block/vpc: update comments to be compliant w/coding guidelines

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Jeff Cody 2016-03-22 23:33:44 -04:00 committed by Kevin Wolf
parent 32f6439cf7
commit 9c057d0b68

View File

@ -45,7 +45,7 @@ enum vhd_type {
VHD_DIFFERENCING = 4,
};
// Seconds since Jan 1, 2000 0:00:00 (UTC)
/* Seconds since Jan 1, 2000 0:00:00 (UTC) */
#define VHD_TIMESTAMP_BASE 946684800
#define VHD_CHS_MAX_C 65535LL
@ -57,22 +57,22 @@ enum vhd_type {
#define VPC_OPT_FORCE_SIZE "force_size"
// always big-endian
/* always big-endian */
typedef struct vhd_footer {
char creator[8]; // "conectix"
char creator[8]; /* "conectix" */
uint32_t features;
uint32_t version;
// Offset of next header structure, 0xFFFFFFFF if none
/* Offset of next header structure, 0xFFFFFFFF if none */
uint64_t data_offset;
// Seconds since Jan 1, 2000 0:00:00 (UTC)
/* Seconds since Jan 1, 2000 0:00:00 (UTC) */
uint32_t timestamp;
char creator_app[4]; // "vpc "
char creator_app[4]; /* e.g., "vpc " */
uint16_t major;
uint16_t minor;
char creator_os[4]; // "Wi2k"
char creator_os[4]; /* "Wi2k" */
uint64_t orig_size;
uint64_t current_size;
@ -83,29 +83,29 @@ typedef struct vhd_footer {
uint32_t type;
// Checksum of the Hard Disk Footer ("one's complement of the sum of all
// the bytes in the footer without the checksum field")
/* Checksum of the Hard Disk Footer ("one's complement of the sum of all
the bytes in the footer without the checksum field") */
uint32_t checksum;
// UUID used to identify a parent hard disk (backing file)
/* UUID used to identify a parent hard disk (backing file) */
uint8_t uuid[16];
uint8_t in_saved_state;
} QEMU_PACKED VHDFooter;
typedef struct vhd_dyndisk_header {
char magic[8]; // "cxsparse"
char magic[8]; /* "cxsparse" */
// Offset of next header structure, 0xFFFFFFFF if none
/* Offset of next header structure, 0xFFFFFFFF if none */
uint64_t data_offset;
// Offset of the Block Allocation Table (BAT)
/* Offset of the Block Allocation Table (BAT) */
uint64_t table_offset;
uint32_t version;
uint32_t max_table_entries; // 32bit/entry
uint32_t max_table_entries; /* 32bit/entry */
// 2 MB by default, must be a power of two
/* 2 MB by default, must be a power of two */
uint32_t block_size;
uint32_t checksum;
@ -113,7 +113,7 @@ typedef struct vhd_dyndisk_header {
uint32_t parent_timestamp;
uint32_t reserved;
// Backing file name (in UTF-16)
/* Backing file name (in UTF-16) */
uint8_t parent_name[512];
struct {
@ -278,9 +278,9 @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags,
/* Write 'checksum' back to footer, or else will leave it with zero. */
footer->checksum = cpu_to_be32(checksum);
// The visible size of a image in Virtual PC depends on the geometry
// rather than on the size stored in the footer (the size in the footer
// is too large usually)
/* The visible size of a image in Virtual PC depends on the geometry
rather than on the size stored in the footer (the size in the footer
is too large usually) */
bs->total_sectors = (int64_t)
be16_to_cpu(footer->cyls) * footer->heads * footer->secs_per_cyl;
@ -466,16 +466,16 @@ 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)
return -1; // not allocated
return -1; /* not allocated */
bitmap_offset = 512 * (uint64_t) s->pagetable[pagetable_index];
block_offset = bitmap_offset + s->bitmap_size + (512 * pageentry_index);
// We must ensure that we don't write to any sectors which are marked as
// unused in the bitmap. We get away with setting all bits in the block
// bitmap each time we write to a new block. This might cause Virtual PC to
// miss sparse read optimization, but it's not a problem in terms of
// correctness.
/* We must ensure that we don't write to any sectors which are marked as
unused in the bitmap. We get away with setting all bits in the block
bitmap each time we write to a new block. This might cause Virtual PC to
miss sparse read optimization, but it's not a problem in terms of
correctness. */
if (write && (s->last_bitmap_offset != bitmap_offset)) {
uint8_t bitmap[s->bitmap_size];
@ -521,18 +521,18 @@ static int64_t alloc_block(BlockDriverState* bs, int64_t sector_num)
int ret;
uint8_t bitmap[s->bitmap_size];
// Check if sector_num is valid
/* Check if sector_num is valid */
if ((sector_num < 0) || (sector_num > bs->total_sectors))
return -1;
// Write entry into in-memory BAT
/* Write entry into in-memory BAT */
index = (sector_num * 512) / s->block_size;
if (s->pagetable[index] != 0xFFFFFFFF)
return -1;
s->pagetable[index] = s->free_data_block_offset / 512;
// Initialize the block's bitmap
/* Initialize the block's bitmap */
memset(bitmap, 0xff, s->bitmap_size);
ret = bdrv_pwrite_sync(bs->file->bs, s->free_data_block_offset, bitmap,
s->bitmap_size);
@ -540,13 +540,13 @@ static int64_t alloc_block(BlockDriverState* bs, int64_t sector_num)
return ret;
}
// Write new footer (the old one will be overwritten)
/* Write new footer (the old one will be overwritten) */
s->free_data_block_offset += s->block_size + s->bitmap_size;
ret = rewrite_footer(bs);
if (ret < 0)
goto fail;
// Write BAT entry to disk
/* Write BAT entry to disk */
bat_offset = s->bat_offset + (4 * index);
bat_value = cpu_to_be32(s->pagetable[index]);
ret = bdrv_pwrite_sync(bs->file->bs, bat_offset, &bat_value, 4);
@ -779,7 +779,7 @@ static int create_dynamic_disk(BlockBackend *blk, uint8_t *buf,
int ret;
int64_t offset = 0;
// Write the footer (twice: at the beginning and at the end)
/* Write the footer (twice: at the beginning and at the end) */
block_size = 0x200000;
num_bat_entries = (total_sectors + block_size / 512) / (block_size / 512);
@ -794,7 +794,7 @@ static int create_dynamic_disk(BlockBackend *blk, uint8_t *buf,
goto fail;
}
// Write the initial BAT
/* Write the initial BAT */
offset = 3 * 512;
memset(buf, 0xFF, 512);
@ -806,7 +806,7 @@ static int create_dynamic_disk(BlockBackend *blk, uint8_t *buf,
offset += 512;
}
// Prepare the Dynamic Disk Header
/* Prepare the Dynamic Disk Header */
memset(buf, 0, 1024);
memcpy(dyndisk_header->magic, "cxsparse", 8);
@ -823,7 +823,7 @@ static int create_dynamic_disk(BlockBackend *blk, uint8_t *buf,
dyndisk_header->checksum = cpu_to_be32(vpc_checksum(buf, 1024));
// Write the header
/* Write the header */
offset = 512;
ret = blk_pwrite(blk, offset, buf, 1024);