Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2020-05-18' into staging

nbd patches for 2020-05-20

- fix stranded fd in 'qemu-nbd -c /dev/nbd0'
- add 'qemu-img map --start-offset --max-length' options

# gpg: Signature made Mon 18 May 2020 17:29:56 BST
# gpg:                using RSA key 71C2CC22B1C4602927D2F3AAA7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>" [full]
# gpg:                 aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>" [full]
# gpg:                 aka "[jpeg image of size 6874]" [full]
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2  F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-nbd-2020-05-18:
  iotests: Enhance 223 to cover qemu-img map improvements
  qemu-img: Add --start-offset and --max-length to map
  qemu-img: refactor dump_map_entry JSON format output
  qemu-img: validate image length in img_map
  qemu_img: add cvtnum_full to print error reports
  qemu-nbd: Close inherited stderr

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

7 files changed, 86 insertions, 58 deletions

diff --git a/docs/tools/qemu-img.rst b/docs/tools/qemu-img.rst
index 0080f83a76..f4ffe528ea 100644
--- a/docs/tools/qemu-img.rst
+++ b/docs/tools/qemu-img.rst
@@ -519,7 +519,7 @@ Command description:
     ``ImageInfoSpecific*`` QAPI object (e.g. ``ImageInfoSpecificQCow2``
     for qcow2 images).
 
-.. option:: map [--object OBJECTDEF] [--image-opts] [-f FMT] [--output=OFMT] [-U] FILENAME
+.. option:: map [--object OBJECTDEF] [--image-opts] [-f FMT] [--start-offset=OFFSET] [--max-length=LEN] [--output=OFMT] [-U] FILENAME
 
   Dump the metadata of image *FILENAME* and its backing file chain.
   In particular, this commands dumps the allocation state of every sector
diff --git a/qemu-img-cmds.hx b/qemu-img-cmds.hx
index c9c54de1df..35f832816f 100644
--- a/qemu-img-cmds.hx
+++ b/qemu-img-cmds.hx
@@ -63,9 +63,9 @@ SRST
 ERST
 
 DEF("map", img_map,
-    "map [--object objectdef] [--image-opts] [-f fmt] [--output=ofmt] [-U] filename")
+    "map [--object objectdef] [--image-opts] [-f fmt] [--start-offset=offset] [--max-length=len] [--output=ofmt] [-U] filename")
 SRST
-.. option:: map [--object OBJECTDEF] [--image-opts] [-f FMT] [--output=OFMT] [-U] FILENAME
+.. option:: map [--object OBJECTDEF] [--image-opts] [-f FMT] [--start-offset=OFFSET] [--max-length=LEN] [--output=OFMT] [-U] FILENAME
 ERST
 
 DEF("measure", img_measure,
diff --git a/qemu-img.c b/qemu-img.c
index 6a4327aaba..947bf8b34b 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -470,19 +470,31 @@ static int add_old_style_options(const char *fmt, QemuOpts *opts,
     return 0;
 }
 
-static int64_t cvtnum(const char *s)
+static int64_t cvtnum_full(const char *name, const char *value, int64_t min,
+                           int64_t max)
 {
     int err;
-    uint64_t value;
-
-    err = qemu_strtosz(s, NULL, &value);
-    if (err < 0) {
+    uint64_t res;
+
+    err = qemu_strtosz(value, NULL, &res);
+    if (err < 0 && err != -ERANGE) {
+        error_report("Invalid %s specified. You may use "
+                     "k, M, G, T, P or E suffixes for", name);
+        error_report("kilobytes, megabytes, gigabytes, terabytes, "
+                     "petabytes and exabytes.");
         return err;
     }
-    if (value > INT64_MAX) {
+    if (err == -ERANGE || res > max || res < min) {
+        error_report("Invalid %s specified. Must be between %" PRId64
+                     " and %" PRId64 ".", name, min, max);
         return -ERANGE;
     }
-    return value;
+    return res;
+}
+
+static int64_t cvtnum(const char *name, const char *value)
+{
+    return cvtnum_full(name, value, 0, INT64_MAX);
 }
 
 static int img_create(int argc, char **argv)
@@ -572,16 +584,8 @@ static int img_create(int argc, char **argv)
     if (optind < argc) {
         int64_t sval;
 
-        sval = cvtnum(argv[optind++]);
+        sval = cvtnum("image size", argv[optind++]);
         if (sval < 0) {
-            if (sval == -ERANGE) {
-                error_report("Image size must be less than 8 EiB!");
-            } else {
-                error_report("Invalid image size specified! You may use k, M, "
-                      "G, T, P or E suffixes for ");
-                error_report("kilobytes, megabytes, gigabytes, terabytes, "
-                             "petabytes and exabytes.");
-            }
             goto fail;
         }
         img_size = (uint64_t)sval;
@@ -2187,8 +2191,10 @@ static int img_convert(int argc, char **argv)
         {
             int64_t sval;
 
-            sval = cvtnum(optarg);
-            if (sval < 0 || !QEMU_IS_ALIGNED(sval, BDRV_SECTOR_SIZE) ||
+            sval = cvtnum("buffer size for sparse output", optarg);
+            if (sval < 0) {
+                goto fail_getopt;
+            } else if (!QEMU_IS_ALIGNED(sval, BDRV_SECTOR_SIZE) ||
                 sval / BDRV_SECTOR_SIZE > MAX_BUF_SECTORS) {
                 error_report("Invalid buffer size for sparse output specified. "
                     "Valid sizes are multiples of %llu up to %llu. Select "
@@ -2896,9 +2902,8 @@ static int dump_map_entry(OutputFormat output_format, MapEntry *e,
         }
         break;
     case OFORMAT_JSON:
-        printf("%s{ \"start\": %"PRId64", \"length\": %"PRId64","
+        printf("{ \"start\": %"PRId64", \"length\": %"PRId64","
                " \"depth\": %"PRId64", \"zero\": %s, \"data\": %s",
-               (e->start == 0 ? "[" : ",\n"),
                e->start, e->length, e->depth,
                e->zero ? "true" : "false",
                e->data ? "true" : "false");
@@ -2907,8 +2912,8 @@ static int dump_map_entry(OutputFormat output_format, MapEntry *e,
         }
         putchar('}');
 
-        if (!next) {
-            printf("]\n");
+        if (next) {
+            puts(",");
         }
         break;
     }
@@ -3004,6 +3009,8 @@ static int img_map(int argc, char **argv)
     int ret = 0;
     bool image_opts = false;
     bool force_share = false;
+    int64_t start_offset = 0;
+    int64_t max_length = -1;
 
     fmt = NULL;
     output = NULL;
@@ -3016,9 +3023,11 @@ static int img_map(int argc, char **argv)
             {"object", required_argument, 0, OPTION_OBJECT},
             {"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
             {"force-share", no_argument, 0, 'U'},
+            {"start-offset", required_argument, 0, 's'},
+            {"max-length", required_argument, 0, 'l'},
             {0, 0, 0, 0}
         };
-        c = getopt_long(argc, argv, ":f:hU",
+        c = getopt_long(argc, argv, ":f:s:l:hU",
                         long_options, &option_index);
         if (c == -1) {
             break;
@@ -3042,6 +3051,18 @@ static int img_map(int argc, char **argv)
         case OPTION_OUTPUT:
             output = optarg;
             break;
+        case 's':
+            start_offset = cvtnum("start offset", optarg);
+            if (start_offset < 0) {
+                return 1;
+            }
+            break;
+        case 'l':
+            max_length = cvtnum("max length", optarg);
+            if (max_length < 0) {
+                return 1;
+            }
+            break;
         case OPTION_OBJECT: {
             QemuOpts *opts;
             opts = qemu_opts_parse_noisily(&qemu_object_opts,
@@ -3083,9 +3104,20 @@ static int img_map(int argc, char **argv)
 
     if (output_format == OFORMAT_HUMAN) {
         printf("%-16s%-16s%-16s%s\n", "Offset", "Length", "Mapped to", "File");
+    } else if (output_format == OFORMAT_JSON) {
+        putchar('[');
     }
 
     length = blk_getlength(blk);
+    if (length < 0) {
+        error_report("Failed to get size for '%s'", filename);
+        return 1;
+    }
+    if (max_length != -1) {
+        length = MIN(start_offset + max_length, length);
+    }
+
+    curr.start = start_offset;
     while (curr.start + curr.length < length) {
         int64_t offset = curr.start + curr.length;
         int64_t n;
@@ -3114,6 +3146,9 @@ static int img_map(int argc, char **argv)
     }
 
     ret = dump_map_entry(output_format, &curr, NULL);
+    if (output_format == OFORMAT_JSON) {
+        puts("]");
+    }
 
 out:
     blk_unref(blk);
@@ -4291,9 +4326,8 @@ static int img_bench(int argc, char **argv)
             break;
         case 'o':
         {
-            offset = cvtnum(optarg);
+            offset = cvtnum("offset", optarg);
             if (offset < 0) {
-                error_report("Invalid offset specified");
                 return 1;
             }
             break;
@@ -4306,9 +4340,8 @@ static int img_bench(int argc, char **argv)
         {
             int64_t sval;
 
-            sval = cvtnum(optarg);
-            if (sval < 0 || sval > INT_MAX) {
-                error_report("Invalid buffer size specified");
+            sval = cvtnum_full("buffer size", optarg, 0, INT_MAX);
+            if (sval < 0) {
                 return 1;
             }
 
@@ -4319,9 +4352,8 @@ static int img_bench(int argc, char **argv)
         {
             int64_t sval;
 
-            sval = cvtnum(optarg);
-            if (sval < 0 || sval > INT_MAX) {
-                error_report("Invalid step size specified");
+            sval = cvtnum_full("step_size", optarg, 0, INT_MAX);
+            if (sval < 0) {
                 return 1;
             }
 
@@ -4491,10 +4523,9 @@ static int img_dd_bs(const char *arg,
 {
     int64_t res;
 
-    res = cvtnum(arg);
+    res = cvtnum_full("bs", arg, 1, INT_MAX);
 
-    if (res <= 0 || res > INT_MAX) {
-        error_report("invalid number: '%s'", arg);
+    if (res < 0) {
         return 1;
     }
     in->bsz = out->bsz = res;
@@ -4506,10 +4537,9 @@ static int img_dd_count(const char *arg,
                         struct DdIo *in, struct DdIo *out,
                         struct DdInfo *dd)
 {
-    dd->count = cvtnum(arg);
+    dd->count = cvtnum("count", arg);
 
     if (dd->count < 0) {
-        error_report("invalid number: '%s'", arg);
         return 1;
     }
 
@@ -4538,10 +4568,9 @@ static int img_dd_skip(const char *arg,
                        struct DdIo *in, struct DdIo *out,
                        struct DdInfo *dd)
 {
-    in->offset = cvtnum(arg);
+    in->offset = cvtnum("skip", arg);
 
     if (in->offset < 0) {
-        error_report("invalid number: '%s'", arg);
         return 1;
     }
 
@@ -4923,16 +4952,8 @@ static int img_measure(int argc, char **argv)
         {
             int64_t sval;
 
-            sval = cvtnum(optarg);
+            sval = cvtnum("image size", optarg);
             if (sval < 0) {
-                if (sval == -ERANGE) {
-                    error_report("Image size must be less than 8 EiB!");
-                } else {
-                    error_report("Invalid image size specified! You may use "
-                                 "k, M, G, T, P or E suffixes for ");
-                    error_report("kilobytes, megabytes, gigabytes, terabytes, "
-                                 "petabytes and exabytes.");
-                }
                 goto out;
             }
             img_size = (uint64_t)sval;
diff --git a/qemu-nbd.c b/qemu-nbd.c
index 4aa005004e..306e44fb0a 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -916,7 +916,11 @@ int main(int argc, char **argv)
         } else if (pid == 0) {
             close(stderr_fd[0]);
 
-            old_stderr = dup(STDERR_FILENO);
+            /* Remember parent's stderr if we will be restoring it. */
+            if (fork_process) {
+                old_stderr = dup(STDERR_FILENO);
+            }
+
             ret = qemu_daemon(1, 0);
 
             /* Temporarily redirect stderr to the parent's pipe...  */
diff --git a/tests/qemu-iotests/049.out b/tests/qemu-iotests/049.out
index a5cfba1756..c54ae21b86 100644
--- a/tests/qemu-iotests/049.out
+++ b/tests/qemu-iotests/049.out
@@ -92,19 +92,19 @@ Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1649267441664 cluster_size=65536 l
 == 3. Invalid sizes ==
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- -1024
-qemu-img: Image size must be less than 8 EiB!
+qemu-img: Invalid image size specified. Must be between 0 and 9223372036854775807.
 
 qemu-img create -f qcow2 -o size=-1024 TEST_DIR/t.qcow2
 qemu-img: TEST_DIR/t.qcow2: Value '-1024' is out of range for parameter 'size'
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- -1k
-qemu-img: Image size must be less than 8 EiB!
+qemu-img: Invalid image size specified. Must be between 0 and 9223372036854775807.
 
 qemu-img create -f qcow2 -o size=-1k TEST_DIR/t.qcow2
 qemu-img: TEST_DIR/t.qcow2: Value '-1k' is out of range for parameter 'size'
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- 1kilobyte
-qemu-img: Invalid image size specified! You may use k, M, G, T, P or E suffixes for
+qemu-img: Invalid image size specified. You may use k, M, G, T, P or E suffixes for
 qemu-img: kilobytes, megabytes, gigabytes, terabytes, petabytes and exabytes.
 
 qemu-img create -f qcow2 -o size=1kilobyte TEST_DIR/t.qcow2
@@ -113,7 +113,7 @@ Optional suffix k, M, G, T, P or E means kilo-, mega-, giga-, tera-, peta-
 and exabytes, respectively.
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- foobar
-qemu-img: Invalid image size specified! You may use k, M, G, T, P or E suffixes for
+qemu-img: Invalid image size specified. You may use k, M, G, T, P or E suffixes for
 qemu-img: kilobytes, megabytes, gigabytes, terabytes, petabytes and exabytes.
 
 qemu-img create -f qcow2 -o size=foobar TEST_DIR/t.qcow2
diff --git a/tests/qemu-iotests/223 b/tests/qemu-iotests/223
index 56fbc5fb09..d68bc3cb6f 100755
--- a/tests/qemu-iotests/223
+++ b/tests/qemu-iotests/223
@@ -2,7 +2,7 @@
 #
 # Test reading dirty bitmap over NBD
 #
-# Copyright (C) 2018-2019 Red Hat, Inc.
+# Copyright (C) 2018-2020 Red Hat, Inc.
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -206,7 +206,9 @@ $QEMU_IMG map --output=json --image-opts \
 
 nbd_server_start_unix_socket -f $IMGFMT -B b2 "$TEST_IMG"
 IMG="driver=nbd,server.type=unix,server.path=$nbd_unix_socket"
-$QEMU_IMG map --output=json --image-opts \
+$QEMU_IMG map --output=json --image-opts --max-length=12345 \
+  "$IMG,x-dirty-bitmap=qemu:dirty-bitmap:b2" | _filter_qemu_img_map
+$QEMU_IMG map --output=json --image-opts --start-offset=12345 \
   "$IMG,x-dirty-bitmap=qemu:dirty-bitmap:b2" | _filter_qemu_img_map
 
 # success, all done
diff --git a/tests/qemu-iotests/223.out b/tests/qemu-iotests/223.out
index 80c0cf6509..e1eaaedb55 100644
--- a/tests/qemu-iotests/223.out
+++ b/tests/qemu-iotests/223.out
@@ -201,6 +201,7 @@ read 2097152/2097152 bytes at offset 2097152
 { "start": 2097152, "length": 2097152, "depth": 0, "zero": false, "data": false}]
 [{ "start": 0, "length": 512, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
 { "start": 512, "length": 512, "depth": 0, "zero": false, "data": false},
-{ "start": 1024, "length": 2096128, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 1024, "length": 11321, "depth": 0, "zero": false, "data": true, "offset": OFFSET}]
+[{ "start": 12345, "length": 2084807, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
 { "start": 2097152, "length": 2097152, "depth": 0, "zero": false, "data": false}]
 *** done