diff options
| -rw-r--r-- | block-vmdk.c | 91 |
1 files changed, 74 insertions, 17 deletions
diff --git a/block-vmdk.c b/block-vmdk.c index 1cc4988534..f80bf07b75 100644 --- a/block-vmdk.c +++ b/block-vmdk.c @@ -2,6 +2,7 @@ * Block driver for the VMDK format * * Copyright (c) 2004 Fabrice Bellard + * Copyright (c) 2005 Filip Navara * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal @@ -24,9 +25,6 @@ #include "vl.h" #include "block_int.h" -/* XXX: this code is untested */ -/* XXX: add write support */ - #define VMDK3_MAGIC (('C' << 24) | ('O' << 16) | ('W' << 8) | 'D') #define VMDK4_MAGIC (('K' << 24) | ('D' << 16) | ('M' << 8) | 'V') @@ -56,14 +54,16 @@ typedef struct { int64_t grain_offset; char filler[1]; char check_bytes[4]; -} VMDK4Header; +} __attribute__((packed)) VMDK4Header; #define L2_CACHE_SIZE 16 typedef struct BDRVVmdkState { int fd; int64_t l1_table_offset; + int64_t l1_backup_table_offset; uint32_t *l1_table; + uint32_t *l1_backup_table; unsigned int l1_size; uint32_t l1_entry_sectors; @@ -96,9 +96,13 @@ static int vmdk_open(BlockDriverState *bs, const char *filename) uint32_t magic; int l1_size; - fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE); - if (fd < 0) - return -1; + fd = open(filename, O_RDWR | O_BINARY | O_LARGEFILE); + if (fd < 0) { + fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE); + if (fd < 0) + return -1; + bs->read_only = 1; + } if (read(fd, &magic, sizeof(magic)) != sizeof(magic)) goto fail; magic = be32_to_cpu(magic); @@ -111,7 +115,8 @@ static int vmdk_open(BlockDriverState *bs, const char *filename) s->l2_size = 1 << 9; s->l1_size = 1 << 6; bs->total_sectors = le32_to_cpu(header.disk_sectors); - s->l1_table_offset = le32_to_cpu(header.l1dir_offset) * 512; + s->l1_table_offset = le32_to_cpu(header.l1dir_offset) << 9; + s->l1_backup_table_offset = 0; s->l1_entry_sectors = s->l2_size * s->cluster_sectors; } else if (magic == VMDK4_MAGIC) { VMDK4Header header; @@ -126,7 +131,8 @@ static int vmdk_open(BlockDriverState *bs, const char *filename) goto fail; s->l1_size = (bs->total_sectors + s->l1_entry_sectors - 1) / s->l1_entry_sectors; - s->l1_table_offset = le64_to_cpu(header.rgd_offset) * 512; + s->l1_table_offset = le64_to_cpu(header.rgd_offset) << 9; + s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9; } else { goto fail; } @@ -143,14 +149,26 @@ static int vmdk_open(BlockDriverState *bs, const char *filename) le32_to_cpus(&s->l1_table[i]); } + if (s->l1_backup_table_offset) { + s->l1_backup_table = qemu_malloc(l1_size); + if (!s->l1_backup_table) + goto fail; + if (lseek(fd, s->l1_backup_table_offset, SEEK_SET) == -1) + goto fail; + if (read(fd, s->l1_backup_table, l1_size) != l1_size) + goto fail; + for(i = 0; i < s->l1_size; i++) { + le32_to_cpus(&s->l1_backup_table[i]); + } + } + s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint32_t)); if (!s->l2_cache) goto fail; s->fd = fd; - /* XXX: currently only read only */ - bs->read_only = 1; return 0; fail: + qemu_free(s->l1_backup_table); qemu_free(s->l1_table); qemu_free(s->l2_cache); close(fd); @@ -158,12 +176,12 @@ static int vmdk_open(BlockDriverState *bs, const char *filename) } static uint64_t get_cluster_offset(BlockDriverState *bs, - uint64_t offset) + uint64_t offset, int allocate) { BDRVVmdkState *s = bs->opaque; unsigned int l1_index, l2_offset, l2_index; int min_index, i, j; - uint32_t min_count, *l2_table; + uint32_t min_count, *l2_table, tmp; uint64_t cluster_offset; l1_index = (offset >> 9) / s->l1_entry_sectors; @@ -172,7 +190,6 @@ static uint64_t get_cluster_offset(BlockDriverState *bs, l2_offset = s->l1_table[l1_index]; if (!l2_offset) return 0; - for(i = 0; i < L2_CACHE_SIZE; i++) { if (l2_offset == s->l2_cache_offsets[i]) { /* increment the hit count */ @@ -204,6 +221,26 @@ static uint64_t get_cluster_offset(BlockDriverState *bs, found: l2_index = ((offset >> 9) / s->cluster_sectors) % s->l2_size; cluster_offset = le32_to_cpu(l2_table[l2_index]); + if (!cluster_offset) { + if (!allocate) + return 0; + cluster_offset = lseek(s->fd, 0, SEEK_END); + ftruncate(s->fd, cluster_offset + (s->cluster_sectors << 9)); + cluster_offset >>= 9; + /* update L2 table */ + tmp = cpu_to_le32(cluster_offset); + l2_table[l2_index] = tmp; + lseek(s->fd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)), SEEK_SET); + if (write(s->fd, &tmp, sizeof(tmp)) != sizeof(tmp)) + return 0; + /* update backup L2 table */ + if (s->l1_backup_table_offset != 0) { + l2_offset = s->l1_backup_table[l1_index]; + lseek(s->fd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)), SEEK_SET); + if (write(s->fd, &tmp, sizeof(tmp)) != sizeof(tmp)) + return 0; + } + } cluster_offset <<= 9; return cluster_offset; } @@ -215,7 +252,7 @@ static int vmdk_is_allocated(BlockDriverState *bs, int64_t sector_num, int index_in_cluster, n; uint64_t cluster_offset; - cluster_offset = get_cluster_offset(bs, sector_num << 9); + cluster_offset = get_cluster_offset(bs, sector_num << 9, 0); index_in_cluster = sector_num % s->cluster_sectors; n = s->cluster_sectors - index_in_cluster; if (n > nb_sectors) @@ -232,7 +269,7 @@ static int vmdk_read(BlockDriverState *bs, int64_t sector_num, uint64_t cluster_offset; while (nb_sectors > 0) { - cluster_offset = get_cluster_offset(bs, sector_num << 9); + cluster_offset = get_cluster_offset(bs, sector_num << 9, 0); index_in_cluster = sector_num % s->cluster_sectors; n = s->cluster_sectors - index_in_cluster; if (n > nb_sectors) @@ -255,7 +292,27 @@ static int vmdk_read(BlockDriverState *bs, int64_t sector_num, static int vmdk_write(BlockDriverState *bs, int64_t sector_num, const uint8_t *buf, int nb_sectors) { - return -1; + BDRVVmdkState *s = bs->opaque; + int ret, index_in_cluster, n; + uint64_t cluster_offset; + + while (nb_sectors > 0) { + index_in_cluster = sector_num & (s->cluster_sectors - 1); + n = s->cluster_sectors - index_in_cluster; + if (n > nb_sectors) + n = nb_sectors; + cluster_offset = get_cluster_offset(bs, sector_num << 9, 1); + if (!cluster_offset) + return -1; + lseek(s->fd, cluster_offset + index_in_cluster * 512, SEEK_SET); + ret = write(s->fd, buf, n * 512); + if (ret != n * 512) + return -1; + nb_sectors -= n; + sector_num += n; + buf += n * 512; + } + return 0; } static void vmdk_close(BlockDriverState *bs) |