[Qemu-devel] [PATCH 21/21] block: add bdrv_get_allocated_file_size() operation

[Kevin Wolf <kwolf@redhat.com>]

From: Fam Zheng <famcool@gmail.com>

qemu-img.c wants to count allocated file size of image. Previously it
counts a single bs->file by 'stat' or Window API. As VMDK introduces
multiple file support, the operation becomes format specific with
platform specific meanwhile.

The functions are moved to block/raw-{posix,win32}.c and qemu-img.c calls
bdrv_get_allocated_file_size to count the bs. And also added VMDK code
to count his own extents.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block.c           |   19 +++++++++++++++++++
 block.h           |    1 +
 block/raw-posix.c |   21 +++++++++++++++++++++
 block/raw-win32.c |   29 +++++++++++++++++++++++++++++
 block/vmdk.c      |   24 ++++++++++++++++++++++++
 block_int.h       |    1 +
 qemu-img.c        |   31 +------------------------------
 7 files changed, 96 insertions(+), 30 deletions(-)

diff --git a/block.c b/block.c
index 24a25d5..9549b9e 100644
--- a/block.c
+++ b/block.c
@@ -1147,6 +1147,25 @@ int bdrv_truncate(BlockDriverState *bs, int64_t offset)
 }
 
 /**
+ * Length of a allocated file in bytes. Sparse files are counted by actual
+ * allocated space. Return < 0 if error or unknown.
+ */
+int64_t bdrv_get_allocated_file_size(BlockDriverState *bs)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (drv->bdrv_get_allocated_file_size) {
+        return drv->bdrv_get_allocated_file_size(bs);
+    }
+    if (bs->file) {
+        return bdrv_get_allocated_file_size(bs->file);
+    }
+    return -ENOTSUP;
+}
+
+/**
  * Length of a file in bytes. Return < 0 if error or unknown.
  */
 int64_t bdrv_getlength(BlockDriverState *bs)
diff --git a/block.h b/block.h
index 859d1d9..59cc410 100644
--- a/block.h
+++ b/block.h
@@ -89,6 +89,7 @@ int bdrv_write_sync(BlockDriverState *bs, int64_t sector_num,
     const uint8_t *buf, int nb_sectors);
 int bdrv_truncate(BlockDriverState *bs, int64_t offset);
 int64_t bdrv_getlength(BlockDriverState *bs);
+int64_t bdrv_get_allocated_file_size(BlockDriverState *bs);
 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr);
 void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs);
 int bdrv_commit(BlockDriverState *bs);
diff --git a/block/raw-posix.c b/block/raw-posix.c
index 34b64aa..cd89c83 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -793,6 +793,17 @@ static int64_t raw_getlength(BlockDriverState *bs)
 }
 #endif
 
+static int64_t raw_get_allocated_file_size(BlockDriverState *bs)
+{
+    struct stat st;
+    BDRVRawState *s = bs->opaque;
+
+    if (fstat(s->fd, &st) < 0) {
+        return -errno;
+    }
+    return (int64_t)st.st_blocks * 512;
+}
+
 static int raw_create(const char *filename, QEMUOptionParameter *options)
 {
     int fd;
@@ -888,6 +899,8 @@ static BlockDriver bdrv_file = {
 
     .bdrv_truncate = raw_truncate,
     .bdrv_getlength = raw_getlength,
+    .bdrv_get_allocated_file_size
+                        = raw_get_allocated_file_size,
 
     .create_options = raw_create_options,
 };
@@ -1156,6 +1169,8 @@ static BlockDriver bdrv_host_device = {
     .bdrv_read          = raw_read,
     .bdrv_write         = raw_write,
     .bdrv_getlength	= raw_getlength,
+    .bdrv_get_allocated_file_size
+                        = raw_get_allocated_file_size,
 
     /* generic scsi device */
 #ifdef __linux__
@@ -1277,6 +1292,8 @@ static BlockDriver bdrv_host_floppy = {
     .bdrv_read          = raw_read,
     .bdrv_write         = raw_write,
     .bdrv_getlength	= raw_getlength,
+    .bdrv_get_allocated_file_size
+                        = raw_get_allocated_file_size,
 
     /* removable device support */
     .bdrv_is_inserted   = floppy_is_inserted,
@@ -1380,6 +1397,8 @@ static BlockDriver bdrv_host_cdrom = {
     .bdrv_read          = raw_read,
     .bdrv_write         = raw_write,
     .bdrv_getlength     = raw_getlength,
+    .bdrv_get_allocated_file_size
+                        = raw_get_allocated_file_size,
 
     /* removable device support */
     .bdrv_is_inserted   = cdrom_is_inserted,
@@ -1503,6 +1522,8 @@ static BlockDriver bdrv_host_cdrom = {
     .bdrv_read          = raw_read,
     .bdrv_write         = raw_write,
     .bdrv_getlength     = raw_getlength,
+    .bdrv_get_allocated_file_size
+                        = raw_get_allocated_file_size,
 
     /* removable device support */
     .bdrv_is_inserted   = cdrom_is_inserted,
diff --git a/block/raw-win32.c b/block/raw-win32.c
index 56bd719..91067e7 100644
--- a/block/raw-win32.c
+++ b/block/raw-win32.c
@@ -213,6 +213,31 @@ static int64_t raw_getlength(BlockDriverState *bs)
     return l.QuadPart;
 }
 
+static int64_t raw_get_allocated_file_size(BlockDriverState *bs)
+{
+    typedef DWORD (WINAPI * get_compressed_t)(const char *filename,
+                                              DWORD * high);
+    get_compressed_t get_compressed;
+    struct _stati64 st;
+    const char *filename = bs->filename;
+    /* WinNT support GetCompressedFileSize to determine allocate size */
+    get_compressed =
+        (get_compressed_t) GetProcAddress(GetModuleHandle("kernel32"),
+                                            "GetCompressedFileSizeA");
+    if (get_compressed) {
+        DWORD high, low;
+        low = get_compressed(filename, &high);
+        if (low != 0xFFFFFFFFlu || GetLastError() == NO_ERROR) {
+            return (((int64_t) high) << 32) + low;
+        }
+    }
+
+    if (_stati64(filename, &st) < 0) {
+        return -1;
+    }
+    return st.st_size;
+}
+
 static int raw_create(const char *filename, QEMUOptionParameter *options)
 {
     int fd;
@@ -257,6 +282,8 @@ static BlockDriver bdrv_file = {
     .bdrv_write		= raw_write,
     .bdrv_truncate	= raw_truncate,
     .bdrv_getlength	= raw_getlength,
+    .bdrv_get_allocated_file_size
+                        = raw_get_allocated_file_size,
 
     .create_options = raw_create_options,
 };
@@ -419,6 +446,8 @@ static BlockDriver bdrv_host_device = {
     .bdrv_read		= raw_read,
     .bdrv_write	        = raw_write,
     .bdrv_getlength	= raw_getlength,
+    .bdrv_get_allocated_file_size
+                        = raw_get_allocated_file_size,
 };
 
 static void bdrv_file_init(void)
diff --git a/block/vmdk.c b/block/vmdk.c
index de08d0c..37478d2 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -1289,6 +1289,29 @@ static int vmdk_flush(BlockDriverState *bs)
     return ret;
 }
 
+static int64_t vmdk_get_allocated_file_size(BlockDriverState *bs)
+{
+    int i;
+    int64_t ret = 0;
+    int64_t r;
+    BDRVVmdkState *s = bs->opaque;
+
+    ret = bdrv_get_allocated_file_size(bs->file);
+    if (ret < 0) {
+        return ret;
+    }
+    for (i = 0; i < s->num_extents; i++) {
+        if (s->extents[i].file == bs->file) {
+            continue;
+        }
+        r = bdrv_get_allocated_file_size(s->extents[i].file);
+        if (r < 0) {
+            return r;
+        }
+        ret += r;
+    }
+    return ret;
+}
 
 static QEMUOptionParameter vmdk_create_options[] = {
     {
@@ -1327,6 +1350,7 @@ static BlockDriver bdrv_vmdk = {
     .bdrv_create    = vmdk_create,
     .bdrv_flush     = vmdk_flush,
     .bdrv_is_allocated  = vmdk_is_allocated,
+    .bdrv_get_allocated_file_size  = vmdk_get_allocated_file_size,
 
     .create_options = vmdk_create_options,
 };
diff --git a/block_int.h b/block_int.h
index 8a7b6cb..efb6803 100644
--- a/block_int.h
+++ b/block_int.h
@@ -86,6 +86,7 @@ struct BlockDriver {
     const char *protocol_name;
     int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
     int64_t (*bdrv_getlength)(BlockDriverState *bs);
+    int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs);
     int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,
                                  const uint8_t *buf, int nb_sectors);
 
diff --git a/qemu-img.c b/qemu-img.c
index 54137a4..b205e98 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -1024,35 +1024,6 @@ out:
     return 0;
 }
 
-#ifdef _WIN32
-static int64_t get_allocated_file_size(const char *filename)
-{
-    typedef DWORD (WINAPI * get_compressed_t)(const char *filename, DWORD *high);
-    get_compressed_t get_compressed;
-    struct _stati64 st;
-
-    /* WinNT support GetCompressedFileSize to determine allocate size */
-    get_compressed = (get_compressed_t) GetProcAddress(GetModuleHandle("kernel32"), "GetCompressedFileSizeA");
-    if (get_compressed) {
-    	DWORD high, low;
-    	low = get_compressed(filename, &high);
-    	if (low != 0xFFFFFFFFlu || GetLastError() == NO_ERROR)
-	    return (((int64_t) high) << 32) + low;
-    }
-
-    if (_stati64(filename, &st) < 0)
-        return -1;
-    return st.st_size;
-}
-#else
-static int64_t get_allocated_file_size(const char *filename)
-{
-    struct stat st;
-    if (stat(filename, &st) < 0)
-        return -1;
-    return (int64_t)st.st_blocks * 512;
-}
-#endif
 
 static void dump_snapshots(BlockDriverState *bs)
 {
@@ -1112,7 +1083,7 @@ static int img_info(int argc, char **argv)
     bdrv_get_format(bs, fmt_name, sizeof(fmt_name));
     bdrv_get_geometry(bs, &total_sectors);
     get_human_readable_size(size_buf, sizeof(size_buf), total_sectors * 512);
-    allocated_size = get_allocated_file_size(filename);
+    allocated_size = bdrv_get_allocated_file_size(bs);
     if (allocated_size < 0) {
         snprintf(dsize_buf, sizeof(dsize_buf), "unavailable");
     } else {
-- 
1.7.6