Merge remote-tracking branch 'stefanha/block' into staging

# By Kevin Wolf (22) and Fam Zheng (1)
# Via Stefan Hajnoczi
* stefanha/block: (23 commits)
  vmdk: refuse to open higher version than supported
  block: Always enable discard on the protocol level
  qcow2: Batch discards
  qcow2: Options to enable discard for freed clusters
  qcow2: Add refcount update reason to all callers
  Revert "block: Disable driver-specific options for 1.5"
  ide: Clean up ide_exec_cmd()
  ide: Convert SMART commands to ide_cmd_table handler
  ide: Convert CF-ATA commands to ide_cmd_table handler
  ide: Convert ATAPI commands to ide_cmd_table handler
  ide: Convert SEEK to ide_cmd_table handler
  ide: Convert FLUSH CACHE to ide_cmd_table handler
  ide: Convert SET FEATURES to ide_cmd_table handler
  ide: Convert CHECK POWER MDOE to ide_cmd_table handler
  ide: Convert READ NATIVE MAX ADDRESS to ide_cmd_table handler
  ide: Convert DMA read/write commands to ide_cmd_table handler
  ide: Convert PIO read/write commands to ide_cmd_table handler
  ide: Convert read/write multiple commands to ide_cmd_table handler
  ide: Convert verify commands to ide_cmd_table handler
  ide: Convert cmd_nop commands to ide_cmd_table handler
  ...

Message-id: 1372065035-19601-1-git-send-email-stefanha@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

block.c

@@ -1045,7 +1045,7 @@ int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options,
     extract_subqdict(options, &file_options, "file.");
 
     ret = bdrv_file_open(&file, filename, file_options,
-                         bdrv_open_flags(bs, flags));
+                         bdrv_open_flags(bs, flags | BDRV_O_UNMAP));
     if (ret < 0) {
         goto fail;
     }

block/qcow2-cluster.c

@@ -98,14 +98,16 @@ int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
         goto fail;
     }
     g_free(s->l1_table);
-    qcow2_free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t));
+    qcow2_free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t),
+                        QCOW2_DISCARD_OTHER);
     s->l1_table_offset = new_l1_table_offset;
     s->l1_table = new_l1_table;
     s->l1_size = new_l1_size;
     return 0;
  fail:
     g_free(new_l1_table);
-    qcow2_free_clusters(bs, new_l1_table_offset, new_l1_size2);
+    qcow2_free_clusters(bs, new_l1_table_offset, new_l1_size2,
+                        QCOW2_DISCARD_OTHER);
     return ret;
 }
 
@@ -548,7 +550,8 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
 
         /* Then decrease the refcount of the old table */
         if (l2_offset) {
-            qcow2_free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
+            qcow2_free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t),
+                                QCOW2_DISCARD_OTHER);
         }
     }
 
@@ -715,10 +718,14 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m)
     /*
      * If this was a COW, we need to decrease the refcount of the old cluster.
      * Also flush bs->file to get the right order for L2 and refcount update.
+     *
+     * Don't discard clusters that reach a refcount of 0 (e.g. compressed
+     * clusters), the next write will reuse them anyway.
      */
     if (j != 0) {
         for (i = 0; i < j; i++) {
-            qcow2_free_any_clusters(bs, be64_to_cpu(old_cluster[i]), 1);
+            qcow2_free_any_clusters(bs, be64_to_cpu(old_cluster[i]), 1,
+                                    QCOW2_DISCARD_NEVER);
         }
     }
 
@@ -1339,7 +1346,7 @@ static int discard_single_l2(BlockDriverState *bs, uint64_t offset,
         l2_table[l2_index + i] = cpu_to_be64(0);
 
         /* Then decrease the refcount */
-        qcow2_free_any_clusters(bs, old_offset, 1);
+        qcow2_free_any_clusters(bs, old_offset, 1, QCOW2_DISCARD_REQUEST);
     }
 
     ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
@@ -1370,18 +1377,25 @@ int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset,
 
     nb_clusters = size_to_clusters(s, end_offset - offset);
 
+    s->cache_discards = true;
+
     /* Each L2 table is handled by its own loop iteration */
     while (nb_clusters > 0) {
         ret = discard_single_l2(bs, offset, nb_clusters);
         if (ret < 0) {
-            return ret;
+            goto fail;
         }
 
         nb_clusters -= ret;
         offset += (ret * s->cluster_size);
     }
 
-    return 0;
+    ret = 0;
+fail:
+    s->cache_discards = false;
+    qcow2_process_discards(bs, ret);
+
+    return ret;
 }
 
 /*
@@ -1415,7 +1429,7 @@ static int zero_single_l2(BlockDriverState *bs, uint64_t offset,
         qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
         if (old_offset & QCOW_OFLAG_COMPRESSED) {
             l2_table[l2_index + i] = cpu_to_be64(QCOW_OFLAG_ZERO);
-            qcow2_free_any_clusters(bs, old_offset, 1);
+            qcow2_free_any_clusters(bs, old_offset, 1, QCOW2_DISCARD_REQUEST);
         } else {
             l2_table[l2_index + i] |= cpu_to_be64(QCOW_OFLAG_ZERO);
         }
@@ -1443,15 +1457,22 @@ int qcow2_zero_clusters(BlockDriverState *bs, uint64_t offset, int nb_sectors)
     /* Each L2 table is handled by its own loop iteration */
     nb_clusters = size_to_clusters(s, nb_sectors << BDRV_SECTOR_BITS);
 
+    s->cache_discards = true;
+
     while (nb_clusters > 0) {
         ret = zero_single_l2(bs, offset, nb_clusters);
         if (ret < 0) {
-            return ret;
+            goto fail;
         }
 
         nb_clusters -= ret;
         offset += (ret * s->cluster_size);
     }
 
-    return 0;
+    ret = 0;
+fail:
+    s->cache_discards = false;
+    qcow2_process_discards(bs, ret);
+
+    return ret;
 }

block/qcow2-refcount.c

@@ -29,7 +29,7 @@
 static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size);
 static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs,
                             int64_t offset, int64_t length,
-                            int addend);
+                            int addend, enum qcow2_discard_type type);
 
 
 /*********************************************************/
@@ -235,7 +235,8 @@ static int alloc_refcount_block(BlockDriverState *bs,
     } else {
         /* Described somewhere else. This can recurse at most twice before we
          * arrive at a block that describes itself. */
-        ret = update_refcount(bs, new_block, s->cluster_size, 1);
+        ret = update_refcount(bs, new_block, s->cluster_size, 1,
+                              QCOW2_DISCARD_NEVER);
         if (ret < 0) {
             goto fail_block;
         }
@@ -399,7 +400,8 @@ static int alloc_refcount_block(BlockDriverState *bs,
 
     /* Free old table. Remember, we must not change free_cluster_index */
     uint64_t old_free_cluster_index = s->free_cluster_index;
-    qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t));
+    qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t),
+                        QCOW2_DISCARD_OTHER);
     s->free_cluster_index = old_free_cluster_index;
 
     ret = load_refcount_block(bs, new_block, (void**) refcount_block);
@@ -418,9 +420,77 @@ fail_block:
     return ret;
 }
 
+void qcow2_process_discards(BlockDriverState *bs, int ret)
+{
+    BDRVQcowState *s = bs->opaque;
+    Qcow2DiscardRegion *d, *next;
+
+    QTAILQ_FOREACH_SAFE(d, &s->discards, next, next) {
+        QTAILQ_REMOVE(&s->discards, d, next);
+
+        /* Discard is optional, ignore the return value */
+        if (ret >= 0) {
+            bdrv_discard(bs->file,
+                         d->offset >> BDRV_SECTOR_BITS,
+                         d->bytes >> BDRV_SECTOR_BITS);
+        }
+
+        g_free(d);
+    }
+}
+
+static void update_refcount_discard(BlockDriverState *bs,
+                                    uint64_t offset, uint64_t length)
+{
+    BDRVQcowState *s = bs->opaque;
+    Qcow2DiscardRegion *d, *p, *next;
+
+    QTAILQ_FOREACH(d, &s->discards, next) {
+        uint64_t new_start = MIN(offset, d->offset);
+        uint64_t new_end = MAX(offset + length, d->offset + d->bytes);
+
+        if (new_end - new_start <= length + d->bytes) {
+            /* There can't be any overlap, areas ending up here have no
+             * references any more and therefore shouldn't get freed another
+             * time. */
+            assert(d->bytes + length == new_end - new_start);
+            d->offset = new_start;
+            d->bytes = new_end - new_start;
+            goto found;
+        }
+    }
+
+    d = g_malloc(sizeof(*d));
+    *d = (Qcow2DiscardRegion) {
+        .bs     = bs,
+        .offset = offset,
+        .bytes  = length,
+    };
+    QTAILQ_INSERT_TAIL(&s->discards, d, next);
+
+found:
+    /* Merge discard requests if they are adjacent now */
+    QTAILQ_FOREACH_SAFE(p, &s->discards, next, next) {
+        if (p == d
+            || p->offset > d->offset + d->bytes
+            || d->offset > p->offset + p->bytes)
+        {
+            continue;
+        }
+
+        /* Still no overlap possible */
+        assert(p->offset == d->offset + d->bytes
+            || d->offset == p->offset + p->bytes);
+
+        QTAILQ_REMOVE(&s->discards, p, next);
+        d->offset = MIN(d->offset, p->offset);
+        d->bytes += p->bytes;
+    }
+}
+
 /* XXX: cache several refcount block clusters ? */
 static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs,
-    int64_t offset, int64_t length, int addend)
+    int64_t offset, int64_t length, int addend, enum qcow2_discard_type type)
 {
     BDRVQcowState *s = bs->opaque;
     int64_t start, last, cluster_offset;
@@ -486,10 +556,18 @@ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs,
             s->free_cluster_index = cluster_index;
         }
         refcount_block[block_index] = cpu_to_be16(refcount);
+
+        if (refcount == 0 && s->discard_passthrough[type]) {
+            update_refcount_discard(bs, cluster_offset, s->cluster_size);
+        }
     }
 
     ret = 0;
 fail:
+    if (!s->cache_discards) {
+        qcow2_process_discards(bs, ret);
+    }
+
     /* Write last changed block to disk */
     if (refcount_block) {
         int wret;
@@ -506,7 +584,8 @@ fail:
      */
     if (ret < 0) {
         int dummy;
-        dummy = update_refcount(bs, offset, cluster_offset - offset, -addend);
+        dummy = update_refcount(bs, offset, cluster_offset - offset, -addend,
+                                QCOW2_DISCARD_NEVER);
         (void)dummy;
     }
 
@@ -522,12 +601,14 @@ fail:
  */
 static int update_cluster_refcount(BlockDriverState *bs,
                                    int64_t cluster_index,
-                                   int addend)
+                                   int addend,
+                                   enum qcow2_discard_type type)
 {
     BDRVQcowState *s = bs->opaque;
     int ret;
 
-    ret = update_refcount(bs, cluster_index << s->cluster_bits, 1, addend);
+    ret = update_refcount(bs, cluster_index << s->cluster_bits, 1, addend,
+                          type);
     if (ret < 0) {
         return ret;
     }
@@ -579,7 +660,7 @@ int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size)
         return offset;
     }
 
-    ret = update_refcount(bs, offset, size, 1);
+    ret = update_refcount(bs, offset, size, 1, QCOW2_DISCARD_NEVER);
     if (ret < 0) {
         return ret;
     }
@@ -611,7 +692,8 @@ int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
     old_free_cluster_index = s->free_cluster_index;
     s->free_cluster_index = cluster_index + i;
 
-    ret = update_refcount(bs, offset, i << s->cluster_bits, 1);
+    ret = update_refcount(bs, offset, i << s->cluster_bits, 1,
+                          QCOW2_DISCARD_NEVER);
     if (ret < 0) {
         return ret;
     }
@@ -649,7 +731,8 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
         if (free_in_cluster == 0)
             s->free_byte_offset = 0;
         if ((offset & (s->cluster_size - 1)) != 0)
-            update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
+            update_cluster_refcount(bs, offset >> s->cluster_bits, 1,
+                                    QCOW2_DISCARD_NEVER);
     } else {
         offset = qcow2_alloc_clusters(bs, s->cluster_size);
         if (offset < 0) {
@@ -659,7 +742,8 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
         if ((cluster_offset + s->cluster_size) == offset) {
             /* we are lucky: contiguous data */
             offset = s->free_byte_offset;
-            update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
+            update_cluster_refcount(bs, offset >> s->cluster_bits, 1,
+                                    QCOW2_DISCARD_NEVER);
             s->free_byte_offset += size;
         } else {
             s->free_byte_offset = offset;
@@ -676,12 +760,13 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
 }
 
 void qcow2_free_clusters(BlockDriverState *bs,
-                          int64_t offset, int64_t size)
+                          int64_t offset, int64_t size,
+                          enum qcow2_discard_type type)
 {
     int ret;
 
     BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_FREE);
-    ret = update_refcount(bs, offset, size, -1);
+    ret = update_refcount(bs, offset, size, -1, type);
     if (ret < 0) {
         fprintf(stderr, "qcow2_free_clusters failed: %s\n", strerror(-ret));
         /* TODO Remember the clusters to free them later and avoid leaking */
@@ -692,8 +777,8 @@ void qcow2_free_clusters(BlockDriverState *bs,
  * Free a cluster using its L2 entry (handles clusters of all types, e.g.
  * normal cluster, compressed cluster, etc.)
  */
-void qcow2_free_any_clusters(BlockDriverState *bs,
-    uint64_t l2_entry, int nb_clusters)
+void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
+                             int nb_clusters, enum qcow2_discard_type type)
 {
     BDRVQcowState *s = bs->opaque;
 
@@ -705,12 +790,12 @@ void qcow2_free_any_clusters(BlockDriverState *bs,
                            s->csize_mask) + 1;
             qcow2_free_clusters(bs,
                 (l2_entry & s->cluster_offset_mask) & ~511,
-                nb_csectors * 512);
+                nb_csectors * 512, type);
         }
         break;
     case QCOW2_CLUSTER_NORMAL:
         qcow2_free_clusters(bs, l2_entry & L2E_OFFSET_MASK,
-                            nb_clusters << s->cluster_bits);
+                            nb_clusters << s->cluster_bits, type);
         break;
     case QCOW2_CLUSTER_UNALLOCATED:
     case QCOW2_CLUSTER_ZERO:
@@ -741,6 +826,8 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
     l1_table = NULL;
     l1_size2 = l1_size * sizeof(uint64_t);
 
+    s->cache_discards = true;
+
     /* WARNING: qcow2_snapshot_goto relies on this function not using the
      * l1_table_offset when it is the current s->l1_table_offset! Be careful
      * when changing this! */
@@ -785,7 +872,8 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
                             int ret;
                             ret = update_refcount(bs,
                                 (offset & s->cluster_offset_mask) & ~511,
-                                nb_csectors * 512, addend);
+                                nb_csectors * 512, addend,
+                                QCOW2_DISCARD_SNAPSHOT);
                             if (ret < 0) {
                                 goto fail;
                             }
@@ -795,7 +883,8 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
                     } else {
                         uint64_t cluster_index = (offset & L2E_OFFSET_MASK) >> s->cluster_bits;
                         if (addend != 0) {
-                            refcount = update_cluster_refcount(bs, cluster_index, addend);
+                            refcount = update_cluster_refcount(bs, cluster_index, addend,
+                                                               QCOW2_DISCARD_SNAPSHOT);
                         } else {
                             refcount = get_refcount(bs, cluster_index);
                         }
@@ -827,7 +916,8 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
 
 
             if (addend != 0) {
-                refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend);
+                refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend,
+                                                   QCOW2_DISCARD_SNAPSHOT);
             } else {
                 refcount = get_refcount(bs, l2_offset >> s->cluster_bits);
             }
@@ -850,6 +940,9 @@ fail:
         qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
     }
 
+    s->cache_discards = false;
+    qcow2_process_discards(bs, ret);
+
     /* Update L1 only if it isn't deleted anyway (addend = -1) */
     if (ret == 0 && addend >= 0 && l1_modified) {
         for (i = 0; i < l1_size; i++) {
@@ -1253,7 +1346,8 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
 
             if (num_fixed) {
                 ret = update_refcount(bs, i << s->cluster_bits, 1,
-                                      refcount2 - refcount1);
+                                      refcount2 - refcount1,
+                                      QCOW2_DISCARD_ALWAYS);
                 if (ret >= 0) {
                     (*num_fixed)++;
                     continue;

block/qcow2-snapshot.c

@@ -262,7 +262,8 @@ static int qcow2_write_snapshots(BlockDriverState *bs)
     }
 
     /* free the old snapshot table */
-    qcow2_free_clusters(bs, s->snapshots_offset, s->snapshots_size);
+    qcow2_free_clusters(bs, s->snapshots_offset, s->snapshots_size,
+                        QCOW2_DISCARD_SNAPSHOT);
     s->snapshots_offset = snapshots_offset;
     s->snapshots_size = snapshots_size;
     return 0;
@@ -569,7 +570,8 @@ int qcow2_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
     if (ret < 0) {
         return ret;
     }
-    qcow2_free_clusters(bs, sn.l1_table_offset, sn.l1_size * sizeof(uint64_t));
+    qcow2_free_clusters(bs, sn.l1_table_offset, sn.l1_size * sizeof(uint64_t),
+                        QCOW2_DISCARD_SNAPSHOT);
 
     /* must update the copied flag on the current cluster offsets */
     ret = qcow2_update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0);

block/qcow2.c

@@ -295,6 +295,22 @@ static QemuOptsList qcow2_runtime_opts = {
             .type = QEMU_OPT_BOOL,
             .help = "Postpone refcount updates",
         },
+        {
+            .name = QCOW2_OPT_DISCARD_REQUEST,
+            .type = QEMU_OPT_BOOL,
+            .help = "Pass guest discard requests to the layer below",
+        },
+        {
+            .name = QCOW2_OPT_DISCARD_SNAPSHOT,
+            .type = QEMU_OPT_BOOL,
+            .help = "Generate discard requests when snapshot related space "
+                    "is freed",
+        },
+        {
+            .name = QCOW2_OPT_DISCARD_OTHER,
+            .type = QEMU_OPT_BOOL,
+            .help = "Generate discard requests when other clusters are freed",
+        },
         { /* end of list */ }
     },
 };
@@ -470,6 +486,7 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags)
     }
 
     QLIST_INIT(&s->cluster_allocs);
+    QTAILQ_INIT(&s->discards);
 
     /* read qcow2 extensions */
     if (qcow2_read_extensions(bs, header.header_length, ext_end, NULL)) {
@@ -532,6 +549,16 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags)
     s->use_lazy_refcounts = qemu_opt_get_bool(opts, QCOW2_OPT_LAZY_REFCOUNTS,
         (s->compatible_features & QCOW2_COMPAT_LAZY_REFCOUNTS));
 
+    s->discard_passthrough[QCOW2_DISCARD_NEVER] = false;
+    s->discard_passthrough[QCOW2_DISCARD_ALWAYS] = true;
+    s->discard_passthrough[QCOW2_DISCARD_REQUEST] =
+        qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_REQUEST,
+                          flags & BDRV_O_UNMAP);
+    s->discard_passthrough[QCOW2_DISCARD_SNAPSHOT] =
+        qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_SNAPSHOT, true);
+    s->discard_passthrough[QCOW2_DISCARD_OTHER] =
+        qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_OTHER, false);
+
     qemu_opts_del(opts);
 
     if (s->use_lazy_refcounts && s->qcow_version < 3) {
@@ -1196,7 +1223,8 @@ static int preallocate(BlockDriverState *bs)
 
         ret = qcow2_alloc_cluster_link_l2(bs, meta);
         if (ret < 0) {
-            qcow2_free_any_clusters(bs, meta->alloc_offset, meta->nb_clusters);
+            qcow2_free_any_clusters(bs, meta->alloc_offset, meta->nb_clusters,
+                                    QCOW2_DISCARD_NEVER);
             return ret;
         }
 

block/qcow2.h

@@ -60,6 +60,9 @@
 
 
 #define QCOW2_OPT_LAZY_REFCOUNTS "lazy_refcounts"
+#define QCOW2_OPT_DISCARD_REQUEST "pass_discard_request"
+#define QCOW2_OPT_DISCARD_SNAPSHOT "pass_discard_snapshot"
+#define QCOW2_OPT_DISCARD_OTHER "pass_discard_other"
 
 typedef struct QCowHeader {
     uint32_t magic;
@@ -129,12 +132,28 @@ enum {
     QCOW2_COMPAT_FEAT_MASK            = QCOW2_COMPAT_LAZY_REFCOUNTS,
 };
 
+enum qcow2_discard_type {
+    QCOW2_DISCARD_NEVER = 0,
+    QCOW2_DISCARD_ALWAYS,
+    QCOW2_DISCARD_REQUEST,
+    QCOW2_DISCARD_SNAPSHOT,
+    QCOW2_DISCARD_OTHER,
+    QCOW2_DISCARD_MAX
+};
+
 typedef struct Qcow2Feature {
     uint8_t type;
     uint8_t bit;
     char    name[46];
 } QEMU_PACKED Qcow2Feature;
 
+typedef struct Qcow2DiscardRegion {
+    BlockDriverState *bs;
+    uint64_t offset;
+    uint64_t bytes;
+    QTAILQ_ENTRY(Qcow2DiscardRegion) next;
+} Qcow2DiscardRegion;
+
 typedef struct BDRVQcowState {
     int cluster_bits;
     int cluster_size;
@@ -178,6 +197,8 @@ typedef struct BDRVQcowState {
     int qcow_version;
     bool use_lazy_refcounts;
 
+    bool discard_passthrough[QCOW2_DISCARD_MAX];
+
     uint64_t incompatible_features;
     uint64_t compatible_features;
     uint64_t autoclear_features;
@@ -185,6 +206,8 @@ typedef struct BDRVQcowState {
     size_t unknown_header_fields_size;
     void* unknown_header_fields;
     QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
+    QTAILQ_HEAD (, Qcow2DiscardRegion) discards;
+    bool cache_discards;
 } BDRVQcowState;
 
 /* XXX: use std qcow open function ? */
@@ -349,9 +372,10 @@ int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
     int nb_clusters);
 int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
 void qcow2_free_clusters(BlockDriverState *bs,
-    int64_t offset, int64_t size);
-void qcow2_free_any_clusters(BlockDriverState *bs,
-    uint64_t cluster_offset, int nb_clusters);
+                          int64_t offset, int64_t size,
+                          enum qcow2_discard_type type);
+void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
+                             int nb_clusters, enum qcow2_discard_type type);
 
 int qcow2_update_snapshot_refcount(BlockDriverState *bs,
     int64_t l1_table_offset, int l1_size, int addend);
@@ -359,6 +383,8 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
 int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
                           BdrvCheckMode fix);
 
+void qcow2_process_discards(BlockDriverState *bs, int ret);
+
 /* qcow2-cluster.c functions */
 int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
                         bool exact_size);

block/vmdk.c

@@ -561,6 +561,15 @@ static int vmdk_open_vmdk4(BlockDriverState *bs,
         header = footer.header;
     }
 
+    if (le32_to_cpu(header.version) >= 3) {
+        char buf[64];
+        snprintf(buf, sizeof(buf), "VMDK version %d",
+                 le32_to_cpu(header.version));
+        qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
+                bs->device_name, "vmdk", buf);
+        return -ENOTSUP;
+    }
+
     l1_entry_sectors = le32_to_cpu(header.num_gtes_per_gte)
                         * le64_to_cpu(header.granularity);
     if (l1_entry_sectors == 0) {

blockdev.c

@@ -1737,120 +1737,10 @@ QemuOptsList qemu_drive_opts = {
     .name = "drive",
     .head = QTAILQ_HEAD_INITIALIZER(qemu_drive_opts.head),
     .desc = {
-        {
-            .name = "bus",
-            .type = QEMU_OPT_NUMBER,
-            .help = "bus number",
-        },{
-            .name = "unit",
-            .type = QEMU_OPT_NUMBER,
-            .help = "unit number (i.e. lun for scsi)",
-        },{
-            .name = "if",
-            .type = QEMU_OPT_STRING,
-            .help = "interface (ide, scsi, sd, mtd, floppy, pflash, virtio)",
-        },{
-            .name = "index",
-            .type = QEMU_OPT_NUMBER,
-            .help = "index number",
-        },{
-            .name = "cyls",
-            .type = QEMU_OPT_NUMBER,
-            .help = "number of cylinders (ide disk geometry)",
-        },{
-            .name = "heads",
-            .type = QEMU_OPT_NUMBER,
-            .help = "number of heads (ide disk geometry)",
-        },{
-            .name = "secs",
-            .type = QEMU_OPT_NUMBER,
-            .help = "number of sectors (ide disk geometry)",
-        },{
-            .name = "trans",
-            .type = QEMU_OPT_STRING,
-            .help = "chs translation (auto, lba. none)",
-        },{
-            .name = "media",
-            .type = QEMU_OPT_STRING,
-            .help = "media type (disk, cdrom)",
-        },{
-            .name = "snapshot",
-            .type = QEMU_OPT_BOOL,
-            .help = "enable/disable snapshot mode",
-        },{
-            .name = "file",
-            .type = QEMU_OPT_STRING,
-            .help = "disk image",
-        },{
-            .name = "discard",
-            .type = QEMU_OPT_STRING,
-            .help = "discard operation (ignore/off, unmap/on)",
-        },{
-            .name = "cache",
-            .type = QEMU_OPT_STRING,
-            .help = "host cache usage (none, writeback, writethrough, "
-                    "directsync, unsafe)",
-        },{
-            .name = "aio",
-            .type = QEMU_OPT_STRING,
-            .help = "host AIO implementation (threads, native)",
-        },{
-            .name = "format",
-            .type = QEMU_OPT_STRING,
-            .help = "disk format (raw, qcow2, ...)",
-        },{
-            .name = "serial",
-            .type = QEMU_OPT_STRING,
-            .help = "disk serial number",
-        },{
-            .name = "rerror",
-            .type = QEMU_OPT_STRING,
-            .help = "read error action",
-        },{
-            .name = "werror",
-            .type = QEMU_OPT_STRING,
-            .help = "write error action",
-        },{
-            .name = "addr",
-            .type = QEMU_OPT_STRING,
-            .help = "pci address (virtio only)",
-        },{
-            .name = "readonly",
-            .type = QEMU_OPT_BOOL,
-            .help = "open drive file as read-only",
-        },{
-            .name = "iops",
-            .type = QEMU_OPT_NUMBER,
-            .help = "limit total I/O operations per second",
-        },{
-            .name = "iops_rd",
-            .type = QEMU_OPT_NUMBER,
-            .help = "limit read operations per second",
-        },{
-            .name = "iops_wr",
-            .type = QEMU_OPT_NUMBER,
-            .help = "limit write operations per second",
-        },{
-            .name = "bps",
-            .type = QEMU_OPT_NUMBER,
-            .help = "limit total bytes per second",
-        },{
-            .name = "bps_rd",
-            .type = QEMU_OPT_NUMBER,
-            .help = "limit read bytes per second",
-        },{
-            .name = "bps_wr",
-            .type = QEMU_OPT_NUMBER,
-            .help = "limit write bytes per second",
-        },{
-            .name = "copy-on-read",
-            .type = QEMU_OPT_BOOL,
-            .help = "copy read data from backing file into image file",
-        },{
-            .name = "boot",
-            .type = QEMU_OPT_BOOL,
-            .help = "(deprecated, ignored)",
-        },
+        /*
+         * no elements => accept any params
+         * validation will happen later
+         */
         { /* end of list */ }
     },
 };

tests/qemu-iotests/group

@@ -57,7 +57,7 @@
 048 img auto quick
 049 rw auto
 050 rw auto backing quick
-#051 rw auto
+051 rw auto
 052 rw auto backing
 053 rw auto
 054 rw auto