[BLKTAP] Use lartge enough types to express parameters of large block devices.

While the kernel side of blktap drivers is using 64-bit sector numbers
correctly when reporting disk sizing, the userspace parts where this
dat is actually generated is truncating at 32-bit. There are 3 variables
related to disk sizing which are used in the kernel/userspace code
'size', 'sector size' & 'info'. In kernel space these are treated as being
unsigned long long, unsigned long, and unsigned int, respectively. In
the blktap userspace code this were all varyingly long, unsigned long.
This mismatch caused 32-bit wraparound on large disks. The attached
patch updates the blktap userspace to use the same data types as
kernel space for all these params, thus both fixing the 32-bit bug &
giving the code consistency.

This patch has been tested both by comparing /proc/partitions in the
guest, with the image size seen in the host, and by using Stephen
Tweedie's 'verify-data' tool on a variety of multi-TB sized disks.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

diff --git a/tools/blktap/drivers/blktapctrl.c b/tools/blktap/drivers/blktapctrl.c
index 2a2c8769bbb33320b308a0ba4ede519e54cab68d..cb2258af42f5ed0305af43535815e3a94d974ce7 100644 (file)
--- a/tools/blktap/drivers/blktapctrl.c
+++ b/tools/blktap/drivers/blktapctrl.c
@@ -420,7 +420,7 @@ static int read_msg(int fd, int msgtype, void *ptr)
                        image->secsize = img->secsize;
                        image->info = img->info;
 
-                       DPRINTF("Received CTLMSG_IMG: %lu, %lu, %lu\n",
+                       DPRINTF("Received CTLMSG_IMG: %llu, %lu, %u\n",
                                image->size, image->secsize, image->info);
                        if(msgtype != CTLMSG_IMG) ret = 0;
                        break;

diff --git a/tools/blktap/drivers/blktapctrl.h b/tools/blktap/drivers/blktapctrl.h
index 4a5e59577ed39d952bab0e412b27634e91744a98..ddcb967533412b64abbbedc9ae74e8aa3f15e91f 100644 (file)
--- a/tools/blktap/drivers/blktapctrl.h
+++ b/tools/blktap/drivers/blktapctrl.h
@@ -30,19 +30,19 @@
  */
 
 
-static inline long int tapdisk_get_size(blkif_t *blkif)
+static inline unsigned long long tapdisk_get_size(blkif_t *blkif)
 {
        image_t *img = (image_t *)blkif->prv;
        return img->size;
 }
 
-static inline long int tapdisk_get_secsize(blkif_t *blkif)
+static inline unsigned long tapdisk_get_secsize(blkif_t *blkif)
 {
        image_t *img = (image_t *)blkif->prv;
        return img->secsize;
 }
 
-static inline unsigned tapdisk_get_info(blkif_t *blkif)
+static inline unsigned int tapdisk_get_info(blkif_t *blkif)
 {
        image_t *img = (image_t *)blkif->prv;
        return img->info;

diff --git a/tools/blktap/drivers/tapdisk.h b/tools/blktap/drivers/tapdisk.h
index 2455b5282e4d73e344d00e503f0b56fdb6fd4d3c..813c05ebe3335868c117bf5b2ee11f8ca317467d 100644 (file)
--- a/tools/blktap/drivers/tapdisk.h
+++ b/tools/blktap/drivers/tapdisk.h
@@ -74,9 +74,9 @@ struct td_state {
        void *ring_info;
        void *fd_entry;
        char backing_file[1024]; /*Used by differencing disks, e.g. qcow*/
-       long int   sector_size;
-       uint64_t   size;
-       long int   info;
+       unsigned long      sector_size;
+       unsigned long long size;
+       unsigned int       info;
 };
 
 /* Prototype of the callback to activate as requests complete.              */

diff --git a/tools/blktap/lib/blktaplib.h b/tools/blktap/lib/blktaplib.h
index 456497a608530c6ad11899f262c88b5b373039b8..12f4950133f61b496c5329e5a378faf56f667043 100644 (file)
--- a/tools/blktap/lib/blktaplib.h
+++ b/tools/blktap/lib/blktaplib.h
@@ -97,9 +97,9 @@ typedef struct {
 } pending_req_t;
 
 struct blkif_ops {
-       long int (*get_size)(struct blkif *blkif);
-       long int (*get_secsize)(struct blkif *blkif);
-       unsigned (*get_info)(struct blkif *blkif);
+       unsigned long long (*get_size)(struct blkif *blkif);
+       unsigned long (*get_secsize)(struct blkif *blkif);
+       unsigned int (*get_info)(struct blkif *blkif);
 };
 
 typedef struct blkif {
@@ -156,9 +156,9 @@ typedef struct domid_translate {
 } domid_translate_t ;
 
 typedef struct image {
-       long int size;
-       long int secsize;
-       long int info;
+       unsigned long long size;
+       unsigned long secsize;
+       unsigned int info;
 } image_t;
 
 typedef struct msg_hdr {

diff --git a/tools/blktap/lib/xenbus.c b/tools/blktap/lib/xenbus.c
index ea7377d47cb9e07c7aefb696d60e922747855346..d50e492784bc14f1751b2ac295bf35505123eb1c 100644 (file)
--- a/tools/blktap/lib/xenbus.c
+++ b/tools/blktap/lib/xenbus.c
@@ -219,7 +219,7 @@ static void ueblktap_setup(struct xs_handle *h, char *bepath)
        }
 
        /* Supply the information about the device to xenstore */
-       er = xs_printf(h, be->backpath, "sectors", "%lu",
+       er = xs_printf(h, be->backpath, "sectors", "%llu",
                        be->blkif->ops->get_size(be->blkif));
 
        if (er == 0) {