From: Uma Krishnan Date: Thu, 22 Jun 2017 02:14:30 +0000 (-0500) Subject: scsi: cxlflash: Handle AFU sync failures X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c2c292f45029a6850cd14c7c2fa4fc479b8f74aa;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git scsi: cxlflash: Handle AFU sync failures AFU sync operations are not currently evaluated for failure. This is acceptable for paths where there is not a dependency on the AFU being consistent with the host. Examples include link reset events and LUN cleanup operations. On paths where there is a dependency, such as a LUN open, a sync failure should be acted upon. In the event of AFU sync failures, either log or cleanup as appropriate for operations that are dependent on a successful sync completion. Update documentation to reflect behavior in the event of an AFU sync failure. Signed-off-by: Uma Krishnan Acked-by: Matthew R. Ochs Signed-off-by: Martin K. Petersen --- diff --git a/Documentation/powerpc/cxlflash.txt b/Documentation/powerpc/cxlflash.txt index 66b4496d6619..f9036cb0170d 100644 --- a/Documentation/powerpc/cxlflash.txt +++ b/Documentation/powerpc/cxlflash.txt @@ -257,6 +257,12 @@ DK_CXLFLASH_VLUN_RESIZE operating in the virtual mode and used to program a LUN translation table that the AFU references when provided with a resource handle. + This ioctl can return -EAGAIN if an AFU sync operation takes too long. + In addition to returning a failure to user, cxlflash will also schedule + an asynchronous AFU reset. Should the user choose to retry the operation, + it is expected to succeed. If this ioctl fails with -EAGAIN, the user + can either retry the operation or treat it as a failure. + DK_CXLFLASH_RELEASE ------------------- This ioctl is responsible for releasing a previously obtained @@ -309,6 +315,12 @@ DK_CXLFLASH_VLUN_CLONE clone. This is to avoid a stale entry in the file descriptor table of the child process. + This ioctl can return -EAGAIN if an AFU sync operation takes too long. + In addition to returning a failure to user, cxlflash will also schedule + an asynchronous AFU reset. Should the user choose to retry the operation, + it is expected to succeed. If this ioctl fails with -EAGAIN, the user + can either retry the operation or treat it as a failure. + DK_CXLFLASH_VERIFY ------------------ This ioctl is used to detect various changes such as the capacity of diff --git a/drivers/scsi/cxlflash/superpipe.c b/drivers/scsi/cxlflash/superpipe.c index fe9f17a6268b..ad0f9968ccfb 100644 --- a/drivers/scsi/cxlflash/superpipe.c +++ b/drivers/scsi/cxlflash/superpipe.c @@ -56,6 +56,19 @@ static void marshal_det_to_rele(struct dk_cxlflash_detach *detach, release->context_id = detach->context_id; } +/** + * marshal_udir_to_rele() - translate udirect to release structure + * @udirect: Source structure from which to translate/copy. + * @release: Destination structure for the translate/copy. + */ +static void marshal_udir_to_rele(struct dk_cxlflash_udirect *udirect, + struct dk_cxlflash_release *release) +{ + release->hdr = udirect->hdr; + release->context_id = udirect->context_id; + release->rsrc_handle = udirect->rsrc_handle; +} + /** * cxlflash_free_errpage() - frees resources associated with global error page */ @@ -622,6 +635,7 @@ int _cxlflash_disk_release(struct scsi_device *sdev, res_hndl_t rhndl = release->rsrc_handle; int rc = 0; + int rcr = 0; u64 ctxid = DECODE_CTXID(release->context_id), rctxid = release->context_id; @@ -686,8 +700,12 @@ int _cxlflash_disk_release(struct scsi_device *sdev, rhte_f1->dw = 0; dma_wmb(); /* Make RHT entry bottom-half clearing visible */ - if (!ctxi->err_recovery_active) - cxlflash_afu_sync(afu, ctxid, rhndl, AFU_HW_SYNC); + if (!ctxi->err_recovery_active) { + rcr = cxlflash_afu_sync(afu, ctxid, rhndl, AFU_HW_SYNC); + if (unlikely(rcr)) + dev_dbg(dev, "%s: AFU sync failed rc=%d\n", + __func__, rcr); + } break; default: WARN(1, "Unsupported LUN mode!"); @@ -1929,6 +1947,7 @@ static int cxlflash_disk_direct_open(struct scsi_device *sdev, void *arg) struct afu *afu = cfg->afu; struct llun_info *lli = sdev->hostdata; struct glun_info *gli = lli->parent; + struct dk_cxlflash_release rel = { { 0 }, 0 }; struct dk_cxlflash_udirect *pphys = (struct dk_cxlflash_udirect *)arg; @@ -1970,13 +1989,18 @@ static int cxlflash_disk_direct_open(struct scsi_device *sdev, void *arg) rsrc_handle = (rhte - ctxi->rht_start); rht_format1(rhte, lli->lun_id[sdev->channel], ctxi->rht_perms, port); - cxlflash_afu_sync(afu, ctxid, rsrc_handle, AFU_LW_SYNC); last_lba = gli->max_lba; pphys->hdr.return_flags = 0; pphys->last_lba = last_lba; pphys->rsrc_handle = rsrc_handle; + rc = cxlflash_afu_sync(afu, ctxid, rsrc_handle, AFU_LW_SYNC); + if (unlikely(rc)) { + dev_dbg(dev, "%s: AFU sync failed rc=%d\n", __func__, rc); + goto err2; + } + out: if (likely(ctxi)) put_context(ctxi); @@ -1984,6 +2008,10 @@ out: __func__, rsrc_handle, rc, last_lba); return rc; +err2: + marshal_udir_to_rele(pphys, &rel); + _cxlflash_disk_release(sdev, ctxi, &rel); + goto out; err1: cxlflash_lun_detach(gli); goto out; diff --git a/drivers/scsi/cxlflash/vlun.c b/drivers/scsi/cxlflash/vlun.c index 90b5c19f81f0..0800bcba5a00 100644 --- a/drivers/scsi/cxlflash/vlun.c +++ b/drivers/scsi/cxlflash/vlun.c @@ -594,7 +594,9 @@ static int grow_lxt(struct afu *afu, rhte->lxt_cnt = my_new_size; dma_wmb(); /* Make RHT entry's LXT table size update visible */ - cxlflash_afu_sync(afu, ctxid, rhndl, AFU_LW_SYNC); + rc = cxlflash_afu_sync(afu, ctxid, rhndl, AFU_LW_SYNC); + if (unlikely(rc)) + rc = -EAGAIN; /* free old lxt if reallocated */ if (lxt != lxt_old) @@ -673,8 +675,11 @@ static int shrink_lxt(struct afu *afu, rhte->lxt_start = lxt; dma_wmb(); /* Make RHT entry's LXT table update visible */ - if (needs_sync) - cxlflash_afu_sync(afu, ctxid, rhndl, AFU_HW_SYNC); + if (needs_sync) { + rc = cxlflash_afu_sync(afu, ctxid, rhndl, AFU_HW_SYNC); + if (unlikely(rc)) + rc = -EAGAIN; + } if (needs_ws) { /* @@ -792,6 +797,21 @@ int _cxlflash_vlun_resize(struct scsi_device *sdev, rc = grow_lxt(afu, sdev, ctxid, rhndl, rhte, &new_size); else if (new_size < rhte->lxt_cnt) rc = shrink_lxt(afu, sdev, rhndl, rhte, ctxi, &new_size); + else { + /* + * Rare case where there is already sufficient space, just + * need to perform a translation sync with the AFU. This + * scenario likely follows a previous sync failure during + * a resize operation. Accordingly, perform the heavyweight + * form of translation sync as it is unknown which type of + * resize failed previously. + */ + rc = cxlflash_afu_sync(afu, ctxid, rhndl, AFU_HW_SYNC); + if (unlikely(rc)) { + rc = -EAGAIN; + goto out; + } + } resize->hdr.return_flags = 0; resize->last_lba = (new_size * MC_CHUNK_SIZE * gli->blk_len); @@ -1084,10 +1104,13 @@ static int clone_lxt(struct afu *afu, { struct cxlflash_cfg *cfg = afu->parent; struct device *dev = &cfg->dev->dev; - struct sisl_lxt_entry *lxt; + struct sisl_lxt_entry *lxt = NULL; + bool locked = false; u32 ngrps; u64 aun; /* chunk# allocated by block allocator */ - int i, j; + int j; + int i = 0; + int rc = 0; ngrps = LXT_NUM_GROUPS(rhte_src->lxt_cnt); @@ -1095,33 +1118,29 @@ static int clone_lxt(struct afu *afu, /* allocate new LXTs for clone */ lxt = kzalloc((sizeof(*lxt) * LXT_GROUP_SIZE * ngrps), GFP_KERNEL); - if (unlikely(!lxt)) - return -ENOMEM; + if (unlikely(!lxt)) { + rc = -ENOMEM; + goto out; + } /* copy over */ memcpy(lxt, rhte_src->lxt_start, (sizeof(*lxt) * rhte_src->lxt_cnt)); - /* clone the LBAs in block allocator via ref_cnt */ + /* clone the LBAs in block allocator via ref_cnt, note that the + * block allocator mutex must be held until it is established + * that this routine will complete without the need for a + * cleanup. + */ mutex_lock(&blka->mutex); + locked = true; for (i = 0; i < rhte_src->lxt_cnt; i++) { aun = (lxt[i].rlba_base >> MC_CHUNK_SHIFT); if (ba_clone(&blka->ba_lun, aun) == -1ULL) { - /* free the clones already made */ - for (j = 0; j < i; j++) { - aun = (lxt[j].rlba_base >> - MC_CHUNK_SHIFT); - ba_free(&blka->ba_lun, aun); - } - - mutex_unlock(&blka->mutex); - kfree(lxt); - return -EIO; + rc = -EIO; + goto err; } } - mutex_unlock(&blka->mutex); - } else { - lxt = NULL; } /* @@ -1136,10 +1155,31 @@ static int clone_lxt(struct afu *afu, rhte->lxt_cnt = rhte_src->lxt_cnt; dma_wmb(); /* Make RHT entry's LXT table size update visible */ - cxlflash_afu_sync(afu, ctxid, rhndl, AFU_LW_SYNC); + rc = cxlflash_afu_sync(afu, ctxid, rhndl, AFU_LW_SYNC); + if (unlikely(rc)) { + rc = -EAGAIN; + goto err2; + } - dev_dbg(dev, "%s: returning\n", __func__); - return 0; +out: + if (locked) + mutex_unlock(&blka->mutex); + dev_dbg(dev, "%s: returning rc=%d\n", __func__, rc); + return rc; +err2: + /* Reset the RHTE */ + rhte->lxt_cnt = 0; + dma_wmb(); + rhte->lxt_start = NULL; + dma_wmb(); +err: + /* free the clones already made */ + for (j = 0; j < i; j++) { + aun = (lxt[j].rlba_base >> MC_CHUNK_SHIFT); + ba_free(&blka->ba_lun, aun); + } + kfree(lxt); + goto out; } /**