From 2cb79266d6b229dbebd31fe114af1bdab25c8076 Mon Sep 17 00:00:00 2001 From: "Matthew R. Ochs" Date: Thu, 13 Aug 2015 21:47:53 -0500 Subject: cxlflash: Virtual LUN support Add support for physical LUN segmentation (virtual LUNs) to device driver supporting the IBM CXL Flash adapter. This patch allows user space applications to virtually segment a physical LUN into N virtual LUNs, taking advantage of the translation features provided by this adapter. Signed-off-by: Matthew R. Ochs Signed-off-by: Manoj N. Kumar Reviewed-by: Michael Neuling Reviewed-by: Wen Xiong Signed-off-by: James Bottomley --- drivers/scsi/cxlflash/superpipe.c | 82 ++++++++++++++++++++++++++++++++++++--- 1 file changed, 76 insertions(+), 6 deletions(-) (limited to 'drivers/scsi/cxlflash/superpipe.c') diff --git a/drivers/scsi/cxlflash/superpipe.c b/drivers/scsi/cxlflash/superpipe.c index 3c8bce8bbb0b..f1b62cea75b1 100644 --- a/drivers/scsi/cxlflash/superpipe.c +++ b/drivers/scsi/cxlflash/superpipe.c @@ -26,10 +26,24 @@ #include "sislite.h" #include "common.h" +#include "vlun.h" #include "superpipe.h" struct cxlflash_global global; +/** + * marshal_rele_to_resize() - translate release to resize structure + * @rele: Source structure from which to translate/copy. + * @resize: Destination structure for the translate/copy. + */ +static void marshal_rele_to_resize(struct dk_cxlflash_release *release, + struct dk_cxlflash_resize *resize) +{ + resize->hdr = release->hdr; + resize->context_id = release->context_id; + resize->rsrc_handle = release->rsrc_handle; +} + /** * marshal_det_to_rele() - translate detach to release structure * @detach: Destination structure for the translate/copy. @@ -449,6 +463,7 @@ void rhte_checkin(struct ctx_info *ctxi, rhte->fp = 0; ctxi->rht_out--; ctxi->rht_lun[rsrc_handle] = NULL; + ctxi->rht_needs_ws[rsrc_handle] = false; } /** @@ -526,13 +541,21 @@ out: /** * cxlflash_lun_detach() - detaches a user from a LUN and resets the LUN's mode * @gli: LUN to detach. + * + * When resetting the mode, terminate block allocation resources as they + * are no longer required (service is safe to call even when block allocation + * resources were not present - such as when transitioning from physical mode). + * These resources will be reallocated when needed (subsequent transition to + * virtual mode). */ void cxlflash_lun_detach(struct glun_info *gli) { mutex_lock(&gli->mutex); WARN_ON(gli->mode == MODE_NONE); - if (--gli->users == 0) + if (--gli->users == 0) { gli->mode = MODE_NONE; + cxlflash_ba_terminate(&gli->blka.ba_lun); + } pr_debug("%s: gli->users=%u\n", __func__, gli->users); WARN_ON(gli->users < 0); mutex_unlock(&gli->mutex); @@ -544,10 +567,12 @@ void cxlflash_lun_detach(struct glun_info *gli) * @ctxi: Context owning resources. * @release: Release ioctl data structure. * - * Note that the AFU sync should _not_ be performed when the context is sitting - * on the error recovery list. A context on the error recovery list is not known - * to the AFU due to reset. When the context is recovered, it will be reattached - * and made known again to the AFU. + * For LUNs in virtual mode, the virtual LUN associated with the specified + * resource handle is resized to 0 prior to releasing the RHTE. Note that the + * AFU sync should _not_ be performed when the context is sitting on the error + * recovery list. A context on the error recovery list is not known to the AFU + * due to reset. When the context is recovered, it will be reattached and made + * known again to the AFU. * * Return: 0 on success, -errno on failure */ @@ -562,6 +587,7 @@ int _cxlflash_disk_release(struct scsi_device *sdev, struct afu *afu = cfg->afu; bool put_ctx = false; + struct dk_cxlflash_resize size; res_hndl_t rhndl = release->rsrc_handle; int rc = 0; @@ -594,7 +620,24 @@ int _cxlflash_disk_release(struct scsi_device *sdev, goto out; } + /* + * Resize to 0 for virtual LUNS by setting the size + * to 0. This will clear LXT_START and LXT_CNT fields + * in the RHT entry and properly sync with the AFU. + * + * Afterwards we clear the remaining fields. + */ switch (gli->mode) { + case MODE_VIRTUAL: + marshal_rele_to_resize(release, &size); + size.req_size = 0; + rc = _cxlflash_vlun_resize(sdev, ctxi, &size); + if (rc) { + dev_dbg(dev, "%s: resize failed rc %d\n", __func__, rc); + goto out; + } + + break; case MODE_PHYSICAL: /* * Clear the Format 1 RHT entry for direct access @@ -666,6 +709,7 @@ static void destroy_context(struct cxlflash_cfg *cfg, /* Free memory associated with context */ free_page((ulong)ctxi->rht_start); + kfree(ctxi->rht_needs_ws); kfree(ctxi->rht_lun); kfree(ctxi); atomic_dec_if_positive(&cfg->num_user_contexts); @@ -693,11 +737,13 @@ static struct ctx_info *create_context(struct cxlflash_cfg *cfg, struct afu *afu = cfg->afu; struct ctx_info *ctxi = NULL; struct llun_info **lli = NULL; + bool *ws = NULL; struct sisl_rht_entry *rhte; ctxi = kzalloc(sizeof(*ctxi), GFP_KERNEL); lli = kzalloc((MAX_RHT_PER_CONTEXT * sizeof(*lli)), GFP_KERNEL); - if (unlikely(!ctxi || !lli)) { + ws = kzalloc((MAX_RHT_PER_CONTEXT * sizeof(*ws)), GFP_KERNEL); + if (unlikely(!ctxi || !lli || !ws)) { dev_err(dev, "%s: Unable to allocate context!\n", __func__); goto err; } @@ -709,6 +755,7 @@ 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; @@ -728,6 +775,7 @@ out: return ctxi; err: + kfree(ws); kfree(lli); kfree(ctxi); ctxi = NULL; @@ -1729,6 +1777,12 @@ static int cxlflash_disk_verify(struct scsi_device *sdev, case MODE_PHYSICAL: last_lba = gli->max_lba; break; + case MODE_VIRTUAL: + /* Cast lxt_cnt to u64 for multiply to be treated as 64bit op */ + last_lba = ((u64)rhte->lxt_cnt * MC_CHUNK_SIZE * gli->blk_len); + last_lba /= CXLFLASH_BLOCK_SIZE; + last_lba--; + break; default: WARN(1, "Unsupported LUN mode!"); } @@ -1756,12 +1810,18 @@ static char *decode_ioctl(int cmd) return __stringify_1(DK_CXLFLASH_ATTACH); case DK_CXLFLASH_USER_DIRECT: return __stringify_1(DK_CXLFLASH_USER_DIRECT); + case DK_CXLFLASH_USER_VIRTUAL: + return __stringify_1(DK_CXLFLASH_USER_VIRTUAL); + case DK_CXLFLASH_VLUN_RESIZE: + return __stringify_1(DK_CXLFLASH_VLUN_RESIZE); case DK_CXLFLASH_RELEASE: return __stringify_1(DK_CXLFLASH_RELEASE); case DK_CXLFLASH_DETACH: return __stringify_1(DK_CXLFLASH_DETACH); case DK_CXLFLASH_VERIFY: return __stringify_1(DK_CXLFLASH_VERIFY); + case DK_CXLFLASH_VLUN_CLONE: + return __stringify_1(DK_CXLFLASH_VLUN_CLONE); case DK_CXLFLASH_RECOVER_AFU: return __stringify_1(DK_CXLFLASH_RECOVER_AFU); case DK_CXLFLASH_MANAGE_LUN: @@ -1876,6 +1936,7 @@ static int ioctl_common(struct scsi_device *sdev, int cmd) rc = check_state(cfg); if (unlikely(rc) && (cfg->state == STATE_FAILTERM)) { switch (cmd) { + case DK_CXLFLASH_VLUN_RESIZE: case DK_CXLFLASH_RELEASE: case DK_CXLFLASH_DETACH: dev_dbg(dev, "%s: Command override! (%d)\n", @@ -1923,12 +1984,18 @@ int cxlflash_ioctl(struct scsi_device *sdev, int cmd, void __user *arg) {sizeof(struct dk_cxlflash_verify), (sioctl)cxlflash_disk_verify}, {sizeof(struct dk_cxlflash_recover_afu), (sioctl)cxlflash_afu_recover}, {sizeof(struct dk_cxlflash_manage_lun), (sioctl)cxlflash_manage_lun}, + {sizeof(struct dk_cxlflash_uvirtual), cxlflash_disk_virtual_open}, + {sizeof(struct dk_cxlflash_resize), (sioctl)cxlflash_vlun_resize}, + {sizeof(struct dk_cxlflash_clone), (sioctl)cxlflash_disk_clone}, }; /* Restrict command set to physical support only for internal LUN */ if (afu->internal_lun) switch (cmd) { case DK_CXLFLASH_RELEASE: + case DK_CXLFLASH_USER_VIRTUAL: + case DK_CXLFLASH_VLUN_RESIZE: + case DK_CXLFLASH_VLUN_CLONE: dev_dbg(dev, "%s: %s not supported for lun_mode=%d\n", __func__, decode_ioctl(cmd), afu->internal_lun); rc = -EINVAL; @@ -1942,6 +2009,9 @@ int cxlflash_ioctl(struct scsi_device *sdev, int cmd, void __user *arg) case DK_CXLFLASH_DETACH: case DK_CXLFLASH_VERIFY: case DK_CXLFLASH_RECOVER_AFU: + case DK_CXLFLASH_USER_VIRTUAL: + case DK_CXLFLASH_VLUN_RESIZE: + case DK_CXLFLASH_VLUN_CLONE: dev_dbg(dev, "%s: %s (%08X) on dev(%d/%d/%d/%llu)\n", __func__, decode_ioctl(cmd), cmd, shost->host_no, sdev->channel, sdev->id, sdev->lun); -- cgit v1.2.3