Patchwork [v2] block: allow resizing of images residing on host devices

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Submitter Christoph Hellwig
Date Sept. 20, 2011, 11:10 p.m.
Message ID <20110920231037.GA1872@lst.de>
Download mbox | patch
Permalink /patch/115644/
State New
Headers show

Comments

Christoph Hellwig - Sept. 20, 2011, 11:10 p.m.
Allow to resize images that reside on host devices up to the available
space.  This allows to grow images after resizing the device manually or
vice versa.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Kevin Wolf - Sept. 21, 2011, 2:23 p.m.
Am 21.09.2011 01:10, schrieb Christoph Hellwig:
> Allow to resize images that reside on host devices up to the available
> space.  This allows to grow images after resizing the device manually or
> vice versa.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Thanks, applied to the block branch.

Kevin

Patch

Index: qemu/block/raw-posix.c
===================================================================
--- qemu.orig/block/raw-posix.c	2011-09-20 13:56:02.422662877 -0400
+++ qemu/block/raw-posix.c	2011-09-20 18:56:23.647165015 -0400
@@ -649,10 +649,24 @@  static void raw_close(BlockDriverState *
 static int raw_truncate(BlockDriverState *bs, int64_t offset)
 {
     BDRVRawState *s = bs->opaque;
-    if (s->type != FTYPE_FILE)
-        return -ENOTSUP;
-    if (ftruncate(s->fd, offset) < 0)
+    struct stat st;
+
+    if (fstat(s->fd, &st)) {
         return -errno;
+    }
+
+    if (S_ISREG(st.st_mode)) {
+        if (ftruncate(s->fd, offset) < 0) {
+            return -errno;
+        }
+    } else if (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode)) {
+       if (offset > raw_getlength(bs)) {
+           return -EINVAL;
+       }
+    } else {
+        return -ENOTSUP;
+    }
+
     return 0;
 }
 
@@ -1171,6 +1185,7 @@  static BlockDriver bdrv_host_device = {
 
     .bdrv_read          = raw_read,
     .bdrv_write         = raw_write,
+    .bdrv_truncate = raw_truncate,
     .bdrv_getlength	= raw_getlength,
     .bdrv_get_allocated_file_size
                         = raw_get_allocated_file_size,
@@ -1292,6 +1307,7 @@  static BlockDriver bdrv_host_floppy = {
 
     .bdrv_read          = raw_read,
     .bdrv_write         = raw_write,
+    .bdrv_truncate = raw_truncate,
     .bdrv_getlength	= raw_getlength,
     .bdrv_get_allocated_file_size
                         = raw_get_allocated_file_size,
@@ -1393,6 +1409,7 @@  static BlockDriver bdrv_host_cdrom = {
 
     .bdrv_read          = raw_read,
     .bdrv_write         = raw_write,
+    .bdrv_truncate = raw_truncate,
     .bdrv_getlength     = raw_getlength,
     .bdrv_get_allocated_file_size
                         = raw_get_allocated_file_size,
@@ -1514,6 +1531,7 @@  static BlockDriver bdrv_host_cdrom = {
 
     .bdrv_read          = raw_read,
     .bdrv_write         = raw_write,
+    .bdrv_truncate = raw_truncate,
     .bdrv_getlength     = raw_getlength,
     .bdrv_get_allocated_file_size
                         = raw_get_allocated_file_size,