The current code in libxl assumed that vdev is equal to local device, but
this is only true for Linux systems. In other OSes the local device can use
a nomenclature completely different from the virtual device one.
Move the current libxl__devid_to_localdev Linux implementation out of the
OS-specific file and rename it to libxl__devid_to_vdev, and then make sure
local_device_attach_cb return the local device in the diskpath field.
Signed-off-by: Roger Pau Monné <roger....@citrix.com>
---
Cc: Ian Jackson <ian.jack...@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabell...@eu.citrix.com>
Cc: Ian Campbell <ian.campb...@citrix.com>
Cc: Wei Liu <wei.l...@citrix.com>
---
tools/libxl/libxl.c | 12 ++++------
tools/libxl/libxl_device.c | 57 ++++++++++++++++++++++++++++++++++++++++++++
tools/libxl/libxl_internal.h | 1 +
tools/libxl/libxl_linux.c | 49 +------------------------------------
4 files changed, 64 insertions(+), 55 deletions(-)
diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
index 6d719d7..d55c699 100644
--- a/tools/libxl/libxl.c
+++ b/tools/libxl/libxl.c
@@ -3071,7 +3071,7 @@ static char * libxl__alloc_vdev(libxl__gc *gc, void
*get_vdev_user,
GCSPRINTF("%s/device/vbd/%d/backend",
dompath, devid)) == NULL) {
if (errno == ENOENT)
- return libxl__devid_to_localdev(gc, devid);
+ return libxl__devid_to_vdev(gc, devid);
else
return NULL;
}
@@ -3137,7 +3137,7 @@ static void local_device_attach_cb(libxl__egc *egc,
libxl__ao_device *aodev)
{
STATE_AO_GC(aodev->ao);
libxl__disk_local_state *dls = CONTAINER_OF(aodev, *dls, aodev);
- char *dev = NULL, *be_path = NULL;
+ char *be_path = NULL;
int rc;
libxl__device device;
libxl_device_disk *disk = &dls->disk;
@@ -3151,9 +3151,6 @@ static void local_device_attach_cb(libxl__egc *egc,
libxl__ao_device *aodev)
goto out;
}
- dev = GCSPRINTF("/dev/%s", disk->vdev);
- LOG(DEBUG, "locally attaching disk %s", dev);
-
rc = libxl__device_from_disk(gc, LIBXL_TOOLSTACK_DOMID, disk, &device);
if (rc < 0)
goto out;
@@ -3162,8 +3159,9 @@ static void local_device_attach_cb(libxl__egc *egc,
libxl__ao_device *aodev)
if (rc < 0)
goto out;
- if (dev != NULL)
- dls->diskpath = libxl__strdup(gc, dev);
+ dls->diskpath = GCSPRINTF("/dev/%s",
+ libxl__devid_to_localdev(gc, device.devid));
+ LOG(DEBUG, "locally attached disk %s", dls->diskpath);
dls->callback(egc, dls, 0);
return;
diff --git a/tools/libxl/libxl_device.c b/tools/libxl/libxl_device.c
index 8bb5e93..f5b8bf6 100644
--- a/tools/libxl/libxl_device.c
+++ b/tools/libxl/libxl_device.c
@@ -436,6 +436,63 @@ int libxl__device_disk_dev_number(const char *virtpath,
int *pdisk,
return -1;
}
+static char *encode_disk_name(char *ptr, unsigned int n)
+{
+ if (n >= 26)
+ ptr = encode_disk_name(ptr, n / 26 - 1);
+ *ptr = 'a' + n % 26;
+ return ptr + 1;
+}
+
+char *libxl__devid_to_vdev(libxl__gc *gc, int devid)
+{
+ unsigned int minor;
+ int offset;
+ int nr_parts;
+ char *ptr = NULL;
+/* Same as in Linux.
+ * encode_disk_name might end up using up to 29 bytes (BUFFER_SIZE - 3)
+ * including the trailing \0.
+ *
+ * The code is safe because 26 raised to the power of 28 (that is the
+ * maximum offset that can be stored in the allocated buffer as a
+ * string) is far greater than UINT_MAX on 64 bits so offset cannot be
+ * big enough to exhaust the available bytes in ret. */
+#define BUFFER_SIZE 32
+ char *ret = libxl__zalloc(gc, BUFFER_SIZE);
+
+#define EXT_SHIFT 28
+#define EXTENDED (1<<EXT_SHIFT)
+#define VDEV_IS_EXTENDED(dev) ((dev)&(EXTENDED))
+#define BLKIF_MINOR_EXT(dev) ((dev)&(~EXTENDED))
+/* the size of the buffer to store the device name is 32 bytes to match the
+ * equivalent buffer in the Linux kernel code */
+
+ if (!VDEV_IS_EXTENDED(devid)) {
+ minor = devid & 0xff;
+ nr_parts = 16;
+ } else {
+ minor = BLKIF_MINOR_EXT(devid);
+ nr_parts = 256;
+ }
+ offset = minor / nr_parts;
+
+ strcpy(ret, "xvd");
+ ptr = encode_disk_name(ret + 3, offset);
+ if (minor % nr_parts == 0)
+ *ptr = 0;
+ else
+ /* overflow cannot happen, thanks to the upper bound */
+ snprintf(ptr, ret + 32 - ptr,
+ "%d", minor & (nr_parts - 1));
+ return ret;
+#undef BUFFER_SIZE
+#undef EXT_SHIFT
+#undef EXTENDED
+#undef VDEV_IS_EXTENDED
+#undef BLKIF_MINOR_EXT
+}
+
/* Device AO operations */
void libxl__prepare_ao_device(libxl__ao *ao, libxl__ao_device *aodev)
diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
index 1a3fa35..4d1c51f 100644
--- a/tools/libxl/libxl_internal.h
+++ b/tools/libxl/libxl_internal.h
@@ -1156,6 +1156,7 @@ _hidden int libxl__device_disk_set_backend(libxl__gc*,
libxl_device_disk*);
_hidden int libxl__device_physdisk_major_minor(const char *physpath, int
*major, int *minor);
_hidden int libxl__device_disk_dev_number(const char *virtpath,
int *pdisk, int *ppartition);
+_hidden char *libxl__devid_to_vdev(libxl__gc *gc, int devid);
_hidden int libxl__device_console_add(libxl__gc *gc, uint32_t domid,
libxl__device_console *console,
diff --git a/tools/libxl/libxl_linux.c b/tools/libxl/libxl_linux.c
index 7e6d7b9..8073aec 100644
--- a/tools/libxl/libxl_linux.c
+++ b/tools/libxl/libxl_linux.c
@@ -26,56 +26,9 @@ int libxl__try_phy_backend(mode_t st_mode)
return 0;
}
-#define EXT_SHIFT 28
-#define EXTENDED (1<<EXT_SHIFT)
-#define VDEV_IS_EXTENDED(dev) ((dev)&(EXTENDED))
-#define BLKIF_MINOR_EXT(dev) ((dev)&(~EXTENDED))
-/* the size of the buffer to store the device name is 32 bytes to match the
- * equivalent buffer in the Linux kernel code */
-#define BUFFER_SIZE 32
-
-/* Same as in Linux.
- * encode_disk_name might end up using up to 29 bytes (BUFFER_SIZE - 3)
- * including the trailing \0.
- *
- * The code is safe because 26 raised to the power of 28 (that is the
- * maximum offset that can be stored in the allocated buffer as a
- * string) is far greater than UINT_MAX on 64 bits so offset cannot be
- * big enough to exhaust the available bytes in ret. */
-static char *encode_disk_name(char *ptr, unsigned int n)
-{
- if (n >= 26)
- ptr = encode_disk_name(ptr, n / 26 - 1);
- *ptr = 'a' + n % 26;
- return ptr + 1;
-}
-
char *libxl__devid_to_localdev(libxl__gc *gc, int devid)
{
- unsigned int minor;
- int offset;
- int nr_parts;
- char *ptr = NULL;
- char *ret = libxl__zalloc(gc, BUFFER_SIZE);
-
- if (!VDEV_IS_EXTENDED(devid)) {
- minor = devid & 0xff;
- nr_parts = 16;
- } else {
- minor = BLKIF_MINOR_EXT(devid);
- nr_parts = 256;
- }
- offset = minor / nr_parts;
-
- strcpy(ret, "xvd");
- ptr = encode_disk_name(ret + 3, offset);
- if (minor % nr_parts == 0)
- *ptr = 0;
- else
- /* overflow cannot happen, thanks to the upper bound */
- snprintf(ptr, ret + 32 - ptr,
- "%d", minor & (nr_parts - 1));
- return ret;
+ return libxl__devid_to_vdev(gc, devid);
}
/* Hotplug scripts helpers */
--
2.5.4 (Apple Git-61)
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