
> >>> struct pcie_sg_list *pcie_sg_lookup;
> >>> spinlock_t scsi_lookup_lock;
> >>> int pending_io_count;
> >>> diff --git a/drivers/scsi/mpt3sas/mpt3sas_ctl.c b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> >>> index b2bb47c..ad43e60 100644
> >>> --- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> >>> +++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> >>> @@ -595,7 +595,7 @@ void mpt3sas_ctl_reset_done_handler(struct MPT3SAS_ADAPTER *ioc)
> >>> continue;
> >>> if (priv_data->sas_target->handle != handle)
> >>> continue;
> >>> - st = scsi_cmd_priv(scmd);
> >>> + st = mpt3sas_get_st_from_scmd(scmd);
> >>> tm_request->TaskMID = cpu_to_le16(st->smid);
> >>> found = 1;
> >>> }
> >>> diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
> >>> index 8bb5b8f..86d0e3c 100644
> >>> --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
> >>> +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
> >>> @@ -1465,11 +1465,9 @@ struct scsi_cmnd *
> >>>
> >>> if (smid > 0 &&
> >>> smid <= ioc->scsiio_depth - INTERNAL_SCSIIO_CMDS_COUNT) {
> >>> - u32 unique_tag = smid - 1;
> >>> -
> >>> - scmd = scsi_host_find_tag(ioc->shost, unique_tag);
> >>> + scmd = ioc->scsi_lookup[smid - 1].scmd;
> >>> if (scmd) {
> >>> - st = scsi_cmd_priv(scmd);
> >>> + st = mpt3sas_get_st_from_scmd(scmd);
> >>> if (st->cb_idx == 0xFF || st->smid == 0)
> >>> scmd = NULL;
> >>> }
> >>> @@ -2819,7 +2817,7 @@ int mpt3sas_scsih_issue_locked_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle,
> >>> {
> >>> struct MPT3SAS_ADAPTER *ioc = shost_priv(scmd->device->host);
> >>> struct MPT3SAS_DEVICE *sas_device_priv_data;
> >>> - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
> >>> + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
> >>> u16 handle;
> >>> int r;
> >>>
> >>> @@ -4466,7 +4464,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
> >>> continue;
> >>> count++;
> >>> _scsih_set_satl_pending(scmd, false);
> >>> - st = scsi_cmd_priv(scmd);
> >>> + st = mpt3sas_get_st_from_scmd(scmd);
> >>> mpt3sas_base_clear_st(ioc, st);
> >>> scsi_dma_unmap(scmd);
> >>> if (ioc->pci_error_recovery || ioc->remove_host)
> >>> @@ -5193,7 +5191,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
> >>> * WARPDRIVE: If direct_io is set then it is directIO,
> >>> * the failed direct I/O should be redirected to volume
> >>> */
> >>> - st = scsi_cmd_priv(scmd);
> >>> + st = mpt3sas_get_st_from_scmd(scmd);
> >>> if (st->direct_io &&
> >>> ((ioc_status & MPI2_IOCSTATUS_MASK)
> >>> != MPI2_IOCSTATUS_SCSI_TASK_TERMINATED)) {
> >>> @@ -7335,7 +7333,7 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
> >>> scmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
> >>> if (!scmd)
> >>> continue;
> >>> - st = scsi_cmd_priv(scmd);
> >>> + st = mpt3sas_get_st_from_scmd(scmd);
> >>> sdev = scmd->device;
> >>> sas_device_priv_data = sdev->hostdata;
> >>> if (!sas_device_priv_data || !sas_device_priv_data->sas_target)
> >>> @@ -10176,7 +10174,6 @@ static void pcie_device_make_active(struct MPT3SAS_ADAPTER *ioc,
> >>> .shost_attrs = mpt3sas_host_attrs,
> >>> .sdev_attrs = mpt3sas_dev_attrs,
> >>> .track_queue_depth = 1,
> >>> - .cmd_size = sizeof(struct scsiio_tracker),
> >>> };
> >>>
> >>> /* raid transport support for SAS 2.0 HBA devices */
> >>> @@ -10214,7 +10211,6 @@ static void pcie_device_make_active(struct MPT3SAS_ADAPTER *ioc,
> >>> .shost_attrs = mpt3sas_host_attrs,
> >>> .sdev_attrs = mpt3sas_dev_attrs,
> >>> .track_queue_depth = 1,
> >>> - .cmd_size = sizeof(struct scsiio_tracker),
> >>> };
> >>>
> >>> /* raid transport support for SAS 3.0 HBA devices */
> >>> diff --git a/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c b/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
> >>> index cc07ba4..2a05bf3 100644
> >>> --- a/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
> >>> +++ b/drivers/scsi/mpt3sas/mpt3sas_warpdrive.c
> >>> @@ -259,7 +259,7 @@
> >>> sector_t v_lba, p_lba, stripe_off, column, io_size;
> >>> u32 stripe_sz, stripe_exp;
> >>> u8 num_pds, cmd = scmd->cmnd[0];
> >>> - struct scsiio_tracker *st = scsi_cmd_priv(scmd);
> >>> + struct scsiio_tracker *st = mpt3sas_get_st_from_scmd(scmd);
> >>>
> >>> if (cmd != READ_10 && cmd != WRITE_10 &&
> >>> cmd != READ_16 && cmd != WRITE_16)
> >>>
> >> I still think this is the wrong way of approaching it.
> >> I'd rather using blk_mq_tagset_busy_iter() here; that would avoid the
> >> issue mentioned.
> >>
> >> Let's see if I can come up with a patch.
> >
> > Hannes,
> >
> > This API blk_mq_tagset_busy_iter() is not flexible to accommodate it
> > into mpt3sas driver code. For example driver can’t exit from this API
> > in-between if need, i.e. While processing Async Broadcast primitive
> > event if host reset occurs then driver has to wait for this
> > blk_mq_tagset_busy_iter() API to call the callback function for all
> > the outstanding requests and no way to quit in-between.
> >
> This is actually not true; the return value from the iter function
> determines if the loop should continue.
> If the iter function returns false the loop will be terminated.
Oh ok I will look it again. Also I think this function can be used
only if MQ is enabled, we can't use it in Non-MQ mode (as same fix
need for stable kernels also).
Driver's scsi lookup table mechanism works both in MQ & Non-MQ mode.
Also currently most of the customers are observing this issue with
latest kernels as MQ is enabled by default and this fix is need very
urgently.
Also in below thread we concluded that first we go with driver's scsi
lookup table mechanism, as this fix is need very urgently and in pipe
line we will work to use this blk_mq_tagset_busy_iter() API.
Here I am copying the Kashyap reply from below thread,
"We will address this issue through <mpt3sas> driver changes in two steps.
1. I can use driver's internal memory and will not rely on request/scsi
command. Tag 0...depth loop is not in main IO path, so what we need is
contention free access of the list. Having driver's internal memory and
array will provide that control.
2. As you suggested best way is to use busy tag iteration. (only for blk-mq
stack)"
https://patchwork.kernel.org/patch/10734933/
Thanks,
Sreekanth
>
> Cheers,
>
> Hannes
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
2019-02-26 13:12 ` Sreekanth Reddy
@ 2019-02-26 13:49 ` Hannes Reinecke
2019-02-26 14:33 ` Christoph Hellwig
0 siblings, 1 reply; 13+ messages in thread
From: Hannes Reinecke @ 2019-02-26 13:49 UTC (permalink / raw)
To: Sreekanth Reddy
Cc: linux-scsi, Sathya Prakash, Suganath Prabu Subramani, stable
[-- Attachment #1: Type: text/plain, Size: 2395 bytes --]
On 2/26/19 2:12 PM, Sreekanth Reddy wrote:
> On Tue, Feb 26, 2019 at 5:59 PM Hannes Reinecke <hare@suse.de> wrote:
>>
>> On 2/26/19 12:48 PM, Sreekanth Reddy wrote:
>>> On Tue, Feb 26, 2019 at 12:38 AM Hannes Reinecke <hare@suse.de> wrote:
[ .. ]
>>>
>>> Hannes,
>>>
>>> This API blk_mq_tagset_busy_iter() is not flexible to accommodate it
>>> into mpt3sas driver code. For example driver can’t exit from this API
>>> in-between if need, i.e. While processing Async Broadcast primitive
>>> event if host reset occurs then driver has to wait for this
>>> blk_mq_tagset_busy_iter() API to call the callback function for all
>>> the outstanding requests and no way to quit in-between.
>>>
>> This is actually not true; the return value from the iter function
>> determines if the loop should continue.
>> If the iter function returns false the loop will be terminated.
>
> Oh ok I will look it again. Also I think this function can be used
> only if MQ is enabled, we can't use it in Non-MQ mode (as same fix
> need for stable kernels also).
> Driver's scsi lookup table mechanism works both in MQ & Non-MQ mode.
>
> Also currently most of the customers are observing this issue with
> latest kernels as MQ is enabled by default and this fix is need very
> urgently.
>
> Also in below thread we concluded that first we go with driver's scsi
> lookup table mechanism, as this fix is need very urgently and in pipe
> line we will work to use this blk_mq_tagset_busy_iter() API.
> Here I am copying the Kashyap reply from below thread,
> "We will address this issue through <mpt3sas> driver changes in two steps.
> 1. I can use driver's internal memory and will not rely on request/scsi
> command. Tag 0...depth loop is not in main IO path, so what we need is
> contention free access of the list. Having driver's internal memory and
> array will provide that control.
> 2. As you suggested best way is to use busy tag iteration. (only for blk-mq
> stack)"
>
> https://patchwork.kernel.org/patch/10734933/
>
Attached is a patch to demonstrate my approach.
I am aware that it'll only be useful for latest upstream where the
legacy I/O path has been dropped completely, so we wouldn't need to
worry about it.
For older releases indeed you would need to with something like your
proposed patch, but for upstream I really would like to switch to
blk_mq_tagset_busy() iter.
Cheers,
Hannes
[-- Attachment #2: 0001-mpt3sas-use-blk_mq_tagset_busy_iter-to-iterate-comma.patch --]
[-- Type: text/x-patch, Size: 10561 bytes --]
From 15accbe5764884f11d0c65cd0d6c1a99513aba9a Mon Sep 17 00:00:00 2001
From: Hannes Reinecke <hare@suse.com>
Date: Mon, 25 Feb 2019 20:57:18 +0100
Subject: [PATCH] mpt3sas: use blk_mq_tagset_busy_iter to iterate commands
Instead of blindly checking all possible commands one should be
using blk_mq_tagset_busy_iter() to traverse all active commands.
Signed-off-by: Hannes Reinecke <hare@suse.com>
---
drivers/scsi/mpt3sas/mpt3sas_scsih.c | 262 +++++++++++++++++------------------
1 file changed, 130 insertions(+), 132 deletions(-)
diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
index 8bb5b8f9f4d2..de165c19b53b 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
@@ -4445,6 +4445,26 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
return 0;
}
+static bool _scsih_flush_running_cmds_iter(struct request *req, void *data, bool reserved)
+{
+ struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
+ struct MPT3SAS_ADAPTER *ioc = shost_priv(scmd->device->host);
+ int count = *(int *)data;
+ struct scsiio_tracker *st;
+
+ count++;
+ _scsih_set_satl_pending(scmd, false);
+ st = scsi_cmd_priv(scmd);
+ mpt3sas_base_clear_st(ioc, st);
+ scsi_dma_unmap(scmd);
+ if (ioc->pci_error_recovery || ioc->remove_host)
+ scmd->result = DID_NO_CONNECT << 16;
+ else
+ scmd->result = DID_RESET << 16;
+ scmd->scsi_done(scmd);
+ return true;
+}
+
/**
* _scsih_flush_running_cmds - completing outstanding commands.
* @ioc: per adapter object
@@ -4455,26 +4475,9 @@ static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending)
static void
_scsih_flush_running_cmds(struct MPT3SAS_ADAPTER *ioc)
{
- struct scsi_cmnd *scmd;
- struct scsiio_tracker *st;
- u16 smid;
int count = 0;
- for (smid = 1; smid <= ioc->scsiio_depth; smid++) {
- scmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
- if (!scmd)
- continue;
- count++;
- _scsih_set_satl_pending(scmd, false);
- st = scsi_cmd_priv(scmd);
- mpt3sas_base_clear_st(ioc, st);
- scsi_dma_unmap(scmd);
- if (ioc->pci_error_recovery || ioc->remove_host)
- scmd->result = DID_NO_CONNECT << 16;
- else
- scmd->result = DID_RESET << 16;
- scmd->scsi_done(scmd);
- }
+ blk_mq_tagset_busy_iter(&ioc->shost->tag_set, _scsih_flush_running_cmds_iter, &count);
dtmprintk(ioc, ioc_info(ioc, "completing %d cmds\n", count));
}
@@ -7280,6 +7283,105 @@ _scsih_sas_enclosure_dev_status_change_event(struct MPT3SAS_ADAPTER *ioc,
}
}
+struct _scsih_query_and_abort_task_iter_data {
+ int query_count;
+ int termination_count;
+};
+
+static bool _scsih_query_and_abort_task_iter(struct request *req, void *data, bool reserved)
+{
+ struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
+ struct scsiio_tracker *st = scsi_cmd_priv(scmd);
+ struct scsi_device *sdev = scmd->device;
+ struct MPT3SAS_ADAPTER *ioc = shost_priv(sdev->host);
+ struct MPT3SAS_DEVICE *sas_device_priv_data = sdev->hostdata;
+ struct _scsih_query_and_abort_task_iter_data *iter_data = data;
+ Mpi2SCSITaskManagementReply_t *mpi_reply = ioc->tm_cmds.reply;
+ u16 ioc_status;
+ unsigned long flags;
+ u16 handle;
+ u32 lun;
+ u8 task_abort_retries;
+ int r;
+
+ if (!sas_device_priv_data || !sas_device_priv_data->sas_target)
+ return true;
+ /* skip hidden raid components */
+ if (sas_device_priv_data->sas_target->flags &
+ MPT_TARGET_FLAGS_RAID_COMPONENT)
+ return true;
+ /* skip volumes */
+ if (sas_device_priv_data->sas_target->flags &
+ MPT_TARGET_FLAGS_VOLUME)
+ return true;
+ /* skip PCIe devices */
+ if (sas_device_priv_data->sas_target->flags &
+ MPT_TARGET_FLAGS_PCIE_DEVICE)
+ return true;
+
+ handle = sas_device_priv_data->sas_target->handle;
+ lun = sas_device_priv_data->lun;
+ iter_data->query_count++;
+
+ if (ioc->shost_recovery)
+ return false;
+
+ r = mpt3sas_scsih_issue_tm(ioc, handle, lun,
+ MPI2_SCSITASKMGMT_TASKTYPE_QUERY_TASK, st->smid,
+ st->msix_io, 30, 0);
+ if (r == FAILED) {
+ sdev_printk(KERN_WARNING, sdev,
+ "mpt3sas_scsih_issue_tm: FAILED when sending "
+ "QUERY_TASK: scmd(%p)\n", scmd);
+ spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
+ return false;
+ }
+ ioc_status = le16_to_cpu(mpi_reply->IOCStatus) & MPI2_IOCSTATUS_MASK;
+ if (ioc_status != MPI2_IOCSTATUS_SUCCESS) {
+ sdev_printk(KERN_WARNING, sdev,
+ "query task: FAILED with IOCSTATUS(0x%04x), scmd(%p)\n",
+ ioc_status, scmd);
+ return false;
+ }
+
+ /* see if IO is still owned by IOC and target */
+ if (mpi_reply->ResponseCode ==
+ MPI2_SCSITASKMGMT_RSP_TM_SUCCEEDED ||
+ mpi_reply->ResponseCode ==
+ MPI2_SCSITASKMGMT_RSP_IO_QUEUED_ON_IOC) {
+ return true;;
+ }
+ task_abort_retries = 0;
+tm_retry:
+ if (task_abort_retries++ == 60) {
+ dewtprintk(ioc, ioc_info(ioc, "%s: ABORT_TASK: giving up\n",
+ __func__));
+ return false;
+ }
+
+ if (ioc->shost_recovery)
+ return false;
+
+ r = mpt3sas_scsih_issue_tm(ioc, handle, sdev->lun,
+ MPI2_SCSITASKMGMT_TASKTYPE_ABORT_TASK, st->smid,
+ st->msix_io, 30, 0);
+ if (r == FAILED || st->cb_idx != 0xFF) {
+ sdev_printk(KERN_WARNING, sdev,
+ "mpt3sas_scsih_issue_tm: ABORT_TASK: FAILED : "
+ "scmd(%p)\n", scmd);
+ goto tm_retry;
+ }
+
+ if (task_abort_retries > 1)
+ sdev_printk(KERN_WARNING, sdev,
+ "mpt3sas_scsih_issue_tm: ABORT_TASK: RETRIES (%d):"
+ " scmd(%p)\n",
+ task_abort_retries - 1, scmd);
+
+ iter_data->termination_count += le32_to_cpu(mpi_reply->TerminationCount);
+ return true;
+}
+
/**
* _scsih_sas_broadcast_primitive_event - handle broadcast events
* @ioc: per adapter object
@@ -7290,23 +7392,14 @@ static void
_scsih_sas_broadcast_primitive_event(struct MPT3SAS_ADAPTER *ioc,
struct fw_event_work *fw_event)
{
- struct scsi_cmnd *scmd;
- struct scsi_device *sdev;
- struct scsiio_tracker *st;
- u16 smid, handle;
- u32 lun;
- struct MPT3SAS_DEVICE *sas_device_priv_data;
- u32 termination_count;
- u32 query_count;
- Mpi2SCSITaskManagementReply_t *mpi_reply;
Mpi2EventDataSasBroadcastPrimitive_t *event_data =
(Mpi2EventDataSasBroadcastPrimitive_t *)
fw_event->event_data;
- u16 ioc_status;
- unsigned long flags;
- int r;
u8 max_retries = 0;
- u8 task_abort_retries;
+ struct _scsih_query_and_abort_task_iter_data iter_data = {
+ .query_count = 0,
+ .termination_count = 0,
+ };
mutex_lock(&ioc->tm_cmds.mutex);
ioc_info(ioc, "%s: enter: phy number(%d), width(%d)\n",
@@ -7314,8 +7407,6 @@ _scsih_sas_broadcast_primitive_event(struct MPT3SAS_ADAPTER *ioc,
_scsih_block_io_all_device(ioc);
- spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
- mpi_reply = ioc->tm_cmds.reply;
broadcast_aen_retry:
/* sanity checks for retrying this loop */
@@ -7327,101 +7418,11 @@ _scsih_sas_broadcast_primitive_event(struct MPT3SAS_ADAPTER *ioc,
ioc_info(ioc, "%s: %d retry\n",
__func__, max_retries - 1));
- termination_count = 0;
- query_count = 0;
- for (smid = 1; smid <= ioc->scsiio_depth; smid++) {
- if (ioc->shost_recovery)
- goto out;
- scmd = mpt3sas_scsih_scsi_lookup_get(ioc, smid);
- if (!scmd)
- continue;
- st = scsi_cmd_priv(scmd);
- sdev = scmd->device;
- sas_device_priv_data = sdev->hostdata;
- if (!sas_device_priv_data || !sas_device_priv_data->sas_target)
- continue;
- /* skip hidden raid components */
- if (sas_device_priv_data->sas_target->flags &
- MPT_TARGET_FLAGS_RAID_COMPONENT)
- continue;
- /* skip volumes */
- if (sas_device_priv_data->sas_target->flags &
- MPT_TARGET_FLAGS_VOLUME)
- continue;
- /* skip PCIe devices */
- if (sas_device_priv_data->sas_target->flags &
- MPT_TARGET_FLAGS_PCIE_DEVICE)
- continue;
-
- handle = sas_device_priv_data->sas_target->handle;
- lun = sas_device_priv_data->lun;
- query_count++;
-
- if (ioc->shost_recovery)
- goto out;
-
- spin_unlock_irqrestore(&ioc->scsi_lookup_lock, flags);
- r = mpt3sas_scsih_issue_tm(ioc, handle, lun,
- MPI2_SCSITASKMGMT_TASKTYPE_QUERY_TASK, st->smid,
- st->msix_io, 30, 0);
- if (r == FAILED) {
- sdev_printk(KERN_WARNING, sdev,
- "mpt3sas_scsih_issue_tm: FAILED when sending "
- "QUERY_TASK: scmd(%p)\n", scmd);
- spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
- goto broadcast_aen_retry;
- }
- ioc_status = le16_to_cpu(mpi_reply->IOCStatus)
- & MPI2_IOCSTATUS_MASK;
- if (ioc_status != MPI2_IOCSTATUS_SUCCESS) {
- sdev_printk(KERN_WARNING, sdev,
- "query task: FAILED with IOCSTATUS(0x%04x), scmd(%p)\n",
- ioc_status, scmd);
- spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
- goto broadcast_aen_retry;
- }
-
- /* see if IO is still owned by IOC and target */
- if (mpi_reply->ResponseCode ==
- MPI2_SCSITASKMGMT_RSP_TM_SUCCEEDED ||
- mpi_reply->ResponseCode ==
- MPI2_SCSITASKMGMT_RSP_IO_QUEUED_ON_IOC) {
- spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
- continue;
- }
- task_abort_retries = 0;
- tm_retry:
- if (task_abort_retries++ == 60) {
- dewtprintk(ioc,
- ioc_info(ioc, "%s: ABORT_TASK: giving up\n",
- __func__));
- spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
- goto broadcast_aen_retry;
- }
-
- if (ioc->shost_recovery)
- goto out_no_lock;
-
- r = mpt3sas_scsih_issue_tm(ioc, handle, sdev->lun,
- MPI2_SCSITASKMGMT_TASKTYPE_ABORT_TASK, st->smid,
- st->msix_io, 30, 0);
- if (r == FAILED || st->cb_idx != 0xFF) {
- sdev_printk(KERN_WARNING, sdev,
- "mpt3sas_scsih_issue_tm: ABORT_TASK: FAILED : "
- "scmd(%p)\n", scmd);
- goto tm_retry;
- }
-
- if (task_abort_retries > 1)
- sdev_printk(KERN_WARNING, sdev,
- "mpt3sas_scsih_issue_tm: ABORT_TASK: RETRIES (%d):"
- " scmd(%p)\n",
- task_abort_retries - 1, scmd);
-
- termination_count += le32_to_cpu(mpi_reply->TerminationCount);
- spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
- }
-
+ if (ioc->shost_recovery)
+ goto out;
+ blk_mq_tagset_busy_iter(&ioc->shost->tag_set, _scsih_query_and_abort_task_iter, &iter_data);
+ if (ioc->shost_recovery)
+ goto out;
if (ioc->broadcast_aen_pending) {
dewtprintk(ioc,
ioc_info(ioc,
@@ -7432,12 +7433,9 @@ _scsih_sas_broadcast_primitive_event(struct MPT3SAS_ADAPTER *ioc,
}
out:
- spin_unlock_irqrestore(&ioc->scsi_lookup_lock, flags);
- out_no_lock:
-
dewtprintk(ioc,
ioc_info(ioc, "%s - exit, query_count = %d termination_count = %d\n",
- __func__, query_count, termination_count));
+ __func__, iter_data.query_count, iter_data.termination_count));
ioc->broadcast_aen_busy = 0;
if (!ioc->shost_recovery)
--
2.16.4
^ permalink raw reply related [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
2019-02-26 13:49 ` Hannes Reinecke
@ 2019-02-26 14:33 ` Christoph Hellwig
2019-02-26 14:40 ` Martin K. Petersen
2019-02-26 14:53 ` Hannes Reinecke
0 siblings, 2 replies; 13+ messages in thread
From: Christoph Hellwig @ 2019-02-26 14:33 UTC (permalink / raw)
To: Hannes Reinecke
Cc: Sreekanth Reddy, linux-scsi, Sathya Prakash,
Suganath Prabu Subramani, stable
On Tue, Feb 26, 2019 at 02:49:30PM +0100, Hannes Reinecke wrote:
> Attached is a patch to demonstrate my approach.
> I am aware that it'll only be useful for latest upstream where the legacy
> I/O path has been dropped completely, so we wouldn't need to worry about it.
> For older releases indeed you would need to with something like your
> proposed patch, but for upstream I really would like to switch to
> blk_mq_tagset_busy() iter.
While this is better than the driver private tracking we really should
not have to iterate all outstanding command, because if we have any
there is a bug we need to fix in the higher layers instead of working
around it in the drivers.
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
2019-02-26 14:33 ` Christoph Hellwig
@ 2019-02-26 14:40 ` Martin K. Petersen
2019-02-26 14:53 ` Hannes Reinecke
1 sibling, 0 replies; 13+ messages in thread
From: Martin K. Petersen @ 2019-02-26 14:40 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Hannes Reinecke, Sreekanth Reddy, linux-scsi, Sathya Prakash,
Suganath Prabu Subramani, stable
> While this is better than the driver private tracking we really should
> not have to iterate all outstanding command, because if we have any
> there is a bug we need to fix in the higher layers instead of working
> around it in the drivers.
I agree completely.
--
Martin K. Petersen Oracle Linux Engineering
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
2019-02-26 14:33 ` Christoph Hellwig
2019-02-26 14:40 ` Martin K. Petersen
@ 2019-02-26 14:53 ` Hannes Reinecke
2019-02-26 16:05 ` Kashyap Desai
1 sibling, 1 reply; 13+ messages in thread
From: Hannes Reinecke @ 2019-02-26 14:53 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Sreekanth Reddy, linux-scsi, Sathya Prakash,
Suganath Prabu Subramani, stable
On 2/26/19 3:33 PM, Christoph Hellwig wrote:
> On Tue, Feb 26, 2019 at 02:49:30PM +0100, Hannes Reinecke wrote:
>> Attached is a patch to demonstrate my approach.
>> I am aware that it'll only be useful for latest upstream where the legacy
>> I/O path has been dropped completely, so we wouldn't need to worry about it.
>> For older releases indeed you would need to with something like your
>> proposed patch, but for upstream I really would like to switch to
>> blk_mq_tagset_busy() iter.
>
> While this is better than the driver private tracking we really should
> not have to iterate all outstanding command, because if we have any
> there is a bug we need to fix in the higher layers instead of working
> around it in the drivers.
>
Ah-ha.
But what else should we be doing here?
The driver needs to abort all outstanding commands; I somewhat fail to
see how we could be doing it otherwise ...
Cheers,
Hannes
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
2019-02-26 14:53 ` Hannes Reinecke
@ 2019-02-26 16:05 ` Kashyap Desai
2019-02-27 14:50 ` Martin K. Petersen
0 siblings, 1 reply; 13+ messages in thread
From: Kashyap Desai @ 2019-02-26 16:05 UTC (permalink / raw)
To: Hannes Reinecke
Cc: Christoph Hellwig, Sreekanth Reddy, linux-scsi, Sathya Prakash,
Suganath Prabu Subramani, stable
On Tue, Feb 26, 2019 at 8:23 PM Hannes Reinecke <hare@suse.de> wrote:
>
> On 2/26/19 3:33 PM, Christoph Hellwig wrote:
> > On Tue, Feb 26, 2019 at 02:49:30PM +0100, Hannes Reinecke wrote:
> >> Attached is a patch to demonstrate my approach.
> >> I am aware that it'll only be useful for latest upstream where the legacy
> >> I/O path has been dropped completely, so we wouldn't need to worry about it.
> >> For older releases indeed you would need to with something like your
> >> proposed patch, but for upstream I really would like to switch to
> >> blk_mq_tagset_busy() iter.
> >
> > While this is better than the driver private tracking we really should
> > not have to iterate all outstanding command, because if we have any
> > there is a bug we need to fix in the higher layers instead of working
> > around it in the drivers.
Hi Chris, Looking at other driver's code, I think similar issue is
impacted to many scsi hbas (like fnic, qla4xxx, snic etc..). They also
need similar logic to traverse outstanding scsi commands.
One of the example is - At the time of HBA reset driver would like to
release scsi command back to SML to retry and for that driver requires
to loop all possible smid to figure out outstanding scsi command
@Firmware/SML level.
> >
> Ah-ha.
>
> But what else should we be doing here?
> The driver needs to abort all outstanding commands; I somewhat fail to
> see how we could be doing it otherwise ...
Hannes, Primary drawback of using "blk_mq_tagset_busy_iter" is API is
only for blk-mq and it is not available for all the kernel with blk-mq
support. We have seen multiple failures from customer and those
kernels does not support blk_mq_tagset_busy_iter. In fact, blk-mq and
non-mq stack is alive in many Linux distribution and customer is using
those. If we just scope to fix current kernel 5.x (which does not have
non-mq support), we can opt blk_mq_tagset_busy_iter(). Earlier I
requested upstream to accept driver changes without
blk_mq_tagset_busy_iter() because it is hitting many customers so we
are looking for generic fix which can server both blk-mq as well as
non-mq.
We will certainly enhance and optimize working this area (driver
trying to find outstanding scsi command) with scsi mailing list as
incremental approach.
Kashyap
>
> Cheers,
>
> Hannes
>
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
2019-02-26 16:05 ` Kashyap Desai
@ 2019-02-27 14:50 ` Martin K. Petersen
2019-02-28 13:25 ` Sreekanth Reddy
0 siblings, 1 reply; 13+ messages in thread
From: Martin K. Petersen @ 2019-02-27 14:50 UTC (permalink / raw)
To: Kashyap Desai
Cc: Hannes Reinecke, Christoph Hellwig, Sreekanth Reddy, linux-scsi,
Sathya Prakash, Suganath Prabu Subramani, stable
Kashyap,
> Primary drawback of using "blk_mq_tagset_busy_iter" is API is only for
> blk-mq and it is not available for all the kernel with blk-mq
> support. We have seen multiple failures from customer and those
> kernels does not support blk_mq_tagset_busy_iter. In fact, blk-mq and
> non-mq stack is alive in many Linux distribution and customer is using
> those.
I'm afraid the burden falls upon Broadcom to manage enablement patches
for older kernels. So the non-MQ/non-tagset-busy-iter cases are not
particularly relevant for the discussion here.
Let's focus on getting some usable plumbing that drivers can use to
abort oustanding tags.
--
Martin K. Petersen Oracle Linux Engineering
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs
2019-02-27 14:50 ` Martin K. Petersen
@ 2019-02-28 13:25 ` Sreekanth Reddy
0 siblings, 0 replies; 13+ messages in thread
From: Sreekanth Reddy @ 2019-02-28 13:25 UTC (permalink / raw)
To: Martin K. Petersen
Cc: Kashyap Desai, Hannes Reinecke, Christoph Hellwig, linux-scsi,
Sathya Prakash, Suganath Prabu Subramani, stable
On Wed, Feb 27, 2019 at 8:20 PM Martin K. Petersen
<martin.petersen@oracle.com> wrote:
>
>
> Kashyap,
>
> > Primary drawback of using "blk_mq_tagset_busy_iter" is API is only for
> > blk-mq and it is not available for all the kernel with blk-mq
> > support. We have seen multiple failures from customer and those
> > kernels does not support blk_mq_tagset_busy_iter. In fact, blk-mq and
> > non-mq stack is alive in many Linux distribution and customer is using
> > those.
>
> I'm afraid the burden falls upon Broadcom to manage enablement patches
> for older kernels. So the non-MQ/non-tagset-busy-iter cases are not
> particularly relevant for the discussion here.
>
> Let's focus on getting some usable plumbing that drivers can use to
> abort oustanding tags.
Today I have discussed with Kashyap internally and found below solution,
Solution:
Instead of calling scsi_host_find_tag() API for each and every smid
from one to shost->can_queue, now driver will call this API only for
those smid's which are outstanding at the driver level. Driver will
determine whether this smid is outstanding at driver level by looking
into it's corresponding MPI request frame, if it's MPI request frame
is empty then it means that this smid is free and no need to call
scsi_host_find_tag() API for this smid. By doing this driver will
invoke scsi_host_find_tag() for only those tags which are outstanding
at the driver level.
Driver will check whether particular MPI request frame is empty or not
by looking into the "DevHandle" field. if this field is zero then it
means that this MPI request is empty. Also driver will memset the MPI
request frame once the corresponding scmd is processed (i.e. just
before calling scmd->done function).
Here is the code change. currently I am testing this code and will
post this patch once the testing completes. Please let us known your
thoughts on this.
diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c
b/drivers/scsi/mpt3sas/mpt3sas_base.c
index e577744..1d8c584 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
@@ -3281,12 +3281,18 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc,
if (smid < ioc->hi_priority_smid) {
struct scsiio_tracker *st;
+ void *request;
st = _get_st_from_smid(ioc, smid);
if (!st) {
_base_recovery_check(ioc);
return;
}
+
+ /* Clear MPI request frame */
+ request = mpt3sas_base_get_msg_frame(ioc, smid);
+ memset(request, 0, ioc->request_sz);
+
mpt3sas_base_clear_st(ioc, st);
_base_recovery_check(ioc);
return;
diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
index 8bb5b8f..55bec88 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
@@ -1462,11 +1462,20 @@ struct scsi_cmnd *
{
struct scsi_cmnd *scmd = NULL;
struct scsiio_tracker *st;
+ Mpi25SCSIIORequest_t *mpi_request;
if (smid > 0 &&
smid <= ioc->scsiio_depth - INTERNAL_SCSIIO_CMDS_COUNT) {
u32 unique_tag = smid - 1;
+ mpi_request = mpt3sas_base_get_msg_frame(ioc, smid);
+
+ /* DevHandle zero means that this smid is free
+ * at driver level, So return NULL.
+ */
+ if (!mpi_request->DevHandle)
+ return scmd;
+
scmd = scsi_host_find_tag(ioc->shost, unique_tag);
if (scmd) {
st = scsi_cmd_priv(scmd);
---
Thanks,
Sreekanth
>
> --
> Martin K. Petersen Oracle Linux Engineering
^ permalink raw reply related [flat|nested] 13+ messages in thread
end of thread, other threads:[~2019-02-28 13:25 UTC | newest]
Thread overview: 13+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-02-21 12:11 [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs Sreekanth Reddy
[not found] ` <20190222152433.CF1822086A@mail.kernel.org>
2019-02-25 5:12 ` Sreekanth Reddy
2019-02-25 19:08 ` Hannes Reinecke
2019-02-26 11:48 ` Sreekanth Reddy
2019-02-26 12:28 ` Hannes Reinecke
2019-02-26 13:12 ` Sreekanth Reddy
2019-02-26 13:49 ` Hannes Reinecke
2019-02-26 14:33 ` Christoph Hellwig
2019-02-26 14:40 ` Martin K. Petersen
2019-02-26 14:53 ` Hannes Reinecke
2019-02-26 16:05 ` Kashyap Desai
2019-02-27 14:50 ` Martin K. Petersen
2019-02-28 13:25 ` Sreekanth Reddy
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