+++ /dev/null
-From 0a36371573b62927d8121620e42c8291081747f0 Mon Sep 17 00:00:00 2001
-From: Sasha Levin <sashal@kernel.org>
-Date: Thu, 30 Jun 2022 12:57:03 -0700
-Subject: scsi: sd: Rework asynchronous resume support
-
-From: Bart Van Assche <bvanassche@acm.org>
-
-[ Upstream commit 88f1669019bd62b3009a3cebf772fbaaa21b9f38 ]
-
-For some technologies, e.g. an ATA bus, resuming can take multiple
-seconds. Waiting for resume to finish can cause a very noticeable delay.
-Hence this commit that restores the behavior from before "scsi: core: pm:
-Rely on the device driver core for async power management" for most SCSI
-devices.
-
-This commit introduces a behavior change: if the START command fails, do
-not consider this as a SCSI disk resume failure.
-
-Link: https://bugzilla.kernel.org/show_bug.cgi?id=215880
-Link: https://lore.kernel.org/r/20220630195703.10155-3-bvanassche@acm.org
-Fixes: a19a93e4c6a9 ("scsi: core: pm: Rely on the device driver core for async power management")
-Cc: Ming Lei <ming.lei@redhat.com>
-Cc: Hannes Reinecke <hare@suse.de>
-Cc: John Garry <john.garry@huawei.com>
-Cc: ericspero@icloud.com
-Cc: jason600.groome@gmail.com
-Tested-by: jason600.groome@gmail.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/sd.c | 84 +++++++++++++++++++++++++++++++++++++----------
- drivers/scsi/sd.h | 5 +++
- 2 files changed, 71 insertions(+), 18 deletions(-)
-
-diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
-index a1a2ac09066f..081e39b3543b 100644
---- a/drivers/scsi/sd.c
-+++ b/drivers/scsi/sd.c
-@@ -103,6 +103,7 @@ static void sd_config_discard(struct scsi_disk *, unsigned int);
- static void sd_config_write_same(struct scsi_disk *);
- static int sd_revalidate_disk(struct gendisk *);
- static void sd_unlock_native_capacity(struct gendisk *disk);
-+static void sd_start_done_work(struct work_struct *work);
- static int sd_probe(struct device *);
- static int sd_remove(struct device *);
- static void sd_shutdown(struct device *);
-@@ -3463,6 +3464,7 @@ static int sd_probe(struct device *dev)
- sdkp->max_retries = SD_MAX_RETRIES;
- atomic_set(&sdkp->openers, 0);
- atomic_set(&sdkp->device->ioerr_cnt, 0);
-+ INIT_WORK(&sdkp->start_done_work, sd_start_done_work);
-
- if (!sdp->request_queue->rq_timeout) {
- if (sdp->type != TYPE_MOD)
-@@ -3585,12 +3587,69 @@ static void scsi_disk_release(struct device *dev)
- kfree(sdkp);
- }
-
-+/* Process sense data after a START command finished. */
-+static void sd_start_done_work(struct work_struct *work)
-+{
-+ struct scsi_disk *sdkp = container_of(work, typeof(*sdkp),
-+ start_done_work);
-+ struct scsi_sense_hdr sshdr;
-+ int res = sdkp->start_result;
-+
-+ if (res == 0)
-+ return;
-+
-+ sd_print_result(sdkp, "Start/Stop Unit failed", res);
-+
-+ if (res < 0)
-+ return;
-+
-+ if (scsi_normalize_sense(sdkp->start_sense_buffer,
-+ sdkp->start_sense_len, &sshdr))
-+ sd_print_sense_hdr(sdkp, &sshdr);
-+}
-+
-+/* A START command finished. May be called from interrupt context. */
-+static void sd_start_done(struct request *req, blk_status_t status)
-+{
-+ const struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
-+ struct scsi_disk *sdkp = scsi_disk(req->q->disk);
-+
-+ sdkp->start_result = scmd->result;
-+ WARN_ON_ONCE(scmd->sense_len > SCSI_SENSE_BUFFERSIZE);
-+ sdkp->start_sense_len = scmd->sense_len;
-+ memcpy(sdkp->start_sense_buffer, scmd->sense_buffer,
-+ ARRAY_SIZE(sdkp->start_sense_buffer));
-+ WARN_ON_ONCE(!schedule_work(&sdkp->start_done_work));
-+}
-+
-+/* Submit a START command asynchronously. */
-+static int sd_submit_start(struct scsi_disk *sdkp, u8 cmd[], u8 cmd_len)
-+{
-+ struct scsi_device *sdev = sdkp->device;
-+ struct request_queue *q = sdev->request_queue;
-+ struct request *req;
-+ struct scsi_cmnd *scmd;
-+
-+ req = scsi_alloc_request(q, REQ_OP_DRV_IN, BLK_MQ_REQ_PM);
-+ if (IS_ERR(req))
-+ return PTR_ERR(req);
-+
-+ scmd = blk_mq_rq_to_pdu(req);
-+ scmd->cmd_len = cmd_len;
-+ memcpy(scmd->cmnd, cmd, cmd_len);
-+ scmd->allowed = sdkp->max_retries;
-+ req->timeout = SD_TIMEOUT;
-+ req->rq_flags |= RQF_PM | RQF_QUIET;
-+ req->end_io = sd_start_done;
-+ blk_execute_rq_nowait(req, /*at_head=*/true);
-+
-+ return 0;
-+}
-+
- static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
- {
- unsigned char cmd[6] = { START_STOP }; /* START_VALID */
-- struct scsi_sense_hdr sshdr;
- struct scsi_device *sdp = sdkp->device;
-- int res;
-
- if (start)
- cmd[4] |= 1; /* START */
-@@ -3601,23 +3660,10 @@ static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
- if (!scsi_device_online(sdp))
- return -ENODEV;
-
-- res = scsi_execute(sdp, cmd, DMA_NONE, NULL, 0, NULL, &sshdr,
-- SD_TIMEOUT, sdkp->max_retries, 0, RQF_PM, NULL);
-- if (res) {
-- sd_print_result(sdkp, "Start/Stop Unit failed", res);
-- if (res > 0 && scsi_sense_valid(&sshdr)) {
-- sd_print_sense_hdr(sdkp, &sshdr);
-- /* 0x3a is medium not present */
-- if (sshdr.asc == 0x3a)
-- res = 0;
-- }
-- }
-+ /* Wait until processing of sense data has finished. */
-+ flush_work(&sdkp->start_done_work);
-
-- /* SCSI error codes must not go to the generic layer */
-- if (res)
-- return -EIO;
--
-- return 0;
-+ return sd_submit_start(sdkp, cmd, sizeof(cmd));
- }
-
- /*
-@@ -3644,6 +3690,8 @@ static void sd_shutdown(struct device *dev)
- sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
- sd_start_stop_device(sdkp, 0);
- }
-+
-+ flush_work(&sdkp->start_done_work);
- }
-
- static int sd_suspend_common(struct device *dev, bool ignore_stop_errors)
-diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h
-index 5eea762f84d1..b89187761d61 100644
---- a/drivers/scsi/sd.h
-+++ b/drivers/scsi/sd.h
-@@ -150,6 +150,11 @@ struct scsi_disk {
- unsigned urswrz : 1;
- unsigned security : 1;
- unsigned ignore_medium_access_errors : 1;
-+
-+ int start_result;
-+ u32 start_sense_len;
-+ u8 start_sense_buffer[SCSI_SENSE_BUFFERSIZE];
-+ struct work_struct start_done_work;
- };
- #define to_scsi_disk(obj) container_of(obj, struct scsi_disk, disk_dev)
-
---
-2.35.1
-
projects / thirdparty / kernel / stable-queue.git / commitdiff
