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author | Uma Krishnan <ukrishn@linux.vnet.ibm.com> | 2017-06-22 05:14:30 +0300 |
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committer | Martin K. Petersen <martin.petersen@oracle.com> | 2017-06-26 22:01:08 +0300 |
commit | c2c292f45029a6850cd14c7c2fa4fc479b8f74aa (patch) | |
tree | e73b1f0e026dd547e426aa1f4019c5895ad85ade /drivers/scsi/cxlflash/vlun.c | |
parent | 0b09e711189952ff9d411593a8d74ec12a956c57 (diff) | |
download | linux-c2c292f45029a6850cd14c7c2fa4fc479b8f74aa.tar.xz |
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 <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/cxlflash/vlun.c')
-rw-r--r-- | drivers/scsi/cxlflash/vlun.c | 88 |
1 files changed, 64 insertions, 24 deletions
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; } /** |