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Diffstat (limited to 'qemu-img.c')
-rw-r--r--qemu-img.c317
1 files changed, 267 insertions, 50 deletions
diff --git a/qemu-img.c b/qemu-img.c
index b9a848db74..3e5e388d1c 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -103,6 +103,8 @@ static void help(void)
            "  '-S' indicates the consecutive number of bytes that must contain only zeros\n"
            "       for qemu-img to create a sparse image during conversion\n"
            "  '--output' takes the format in which the output must be done (human or json)\n"
+           "  '-n' skips the target volume creation (useful if the volume is created\n"
+           "       prior to running qemu-img)\n"
            "\n"
            "Parameters to check subcommand:\n"
            "  '-r' tries to repair any inconsistencies that are found during the check.\n"
@@ -298,7 +300,7 @@ static BlockDriverState *bdrv_new_open(const char *filename,
     return bs;
 fail:
     if (bs) {
-        bdrv_delete(bs);
+        bdrv_unref(bs);
     }
     return NULL;
 }
@@ -652,7 +654,7 @@ static int img_check(int argc, char **argv)
 
 fail:
     qapi_free_ImageCheck(check);
-    bdrv_delete(bs);
+    bdrv_unref(bs);
 
     return ret;
 }
@@ -722,7 +724,7 @@ static int img_commit(int argc, char **argv)
         break;
     }
 
-    bdrv_delete(bs);
+    bdrv_unref(bs);
     if (ret) {
         return 1;
     }
@@ -1104,11 +1106,11 @@ static int img_compare(int argc, char **argv)
     ret = 0;
 
 out:
-    bdrv_delete(bs2);
+    bdrv_unref(bs2);
     qemu_vfree(buf1);
     qemu_vfree(buf2);
 out2:
-    bdrv_delete(bs1);
+    bdrv_unref(bs1);
 out3:
     qemu_progress_end();
     return ret;
@@ -1116,7 +1118,8 @@ out3:
 
 static int img_convert(int argc, char **argv)
 {
-    int c, ret = 0, n, n1, bs_n, bs_i, compress, cluster_size, cluster_sectors;
+    int c, ret = 0, n, n1, bs_n, bs_i, compress, cluster_size,
+        cluster_sectors, skip_create;
     int progress = 0, flags;
     const char *fmt, *out_fmt, *cache, *out_baseimg, *out_filename;
     BlockDriver *drv, *proto_drv;
@@ -1139,8 +1142,9 @@ static int img_convert(int argc, char **argv)
     cache = "unsafe";
     out_baseimg = NULL;
     compress = 0;
+    skip_create = 0;
     for(;;) {
-        c = getopt(argc, argv, "f:O:B:s:hce6o:pS:t:q");
+        c = getopt(argc, argv, "f:O:B:s:hce6o:pS:t:qn");
         if (c == -1) {
             break;
         }
@@ -1197,6 +1201,9 @@ static int img_convert(int argc, char **argv)
         case 'q':
             quiet = true;
             break;
+        case 'n':
+            skip_create = 1;
+            break;
         }
     }
 
@@ -1329,20 +1336,22 @@ static int img_convert(int argc, char **argv)
         }
     }
 
-    /* Create the new image */
-    ret = bdrv_create(drv, out_filename, param);
-    if (ret < 0) {
-        if (ret == -ENOTSUP) {
-            error_report("Formatting not supported for file format '%s'",
-                         out_fmt);
-        } else if (ret == -EFBIG) {
-            error_report("The image size is too large for file format '%s'",
-                         out_fmt);
-        } else {
-            error_report("%s: error while converting %s: %s",
-                         out_filename, out_fmt, strerror(-ret));
+    if (!skip_create) {
+        /* Create the new image */
+        ret = bdrv_create(drv, out_filename, param);
+        if (ret < 0) {
+            if (ret == -ENOTSUP) {
+                error_report("Formatting not supported for file format '%s'",
+                             out_fmt);
+            } else if (ret == -EFBIG) {
+                error_report("The image size is too large for file format '%s'",
+                             out_fmt);
+            } else {
+                error_report("%s: error while converting %s: %s",
+                             out_filename, out_fmt, strerror(-ret));
+            }
+            goto out;
         }
-        goto out;
     }
 
     flags = BDRV_O_RDWR;
@@ -1363,6 +1372,20 @@ static int img_convert(int argc, char **argv)
     bdrv_get_geometry(bs[0], &bs_sectors);
     buf = qemu_blockalign(out_bs, IO_BUF_SIZE);
 
+    if (skip_create) {
+        int64_t output_length = bdrv_getlength(out_bs);
+        if (output_length < 0) {
+            error_report("unable to get output image length: %s\n",
+                         strerror(-output_length));
+            ret = -1;
+            goto out;
+        } else if (output_length < total_sectors << BDRV_SECTOR_BITS) {
+            error_report("output file is smaller than input file");
+            ret = -1;
+            goto out;
+        }
+    }
+
     if (compress) {
         ret = bdrv_get_info(out_bs, &bdi);
         if (ret < 0) {
@@ -1479,21 +1502,26 @@ static int img_convert(int argc, char **argv)
                 n = bs_offset + bs_sectors - sector_num;
             }
 
-            if (has_zero_init) {
-                /* If the output image is being created as a copy on write image,
-                   assume that sectors which are unallocated in the input image
-                   are present in both the output's and input's base images (no
-                   need to copy them). */
-                if (out_baseimg) {
-                    if (!bdrv_is_allocated(bs[bs_i], sector_num - bs_offset,
-                                           n, &n1)) {
-                        sector_num += n1;
-                        continue;
-                    }
-                    /* The next 'n1' sectors are allocated in the input image. Copy
-                       only those as they may be followed by unallocated sectors. */
-                    n = n1;
+            /* If the output image is being created as a copy on write image,
+               assume that sectors which are unallocated in the input image
+               are present in both the output's and input's base images (no
+               need to copy them). */
+            if (out_baseimg) {
+                ret = bdrv_is_allocated(bs[bs_i], sector_num - bs_offset,
+                                        n, &n1);
+                if (ret < 0) {
+                    error_report("error while reading metadata for sector "
+                                 "%" PRId64 ": %s",
+                                 sector_num - bs_offset, strerror(-ret));
+                    goto out;
                 }
+                if (!ret) {
+                    sector_num += n1;
+                    continue;
+                }
+                /* The next 'n1' sectors are allocated in the input image. Copy
+                   only those as they may be followed by unallocated sectors. */
+                n = n1;
             } else {
                 n1 = n;
             }
@@ -1509,14 +1537,7 @@ static int img_convert(int argc, char **argv)
                should add a specific call to have the info to go faster */
             buf1 = buf;
             while (n > 0) {
-                /* If the output image is being created as a copy on write image,
-                   copy all sectors even the ones containing only NUL bytes,
-                   because they may differ from the sectors in the base image.
-
-                   If the output is to a host device, we also write out
-                   sectors that are entirely 0, since whatever data was
-                   already there is garbage, not 0s. */
-                if (!has_zero_init || out_baseimg ||
+                if (!has_zero_init ||
                     is_allocated_sectors_min(buf1, n, &n1, min_sparse)) {
                     ret = bdrv_write(out_bs, sector_num, buf1, n1);
                     if (ret < 0) {
@@ -1538,12 +1559,12 @@ out:
     free_option_parameters(param);
     qemu_vfree(buf);
     if (out_bs) {
-        bdrv_delete(out_bs);
+        bdrv_unref(out_bs);
     }
     if (bs) {
         for (bs_i = 0; bs_i < bs_n; bs_i++) {
             if (bs[bs_i]) {
-                bdrv_delete(bs[bs_i]);
+                bdrv_unref(bs[bs_i]);
             }
         }
         g_free(bs);
@@ -1681,7 +1702,7 @@ static ImageInfoList *collect_image_info_list(const char *filename,
         *last = elem;
         last = &elem->next;
 
-        bdrv_delete(bs);
+        bdrv_unref(bs);
 
         filename = fmt = NULL;
         if (chain) {
@@ -1780,6 +1801,197 @@ static int img_info(int argc, char **argv)
     return 0;
 }
 
+
+typedef struct MapEntry {
+    int flags;
+    int depth;
+    int64_t start;
+    int64_t length;
+    int64_t offset;
+    BlockDriverState *bs;
+} MapEntry;
+
+static void dump_map_entry(OutputFormat output_format, MapEntry *e,
+                           MapEntry *next)
+{
+    switch (output_format) {
+    case OFORMAT_HUMAN:
+        if ((e->flags & BDRV_BLOCK_DATA) &&
+            !(e->flags & BDRV_BLOCK_OFFSET_VALID)) {
+            error_report("File contains external, encrypted or compressed clusters.");
+            exit(1);
+        }
+        if ((e->flags & (BDRV_BLOCK_DATA|BDRV_BLOCK_ZERO)) == BDRV_BLOCK_DATA) {
+            printf("%#-16"PRIx64"%#-16"PRIx64"%#-16"PRIx64"%s\n",
+                   e->start, e->length, e->offset, e->bs->filename);
+        }
+        /* This format ignores the distinction between 0, ZERO and ZERO|DATA.
+         * Modify the flags here to allow more coalescing.
+         */
+        if (next &&
+            (next->flags & (BDRV_BLOCK_DATA|BDRV_BLOCK_ZERO)) != BDRV_BLOCK_DATA) {
+            next->flags &= ~BDRV_BLOCK_DATA;
+            next->flags |= BDRV_BLOCK_ZERO;
+        }
+        break;
+    case OFORMAT_JSON:
+        printf("%s{ \"start\": %"PRId64", \"length\": %"PRId64", \"depth\": %d,"
+               " \"zero\": %s, \"data\": %s",
+               (e->start == 0 ? "[" : ",\n"),
+               e->start, e->length, e->depth,
+               (e->flags & BDRV_BLOCK_ZERO) ? "true" : "false",
+               (e->flags & BDRV_BLOCK_DATA) ? "true" : "false");
+        if (e->flags & BDRV_BLOCK_OFFSET_VALID) {
+            printf(", 'offset': %"PRId64"", e->offset);
+        }
+        putchar('}');
+
+        if (!next) {
+            printf("]\n");
+        }
+        break;
+    }
+}
+
+static int get_block_status(BlockDriverState *bs, int64_t sector_num,
+                            int nb_sectors, MapEntry *e)
+{
+    int64_t ret;
+    int depth;
+
+    /* As an optimization, we could cache the current range of unallocated
+     * clusters in each file of the chain, and avoid querying the same
+     * range repeatedly.
+     */
+
+    depth = 0;
+    for (;;) {
+        ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &nb_sectors);
+        if (ret < 0) {
+            return ret;
+        }
+        assert(nb_sectors);
+        if (ret & (BDRV_BLOCK_ZERO|BDRV_BLOCK_DATA)) {
+            break;
+        }
+        bs = bs->backing_hd;
+        if (bs == NULL) {
+            ret = 0;
+            break;
+        }
+
+        depth++;
+    }
+
+    e->start = sector_num * BDRV_SECTOR_SIZE;
+    e->length = nb_sectors * BDRV_SECTOR_SIZE;
+    e->flags = ret & ~BDRV_BLOCK_OFFSET_MASK;
+    e->offset = ret & BDRV_BLOCK_OFFSET_MASK;
+    e->depth = depth;
+    e->bs = bs;
+    return 0;
+}
+
+static int img_map(int argc, char **argv)
+{
+    int c;
+    OutputFormat output_format = OFORMAT_HUMAN;
+    BlockDriverState *bs;
+    const char *filename, *fmt, *output;
+    int64_t length;
+    MapEntry curr = { .length = 0 }, next;
+    int ret = 0;
+
+    fmt = NULL;
+    output = NULL;
+    for (;;) {
+        int option_index = 0;
+        static const struct option long_options[] = {
+            {"help", no_argument, 0, 'h'},
+            {"format", required_argument, 0, 'f'},
+            {"output", required_argument, 0, OPTION_OUTPUT},
+            {0, 0, 0, 0}
+        };
+        c = getopt_long(argc, argv, "f:h",
+                        long_options, &option_index);
+        if (c == -1) {
+            break;
+        }
+        switch (c) {
+        case '?':
+        case 'h':
+            help();
+            break;
+        case 'f':
+            fmt = optarg;
+            break;
+        case OPTION_OUTPUT:
+            output = optarg;
+            break;
+        }
+    }
+    if (optind >= argc) {
+        help();
+    }
+    filename = argv[optind++];
+
+    if (output && !strcmp(output, "json")) {
+        output_format = OFORMAT_JSON;
+    } else if (output && !strcmp(output, "human")) {
+        output_format = OFORMAT_HUMAN;
+    } else if (output) {
+        error_report("--output must be used with human or json as argument.");
+        return 1;
+    }
+
+    bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS, true, false);
+    if (!bs) {
+        return 1;
+    }
+
+    if (output_format == OFORMAT_HUMAN) {
+        printf("%-16s%-16s%-16s%s\n", "Offset", "Length", "Mapped to", "File");
+    }
+
+    length = bdrv_getlength(bs);
+    while (curr.start + curr.length < length) {
+        int64_t nsectors_left;
+        int64_t sector_num;
+        int n;
+
+        sector_num = (curr.start + curr.length) >> BDRV_SECTOR_BITS;
+
+        /* Probe up to 1 GiB at a time.  */
+        nsectors_left = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE) - sector_num;
+        n = MIN(1 << (30 - BDRV_SECTOR_BITS), nsectors_left);
+        ret = get_block_status(bs, sector_num, n, &next);
+
+        if (ret < 0) {
+            error_report("Could not read file metadata: %s", strerror(-ret));
+            goto out;
+        }
+
+        if (curr.length != 0 && curr.flags == next.flags &&
+            curr.depth == next.depth &&
+            ((curr.flags & BDRV_BLOCK_OFFSET_VALID) == 0 ||
+             curr.offset + curr.length == next.offset)) {
+            curr.length += next.length;
+            continue;
+        }
+
+        if (curr.length > 0) {
+            dump_map_entry(output_format, &curr, &next);
+        }
+        curr = next;
+    }
+
+    dump_map_entry(output_format, &curr, NULL);
+
+out:
+    bdrv_unref(bs);
+    return ret < 0;
+}
+
 #define SNAPSHOT_LIST   1
 #define SNAPSHOT_CREATE 2
 #define SNAPSHOT_APPLY  3
@@ -1895,7 +2107,7 @@ static int img_snapshot(int argc, char **argv)
     }
 
     /* Cleanup */
-    bdrv_delete(bs);
+    bdrv_unref(bs);
     if (ret) {
         return 1;
     }
@@ -2076,6 +2288,11 @@ static int img_rebase(int argc, char **argv)
 
             /* If the cluster is allocated, we don't need to take action */
             ret = bdrv_is_allocated(bs, sector, n, &n);
+            if (ret < 0) {
+                error_report("error while reading image metadata: %s",
+                             strerror(-ret));
+                goto out;
+            }
             if (ret) {
                 continue;
             }
@@ -2170,14 +2387,14 @@ out:
     /* Cleanup */
     if (!unsafe) {
         if (bs_old_backing != NULL) {
-            bdrv_delete(bs_old_backing);
+            bdrv_unref(bs_old_backing);
         }
         if (bs_new_backing != NULL) {
-            bdrv_delete(bs_new_backing);
+            bdrv_unref(bs_new_backing);
         }
     }
 
-    bdrv_delete(bs);
+    bdrv_unref(bs);
     if (ret) {
         return 1;
     }
@@ -2300,7 +2517,7 @@ static int img_resize(int argc, char **argv)
     }
 out:
     if (bs) {
-        bdrv_delete(bs);
+        bdrv_unref(bs);
     }
     if (ret) {
         return 1;