From 5d1952acd0d56f6b6835aa45bea763ee97b9e66f Mon Sep 17 00:00:00 2001 From: Uma Krishnan Date: Fri, 4 Mar 2016 15:55:18 -0600 Subject: [PATCH] cxlflash: Reorder user context initialization In order to support cxlflash in the PowerVM environment, underlying hypervisor APIs have imposed a kernel API ordering change. For the superpipe access to LUN, user applications need a context. The cxlflash module creates this context by making a sequence of cxl calls. In the current code, a context is initialized via cxl_dev_context_init() followed by cxl_process_element(), a function that obtains the process element id. Finally, cxl_start_work() is called to attach the process element. In the PowerVM environment, a process element id cannot be obtained from the hypervisor until the process element is attached. The cxlflash module is unable to create contexts without a valid process element id. To fix this problem, cxl_start_work() is called before obtaining the process element id. Signed-off-by: Uma Krishnan Acked-by: Matthew R. Ochs Signed-off-by: Martin K. Petersen --- drivers/scsi/cxlflash/superpipe.c | 56 +++++++++++++++---------------- 1 file changed, 28 insertions(+), 28 deletions(-) diff --git a/drivers/scsi/cxlflash/superpipe.c b/drivers/scsi/cxlflash/superpipe.c index 7ec0b7a92876..d8a5cb3cd2bd 100644 --- a/drivers/scsi/cxlflash/superpipe.c +++ b/drivers/scsi/cxlflash/superpipe.c @@ -1386,6 +1386,13 @@ static int cxlflash_disk_attach(struct scsi_device *sdev, goto out_attach; } + ctxi = create_context(cfg); + if (unlikely(!ctxi)) { + dev_err(dev, "%s: Failed to create context! (%d)\n", + __func__, ctxid); + goto err; + } + ctx = cxl_dev_context_init(cfg->dev); if (IS_ERR_OR_NULL(ctx)) { dev_err(dev, "%s: Could not initialize context %p\n", @@ -1394,6 +1401,17 @@ static int cxlflash_disk_attach(struct scsi_device *sdev, goto err; } + work = &ctxi->work; + work->num_interrupts = attach->num_interrupts; + work->flags = CXL_START_WORK_NUM_IRQS; + + rc = cxl_start_work(ctx, work); + if (unlikely(rc)) { + dev_dbg(dev, "%s: Could not start context rc=%d\n", + __func__, rc); + goto err; + } + ctxid = cxl_process_element(ctx); if (unlikely((ctxid >= MAX_CONTEXT) || (ctxid < 0))) { dev_err(dev, "%s: ctxid (%d) invalid!\n", __func__, ctxid); @@ -1411,27 +1429,9 @@ 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); - if (unlikely(!ctxi)) { - dev_err(dev, "%s: Failed to create context! (%d)\n", - __func__, ctxid); - goto err; - } - /* 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; - - rc = cxl_start_work(ctx, work); - if (unlikely(rc)) { - dev_dbg(dev, "%s: Could not start context rc=%d\n", - __func__, rc); - goto err; - } - rc = afu_attach(cfg, ctxi); if (unlikely(rc)) { dev_err(dev, "%s: Could not attach AFU rc %d\n", __func__, rc); @@ -1532,24 +1532,24 @@ static int recover_context(struct cxlflash_cfg *cfg, struct ctx_info *ctxi) goto out; } + rc = cxl_start_work(ctx, &ctxi->work); + if (unlikely(rc)) { + dev_dbg(dev, "%s: Could not start context rc=%d\n", + __func__, rc); + goto err1; + } + ctxid = cxl_process_element(ctx); if (unlikely((ctxid >= MAX_CONTEXT) || (ctxid < 0))) { dev_err(dev, "%s: ctxid (%d) invalid!\n", __func__, ctxid); rc = -EPERM; - goto err1; + goto err2; } file = cxl_get_fd(ctx, &cfg->cxl_fops, &fd); if (unlikely(fd < 0)) { rc = -ENODEV; dev_err(dev, "%s: Could not get file descriptor\n", __func__); - goto err1; - } - - rc = cxl_start_work(ctx, &ctxi->work); - if (unlikely(rc)) { - dev_dbg(dev, "%s: Could not start context rc=%d\n", - __func__, rc); goto err2; } @@ -1594,10 +1594,10 @@ out: return rc; err3: - cxl_stop_context(ctx); -err2: fput(file); put_unused_fd(fd); +err2: + cxl_stop_context(ctx); err1: cxl_release_context(ctx); goto out; -- 2.30.2