From 5fbb96c8f1ba89fb220efb7e4eeed7cb5112becd Mon Sep 17 00:00:00 2001 From: "Matthew R. Ochs" Date: Mon, 28 Nov 2016 18:42:19 -0600 Subject: [PATCH] scsi: cxlflash: Use cmd_size for private commands Instead of using a private pool of AFU commands, use cmd_size to prime the private pool of SCSI commands such that they are allocated with a size large enough to contain an aligned AFU command. Use scsi_cmd_priv() to derive the aligned/zeroed private command on queuecommand and TMF paths. Remove cmd_checkout() as it is no longer required. The remaining AFU private command infrastructure will be removed in a cleanup commit. Signed-off-by: Matthew R. Ochs Acked-by: Uma Krishnan Signed-off-by: Martin K. Petersen --- drivers/scsi/cxlflash/common.h | 14 ++++++++ drivers/scsi/cxlflash/main.c | 65 ++++++---------------------------- 2 files changed, 25 insertions(+), 54 deletions(-) diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h index 45255145ecd9..539908f65cc4 100644 --- a/drivers/scsi/cxlflash/common.h +++ b/drivers/scsi/cxlflash/common.h @@ -19,6 +19,7 @@ #include #include #include +#include #include extern const struct file_operations cxlflash_cxl_fops; @@ -146,6 +147,19 @@ struct afu_cmd { */ } __aligned(cache_line_size()); +static inline struct afu_cmd *sc_to_afuc(struct scsi_cmnd *sc) +{ + return PTR_ALIGN(scsi_cmd_priv(sc), __alignof__(struct afu_cmd)); +} + +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)); + return afuc; +} + struct afu { /* Stuff requiring alignment go first. */ diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c index 0f13b4de448a..43140ce3163d 100644 --- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -34,38 +34,6 @@ MODULE_AUTHOR("Manoj N. Kumar "); MODULE_AUTHOR("Matthew R. Ochs "); MODULE_LICENSE("GPL"); -/** - * cmd_checkout() - checks out an AFU command - * @afu: AFU to checkout from. - * - * Commands are checked out in a round-robin fashion. Note that since - * the command pool is larger than the hardware queue, the majority of - * times we will only loop once or twice before getting a command. The - * CDB within the command is initialized (zeroed) prior to returning. - * - * Return: The checked out command or NULL when command pool is empty. - */ -static struct afu_cmd *cmd_checkout(struct afu *afu) -{ - int k, dec = CXLFLASH_NUM_CMDS; - struct afu_cmd *cmd; - - while (dec--) { - k = (afu->cmd_couts++ & (CXLFLASH_NUM_CMDS - 1)); - - cmd = &afu->cmd[k]; - - if (!atomic_dec_if_positive(&cmd->free)) { - pr_devel("%s: returning found index=%d cmd=%p\n", - __func__, cmd->slot, cmd); - memset(cmd->rcb.cdb, 0, sizeof(cmd->rcb.cdb)); - return cmd; - } - } - - return NULL; -} - /** * cmd_checkin() - checks in an AFU command * @cmd: AFU command to checkin. @@ -232,7 +200,6 @@ static void cmd_complete(struct afu_cmd *cmd) scp->result = (DID_OK << 16); cmd_is_tmf = cmd->cmd_tmf; - cmd_checkin(cmd); /* Don't use cmd after here */ pr_debug_ratelimited("%s: calling scsi_done scp=%p result=%X " "ioasc=%d\n", __func__, scp, scp->result, @@ -365,7 +332,7 @@ static void wait_resp(struct afu *afu, struct afu_cmd *cmd) */ static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd) { - struct afu_cmd *cmd; + struct afu_cmd *cmd = sc_to_afucz(scp); u32 port_sel = scp->device->channel + 1; short lflag = 0; @@ -376,13 +343,6 @@ static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd) int rc = 0; ulong to; - cmd = cmd_checkout(afu); - if (unlikely(!cmd)) { - dev_err(dev, "%s: could not get a free command\n", __func__); - rc = SCSI_MLQUEUE_HOST_BUSY; - goto out; - } - /* When Task Management Function is active do not send another */ spin_lock_irqsave(&cfg->tmf_slock, lock_flags); if (cfg->tmf_active) @@ -394,6 +354,7 @@ static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd) spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags); cmd->rcb.ctx_id = afu->ctx_hndl; + cmd->rcb.msi = SISL_MSI_RRQ_UPDATED; cmd->rcb.port_sel = port_sel; cmd->rcb.lun_id = lun_to_lunid(scp->device->lun); @@ -402,8 +363,10 @@ static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd) cmd->rcb.req_flags = (SISL_REQ_FLAGS_PORT_LUN_ID | SISL_REQ_FLAGS_SUP_UNDERRUN | lflag); - /* Stash the scp in the reserved field, for reuse during interrupt */ + /* Stash the scp in the command, for reuse during interrupt */ cmd->rcb.scp = scp; + cmd->parent = afu; + spin_lock_init(&cmd->slock); /* Copy the CDB from the cmd passed in */ memcpy(cmd->rcb.cdb, &tmfcmd, sizeof(tmfcmd)); @@ -411,7 +374,6 @@ static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd) /* Send the command */ rc = send_cmd(afu, cmd); if (unlikely(rc)) { - cmd_checkin(cmd); spin_lock_irqsave(&cfg->tmf_slock, lock_flags); cfg->tmf_active = false; spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags); @@ -467,7 +429,7 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp) struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)host->hostdata; struct afu *afu = cfg->afu; struct device *dev = &cfg->dev->dev; - struct afu_cmd *cmd; + struct afu_cmd *cmd = sc_to_afucz(scp); u32 port_sel = scp->device->channel + 1; int nseg, i, ncount; struct scatterlist *sg; @@ -512,17 +474,11 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp) break; } - cmd = cmd_checkout(afu); - if (unlikely(!cmd)) { - dev_err(dev, "%s: could not get a free command\n", __func__); - rc = SCSI_MLQUEUE_HOST_BUSY; - goto out; - } - kref_get(&cfg->afu->mapcount); kref_got = 1; cmd->rcb.ctx_id = afu->ctx_hndl; + cmd->rcb.msi = SISL_MSI_RRQ_UPDATED; cmd->rcb.port_sel = port_sel; cmd->rcb.lun_id = lun_to_lunid(scp->device->lun); @@ -536,6 +492,8 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp) /* Stash the scp in the reserved field, for reuse during interrupt */ cmd->rcb.scp = scp; + cmd->parent = afu; + spin_lock_init(&cmd->slock); nseg = scsi_dma_map(scp); if (unlikely(nseg < 0)) { @@ -556,10 +514,8 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp) /* Send the command */ rc = send_cmd(afu, cmd); - if (unlikely(rc)) { - cmd_checkin(cmd); + if (unlikely(rc)) scsi_dma_unmap(scp); - } out: if (kref_got) @@ -2314,6 +2270,7 @@ static struct scsi_host_template driver_template = { .change_queue_depth = cxlflash_change_queue_depth, .cmd_per_lun = CXLFLASH_MAX_CMDS_PER_LUN, .can_queue = CXLFLASH_MAX_CMDS, + .cmd_size = sizeof(struct afu_cmd) + __alignof__(struct afu_cmd) - 1, .this_id = -1, .sg_tablesize = 1, /* No scatter gather support */ .max_sectors = CXLFLASH_MAX_SECTORS, -- 2.20.1