[Qemu-devel] [PATCH] ioemu: fix flags in bdrv_open2

[Wei Kong]

this patch against for qemu-0.10.5, it's also for xen unstable.

---
If BDRV_O_FILE not set in flags, it doesn't means O_RDWR, the O_RDONLY in flags should be useful.

Signed-off-by: Wei Kong <weikong.cn@gmail.com>

diff -uNrp qemu-0.10.5/block.c qemu-0.10.5.new/block.c
--- qemu-0.10.5/block.c 2009-05-21 04:46:58.000000000 +0800
+++ qemu-0.10.5.new/block.c     2009-06-01 10:30:42.000000000 +0800
@@ -393,12 +393,13 @@ int bdrv_open2(BlockDriverState *bs, con

     }
     bs->drv = drv;
     bs->opaque = qemu_mallocz(drv->instance_size);
-    /* Note: for compatibility, we open disk image files as RDWR, and
-       RDONLY as fallback */
     if (!(flags & BDRV_O_FILE))

-        open_flags = BDRV_O_RDWR | (flags & BDRV_O_CACHE_MASK);
+        open_flags = flags & BDRV_O_CACHE_MASK;
     else
         open_flags = flags & ~(BDRV_O_FILE | BDRV_O_SNAPSHOT);
+    if (!(open_flags & BDRV_O_RDWR))

+        bs->read_only = 1;
+
     ret = drv->bdrv_open(bs, filename, open_flags);
     if ((ret == -EACCES || ret == -EPERM) && !(flags & BDRV_O_FILE)) {
         ret = drv->bdrv_open(bs, filename, open_flags & ~BDRV_O_RDWR);

diff -uNrp qemu-0.10.5/hw/usb-msd.c qemu-0.10.5.new/hw/usb-msd.c
--- qemu-0.10.5/hw/usb-msd.c    2009-05-21 04:46:59.000000000 +0800
+++ qemu-0.10.5.new/hw/usb-msd.c        2009-06-01 10:14:17.000000000 +0800
@@ -551,7 +551,7 @@ USBDevice *usb_msd_init(const char *file

     s = qemu_mallocz(sizeof(MSDState));

     bdrv = bdrv_new("usb");
-    if (bdrv_open2(bdrv, filename, 0, drv) < 0)
+    if (bdrv_open2(bdrv, filename, BDRV_O_RDWR, drv) < 0)
         goto fail;

     s->bs = bdrv;
     *pbs = bdrv;
diff -uNrp qemu-0.10.5/qemu-img.c qemu-0.10.5.new/qemu-img.c
--- qemu-0.10.5/qemu-img.c      2009-05-21 04:47:00.000000000 +0800
+++ qemu-0.10.5.new/qemu-img.c  2009-06-01 10:28:46.000000000 +0800

@@ -32,7 +32,7 @@
 #endif

 /* Default to cache=writeback as data integrity is not important for qemu-tcg. */
-#define BRDV_O_FLAGS BDRV_O_CACHE_WB
+#define BDRV_O_FLAGS BDRV_O_CACHE_WB

 static void QEMU_NORETURN error(const char *fmt, ...)

 {
@@ -185,7 +185,7 @@ static int read_password(char *buf, int
 #endif

 static BlockDriverState *bdrv_new_open(const char *filename,
-                                       const char *fmt)
+                                       const char *fmt, int flags)

 {
     BlockDriverState *bs;
     BlockDriver *drv;
@@ -201,7 +201,7 @@ static BlockDriverState *bdrv_new_open(c
     } else {
         drv = NULL;
     }
-    if (bdrv_open2(bs, filename, BRDV_O_FLAGS, drv) < 0) {

+    if (bdrv_open2(bs, filename, flags, drv) < 0) {
         error("Could not open '%s'", filename);
     }
     if (bdrv_is_encrypted(bs)) {
@@ -253,7 +253,7 @@ static int img_create(int argc, char **a

     size = 0;
     if (base_filename) {
         BlockDriverState *bs;
-        bs = bdrv_new_open(base_filename, NULL);
+        bs = bdrv_new_open(base_filename, NULL, BDRV_O_RDWR);
         bdrv_get_geometry(bs, &size);

         size *= 512;
         bdrv_delete(bs);
@@ -334,7 +334,7 @@ static int img_commit(int argc, char **a
     } else {
         drv = NULL;
     }
-    if (bdrv_open2(bs, filename, BRDV_O_FLAGS, drv) < 0) {

+    if (bdrv_open2(bs, filename, BDRV_O_FLAGS|BDRV_O_RDWR, drv) < 0) {
         error("Could not open '%s'", filename);
     }
     ret = bdrv_commit(bs);
@@ -457,7 +457,8 @@ static int img_convert(int argc, char **

     total_sectors = 0;
     for (bs_i = 0; bs_i < bs_n; bs_i++) {
-        bs[bs_i] = bdrv_new_open(argv[optind + bs_i], fmt);
+        bs[bs_i] = bdrv_new_open(argv[optind + bs_i], fmt, 
+                                     BDRV_O_CACHE_WB|BDRV_O_RDONLY);

         if (!bs[bs_i])
             error("Could not open '%s'", argv[optind + bs_i]);
         bdrv_get_geometry(bs[bs_i], &bs_sectors);
@@ -487,7 +488,7 @@ static int img_convert(int argc, char **

         }
     }

-    out_bs = bdrv_new_open(out_filename, out_fmt);
+    out_bs = bdrv_new_open(out_filename, out_fmt, BDRV_O_CACHE_WB|BDRV_O_RDWR);

     bs_i = 0;
     bs_offset = 0;
@@ -710,7 +711,7 @@ static int img_info(int argc, char **arg

     } else {
         drv = NULL;
     }
-    if (bdrv_open2(bs, filename, BRDV_O_FLAGS, drv) < 0) {
+    if (bdrv_open2(bs, filename, BDRV_O_FLAGS|BDRV_O_RDONLY, drv) < 0) {
         error("Could not open '%s'", filename);

     }
     bdrv_get_format(bs, fmt_name, sizeof(fmt_name));
@@ -814,7 +815,7 @@ static void img_snapshot(int argc, char
     if (!bs)
         error("Not enough memory");

-    if (bdrv_open2(bs, filename, 0, NULL) < 0) {

+    if (bdrv_open2(bs, filename, BDRV_O_RDWR, NULL) < 0) {
         error("Could not open '%s'", filename);
     }