block: return get_block_status data and flags for formats

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

block/cow.c

@@ -191,7 +191,13 @@ static int coroutine_fn cow_co_is_allocated(BlockDriverState *bs,
 static int64_t coroutine_fn cow_co_get_block_status(BlockDriverState *bs,
         int64_t sector_num, int nb_sectors, int *num_same)
 {
-    return cow_co_is_allocated(bs, sector_num, nb_sectors, num_same);
+    BDRVCowState *s = bs->opaque;
+    int ret = cow_co_is_allocated(bs, sector_num, nb_sectors, num_same);
+    int64_t offset = s->cow_sectors_offset + (sector_num << BDRV_SECTOR_BITS);
+    if (ret < 0) {
+        return ret;
+    }
+    return (ret ? BDRV_BLOCK_DATA : 0) | offset | BDRV_BLOCK_OFFSET_VALID;
 }
 
 static int cow_update_bitmap(BlockDriverState *bs, int64_t sector_num,

block/qcow.c

@@ -410,7 +410,14 @@ static int64_t coroutine_fn qcow_co_get_block_status(BlockDriverState *bs,
     if (n > nb_sectors)
         n = nb_sectors;
     *pnum = n;
-    return (cluster_offset != 0);
+    if (!cluster_offset) {
+        return 0;
+    }
+    if ((cluster_offset & QCOW_OFLAG_COMPRESSED) || s->crypt_method) {
+        return BDRV_BLOCK_DATA;
+    }
+    cluster_offset |= (index_in_cluster << BDRV_SECTOR_BITS);
+    return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | cluster_offset;
 }
 
 static int decompress_buffer(uint8_t *out_buf, int out_buf_size,

block/qcow2.c

@@ -693,7 +693,8 @@ static int64_t coroutine_fn qcow2_co_get_block_status(BlockDriverState *bs,
 {
     BDRVQcowState *s = bs->opaque;
     uint64_t cluster_offset;
-    int ret;
+    int index_in_cluster, ret;
+    int64_t status = 0;
 
     *pnum = nb_sectors;
     qemu_co_mutex_lock(&s->lock);
@@ -703,7 +704,18 @@ static int64_t coroutine_fn qcow2_co_get_block_status(BlockDriverState *bs,
         return ret;
     }
 
-    return (cluster_offset != 0) || (ret == QCOW2_CLUSTER_ZERO);
+    if (cluster_offset != 0 && ret != QCOW2_CLUSTER_COMPRESSED &&
+        !s->crypt_method) {
+        index_in_cluster = sector_num & (s->cluster_sectors - 1);
+        cluster_offset |= (index_in_cluster << BDRV_SECTOR_BITS);
+        status |= BDRV_BLOCK_OFFSET_VALID | cluster_offset;
+    }
+    if (ret == QCOW2_CLUSTER_ZERO) {
+        status |= BDRV_BLOCK_ZERO;
+    } else if (ret != QCOW2_CLUSTER_UNALLOCATED) {
+        status |= BDRV_BLOCK_DATA;
+    }
+    return status;
 }
 
 /* handle reading after the end of the backing file */

block/qed.c

@@ -652,16 +652,36 @@ static int bdrv_qed_create(const char *filename, QEMUOptionParameter *options)
 }
 
 typedef struct {
+    BlockDriverState *bs;
     Coroutine *co;
-    int is_allocated;
+    uint64_t pos;
+    int64_t status;
     int *pnum;
 } QEDIsAllocatedCB;
 
 static void qed_is_allocated_cb(void *opaque, int ret, uint64_t offset, size_t len)
 {
     QEDIsAllocatedCB *cb = opaque;
+    BDRVQEDState *s = cb->bs->opaque;
     *cb->pnum = len / BDRV_SECTOR_SIZE;
-    cb->is_allocated = (ret == QED_CLUSTER_FOUND || ret == QED_CLUSTER_ZERO);
+    switch (ret) {
+    case QED_CLUSTER_FOUND:
+        offset |= qed_offset_into_cluster(s, cb->pos);
+        cb->status = BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | offset;
+        break;
+    case QED_CLUSTER_ZERO:
+        cb->status = BDRV_BLOCK_ZERO;
+        break;
+    case QED_CLUSTER_L2:
+    case QED_CLUSTER_L1:
+        cb->status = 0;
+        break;
+    default:
+        assert(ret < 0);
+        cb->status = ret;
+        break;
+    }
+
     if (cb->co) {
         qemu_coroutine_enter(cb->co, NULL);
     }
@@ -672,25 +692,26 @@ static int64_t coroutine_fn bdrv_qed_co_get_block_status(BlockDriverState *bs,
                                                  int nb_sectors, int *pnum)
 {
     BDRVQEDState *s = bs->opaque;
-    uint64_t pos = (uint64_t)sector_num * BDRV_SECTOR_SIZE;
     size_t len = (size_t)nb_sectors * BDRV_SECTOR_SIZE;
     QEDIsAllocatedCB cb = {
-        .is_allocated = -1,
+        .bs = bs,
+        .pos = (uint64_t)sector_num * BDRV_SECTOR_SIZE,
+        .status = BDRV_BLOCK_OFFSET_MASK,
         .pnum = pnum,
     };
     QEDRequest request = { .l2_table = NULL };
 
-    qed_find_cluster(s, &request, pos, len, qed_is_allocated_cb, &cb);
+    qed_find_cluster(s, &request, cb.pos, len, qed_is_allocated_cb, &cb);
 
     /* Now sleep if the callback wasn't invoked immediately */
-    while (cb.is_allocated == -1) {
+    while (cb.status == BDRV_BLOCK_OFFSET_MASK) {
         cb.co = qemu_coroutine_self();
         qemu_coroutine_yield();
     }
 
     qed_unref_l2_cache_entry(request.l2_table);
 
-    return cb.is_allocated;
+    return cb.status;
 }
 
 static int bdrv_qed_make_empty(BlockDriverState *bs)

block/sheepdog.c

@@ -2280,7 +2280,7 @@ sd_co_get_block_status(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
                   end = DIV_ROUND_UP((sector_num + nb_sectors) *
                                      BDRV_SECTOR_SIZE, SD_DATA_OBJ_SIZE);
     unsigned long idx;
-    int ret = 1;
+    int64_t ret = BDRV_BLOCK_DATA;
 
     for (idx = start; idx < end; idx++) {
         if (inode->data_vdi_id[idx] == 0) {

block/vdi.c

@@ -479,12 +479,23 @@ static int64_t coroutine_fn vdi_co_get_block_status(BlockDriverState *bs,
     size_t sector_in_block = sector_num % s->block_sectors;
     int n_sectors = s->block_sectors - sector_in_block;
     uint32_t bmap_entry = le32_to_cpu(s->bmap[bmap_index]);
+    uint64_t offset;
+    int result;
+
     logout("%p, %" PRId64 ", %d, %p\n", bs, sector_num, nb_sectors, pnum);
     if (n_sectors > nb_sectors) {
         n_sectors = nb_sectors;
     }
     *pnum = n_sectors;
-    return VDI_IS_ALLOCATED(bmap_entry);
+    result = VDI_IS_ALLOCATED(bmap_entry);
+    if (!result) {
+        return 0;
+    }
+
+    offset = s->header.offset_data +
+                              (uint64_t)bmap_entry * s->block_size +
+                              sector_in_block * SECTOR_SIZE;
+    return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | offset;
 }
 
 static int vdi_co_read(BlockDriverState *bs,

block/vmdk.c

@@ -1059,7 +1059,24 @@ static int64_t coroutine_fn vmdk_co_get_block_status(BlockDriverState *bs,
                             sector_num * 512, 0, &offset);
     qemu_co_mutex_unlock(&s->lock);
 
-    ret = (ret == VMDK_OK || ret == VMDK_ZEROED);
+    switch (ret) {
+    case VMDK_ERROR:
+        ret = -EIO;
+        break;
+    case VMDK_UNALLOC:
+        ret = 0;
+        break;
+    case VMDK_ZEROED:
+        ret = BDRV_BLOCK_ZERO;
+        break;
+    case VMDK_OK:
+        ret = BDRV_BLOCK_DATA;
+        if (extent->file == bs->file) {
+            ret |= BDRV_BLOCK_OFFSET_VALID | offset;
+        }
+
+        break;
+    }
 
     index_in_cluster = sector_num % extent->cluster_sectors;
     n = extent->cluster_sectors - index_in_cluster;

block/vvfat.c

@@ -2879,11 +2879,12 @@ static int64_t coroutine_fn vvfat_co_get_block_status(BlockDriverState *bs,
 {
     BDRVVVFATState* s = bs->opaque;
     *n = s->sector_count - sector_num;
-    if (*n > nb_sectors)
+    if (*n > nb_sectors) {
-	*n = nb_sectors;
+        *n = nb_sectors;
-    else if (*n < 0)
+    } else if (*n < 0) {
-	return 0;
+        return 0;
-    return 1;
+    }
+    return BDRV_BLOCK_DATA;
 }
 
 static int write_target_commit(BlockDriverState *bs, int64_t sector_num,