BDRV_SECTOR_SIZE is replaced by VHD_SECTOR_SIZE when the sector size
is VHD specific.
Signed-off-by: Stefan Weil <s...@weilnetz.de>
---
block/vpc.c | 59 ++++++++++++++++++++++++++++++++++-------------------------
1 file changed, 34 insertions(+), 25 deletions(-)
diff --git a/block/vpc.c b/block/vpc.c
index e8968c2..8434a91 100644
--- a/block/vpc.c
+++ b/block/vpc.c
@@ -37,6 +37,20 @@
#define FOOTER_SIZE 512
+/* By default, VHD uses a block size of 2 MiB for dynamic disk images. */
+#define VHD_DEFAULT_BLOCK_SIZE 0x200000
+
+/* VHD uses linked data structures with 64 bit links.
+ * 0xffffffffffffffff terminates the chain.
+ * Note: The spec is actually wrong here for data_offset, it says
+ * 0xffffffff, but MS tools expect all 64 bits to be set. */
+#define VHD_NO_NEXT UINT64_MAX
+
+/* Last entry in page table. */
+#define VHD_NO_PAGE UINT32_MAX
+
+#define VHD_SECTOR_SIZE 512
+
//#define CACHE
enum vhd_type {
@@ -54,7 +68,7 @@ struct vhd_footer {
uint32_t features;
uint32_t version;
- // Offset of next header structure, 0xFFFFFFFF if none
+ /* Offset of next header structure or VHD_NO_NEXT */
uint64_t data_offset;
// Seconds since Jan 1, 2000 0:00:00 (UTC)
@@ -87,7 +101,7 @@ struct vhd_footer {
struct vhd_dyndisk_header {
char magic[8]; // "cxsparse"
- // Offset of next header structure, 0xFFFFFFFF if none
+ /* Offset of next header structure or VHD_NO_NEXT */
uint64_t data_offset;
// Offset of the Block Allocation Table (BAT)
@@ -201,7 +215,7 @@ static int vpc_open(BlockDriverState *bs, int flags)
/* The visible size of an image in Virtual PC may depend on the geometry
* rather than on the size stored in the footer (the size in the footer
* is usually larger). Nevertheless we must use the real size here. */
- bs->total_sectors = be64_to_cpu(footer->size) / 512;
+ bs->total_sectors = be64_to_cpu(footer->size) / VHD_SECTOR_SIZE;
/* Allow a maximum disk size of approximately 2 TB */
if (bs->total_sectors >= 65535LL * 255 * 255) {
@@ -241,7 +255,7 @@ static int vpc_open(BlockDriverState *bs, int flags)
for (i = 0; i < s->max_table_entries; i++) {
be32_to_cpus(&s->pagetable[i]);
- if (s->pagetable[i] != 0xFFFFFFFF) {
+ if (s->pagetable[i] != VHD_NO_PAGE) {
int64_t next = (512 * (int64_t) s->pagetable[i]) +
s->bitmap_size + s->block_size;
@@ -290,7 +304,7 @@ static inline int64_t get_sector_offset(BlockDriverState
*bs,
int64_t sector_num, int write)
{
BDRVVPCState *s = bs->opaque;
- uint64_t offset = sector_num * 512;
+ uint64_t offset = sector_num * VHD_SECTOR_SIZE;
uint64_t bitmap_offset, block_offset;
uint32_t pagetable_index, pageentry_index;
@@ -298,7 +312,7 @@ static inline int64_t get_sector_offset(BlockDriverState
*bs,
pageentry_index = (offset % s->block_size) / 512;
if (pagetable_index >= s->max_table_entries ||
- s->pagetable[pagetable_index] == 0xffffffff) {
+ s->pagetable[pagetable_index] == VHD_NO_PAGE) {
return -1; // not allocated
}
@@ -392,8 +406,8 @@ static int64_t alloc_block(BlockDriverState *bs, int64_t
sector_num)
}
// Write entry into in-memory BAT
- index = (sector_num * 512) / s->block_size;
- if (s->pagetable[index] != 0xFFFFFFFF) {
+ index = (sector_num * VHD_SECTOR_SIZE) / s->block_size;
+ if (s->pagetable[index] != VHD_NO_PAGE) {
return -1;
}
@@ -451,18 +465,17 @@ static int vpc_read(BlockDriverState *bs, int64_t
sector_num,
}
if (offset == -1) {
- memset(buf, 0, sectors * BDRV_SECTOR_SIZE);
+ memset(buf, 0, sectors * VHD_SECTOR_SIZE);
} else {
- ret = bdrv_pread(bs->file, offset, buf,
- sectors * BDRV_SECTOR_SIZE);
- if (ret != sectors * BDRV_SECTOR_SIZE) {
+ ret = bdrv_pread(bs->file, offset, buf, sectors * VHD_SECTOR_SIZE);
+ if (ret < 0) {
return -1;
}
}
nb_sectors -= sectors;
sector_num += sectors;
- buf += sectors * BDRV_SECTOR_SIZE;
+ buf += sectors * VHD_SECTOR_SIZE;
}
return 0;
}
@@ -506,14 +519,14 @@ static int vpc_write(BlockDriverState *bs, int64_t
sector_num,
}
}
- ret = bdrv_pwrite(bs->file, offset, buf, sectors * BDRV_SECTOR_SIZE);
- if (ret != sectors * BDRV_SECTOR_SIZE) {
+ ret = bdrv_pwrite(bs->file, offset, buf, sectors * VHD_SECTOR_SIZE);
+ if (ret < 0) {
return -1;
}
nb_sectors -= sectors;
sector_num += sectors;
- buf += sectors * BDRV_SECTOR_SIZE;
+ buf += sectors * VHD_SECTOR_SIZE;
}
return 0;
@@ -596,7 +609,7 @@ static int create_dynamic_disk(int fd, uint8_t *buf,
int64_t total_sectors)
int ret = -EIO;
// Write the footer (twice: at the beginning and at the end)
- block_size = 0x200000;
+ block_size = VHD_DEFAULT_BLOCK_SIZE;
num_bat_entries = (total_sectors + block_size / 512) / (block_size / 512);
if (write(fd, buf, FOOTER_SIZE) != FOOTER_SIZE) {
@@ -627,11 +640,7 @@ static int create_dynamic_disk(int fd, uint8_t *buf,
int64_t total_sectors)
memcpy(dyndisk_header->magic, "cxsparse", 8);
- /*
- * Note: The spec is actually wrong here for data_offset, it says
- * 0xFFFFFFFF, but MS tools expect all 64 bits to be set.
- */
- dyndisk_header->data_offset = be64_to_cpu(0xFFFFFFFFFFFFFFFFULL);
+ dyndisk_header->data_offset = be64_to_cpu(VHD_NO_NEXT);
dyndisk_header->table_offset = be64_to_cpu(3 * 512);
dyndisk_header->version = be32_to_cpu(0x00010000);
dyndisk_header->block_size = be32_to_cpu(block_size);
@@ -717,7 +726,7 @@ static int vpc_create(const char *filename,
QEMUOptionParameter *options)
* sectors requested until we get enough (or fail). This ensures that
* qemu-img convert doesn't truncate images, but rather rounds up.
*/
- total_sectors = total_size / BDRV_SECTOR_SIZE;
+ total_sectors = total_size / 512;
if (calculate_geometry(total_sectors, &cyls, &heads, &secs_per_cyl)) {
ret = -EFBIG;
goto fail;
@@ -736,7 +745,7 @@ static int vpc_create(const char *filename,
QEMUOptionParameter *options)
if (disk_type == VHD_DYNAMIC) {
footer->data_offset = be64_to_cpu(FOOTER_SIZE);
} else {
- footer->data_offset = be64_to_cpu(0xFFFFFFFFFFFFFFFFULL);
+ footer->data_offset = be64_to_cpu(VHD_NO_NEXT);
}
footer->timestamp = be32_to_cpu(time(NULL) - VHD_TIMESTAMP_BASE);
@@ -745,7 +754,7 @@ static int vpc_create(const char *filename,
QEMUOptionParameter *options)
footer->minor = be16_to_cpu(0x0003);
if (disk_type == VHD_DYNAMIC) {
footer->orig_size = be64_to_cpu(total_sectors * 512);
- footer->size = be64_to_cpu(total_sectors * 512);
+ footer->size = be64_to_cpu(total_sectors * VHD_SECTOR_SIZE);
} else {
footer->orig_size = be64_to_cpu(total_size);
footer->size = be64_to_cpu(total_size);
--
1.7.10.4
