@@ -310,7 +310,7 @@ static BlockDriver *find_image_format(const char *filename)
if (drv && strcmp(drv->format_name, "vvfat") == 0)
return drv;
- ret = bdrv_file_open(&bs, filename, BDRV_O_RDONLY);
+ ret = bdrv_file_open(&bs, filename, ~BDRV_O_RDWR);
if (ret < 0)
return NULL;
ret = bdrv_pread(bs, 0, buf, sizeof(buf));
@@ -356,7 +356,7 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags)
int bdrv_open2(BlockDriverState *bs, const char *filename, int flags,
BlockDriver *drv)
{
- int ret, open_flags, try_rw;
+ int ret, open_flags;
char tmp_filename[PATH_MAX];
char backing_filename[PATH_MAX];
@@ -378,7 +378,7 @@ int bdrv_open2(BlockDriverState *bs, const char *filename, int flags,
/* if there is a backing file, use it */
bs1 = bdrv_new("");
- ret = bdrv_open2(bs1, filename, 0, drv);
+ ret = bdrv_open2(bs1, filename, ~BDRV_O_RDWR, drv);
if (ret < 0) {
bdrv_delete(bs1);
return ret;
@@ -445,18 +445,22 @@ int bdrv_open2(BlockDriverState *bs, const char *filename, int flags,
bs->enable_write_cache = 1;
/* Note: for compatibility, we open disk image files as RDWR, and
- RDONLY as fallback */
- try_rw = !bs->read_only || bs->is_temporary;
- if (!(flags & BDRV_O_FILE))
- open_flags = (try_rw ? BDRV_O_RDWR : 0) |
- (flags & (BDRV_O_CACHE_MASK|BDRV_O_NATIVE_AIO));
- else
+ RDONLY as fallback (if flag BDRV_O_RO_FALLBACK is on) */
+ bs->read_only = BDRV_FLAGS_IS_RO(flags);
+ if (!(flags & BDRV_O_FILE)) {
+ open_flags = (flags & (BDRV_O_RDWR | BDRV_O_CACHE_MASK|BDRV_O_NATIVE_AIO));
+ if (bs->is_temporary) { /* snapshot */
+ open_flags |= BDRV_O_RDWR;
+ }
+ } else {
open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT);
+ }
if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv))
ret = -ENOTSUP;
else
ret = drv->bdrv_open(bs, filename, open_flags);
- if ((ret == -EACCES || ret == -EPERM) && !(flags & BDRV_O_FILE)) {
+ if ((ret == -EACCES || ret == -EPERM) && !(flags & BDRV_O_FILE) &&
+ (flags & BDRV_O_RO_FALLBACK)) {
ret = drv->bdrv_open(bs, filename, open_flags & ~BDRV_O_RDWR);
bs->read_only = 1;
}
@@ -481,14 +485,13 @@ int bdrv_open2(BlockDriverState *bs, const char *filename, int flags,
/* if there is a backing file, use it */
BlockDriver *back_drv = NULL;
bs->backing_hd = bdrv_new("");
- /* pass on read_only property to the backing_hd */
- bs->backing_hd->read_only = bs->read_only;
path_combine(backing_filename, sizeof(backing_filename),
filename, bs->backing_file);
if (bs->backing_format[0] != '\0')
back_drv = bdrv_find_format(bs->backing_format);
ret = bdrv_open2(bs->backing_hd, backing_filename, open_flags,
back_drv);
+ bs->backing_hd->read_only = BDRV_FLAGS_IS_RO(open_flags);
if (ret < 0) {
bdrv_close(bs);
return ret;
@@ -28,8 +28,8 @@ typedef struct QEMUSnapshotInfo {
} QEMUSnapshotInfo;
#define BDRV_O_RDONLY 0x0000
-#define BDRV_O_RDWR 0x0002
-#define BDRV_O_ACCESS 0x0003
+#define BDRV_O_RDWR 0x0001
+#define BDRV_O_RO_FALLBACK 0x0002
#define BDRV_O_CREAT 0x0004 /* create an empty file */
#define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */
#define BDRV_O_FILE 0x0010 /* open as a raw file (do not try to
@@ -41,6 +41,8 @@ typedef struct QEMUSnapshotInfo {
#define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */
#define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_CACHE_WB)
+#define BDRV_O_DEFAULT_OPEN (BDRV_O_RDWR | BDRV_O_RO_FALLBACK)
+#define BDRV_FLAGS_IS_RO(flags) ((flags & BDRV_O_RDWR) == 0)
#define BDRV_SECTOR_BITS 9
#define BDRV_SECTOR_SIZE (1 << BDRV_SECTOR_BITS)
@@ -138,7 +138,7 @@ static int raw_open_common(BlockDriverState *bs, const char *filename,
s->open_flags = open_flags | O_BINARY;
s->open_flags &= ~O_ACCMODE;
- if ((bdrv_flags & BDRV_O_ACCESS) == BDRV_O_RDWR) {
+ if (bdrv_flags & BDRV_O_RDWR) {
s->open_flags |= O_RDWR;
} else {
s->open_flags |= O_RDONLY;
@@ -81,7 +81,7 @@ static int raw_open(BlockDriverState *bs, const char *filename, int flags)
s->type = FTYPE_FILE;
- if ((flags & BDRV_O_ACCESS) == O_RDWR) {
+ if (flags & BDRV_O_RDWR) {
access_flags = GENERIC_READ | GENERIC_WRITE;
} else {
access_flags = GENERIC_READ;
@@ -337,7 +337,7 @@ static int hdev_open(BlockDriverState *bs, const char *filename, int flags)
}
s->type = find_device_type(bs, filename);
- if ((flags & BDRV_O_ACCESS) == O_RDWR) {
+ if (flags & BDRV_O_RDWR) {
access_flags = GENERIC_READ | GENERIC_WRITE;
} else {
access_flags = GENERIC_READ;
@@ -357,7 +357,7 @@ static int vmdk_parent_open(BlockDriverState *bs, const char * filename)
return -1;
}
parent_open = 1;
- if (bdrv_open(bs->backing_hd, parent_img_name, BDRV_O_RDONLY) < 0)
+ if (bdrv_open(bs->backing_hd, parent_img_name, ~BDRV_O_RDWR) < 0)
goto failure;
parent_open = 0;
}
@@ -373,7 +373,7 @@ static int vmdk_open(BlockDriverState *bs, const char *filename, int flags)
if (parent_open)
// Parent must be opened as RO.
- flags = BDRV_O_RDONLY;
+ flags = ~BDRV_O_RDWR;
ret = bdrv_file_open(&s->hd, filename, flags);
if (ret < 0)
@@ -610,10 +610,11 @@ static int blk_init(struct XenDevice *xendev)
/* read-only ? */
if (strcmp(blkdev->mode, "w") == 0) {
mode = O_RDWR;
- qflags = BDRV_O_RDWR;
+ /* for compatibility, also allow readonly fallback, for now */
+ qflags = BDRV_O_RDWR | BDRV_O_RO_FALLBACK;
} else {
mode = O_RDONLY;
- qflags = BDRV_O_RDONLY;
+ qflags = ~BDRV_O_RDWR;
info |= VDISK_READONLY;
}
@@ -915,7 +915,7 @@ static void do_change_block(Monitor *mon, const char *device,
}
if (eject_device(mon, bs, 0) < 0)
return;
- bdrv_open2(bs, filename, 0, drv);
+ bdrv_open2(bs, filename, BDRV_O_DEFAULT_OPEN, drv);
monitor_read_bdrv_key_start(mon, bs, NULL, NULL);
}
@@ -76,8 +76,8 @@ QemuOptsList qemu_drive_opts = {
.type = QEMU_OPT_STRING,
.help = "pci address (virtio only)",
},{
- .name = "readonly",
- .type = QEMU_OPT_BOOL,
+ .name = "access",
+ .type = QEMU_OPT_STRING,
},
{ /* end if list */ }
},
@@ -201,7 +201,7 @@ static BlockDriverState *bdrv_new_open(const char *filename,
} else {
drv = NULL;
}
- if (bdrv_open2(bs, filename, BRDV_O_FLAGS, drv) < 0) {
+ if (bdrv_open2(bs, filename, BRDV_O_FLAGS | BDRV_O_DEFAULT_OPEN, drv) < 0) {
error("Could not open '%s'", filename);
}
if (bdrv_is_encrypted(bs)) {
@@ -406,7 +406,7 @@ static int img_check(int argc, char **argv)
} else {
drv = NULL;
}
- if (bdrv_open2(bs, filename, BRDV_O_FLAGS, drv) < 0) {
+ if (bdrv_open2(bs, filename, BRDV_O_FLAGS & ~BDRV_O_RDWR, drv) < 0) {
error("Could not open '%s'", filename);
}
ret = bdrv_check(bs);
@@ -465,7 +465,7 @@ static int img_commit(int argc, char **argv)
} else {
drv = NULL;
}
- if (bdrv_open2(bs, filename, BRDV_O_FLAGS, drv) < 0) {
+ if (bdrv_open2(bs, filename, BRDV_O_FLAGS | BDRV_O_RDWR, drv) < 0) {
error("Could not open '%s'", filename);
}
ret = bdrv_commit(bs);
@@ -884,7 +884,7 @@ static int img_info(int argc, char **argv)
} else {
drv = NULL;
}
- if (bdrv_open2(bs, filename, BRDV_O_FLAGS, drv) < 0) {
+ if (bdrv_open2(bs, filename, BRDV_O_FLAGS & ~BDRV_O_RDWR, drv) < 0) {
error("Could not open '%s'", filename);
}
bdrv_get_format(bs, fmt_name, sizeof(fmt_name));
@@ -932,10 +932,11 @@ static int img_snapshot(int argc, char **argv)
BlockDriverState *bs;
QEMUSnapshotInfo sn;
char *filename, *snapshot_name = NULL;
- int c, ret;
+ int c, ret, bdrv_oflags;
int action = 0;
qemu_timeval tv;
+ bdrv_oflags = BDRV_O_RDWR; /* but no read-only fallback */
/* Parse commandline parameters */
for(;;) {
c = getopt(argc, argv, "la:c:d:h");
@@ -951,6 +952,7 @@ static int img_snapshot(int argc, char **argv)
return 0;
}
action = SNAPSHOT_LIST;
+ bdrv_oflags = ~BDRV_O_RDWR; /* no need for RW */
break;
case 'a':
if (action) {
@@ -988,7 +990,7 @@ static int img_snapshot(int argc, char **argv)
if (!bs)
error("Not enough memory");
- if (bdrv_open2(bs, filename, 0, NULL) < 0) {
+ if (bdrv_open2(bs, filename, bdrv_oflags, NULL) < 0) {
error("Could not open '%s'", filename);
}
@@ -213,7 +213,7 @@ int main(int argc, char **argv)
int opt_ind = 0;
int li;
char *end;
- int flags = 0;
+ int flags = BDRV_O_DEFAULT_OPEN;
int partition = -1;
int ret;
int shared = 1;
@@ -103,7 +103,7 @@ DEF("drive", HAS_ARG, QEMU_OPTION_drive,
"-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
" [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
" [,cache=writethrough|writeback|none][,format=f][,serial=s]\n"
- " [,addr=A][,id=name][,aio=threads|native]\n"
+ " [,addr=A][,id=name][,aio=threads|native][,access=rw|ro|auto]\n"
" use 'file' as a drive image\n")
DEF("set", HAS_ARG, QEMU_OPTION_set,
"-set group.id.arg=value\n"
@@ -2090,6 +2090,7 @@ DriveInfo *drive_init(QemuOpts *opts, void *opaque,
int *fatal_error)
{
const char *buf;
+ const char *access_buf = 0;
const char *file = NULL;
char devname[128];
const char *serial;
@@ -2104,12 +2105,12 @@ DriveInfo *drive_init(QemuOpts *opts, void *opaque,
int index;
int cache;
int aio = 0;
- int ro = 0;
int bdrv_flags;
int on_read_error, on_write_error;
const char *devaddr;
DriveInfo *dinfo;
int snapshot = 0;
+ int read_write, ro_fallback;
*fatal_error = 1;
@@ -2137,7 +2138,6 @@ DriveInfo *drive_init(QemuOpts *opts, void *opaque,
secs = qemu_opt_get_number(opts, "secs", 0);
snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
- ro = qemu_opt_get_bool(opts, "readonly", 0);
file = qemu_opt_get(opts, "file");
serial = qemu_opt_get(opts, "serial");
@@ -2420,6 +2420,31 @@ DriveInfo *drive_init(QemuOpts *opts, void *opaque,
*fatal_error = 0;
return NULL;
}
+
+ read_write = 1;
+ ro_fallback = 1;
+ access_buf = qemu_opt_get(opts, "access");
+ if (access_buf) {
+ if (!strcmp(access_buf, "ro")) {
+ read_write = 0;
+ ro_fallback = 0;
+ } else if (!strcmp(access_buf, "rw")) {
+ read_write = 1;
+ ro_fallback = 0;
+ } else if (!strcmp(access_buf, "auto")) { /* default, but keep it explicit */
+ read_write = 1;
+ ro_fallback = 1;
+ } else {
+ fprintf(stderr, "qemu: '%s' invalid 'access' option (valid values: [rw|ro|auto] )\n", access_buf);
+ return NULL;
+ }
+ if (type != IF_SCSI && type != IF_VIRTIO && type != IF_FLOPPY &&
+ ( !strcmp(access_buf, "ro") || !strcmp(access_buf, "auto") )) {
+ fprintf(stderr, "qemu: access=%s flag not supported for drive of this interface\n", access_buf);
+ return NULL;
+ }
+ }
+
bdrv_flags = 0;
if (snapshot) {
bdrv_flags |= BDRV_O_SNAPSHOT;
@@ -2435,17 +2460,22 @@ DriveInfo *drive_init(QemuOpts *opts, void *opaque,
} else {
bdrv_flags &= ~BDRV_O_NATIVE_AIO;
}
+
+ if (read_write) {
+ bdrv_flags |= BDRV_O_RDWR;
+ } else {
+ bdrv_flags &= ~BDRV_O_RDWR;
+ }
- if (ro == 1) {
- if (type == IF_IDE) {
- fprintf(stderr, "qemu: readonly flag not supported for drive with ide interface\n");
- return NULL;
- }
- (void)bdrv_set_read_only(dinfo->bdrv, 1);
+ if (ro_fallback) {
+ bdrv_flags |= BDRV_O_RO_FALLBACK;
+ } else {
+ bdrv_flags &= ~BDRV_O_RO_FALLBACK;
}
+
if (bdrv_open2(dinfo->bdrv, file, bdrv_flags, drv) < 0) {
- fprintf(stderr, "qemu: could not open disk image %s: %s\n",
+ fprintf(stderr, "qemu: could not open disk image %s with requested permission: %s\n",
file, strerror(errno));
return NULL;
}