On 27/10/2022 02:42, Damien Le Moal wrote:
On 10/25/22 19:32, John Garry wrote:Add a function to handle queued ATA internal SCSI cmnds - does much the same as ata_exec_internal_sg() does (which will be fixed up later to actually queue internal cmnds through this function). Signed-off-by: John Garry <john.garry@xxxxxxxxxx> --- drivers/ata/libata-sata.c | 3 +++ drivers/ata/libata-scsi.c | 43 +++++++++++++++++++++++++++++++++++++++ drivers/ata/libata.h | 3 ++- include/linux/libata.h | 6 ++++++ 4 files changed, 54 insertions(+), 1 deletion(-) diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c index b6806d41a8c5..e8b828c56542 100644 --- a/drivers/ata/libata-sata.c +++ b/drivers/ata/libata-sata.c @@ -1258,6 +1258,9 @@ int ata_sas_queuecmd(struct scsi_cmnd *cmd, struct ata_port *ap) { int rc = 0;+ if (blk_mq_is_reserved_rq(scsi_cmd_to_rq(cmd)))+ return ata_scsi_queue_internal(cmd, ap->link.device); + if (likely(ata_dev_enabled(ap->link.device))) rc = __ata_scsi_queuecmd(cmd, ap->link.device); else { diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index 476e0ef4bd29..30d7c90b0c35 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -3965,6 +3965,49 @@ static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd) return NULL; }+unsigned int ata_scsi_queue_internal(struct scsi_cmnd *scmd,+ struct ata_device *dev) +{ + struct ata_link *link = dev->link; + struct ata_port *ap = link->ap; + struct ata_queued_cmd *qc; + + /* no internal command while frozen */ + if (ap->pflags & ATA_PFLAG_FROZEN) + goto did_err; + + /* initialize internal qc */ + qc = __ata_qc_from_tag(ap, ATA_TAG_INTERNAL); + link->preempted_tag = link->active_tag; + link->preempted_sactive = link->sactive; + ap->preempted_qc_active = ap->qc_active; + ap->preempted_nr_active_links = ap->nr_active_links; + link->active_tag = ATA_TAG_POISON; + link->sactive = 0; + ap->qc_active = 0; + ap->nr_active_links = 0; + + if (qc->dma_dir != DMA_NONE) { + int n_elem; + + n_elem = 1; + qc->n_elem = n_elem; + qc->sg = scsi_sglist(scmd); + qc->nbytes = qc->sg->length; + ata_sg_init(qc, qc->sg, n_elem); + } + + scmd->submitter = SUBMITTED_BY_BLOCK_LAYER; + + ata_qc_issue(qc);Arg, no ! This potentially mixes NCQ and non-NCQ commands, which is forbidden by ATA spec. You need to use something like: if (ap->ops->qc_defer) { if ((rc = ap->ops->qc_defer(qc))) goto defer; } ata_qc_issue(qc); which is done in __ata_scsi_queuecmd() -> ata_scsi_translate() Unless you guarantee that ata_scsi_queue_internal() is always called from libata EH context ?
This will be called synchronously called from ata_exec_internal_sg(), so the same rules on NCQ vs non-NCQ would apply here. As I see, ata_exec_internal_sg() assumes non-NCQ mode and is not multi-thread safe.
Thanks, John
+ + return 0; +did_err: + scmd->result = (DID_ERROR << 16); + scsi_done(scmd); + return 0; +} + int __ata_scsi_queuecmd(struct scsi_cmnd *scmd, struct ata_device *dev) { u8 scsi_op = scmd->cmnd[0]; diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h index 0c2df1e60768..15cd1cd618b8 100644 --- a/drivers/ata/libata.h +++ b/drivers/ata/libata.h @@ -82,7 +82,6 @@ extern int ata_port_probe(struct ata_port *ap); extern void __ata_port_probe(struct ata_port *ap); extern unsigned int ata_read_log_page(struct ata_device *dev, u8 log, u8 page, void *buf, unsigned int sectors); - #define to_ata_port(d) container_of(d, struct ata_port, tdev)/* libata-acpi.c */@@ -130,6 +129,8 @@ extern int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel, void ata_scsi_sdev_config(struct scsi_device *sdev); int ata_scsi_dev_config(struct scsi_device *sdev, struct ata_device *dev); int __ata_scsi_queuecmd(struct scsi_cmnd *scmd, struct ata_device *dev); +unsigned int ata_scsi_queue_internal(struct scsi_cmnd *scmd, + struct ata_device *dev);/* libata-eh.c */extern unsigned int ata_internal_cmd_timeout(struct ata_device *dev, u8 cmd); diff --git a/include/linux/libata.h b/include/linux/libata.h index 827d5838cd23..8938b584520f 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -764,7 +764,9 @@ struct ata_link {struct device tdev;unsigned int active_tag; /* active tag on this link */ + unsigned int preempted_tag; u32 sactive; /* active NCQ commands */ + u32 preempted_sactive;unsigned int flags; /* ATA_LFLAG_xxx */ @@ -857,6 +859,10 @@ struct ata_port {#ifdef CONFIG_ATA_ACPI struct ata_acpi_gtm __acpi_init_gtm; /* use ata_acpi_init_gtm() */ #endif + + u64 preempted_qc_active; + int preempted_nr_active_links; + /* owned by EH */ u8 sector_buf[ATA_SECT_SIZE] ____cacheline_aligned; };
