From: Uma Krishnan Date: Fri, 7 Jul 2017 16:05:45 +0000 (-0300) Subject: scsi: cxlflash: Flush pending commands in cleanup path X-Git-Tag: Ubuntu-4.10.0-29.33~28 X-Git-Url: https://git.proxmox.com/?p=mirror_ubuntu-zesty-kernel.git;a=commitdiff_plain;h=2450a5e30dc493c96014479d45b9bb30dd572b63 scsi: cxlflash: Flush pending commands in cleanup path BugLink: http://bugs.launchpad.net/bugs/1702521 When the AFU is reset in an error path, pending scsi commands can be silently dropped without completion or a formal abort. This puts the onus on the cxlflash driver to notify mid-layer and indicating that the command can be retried. Once the card has been quiesced, the hardware send queue lock is acquired to prevent any data movement while the pending commands are processed. Signed-off-by: Uma Krishnan Acked-by: Matthew R. Ochs Signed-off-by: Martin K. Petersen (cherry picked from commit a1ea04b3ebd9ae5c1cd5bf48be37aba0d93c1acc) Signed-off-by: Victor Aoqui Acked-by: Stefan Bader Acked-by: Seth Forshee Signed-off-by: Thadeu Lima de Souza Cascardo --- diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h index 3eaa3be43d24..11a5b0a10a34 100644 --- a/drivers/scsi/cxlflash/common.h +++ b/drivers/scsi/cxlflash/common.h @@ -157,7 +157,9 @@ struct afu_cmd { struct list_head queue; u32 hwq_index; - u8 cmd_tmf:1; + u8 cmd_tmf:1, + cmd_aborted:1; + struct list_head list; /* Pending commands link */ /* As per the SISLITE spec the IOARCB EA has to be 16-byte aligned. @@ -176,6 +178,7 @@ static inline struct afu_cmd *sc_to_afucz(struct scsi_cmnd *sc) struct afu_cmd *afuc = sc_to_afuc(sc); memset(afuc, 0, sizeof(*afuc)); + INIT_LIST_HEAD(&afuc->queue); return afuc; } diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c index 1446fabe4cf6..0a3de42310ec 100644 --- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -193,6 +193,36 @@ static void cmd_complete(struct afu_cmd *cmd) complete(&cmd->cevent); } +/** + * flush_pending_cmds() - flush all pending commands on this hardware queue + * @hwq: Hardware queue to flush. + * + * The hardware send queue lock associated with this hardware queue must be + * held when calling this routine. + */ +static void flush_pending_cmds(struct hwq *hwq) +{ + struct afu_cmd *cmd, *tmp; + struct scsi_cmnd *scp; + + list_for_each_entry_safe(cmd, tmp, &hwq->pending_cmds, list) { + /* Bypass command when on a doneq, cmd_complete() will handle */ + if (!list_empty(&cmd->queue)) + continue; + + list_del(&cmd->list); + + if (cmd->scp) { + scp = cmd->scp; + scp->result = (DID_IMM_RETRY << 16); + scp->scsi_done(scp); + } else { + cmd->cmd_aborted = true; + complete(&cmd->cevent); + } + } +} + /** * context_reset() - reset context via specified register * @hwq: Hardware queue owning the context to be reset. @@ -357,6 +387,9 @@ static int wait_resp(struct afu *afu, struct afu_cmd *cmd) if (!timeout) rc = -ETIMEDOUT; + if (cmd->cmd_aborted) + rc = -EAGAIN; + if (unlikely(cmd->sa.ioasc != 0)) { dev_err(dev, "%s: cmd %02x failed, ioasc=%08x\n", __func__, cmd->rcb.cdb[0], cmd->sa.ioasc); @@ -702,6 +735,7 @@ static void term_mc(struct cxlflash_cfg *cfg, u32 index) struct afu *afu = cfg->afu; struct device *dev = &cfg->dev->dev; struct hwq *hwq; + ulong lock_flags; if (!afu) { dev_err(dev, "%s: returning with NULL afu\n", __func__); @@ -719,6 +753,10 @@ static void term_mc(struct cxlflash_cfg *cfg, u32 index) if (index != PRIMARY_HWQ) WARN_ON(cxl_release_context(hwq->ctx)); hwq->ctx = NULL; + + spin_lock_irqsave(&hwq->hsq_slock, lock_flags); + flush_pending_cmds(hwq); + spin_unlock_irqrestore(&hwq->hsq_slock, lock_flags); } /** @@ -2155,7 +2193,7 @@ int cxlflash_afu_sync(struct afu *afu, ctx_hndl_t ctx_hndl_u, mutex_lock(&sync_active); atomic_inc(&afu->cmds_active); - buf = kzalloc(sizeof(*cmd) + __alignof__(*cmd) - 1, GFP_KERNEL); + buf = kmalloc(sizeof(*cmd) + __alignof__(*cmd) - 1, GFP_KERNEL); if (unlikely(!buf)) { dev_err(dev, "%s: no memory for command\n", __func__); rc = -ENOMEM; @@ -2165,6 +2203,8 @@ int cxlflash_afu_sync(struct afu *afu, ctx_hndl_t ctx_hndl_u, cmd = (struct afu_cmd *)PTR_ALIGN(buf, __alignof__(*cmd)); retry: + memset(cmd, 0, sizeof(*cmd)); + INIT_LIST_HEAD(&cmd->queue); init_completion(&cmd->cevent); cmd->parent = afu; cmd->hwq_index = hwq->index; @@ -2191,11 +2231,20 @@ retry: } rc = wait_resp(afu, cmd); - if (rc == -ETIMEDOUT) { + switch (rc) { + case -ETIMEDOUT: rc = afu->context_reset(hwq); - if (!rc && ++nretry < 2) + if (rc) { + cxlflash_schedule_async_reset(cfg); + break; + } + /* fall through to retry */ + case -EAGAIN: + if (++nretry < 2) goto retry; - cxlflash_schedule_async_reset(cfg); + /* fall through to exit */ + default: + break; } out: