diff mbox series

[v6,1/3] hw/block/nvme: add dulbe support

Message ID 20201026060101.371900-2-its@irrelevant.dk
State Superseded
Headers show
Series hw/block/nvme: dulbe and dsm support | expand

Commit Message

Klaus Jensen Oct. 26, 2020, 6 a.m. UTC
From: Klaus Jensen <k.jensen@samsung.com>

Add support for reporting the Deallocated or Unwritten Logical Block
Error (DULBE).

Rely on the block status flags reported by the block layer and consider
any block with the BDRV_BLOCK_ZERO flag to be deallocated.

Multiple factors affect when a Write Zeroes command result in
deallocation of blocks.

  * the underlying file system block size
  * the blockdev format
  * the 'discard' and 'logical_block_size' parameters

     format | discard | wz (512B)  wz (4KiB)  wz (64KiB)
    -----------------------------------------------------
      qcow2    ignore   n          n          y
      qcow2    unmap    n          n          y
      raw      ignore   n          y          y
      raw      unmap    n          y          y

So, this works best with an image in raw format and 4KiB LBAs, since
holes can then be punched on a per-block basis (this assumes a file
system with a 4kb block size, YMMV). A qcow2 image, uses a cluster size
of 64KiB by default and blocks will only be marked deallocated if a full
cluster is zeroed or discarded. However, this *is* consistent with the
spec since Write Zeroes "should" deallocate the block if the Deallocate
attribute is set and "may" deallocate if the Deallocate attribute is not
set. Thus, we always try to deallocate (the BDRV_REQ_MAY_UNMAP flag is
always set).

Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
---
 hw/block/nvme-ns.h    |  4 +++
 include/block/nvme.h  |  5 +++
 hw/block/nvme-ns.c    |  8 +++--
 hw/block/nvme.c       | 83 +++++++++++++++++++++++++++++++++++++++++--
 hw/block/trace-events |  4 +++
 5 files changed, 99 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/hw/block/nvme-ns.h b/hw/block/nvme-ns.h
index 83734f4606e1..44bf6271b744 100644
--- a/hw/block/nvme-ns.h
+++ b/hw/block/nvme-ns.h
@@ -31,6 +31,10 @@  typedef struct NvmeNamespace {
     NvmeIdNs     id_ns;
 
     NvmeNamespaceParams params;
+
+    struct {
+        uint32_t err_rec;
+    } features;
 } NvmeNamespace;
 
 static inline uint32_t nvme_nsid(NvmeNamespace *ns)
diff --git a/include/block/nvme.h b/include/block/nvme.h
index 8a46d9cf015f..966c3bb304bd 100644
--- a/include/block/nvme.h
+++ b/include/block/nvme.h
@@ -687,6 +687,7 @@  enum NvmeStatusCodes {
     NVME_E2E_REF_ERROR          = 0x0284,
     NVME_CMP_FAILURE            = 0x0285,
     NVME_ACCESS_DENIED          = 0x0286,
+    NVME_DULB                   = 0x0287,
     NVME_MORE                   = 0x2000,
     NVME_DNR                    = 0x4000,
     NVME_NO_COMPLETE            = 0xffff,
@@ -903,6 +904,9 @@  enum NvmeIdCtrlLpa {
 #define NVME_AEC_NS_ATTR(aec)       ((aec >> 8) & 0x1)
 #define NVME_AEC_FW_ACTIVATION(aec) ((aec >> 9) & 0x1)
 
+#define NVME_ERR_REC_TLER(err_rec)  (err_rec & 0xffff)
+#define NVME_ERR_REC_DULBE(err_rec) (err_rec & 0x10000)
+
 enum NvmeFeatureIds {
     NVME_ARBITRATION                = 0x1,
     NVME_POWER_MANAGEMENT           = 0x2,
@@ -1023,6 +1027,7 @@  enum NvmeNsIdentifierType {
 
 
 #define NVME_ID_NS_NSFEAT_THIN(nsfeat)      ((nsfeat & 0x1))
+#define NVME_ID_NS_NSFEAT_DULBE(nsfeat)     ((nsfeat >> 2) & 0x1)
 #define NVME_ID_NS_FLBAS_EXTENDED(flbas)    ((flbas >> 4) & 0x1)
 #define NVME_ID_NS_FLBAS_INDEX(flbas)       ((flbas & 0xf))
 #define NVME_ID_NS_MC_SEPARATE(mc)          ((mc >> 1) & 0x1)
diff --git a/hw/block/nvme-ns.c b/hw/block/nvme-ns.c
index 31c80cdf5b5f..f1cc734c60f5 100644
--- a/hw/block/nvme-ns.c
+++ b/hw/block/nvme-ns.c
@@ -33,9 +33,7 @@  static void nvme_ns_init(NvmeNamespace *ns)
     NvmeIdNs *id_ns = &ns->id_ns;
     int lba_index = NVME_ID_NS_FLBAS_INDEX(ns->id_ns.flbas);
 
-    if (blk_get_flags(ns->blkconf.blk) & BDRV_O_UNMAP) {
-        ns->id_ns.dlfeat = 0x9;
-    }
+    ns->id_ns.dlfeat = 0x9;
 
     id_ns->lbaf[lba_index].ds = 31 - clz32(ns->blkconf.logical_block_size);
 
@@ -44,6 +42,9 @@  static void nvme_ns_init(NvmeNamespace *ns)
     /* no thin provisioning */
     id_ns->ncap = id_ns->nsze;
     id_ns->nuse = id_ns->ncap;
+
+    /* support DULBE */
+    id_ns->nsfeat |= 0x4;
 }
 
 static int nvme_ns_init_blk(NvmeCtrl *n, NvmeNamespace *ns, Error **errp)
@@ -92,6 +93,7 @@  int nvme_ns_setup(NvmeCtrl *n, NvmeNamespace *ns, Error **errp)
     }
 
     nvme_ns_init(ns);
+
     if (nvme_register_namespace(n, ns, errp)) {
         return -1;
     }
diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index fa2cba744b57..4ab0705f5a92 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -105,6 +105,7 @@  static const bool nvme_feature_support[NVME_FID_MAX] = {
 
 static const uint32_t nvme_feature_cap[NVME_FID_MAX] = {
     [NVME_TEMPERATURE_THRESHOLD]    = NVME_FEAT_CAP_CHANGE,
+    [NVME_ERROR_RECOVERY]           = NVME_FEAT_CAP_CHANGE | NVME_FEAT_CAP_NS,
     [NVME_VOLATILE_WRITE_CACHE]     = NVME_FEAT_CAP_CHANGE,
     [NVME_NUMBER_OF_QUEUES]         = NVME_FEAT_CAP_CHANGE,
     [NVME_ASYNCHRONOUS_EVENT_CONF]  = NVME_FEAT_CAP_CHANGE,
@@ -878,6 +879,41 @@  static inline uint16_t nvme_check_bounds(NvmeCtrl *n, NvmeNamespace *ns,
     return NVME_SUCCESS;
 }
 
+static uint16_t nvme_check_dulbe(NvmeNamespace *ns, uint64_t slba,
+                                 uint32_t nlb)
+{
+    BlockDriverState *bs = blk_bs(ns->blkconf.blk);
+
+    int64_t pnum = 0, bytes = nvme_l2b(ns, nlb);
+    int64_t offset = nvme_l2b(ns, slba);
+    bool zeroed;
+    int ret;
+
+    /*
+     * `pnum` holds the number of bytes after offset that shares the same
+     * allocation status as the byte at offset. If `pnum` is different from
+     * `bytes`, we should check the allocation status of the next range and
+     * continue this until all bytes have been checked.
+     */
+    do {
+        bytes -= pnum;
+
+        ret = bdrv_block_status(bs, offset, bytes, &pnum, NULL, NULL);
+
+        zeroed = !!(ret & BDRV_BLOCK_ZERO);
+
+        trace_pci_nvme_block_status(offset, bytes, pnum, ret, zeroed);
+
+        if (zeroed) {
+            return NVME_DULB;
+        }
+
+        offset += pnum;
+    } while (pnum != bytes);
+
+    return NVME_SUCCESS;
+}
+
 static void nvme_rw_cb(void *opaque, int ret)
 {
     NvmeRequest *req = opaque;
@@ -985,6 +1021,15 @@  static uint16_t nvme_rw(NvmeCtrl *n, NvmeRequest *req)
         goto invalid;
     }
 
+    if (acct == BLOCK_ACCT_READ) {
+        if (NVME_ERR_REC_DULBE(ns->features.err_rec)) {
+            status = nvme_check_dulbe(ns, slba, nlb);
+            if (status) {
+                goto invalid;
+            }
+        }
+    }
+
     status = nvme_map_dptr(n, data_size, req);
     if (status) {
         goto invalid;
@@ -1632,6 +1677,7 @@  static uint16_t nvme_get_feature(NvmeCtrl *n, NvmeRequest *req)
     uint8_t fid = NVME_GETSETFEAT_FID(dw10);
     NvmeGetFeatureSelect sel = NVME_GETFEAT_SELECT(dw10);
     uint16_t iv;
+    NvmeNamespace *ns;
 
     static const uint32_t nvme_feature_default[NVME_FID_MAX] = {
         [NVME_ARBITRATION] = NVME_ARB_AB_NOLIMIT,
@@ -1694,6 +1740,18 @@  static uint16_t nvme_get_feature(NvmeCtrl *n, NvmeRequest *req)
         }
 
         return NVME_INVALID_FIELD | NVME_DNR;
+    case NVME_ERROR_RECOVERY:
+        if (!nvme_nsid_valid(n, nsid)) {
+            return NVME_INVALID_NSID | NVME_DNR;
+        }
+
+        ns = nvme_ns(n, nsid);
+        if (unlikely(!ns)) {
+            return NVME_INVALID_FIELD | NVME_DNR;
+        }
+
+        result = ns->features.err_rec;
+        goto out;
     case NVME_VOLATILE_WRITE_CACHE:
         result = n->features.vwc;
         trace_pci_nvme_getfeat_vwcache(result ? "enabled" : "disabled");
@@ -1766,7 +1824,7 @@  static uint16_t nvme_set_feature_timestamp(NvmeCtrl *n, NvmeRequest *req)
 
 static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeRequest *req)
 {
-    NvmeNamespace *ns;
+    NvmeNamespace *ns = NULL;
 
     NvmeCmd *cmd = &req->cmd;
     uint32_t dw10 = le32_to_cpu(cmd->cdw10);
@@ -1774,6 +1832,7 @@  static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeRequest *req)
     uint32_t nsid = le32_to_cpu(cmd->nsid);
     uint8_t fid = NVME_GETSETFEAT_FID(dw10);
     uint8_t save = NVME_SETFEAT_SAVE(dw10);
+    int i;
 
     trace_pci_nvme_setfeat(nvme_cid(req), nsid, fid, save, dw11);
 
@@ -1833,11 +1892,31 @@  static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeRequest *req)
                                NVME_LOG_SMART_INFO);
         }
 
+        break;
+    case NVME_ERROR_RECOVERY:
+        if (nsid == NVME_NSID_BROADCAST) {
+            for (i = 1; i <= n->num_namespaces; i++) {
+                ns = nvme_ns(n, i);
+
+                if (!ns) {
+                    continue;
+                }
+
+                if (NVME_ID_NS_NSFEAT_DULBE(ns->id_ns.nsfeat)) {
+                    ns->features.err_rec = dw11;
+                }
+            }
+
+            break;
+        }
+
+        assert(ns);
+        ns->features.err_rec = dw11;
         break;
     case NVME_VOLATILE_WRITE_CACHE:
         n->features.vwc = dw11 & 0x1;
 
-        for (int i = 1; i <= n->num_namespaces; i++) {
+        for (i = 1; i <= n->num_namespaces; i++) {
             ns = nvme_ns(n, i);
             if (!ns) {
                 continue;
diff --git a/hw/block/trace-events b/hw/block/trace-events
index c1537e3ac0b0..1ffe0b3f76b5 100644
--- a/hw/block/trace-events
+++ b/hw/block/trace-events
@@ -43,6 +43,10 @@  pci_nvme_admin_cmd(uint16_t cid, uint16_t sqid, uint8_t opcode, const char *opna
 pci_nvme_rw(uint16_t cid, const char *verb, uint32_t nsid, uint32_t nlb, uint64_t count, uint64_t lba) "cid %"PRIu16" opname '%s' nsid %"PRIu32" nlb %"PRIu32" count %"PRIu64" lba 0x%"PRIx64""
 pci_nvme_rw_cb(uint16_t cid, const char *blkname) "cid %"PRIu16" blk '%s'"
 pci_nvme_write_zeroes(uint16_t cid, uint32_t nsid, uint64_t slba, uint32_t nlb) "cid %"PRIu16" nsid %"PRIu32" slba %"PRIu64" nlb %"PRIu32""
+pci_nvme_block_status(int64_t offset, int64_t bytes, int64_t pnum, int ret, bool zeroed) "offset %"PRId64" bytes %"PRId64" pnum %"PRId64" ret 0x%x zeroed %d"
+pci_nvme_dsm(uint16_t cid, uint32_t nsid, uint32_t nr, uint32_t attr) "cid %"PRIu16" nsid %"PRIu32" nr %"PRIu32" attr 0x%"PRIx32""
+pci_nvme_dsm_deallocate(uint16_t cid, uint32_t nsid, uint64_t slba, uint32_t nlb) "cid %"PRIu16" nsid %"PRIu32" slba %"PRIu64" nlb %"PRIu32""
+pci_nvme_aio_discard_cb(uint16_t cid) "cid %"PRIu16""
 pci_nvme_create_sq(uint64_t addr, uint16_t sqid, uint16_t cqid, uint16_t qsize, uint16_t qflags) "create submission queue, addr=0x%"PRIx64", sqid=%"PRIu16", cqid=%"PRIu16", qsize=%"PRIu16", qflags=%"PRIu16""
 pci_nvme_create_cq(uint64_t addr, uint16_t cqid, uint16_t vector, uint16_t size, uint16_t qflags, int ien) "create completion queue, addr=0x%"PRIx64", cqid=%"PRIu16", vector=%"PRIu16", qsize=%"PRIu16", qflags=%"PRIu16", ien=%d"
 pci_nvme_del_sq(uint16_t qid) "deleting submission queue sqid=%"PRIu16""