From: Fam Zheng <famz@redhat.com>
To: qemu-devel@nongnu.org
Cc: Kevin Wolf <kwolf@redhat.com>, Max Reitz <mreitz@redhat.com>,
qemu-block@nongnu.org
Subject: [Qemu-devel] [PATCH RFC 2/3] qemu-img: Add --unsafe-read option to subcommands
Date: Tue, 14 Mar 2017 10:39:32 +0800 [thread overview]
Message-ID: <20170314023933.12118-3-famz@redhat.com> (raw)
In-Reply-To: <20170314023933.12118-1-famz@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
---
qemu-img.c | 148 +++++++++++++++++++++++++++++++++++++++++++++++--------------
1 file changed, 114 insertions(+), 34 deletions(-)
diff --git a/qemu-img.c b/qemu-img.c
index 98b836b..3aaa254 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -273,12 +273,15 @@ static int img_open_password(BlockBackend *blk, const char *filename,
static BlockBackend *img_open_opts(const char *optstr,
QemuOpts *opts, int flags, bool writethrough,
- bool quiet)
+ bool quiet, bool unsafe)
{
QDict *options;
Error *local_err = NULL;
BlockBackend *blk;
options = qemu_opts_to_qdict(opts, NULL);
+ if (unsafe) {
+ flags |= BDRV_O_UNSAFE_READ;
+ }
blk = blk_new_open(NULL, NULL, options, flags, &local_err);
if (!blk) {
error_reportf_err(local_err, "Could not open '%s': ", optstr);
@@ -295,7 +298,7 @@ static BlockBackend *img_open_opts(const char *optstr,
static BlockBackend *img_open_file(const char *filename,
const char *fmt, int flags,
- bool writethrough, bool quiet)
+ bool writethrough, bool quiet, bool unsafe)
{
BlockBackend *blk;
Error *local_err = NULL;
@@ -306,6 +309,9 @@ static BlockBackend *img_open_file(const char *filename,
qdict_put(options, "driver", qstring_from_str(fmt));
}
+ if (unsafe) {
+ flags |= BDRV_O_UNSAFE_READ;
+ }
blk = blk_new_open(filename, NULL, options, flags, &local_err);
if (!blk) {
error_reportf_err(local_err, "Could not open '%s': ", filename);
@@ -324,7 +330,7 @@ static BlockBackend *img_open_file(const char *filename,
static BlockBackend *img_open(bool image_opts,
const char *filename,
const char *fmt, int flags, bool writethrough,
- bool quiet)
+ bool quiet, bool unsafe)
{
BlockBackend *blk;
if (image_opts) {
@@ -338,9 +344,9 @@ static BlockBackend *img_open(bool image_opts,
if (!opts) {
return NULL;
}
- blk = img_open_opts(filename, opts, flags, writethrough, quiet);
+ blk = img_open_opts(filename, opts, flags, writethrough, quiet, unsafe);
} else {
- blk = img_open_file(filename, fmt, flags, writethrough, quiet);
+ blk = img_open_file(filename, fmt, flags, writethrough, quiet, unsafe);
}
return blk;
}
@@ -635,6 +641,7 @@ static int img_check(int argc, char **argv)
ImageCheck *check;
bool quiet = false;
bool image_opts = false;
+ bool unsafe_read = false;
fmt = NULL;
output = NULL;
@@ -649,9 +656,10 @@ static int img_check(int argc, char **argv)
{"output", required_argument, 0, OPTION_OUTPUT},
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+ {"unsafe-read", no_argument, 0, 'U'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "hf:r:T:q",
+ c = getopt_long(argc, argv, "hf:r:T:qU",
long_options, &option_index);
if (c == -1) {
break;
@@ -685,6 +693,9 @@ static int img_check(int argc, char **argv)
case 'q':
quiet = true;
break;
+ case 'U':
+ unsafe_read = true;
+ break;
case OPTION_OBJECT: {
QemuOpts *opts;
opts = qemu_opts_parse_noisily(&qemu_object_opts,
@@ -724,7 +735,8 @@ static int img_check(int argc, char **argv)
return 1;
}
- blk = img_open(image_opts, filename, fmt, flags, writethrough, quiet);
+ blk = img_open(image_opts, filename, fmt, flags, writethrough, quiet,
+ unsafe_read);
if (!blk) {
return 1;
}
@@ -844,6 +856,7 @@ static int img_commit(int argc, char **argv)
CommonBlockJobCBInfo cbi;
bool image_opts = false;
AioContext *aio_context;
+ bool unsafe_read = false;
fmt = NULL;
cache = BDRV_DEFAULT_CACHE;
@@ -853,9 +866,10 @@ static int img_commit(int argc, char **argv)
{"help", no_argument, 0, 'h'},
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+ {"unsafe-read", no_argument, 0, 'U'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "f:ht:b:dpq",
+ c = getopt_long(argc, argv, "f:ht:b:dpqU",
long_options, NULL);
if (c == -1) {
break;
@@ -885,6 +899,9 @@ static int img_commit(int argc, char **argv)
case 'q':
quiet = true;
break;
+ case 'U':
+ unsafe_read = true;
+ break;
case OPTION_OBJECT: {
QemuOpts *opts;
opts = qemu_opts_parse_noisily(&qemu_object_opts,
@@ -922,7 +939,8 @@ static int img_commit(int argc, char **argv)
return 1;
}
- blk = img_open(image_opts, filename, fmt, flags, writethrough, quiet);
+ blk = img_open(image_opts, filename, fmt, flags, writethrough, quiet,
+ unsafe_read);
if (!blk) {
return 1;
}
@@ -1181,6 +1199,7 @@ static int img_compare(int argc, char **argv)
int c, pnum;
uint64_t progress_base;
bool image_opts = false;
+ bool unsafe_read = false;
cache = BDRV_DEFAULT_CACHE;
for (;;) {
@@ -1188,9 +1207,10 @@ static int img_compare(int argc, char **argv)
{"help", no_argument, 0, 'h'},
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+ {"unsafe-read", no_argument, 0, 'U'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "hf:F:T:pqs",
+ c = getopt_long(argc, argv, "hf:F:T:pqsU",
long_options, NULL);
if (c == -1) {
break;
@@ -1218,6 +1238,9 @@ static int img_compare(int argc, char **argv)
case 's':
strict = true;
break;
+ case 'U':
+ unsafe_read = true;
+ break;
case OPTION_OBJECT: {
QemuOpts *opts;
opts = qemu_opts_parse_noisily(&qemu_object_opts,
@@ -1263,13 +1286,15 @@ static int img_compare(int argc, char **argv)
goto out3;
}
- blk1 = img_open(image_opts, filename1, fmt1, flags, writethrough, quiet);
+ blk1 = img_open(image_opts, filename1, fmt1, flags, writethrough, quiet,
+ unsafe_read);
if (!blk1) {
ret = 2;
goto out3;
}
- blk2 = img_open(image_opts, filename2, fmt2, flags, writethrough, quiet);
+ blk2 = img_open(image_opts, filename2, fmt2, flags, writethrough, quiet,
+ unsafe_read);
if (!blk2) {
ret = 2;
goto out2;
@@ -1911,6 +1936,7 @@ static int img_convert(int argc, char **argv)
bool image_opts = false;
bool wr_in_order = true;
long num_coroutines = 8;
+ bool unsafe_read = false;
fmt = NULL;
out_fmt = "raw";
@@ -1924,9 +1950,10 @@ static int img_convert(int argc, char **argv)
{"help", no_argument, 0, 'h'},
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+ {"unsafe-read", no_argument, 0, 'U'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "hf:O:B:ce6o:s:l:S:pt:T:qnm:W",
+ c = getopt_long(argc, argv, "hf:O:B:ce6o:s:l:S:pt:T:qnm:WU",
long_options, NULL);
if (c == -1) {
break;
@@ -2030,6 +2057,9 @@ static int img_convert(int argc, char **argv)
case 'W':
wr_in_order = false;
break;
+ case 'U':
+ unsafe_read = true;
+ break;
case OPTION_OBJECT:
opts = qemu_opts_parse_noisily(&qemu_object_opts,
optarg, true);
@@ -2097,7 +2127,8 @@ static int img_convert(int argc, char **argv)
total_sectors = 0;
for (bs_i = 0; bs_i < bs_n; bs_i++) {
blk[bs_i] = img_open(image_opts, argv[optind + bs_i],
- fmt, src_flags, src_writethrough, quiet);
+ fmt, src_flags, src_writethrough, quiet,
+ unsafe_read);
if (!blk[bs_i]) {
ret = -1;
goto out;
@@ -2242,7 +2273,8 @@ static int img_convert(int argc, char **argv)
* the bdrv_create() call which takes different params.
* Not critical right now, so fix can wait...
*/
- out_blk = img_open_file(out_filename, out_fmt, flags, writethrough, quiet);
+ out_blk = img_open_file(out_filename, out_fmt, flags, writethrough, quiet,
+ unsafe_read);
if (!out_blk) {
ret = -1;
goto out;
@@ -2413,7 +2445,7 @@ static gboolean str_equal_func(gconstpointer a, gconstpointer b)
static ImageInfoList *collect_image_info_list(bool image_opts,
const char *filename,
const char *fmt,
- bool chain)
+ bool chain, bool unsafe)
{
ImageInfoList *head = NULL;
ImageInfoList **last = &head;
@@ -2436,7 +2468,8 @@ static ImageInfoList *collect_image_info_list(bool image_opts,
g_hash_table_insert(filenames, (gpointer)filename, NULL);
blk = img_open(image_opts, filename, fmt,
- BDRV_O_NO_BACKING | BDRV_O_NO_IO, false, false);
+ BDRV_O_NO_BACKING | BDRV_O_NO_IO, false, false,
+ unsafe);
if (!blk) {
goto err;
}
@@ -2488,6 +2521,7 @@ static int img_info(int argc, char **argv)
const char *filename, *fmt, *output;
ImageInfoList *list;
bool image_opts = false;
+ bool unsafe_read = false;
fmt = NULL;
output = NULL;
@@ -2500,9 +2534,10 @@ static int img_info(int argc, char **argv)
{"backing-chain", no_argument, 0, OPTION_BACKING_CHAIN},
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+ {"unsafe-read", no_argument, 0, 'U'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "f:h",
+ c = getopt_long(argc, argv, "f:hU",
long_options, &option_index);
if (c == -1) {
break;
@@ -2515,6 +2550,9 @@ static int img_info(int argc, char **argv)
case 'f':
fmt = optarg;
break;
+ case 'U':
+ unsafe_read = true;
+ break;
case OPTION_OUTPUT:
output = optarg;
break;
@@ -2554,7 +2592,8 @@ static int img_info(int argc, char **argv)
return 1;
}
- list = collect_image_info_list(image_opts, filename, fmt, chain);
+ list = collect_image_info_list(image_opts, filename, fmt, chain,
+ unsafe_read);
if (!list) {
return 1;
}
@@ -2700,6 +2739,7 @@ static int img_map(int argc, char **argv)
MapEntry curr = { .length = 0 }, next;
int ret = 0;
bool image_opts = false;
+ bool unsafe_read = false;
fmt = NULL;
output = NULL;
@@ -2711,9 +2751,10 @@ static int img_map(int argc, char **argv)
{"output", required_argument, 0, OPTION_OUTPUT},
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+ {"unsafe-read", no_argument, 0, 'U'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "f:h",
+ c = getopt_long(argc, argv, "f:hU",
long_options, &option_index);
if (c == -1) {
break;
@@ -2726,6 +2767,9 @@ static int img_map(int argc, char **argv)
case 'f':
fmt = optarg;
break;
+ case 'U':
+ unsafe_read = true;
+ break;
case OPTION_OUTPUT:
output = optarg;
break;
@@ -2762,7 +2806,7 @@ static int img_map(int argc, char **argv)
return 1;
}
- blk = img_open(image_opts, filename, fmt, 0, false, false);
+ blk = img_open(image_opts, filename, fmt, 0, false, false, unsafe_read);
if (!blk) {
return 1;
}
@@ -2825,6 +2869,7 @@ static int img_snapshot(int argc, char **argv)
bool quiet = false;
Error *err = NULL;
bool image_opts = false;
+ bool unsafe_read = false;
bdrv_oflags = BDRV_O_RDWR;
/* Parse commandline parameters */
@@ -2833,9 +2878,10 @@ static int img_snapshot(int argc, char **argv)
{"help", no_argument, 0, 'h'},
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+ {"unsafe-read", no_argument, 0, 'U'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "la:c:d:hq",
+ c = getopt_long(argc, argv, "la:c:d:hqU",
long_options, NULL);
if (c == -1) {
break;
@@ -2880,6 +2926,9 @@ static int img_snapshot(int argc, char **argv)
case 'q':
quiet = true;
break;
+ case 'U':
+ unsafe_read = true;
+ break;
case OPTION_OBJECT: {
QemuOpts *opts;
opts = qemu_opts_parse_noisily(&qemu_object_opts,
@@ -2906,7 +2955,8 @@ static int img_snapshot(int argc, char **argv)
}
/* Open the image */
- blk = img_open(image_opts, filename, NULL, bdrv_oflags, false, quiet);
+ blk = img_open(image_opts, filename, NULL, bdrv_oflags, false, quiet,
+ unsafe_read);
if (!blk) {
return 1;
}
@@ -2970,6 +3020,7 @@ static int img_rebase(int argc, char **argv)
int c, flags, src_flags, ret;
bool writethrough, src_writethrough;
int unsafe = 0;
+ int unsafe_read = 0;
int progress = 0;
bool quiet = false;
Error *local_err = NULL;
@@ -2986,9 +3037,10 @@ static int img_rebase(int argc, char **argv)
{"help", no_argument, 0, 'h'},
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+ {"unsafe-read", no_argument, 0, 'U'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "hf:F:b:upt:T:q",
+ c = getopt_long(argc, argv, "hf:F:b:upt:T:qU",
long_options, NULL);
if (c == -1) {
break;
@@ -3033,6 +3085,9 @@ static int img_rebase(int argc, char **argv)
case OPTION_IMAGE_OPTS:
image_opts = true;
break;
+ case 'U':
+ unsafe_read = 1;
+ break;
}
}
@@ -3081,7 +3136,8 @@ static int img_rebase(int argc, char **argv)
* Ignore the old backing file for unsafe rebase in case we want to correct
* the reference to a renamed or moved backing file.
*/
- blk = img_open(image_opts, filename, fmt, flags, writethrough, quiet);
+ blk = img_open(image_opts, filename, fmt, flags, writethrough, quiet,
+ unsafe_read);
if (!blk) {
ret = -1;
goto out;
@@ -3106,6 +3162,9 @@ static int img_rebase(int argc, char **argv)
qdict_put(options, "driver", qstring_from_str(bs->backing_format));
}
+ if (unsafe_read) {
+ src_flags |= BDRV_O_UNSAFE_READ;
+ }
bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name));
blk_old_backing = blk_new_open(backing_name, NULL,
options, src_flags, &local_err);
@@ -3321,6 +3380,7 @@ static int img_resize(int argc, char **argv)
bool quiet = false;
BlockBackend *blk = NULL;
QemuOpts *param;
+ bool unsafe_read = true;
static QemuOptsList resize_options = {
.name = "resize_options",
@@ -3353,9 +3413,10 @@ static int img_resize(int argc, char **argv)
{"help", no_argument, 0, 'h'},
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+ {"unsafe-read", no_argument, 0, 'U'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "f:hq",
+ c = getopt_long(argc, argv, "f:hqU",
long_options, NULL);
if (c == -1) {
break;
@@ -3371,6 +3432,9 @@ static int img_resize(int argc, char **argv)
case 'q':
quiet = true;
break;
+ case 'U':
+ unsafe_read = true;
+ break;
case OPTION_OBJECT: {
QemuOpts *opts;
opts = qemu_opts_parse_noisily(&qemu_object_opts,
@@ -3423,7 +3487,8 @@ static int img_resize(int argc, char **argv)
qemu_opts_del(param);
blk = img_open(image_opts, filename, fmt,
- BDRV_O_RDWR | BDRV_O_RESIZE, false, quiet);
+ BDRV_O_RDWR | BDRV_O_RESIZE, false, quiet,
+ unsafe_read);
if (!blk) {
ret = -1;
goto out;
@@ -3484,6 +3549,7 @@ static int img_amend(int argc, char **argv)
BlockBackend *blk = NULL;
BlockDriverState *bs = NULL;
bool image_opts = false;
+ bool unsafe_read = false;
cache = BDRV_DEFAULT_CACHE;
for (;;) {
@@ -3491,9 +3557,10 @@ static int img_amend(int argc, char **argv)
{"help", no_argument, 0, 'h'},
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+ {"unsafe-read", no_argument, 0, 'U'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "ho:f:t:pq",
+ c = getopt_long(argc, argv, "ho:f:t:pqU",
long_options, NULL);
if (c == -1) {
break;
@@ -3581,7 +3648,8 @@ static int img_amend(int argc, char **argv)
goto out;
}
- blk = img_open(image_opts, filename, fmt, flags, writethrough, quiet);
+ blk = img_open(image_opts, filename, fmt, flags, writethrough, quiet,
+ unsafe_read);
if (!blk) {
ret = -1;
goto out;
@@ -3749,6 +3817,7 @@ static int img_bench(int argc, char **argv)
bool writethrough = false;
struct timeval t1, t2;
int i;
+ bool unsafe_read = false;
for (;;) {
static const struct option long_options[] = {
@@ -3757,9 +3826,10 @@ static int img_bench(int argc, char **argv)
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
{"pattern", required_argument, 0, OPTION_PATTERN},
{"no-drain", no_argument, 0, OPTION_NO_DRAIN},
+ {"unsafe-read", no_argument, 0, 'U'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "hc:d:f:no:qs:S:t:w", long_options, NULL);
+ c = getopt_long(argc, argv, "hc:d:f:no:qs:S:t:wU", long_options, NULL);
if (c == -1) {
break;
}
@@ -3848,6 +3918,9 @@ static int img_bench(int argc, char **argv)
flags |= BDRV_O_RDWR;
is_write = true;
break;
+ case 'U':
+ unsafe_read = true;
+ break;
case OPTION_PATTERN:
{
unsigned long res;
@@ -3895,7 +3968,8 @@ static int img_bench(int argc, char **argv)
goto out;
}
- blk = img_open(image_opts, filename, fmt, flags, writethrough, quiet);
+ blk = img_open(image_opts, filename, fmt, flags, writethrough, quiet,
+ unsafe_read);
if (!blk) {
ret = -1;
goto out;
@@ -4062,6 +4136,7 @@ static int img_dd(int argc, char **argv)
const char *fmt = NULL;
int64_t size = 0;
int64_t block_count = 0, out_pos, in_pos;
+ bool unsafe_read = false;
struct DdInfo dd = {
.flags = 0,
.count = 0,
@@ -4090,10 +4165,11 @@ static int img_dd(int argc, char **argv)
const struct option long_options[] = {
{ "help", no_argument, 0, 'h'},
{ "image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+ { "unsafe-read", no_argument, 0, 'U'},
{ 0, 0, 0, 0 }
};
- while ((c = getopt_long(argc, argv, "hf:O:", long_options, NULL))) {
+ while ((c = getopt_long(argc, argv, "hf:O:U", long_options, NULL))) {
if (c == EOF) {
break;
}
@@ -4111,6 +4187,9 @@ static int img_dd(int argc, char **argv)
case 'h':
help();
break;
+ case 'U':
+ unsafe_read = true;
+ break;
case OPTION_IMAGE_OPTS:
image_opts = true;
break;
@@ -4155,7 +4234,8 @@ static int img_dd(int argc, char **argv)
ret = -1;
goto out;
}
- blk1 = img_open(image_opts, in.filename, fmt, 0, false, false);
+ blk1 = img_open(image_opts, in.filename, fmt, 0, false, false,
+ unsafe_read);
if (!blk1) {
ret = -1;
@@ -4223,7 +4303,7 @@ static int img_dd(int argc, char **argv)
}
blk2 = img_open(image_opts, out.filename, out_fmt, BDRV_O_RDWR,
- false, false);
+ false, false, unsafe_read);
if (!blk2) {
ret = -1;
--
2.9.3
next prev parent reply other threads:[~2017-03-14 2:39 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-14 2:39 [Qemu-devel] [PATCH RFC 0/3] block: Backdoor to skip image locking in qemu-io/qemu-img Fam Zheng
2017-03-14 2:39 ` [Qemu-devel] [PATCH RFC 1/3] block: Introduce BDRV_O_UNSAFE_READ Fam Zheng
2017-04-18 13:15 ` Eric Blake
2017-03-14 2:39 ` Fam Zheng [this message]
2017-04-18 13:20 ` [Qemu-devel] [PATCH RFC 2/3] qemu-img: Add --unsafe-read option to subcommands Eric Blake
2017-04-20 3:27 ` Fam Zheng
2017-03-14 2:39 ` [Qemu-devel] [PATCH RFC 3/3] qemu-io: Add --unsafe-read option Fam Zheng
2017-04-18 13:27 ` Eric Blake
2017-04-20 3:29 ` Fam Zheng
2017-04-14 1:14 ` [Qemu-devel] [Qemu-block] [PATCH RFC 0/3] block: Backdoor to skip image locking in qemu-io/qemu-img John Snow
2017-04-14 2:25 ` Fam Zheng
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