diff --git a/drivers/scsi/cxlflash/superpipe.c b/drivers/scsi/cxlflash/superpipe.c index f4020dbb55c3..b30b362318fa 100644 --- a/drivers/scsi/cxlflash/superpipe.c +++ b/drivers/scsi/cxlflash/superpipe.c @@ -709,27 +709,32 @@ int cxlflash_disk_release(struct scsi_device *sdev, * @cfg: Internal structure associated with the host. * @ctxi: Context to release. * - * Note that the rht_lun member of the context was cut from a single - * allocation when the context was created and therefore does not need - * to be explicitly freed. Also note that we conditionally check for the - * existence of the context control map before clearing the RHT registers - * and context capabilities because it is possible to destroy a context - * while the context is in the error state (previous mapping was removed - * [so we don't have to worry about clearing] and context is waiting for - * a new mapping). + * This routine is safe to be called with a a non-initialized context + * and is tolerant of being called with the context's mutex held (it + * will be unlocked if necessary before freeing). Also note that the + * routine conditionally checks for the existence of the context control + * map before clearing the RHT registers and context capabilities because + * it is possible to destroy a context while the context is in the error + * state (previous mapping was removed [so there is no need to worry about + * clearing] and context is waiting for a new mapping). */ static void destroy_context(struct cxlflash_cfg *cfg, struct ctx_info *ctxi) { struct afu *afu = cfg->afu; - WARN_ON(!list_empty(&ctxi->luns)); + if (ctxi->initialized) { + WARN_ON(!list_empty(&ctxi->luns)); - /* Clear RHT registers and drop all capabilities for this context */ - if (afu->afu_map && ctxi->ctrl_map) { - writeq_be(0, &ctxi->ctrl_map->rht_start); - writeq_be(0, &ctxi->ctrl_map->rht_cnt_id); - writeq_be(0, &ctxi->ctrl_map->ctx_cap); + /* Clear RHT registers and drop all capabilities for context */ + if (afu->afu_map && ctxi->ctrl_map) { + writeq_be(0, &ctxi->ctrl_map->rht_start); + writeq_be(0, &ctxi->ctrl_map->rht_cnt_id); + writeq_be(0, &ctxi->ctrl_map->ctx_cap); + } + + if (mutex_is_locked(&ctxi->mutex)) + mutex_unlock(&ctxi->mutex); } /* Free memory associated with context */ @@ -742,23 +747,12 @@ static void destroy_context(struct cxlflash_cfg *cfg, /** * create_context() - allocates and initializes a context * @cfg: Internal structure associated with the host. - * @ctx: Previously obtained CXL context reference. - * @ctxid: Previously obtained process element associated with CXL context. - * @adap_fd: Previously obtained adapter fd associated with CXL context. - * @file: Previously obtained file associated with CXL context. - * @perms: User-specified permissions. - * - * The context's mutex is locked when an allocated context is returned. * * Return: Allocated context on success, NULL on failure */ -static struct ctx_info *create_context(struct cxlflash_cfg *cfg, - struct cxl_context *ctx, int ctxid, - int adap_fd, struct file *file, - u32 perms) +static struct ctx_info *create_context(struct cxlflash_cfg *cfg) { struct device *dev = &cfg->dev->dev; - struct afu *afu = cfg->afu; struct ctx_info *ctxi = NULL; struct llun_info **lli = NULL; u8 *ws = NULL; @@ -781,19 +775,6 @@ static struct ctx_info *create_context(struct cxlflash_cfg *cfg, ctxi->rht_lun = lli; ctxi->rht_needs_ws = ws; ctxi->rht_start = rhte; - ctxi->rht_perms = perms; - - ctxi->ctrl_map = &afu->afu_map->ctrls[ctxid].ctrl; - ctxi->ctxid = ENCODE_CTXID(ctxi, ctxid); - ctxi->lfd = adap_fd; - ctxi->pid = current->tgid; /* tgid = pid */ - ctxi->ctx = ctx; - ctxi->file = file; - mutex_init(&ctxi->mutex); - INIT_LIST_HEAD(&ctxi->luns); - INIT_LIST_HEAD(&ctxi->list); /* initialize for list_empty() */ - - mutex_lock(&ctxi->mutex); out: return ctxi; @@ -805,6 +786,40 @@ err: goto out; } +/** + * init_context() - initializes a previously allocated context + * @ctxi: Previously allocated context + * @cfg: Internal structure associated with the host. + * @ctx: Previously obtained CXL context reference. + * @ctxid: Previously obtained process element associated with CXL context. + * @adap_fd: Previously obtained adapter fd associated with CXL context. + * @file: Previously obtained file associated with CXL context. + * @perms: User-specified permissions. + * + * Upon return, the context is marked as initialized and the context's mutex + * is locked. + */ +static void init_context(struct ctx_info *ctxi, struct cxlflash_cfg *cfg, + struct cxl_context *ctx, int ctxid, int adap_fd, + struct file *file, u32 perms) +{ + struct afu *afu = cfg->afu; + + ctxi->rht_perms = perms; + ctxi->ctrl_map = &afu->afu_map->ctrls[ctxid].ctrl; + ctxi->ctxid = ENCODE_CTXID(ctxi, ctxid); + ctxi->lfd = adap_fd; + ctxi->pid = current->tgid; /* tgid = pid */ + ctxi->ctx = ctx; + ctxi->file = file; + ctxi->initialized = true; + mutex_init(&ctxi->mutex); + INIT_LIST_HEAD(&ctxi->luns); + INIT_LIST_HEAD(&ctxi->list); /* initialize for list_empty() */ + + mutex_lock(&ctxi->mutex); +} + /** * _cxlflash_disk_detach() - detaches a LUN from a context * @sdev: SCSI device associated with LUN. @@ -1396,13 +1411,16 @@ static int cxlflash_disk_attach(struct scsi_device *sdev, /* Translate read/write O_* flags from fcntl.h to AFU permission bits */ perms = SISL_RHT_PERM(attach->hdr.flags + 1); - ctxi = create_context(cfg, ctx, ctxid, fd, file, perms); + ctxi = create_context(cfg); if (unlikely(!ctxi)) { dev_err(dev, "%s: Failed to create context! (%d)\n", __func__, ctxid); goto err3; } + /* Context mutex is locked upon return */ + init_context(ctxi, cfg, ctx, ctxid, fd, file, perms); + work = &ctxi->work; work->num_interrupts = attach->num_interrupts; work->flags = CXL_START_WORK_NUM_IRQS; diff --git a/drivers/scsi/cxlflash/superpipe.h b/drivers/scsi/cxlflash/superpipe.h index bede574bcd77..5f9a091fda95 100644 --- a/drivers/scsi/cxlflash/superpipe.h +++ b/drivers/scsi/cxlflash/superpipe.h @@ -102,6 +102,7 @@ struct ctx_info { u64 ctxid; int lfd; pid_t pid; + bool initialized; bool unavail; bool err_recovery_active; struct mutex mutex; /* Context protection */