* [PATCH AUTOSEL 5.18 14/53] scsi: ufs: Simplify ufshcd_clear_cmd()
[not found] <20220628021839.594423-1-sashal@kernel.org>
@ 2022-06-28 2:18 ` Sasha Levin
2022-06-28 2:18 ` [PATCH AUTOSEL 5.18 15/53] scsi: ufs: Support clearing multiple commands at once Sasha Levin
2022-06-28 2:18 ` [PATCH AUTOSEL 5.18 16/53] scsi: ufs: Fix a race between the interrupt handler and the reset handler Sasha Levin
2 siblings, 0 replies; 3+ messages in thread
From: Sasha Levin @ 2022-06-28 2:18 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Bart Van Assche, Stanley Chu, Adrian Hunter, Martin K . Petersen,
Sasha Levin, jejb, matthias.bgg, beanhuo, avri.altman,
daejun7.park, linux-scsi, linux-arm-kernel, linux-mediatek
From: Bart Van Assche <bvanassche@acm.org>
[ Upstream commit da8badd7d3583f447eac2ab65a332f2d773deca1 ]
Remove the local variable 'err'. This patch does not change any
functionality.
Link: https://lore.kernel.org/r/20220613214442.212466-2-bvanassche@acm.org
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/ufs/ufshcd.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 4c9eb4be449c..8f26c4c09c66 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2856,7 +2856,6 @@ static int ufshcd_compose_dev_cmd(struct ufs_hba *hba,
static int
ufshcd_clear_cmd(struct ufs_hba *hba, int tag)
{
- int err = 0;
unsigned long flags;
u32 mask = 1 << tag;
@@ -2869,11 +2868,8 @@ ufshcd_clear_cmd(struct ufs_hba *hba, int tag)
* wait for h/w to clear corresponding bit in door-bell.
* max. wait is 1 sec.
*/
- err = ufshcd_wait_for_register(hba,
- REG_UTP_TRANSFER_REQ_DOOR_BELL,
- mask, ~mask, 1000, 1000);
-
- return err;
+ return ufshcd_wait_for_register(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL,
+ mask, ~mask, 1000, 1000);
}
static int
--
2.35.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH AUTOSEL 5.18 15/53] scsi: ufs: Support clearing multiple commands at once
[not found] <20220628021839.594423-1-sashal@kernel.org>
2022-06-28 2:18 ` [PATCH AUTOSEL 5.18 14/53] scsi: ufs: Simplify ufshcd_clear_cmd() Sasha Levin
@ 2022-06-28 2:18 ` Sasha Levin
2022-06-28 2:18 ` [PATCH AUTOSEL 5.18 16/53] scsi: ufs: Fix a race between the interrupt handler and the reset handler Sasha Levin
2 siblings, 0 replies; 3+ messages in thread
From: Sasha Levin @ 2022-06-28 2:18 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Bart Van Assche, Stanley Chu, Adrian Hunter, Martin K . Petersen,
Sasha Levin, jejb, matthias.bgg, beanhuo, avri.altman,
daejun7.park, linux-scsi, linux-arm-kernel, linux-mediatek
From: Bart Van Assche <bvanassche@acm.org>
[ Upstream commit d1a7644648b7cdacaf8d1013a4285001911e9bc8 ]
Modify ufshcd_clear_cmd() such that it supports clearing multiple commands
at once instead of one command at a time. This change will be used in a
later patch to reduce the time spent in the reset handler.
Link: https://lore.kernel.org/r/20220613214442.212466-3-bvanassche@acm.org
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/ufs/ufshcd.c | 42 ++++++++++++++++++++++++++-------------
1 file changed, 28 insertions(+), 14 deletions(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 8f26c4c09c66..f08586a4470c 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -734,17 +734,28 @@ static enum utp_ocs ufshcd_get_tr_ocs(struct ufshcd_lrb *lrbp)
}
/**
- * ufshcd_utrl_clear - Clear a bit in UTRLCLR register
+ * ufshcd_utrl_clear() - Clear requests from the controller request list.
* @hba: per adapter instance
- * @pos: position of the bit to be cleared
+ * @mask: mask with one bit set for each request to be cleared
*/
-static inline void ufshcd_utrl_clear(struct ufs_hba *hba, u32 pos)
+static inline void ufshcd_utrl_clear(struct ufs_hba *hba, u32 mask)
{
if (hba->quirks & UFSHCI_QUIRK_BROKEN_REQ_LIST_CLR)
- ufshcd_writel(hba, (1 << pos), REG_UTP_TRANSFER_REQ_LIST_CLEAR);
- else
- ufshcd_writel(hba, ~(1 << pos),
- REG_UTP_TRANSFER_REQ_LIST_CLEAR);
+ mask = ~mask;
+ /*
+ * From the UFSHCI specification: "UTP Transfer Request List CLear
+ * Register (UTRLCLR): This field is bit significant. Each bit
+ * corresponds to a slot in the UTP Transfer Request List, where bit 0
+ * corresponds to request slot 0. A bit in this field is set to ‘0’
+ * by host software to indicate to the host controller that a transfer
+ * request slot is cleared. The host controller
+ * shall free up any resources associated to the request slot
+ * immediately, and shall set the associated bit in UTRLDBR to ‘0’. The
+ * host software indicates no change to request slots by setting the
+ * associated bits in this field to ‘1’. Bits in this field shall only
+ * be set ‘1’ or ‘0’ by host software when UTRLRSR is set to ‘1’."
+ */
+ ufshcd_writel(hba, ~mask, REG_UTP_TRANSFER_REQ_LIST_CLEAR);
}
/**
@@ -2853,15 +2864,18 @@ static int ufshcd_compose_dev_cmd(struct ufs_hba *hba,
return ufshcd_compose_devman_upiu(hba, lrbp);
}
-static int
-ufshcd_clear_cmd(struct ufs_hba *hba, int tag)
+/*
+ * Clear all the requests from the controller for which a bit has been set in
+ * @mask and wait until the controller confirms that these requests have been
+ * cleared.
+ */
+static int ufshcd_clear_cmds(struct ufs_hba *hba, u32 mask)
{
unsigned long flags;
- u32 mask = 1 << tag;
/* clear outstanding transaction before retry */
spin_lock_irqsave(hba->host->host_lock, flags);
- ufshcd_utrl_clear(hba, tag);
+ ufshcd_utrl_clear(hba, mask);
spin_unlock_irqrestore(hba->host->host_lock, flags);
/*
@@ -2949,7 +2963,7 @@ static int ufshcd_wait_for_dev_cmd(struct ufs_hba *hba,
err = -ETIMEDOUT;
dev_dbg(hba->dev, "%s: dev_cmd request timedout, tag %d\n",
__func__, lrbp->task_tag);
- if (!ufshcd_clear_cmd(hba, lrbp->task_tag))
+ if (!ufshcd_clear_cmds(hba, 1U << lrbp->task_tag))
/* successfully cleared the command, retry if needed */
err = -EAGAIN;
/*
@@ -6984,7 +6998,7 @@ static int ufshcd_eh_device_reset_handler(struct scsi_cmnd *cmd)
/* clear the commands that were pending for corresponding LUN */
for_each_set_bit(pos, &hba->outstanding_reqs, hba->nutrs) {
if (hba->lrb[pos].lun == lun) {
- err = ufshcd_clear_cmd(hba, pos);
+ err = ufshcd_clear_cmds(hba, 1U << pos);
if (err)
break;
__ufshcd_transfer_req_compl(hba, 1U << pos);
@@ -7086,7 +7100,7 @@ static int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag)
goto out;
}
- err = ufshcd_clear_cmd(hba, tag);
+ err = ufshcd_clear_cmds(hba, 1U << tag);
if (err)
dev_err(hba->dev, "%s: Failed clearing cmd at tag %d, err %d\n",
__func__, tag, err);
--
2.35.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH AUTOSEL 5.18 16/53] scsi: ufs: Fix a race between the interrupt handler and the reset handler
[not found] <20220628021839.594423-1-sashal@kernel.org>
2022-06-28 2:18 ` [PATCH AUTOSEL 5.18 14/53] scsi: ufs: Simplify ufshcd_clear_cmd() Sasha Levin
2022-06-28 2:18 ` [PATCH AUTOSEL 5.18 15/53] scsi: ufs: Support clearing multiple commands at once Sasha Levin
@ 2022-06-28 2:18 ` Sasha Levin
2 siblings, 0 replies; 3+ messages in thread
From: Sasha Levin @ 2022-06-28 2:18 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Bart Van Assche, Stanley Chu, Adrian Hunter, Martin K . Petersen,
Sasha Levin, jejb, matthias.bgg, beanhuo, avri.altman,
daejun7.park, linux-scsi, linux-arm-kernel, linux-mediatek
From: Bart Van Assche <bvanassche@acm.org>
[ Upstream commit 2acd76e7b8596e307fcec8fc6bc5fe5ab174749a ]
Prevent that both the interrupt handler and the reset handler try to
complete a request at the same time. This patch is the result of an
analysis of the following crash:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000120
CPU: 0 PID: 0 Comm: swapper/0 Tainted: G OE 5.10.107-android13-4-00051-g1e48e8970cca-ab8664745 #1
pc : ufshcd_release_scsi_cmd+0x30/0x46c
lr : __ufshcd_transfer_req_compl+0x4fc/0x9c0
Call trace:
ufshcd_release_scsi_cmd+0x30/0x46c
__ufshcd_transfer_req_compl+0x4fc/0x9c0
ufshcd_poll+0xf0/0x208
ufshcd_sl_intr+0xb8/0xf0
ufshcd_intr+0x168/0x2f4
__handle_irq_event_percpu+0xa0/0x30c
handle_irq_event+0x84/0x178
handle_fasteoi_irq+0x150/0x2e8
__handle_domain_irq+0x114/0x1e4
gic_handle_irq.31846+0x58/0x300
el1_irq+0xe4/0x1c0
cpuidle_enter_state+0x3ac/0x8c4
do_idle+0x2fc/0x55c
cpu_startup_entry+0x84/0x90
kernel_init+0x0/0x310
start_kernel+0x0/0x608
start_kernel+0x4ec/0x608
Link: https://lore.kernel.org/r/20220613214442.212466-4-bvanassche@acm.org
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/ufs/ufshcd.c | 28 +++++++++++++++++++---------
1 file changed, 19 insertions(+), 9 deletions(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index f08586a4470c..02a122738686 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -6970,14 +6970,14 @@ int ufshcd_exec_raw_upiu_cmd(struct ufs_hba *hba,
}
/**
- * ufshcd_eh_device_reset_handler - device reset handler registered to
- * scsi layer.
+ * ufshcd_eh_device_reset_handler() - Reset a single logical unit.
* @cmd: SCSI command pointer
*
* Returns SUCCESS/FAILED
*/
static int ufshcd_eh_device_reset_handler(struct scsi_cmnd *cmd)
{
+ unsigned long flags, pending_reqs = 0, not_cleared = 0;
struct Scsi_Host *host;
struct ufs_hba *hba;
u32 pos;
@@ -6996,14 +6996,24 @@ static int ufshcd_eh_device_reset_handler(struct scsi_cmnd *cmd)
}
/* clear the commands that were pending for corresponding LUN */
- for_each_set_bit(pos, &hba->outstanding_reqs, hba->nutrs) {
- if (hba->lrb[pos].lun == lun) {
- err = ufshcd_clear_cmds(hba, 1U << pos);
- if (err)
- break;
- __ufshcd_transfer_req_compl(hba, 1U << pos);
- }
+ spin_lock_irqsave(&hba->outstanding_lock, flags);
+ for_each_set_bit(pos, &hba->outstanding_reqs, hba->nutrs)
+ if (hba->lrb[pos].lun == lun)
+ __set_bit(pos, &pending_reqs);
+ hba->outstanding_reqs &= ~pending_reqs;
+ spin_unlock_irqrestore(&hba->outstanding_lock, flags);
+
+ if (ufshcd_clear_cmds(hba, pending_reqs) < 0) {
+ spin_lock_irqsave(&hba->outstanding_lock, flags);
+ not_cleared = pending_reqs &
+ ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
+ hba->outstanding_reqs |= not_cleared;
+ spin_unlock_irqrestore(&hba->outstanding_lock, flags);
+
+ dev_err(hba->dev, "%s: failed to clear requests %#lx\n",
+ __func__, not_cleared);
}
+ __ufshcd_transfer_req_compl(hba, pending_reqs & ~not_cleared);
out:
hba->req_abort_count = 0;
--
2.35.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
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[not found] <20220628021839.594423-1-sashal@kernel.org>
2022-06-28 2:18 ` [PATCH AUTOSEL 5.18 14/53] scsi: ufs: Simplify ufshcd_clear_cmd() Sasha Levin
2022-06-28 2:18 ` [PATCH AUTOSEL 5.18 15/53] scsi: ufs: Support clearing multiple commands at once Sasha Levin
2022-06-28 2:18 ` [PATCH AUTOSEL 5.18 16/53] scsi: ufs: Fix a race between the interrupt handler and the reset handler Sasha Levin
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