diff options
| -rw-r--r-- | block-vmdk.c | 149 |
1 files changed, 117 insertions, 32 deletions
diff --git a/block-vmdk.c b/block-vmdk.c index 28df8ae466..e595eabe50 100644 --- a/block-vmdk.c +++ b/block-vmdk.c @@ -75,8 +75,25 @@ typedef struct BDRVVmdkState { unsigned int cluster_sectors; uint32_t parent_cid; + int is_parent; } BDRVVmdkState; +typedef struct VmdkMetaData { + uint32_t offset; + unsigned int l1_index; + unsigned int l2_index; + unsigned int l2_offset; + int valid; +} VmdkMetaData; + +typedef struct ActiveBDRVState{ + BlockDriverState *hd; // active image handler + uint64_t cluster_offset; // current write offset +}ActiveBDRVState; + +static ActiveBDRVState activeBDRV; + + static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename) { uint32_t magic; @@ -305,7 +322,7 @@ static void vmdk_parent_close(BlockDriverState *bs) bdrv_close(bs->backing_hd); } - +int parent_open = 0; static int vmdk_parent_open(BlockDriverState *bs, const char * filename) { BDRVVmdkState *s = bs->opaque; @@ -339,8 +356,10 @@ static int vmdk_parent_open(BlockDriverState *bs, const char * filename) bdrv_close(s->hd); return -1; } - if (bdrv_open(s->hd->backing_hd, parent_img_name, 0) < 0) + parent_open = 1; + if (bdrv_open(s->hd->backing_hd, parent_img_name, BDRV_O_RDONLY) < 0) goto failure; + parent_open = 0; } return 0; @@ -352,6 +371,11 @@ static int vmdk_open(BlockDriverState *bs, const char *filename, int flags) uint32_t magic; int l1_size, i, ret; + if (parent_open) + // Parent must be opened as RO. + flags = BDRV_O_RDONLY; + fprintf(stderr, "(VMDK) image open: flags=0x%x filename=%s\n", flags, bs->filename); + ret = bdrv_file_open(&s->hd, filename, flags); if (ret < 0) return ret; @@ -387,6 +411,11 @@ static int vmdk_open(BlockDriverState *bs, const char *filename, int flags) s->l1_table_offset = le64_to_cpu(header.rgd_offset) << 9; s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9; + if (parent_open) + s->is_parent = 1; + else + s->is_parent = 0; + // try to open parent images, if exist if (vmdk_parent_open(bs, filename) != 0) goto fail; @@ -430,7 +459,8 @@ static int vmdk_open(BlockDriverState *bs, const char *filename, int flags) return -1; } -static uint64_t get_cluster_offset(BlockDriverState *bs, uint64_t offset, int allocate); +static uint64_t get_cluster_offset(BlockDriverState *bs, VmdkMetaData *m_data, + uint64_t offset, int allocate); static int get_whole_cluster(BlockDriverState *bs, uint64_t cluster_offset, uint64_t offset, int allocate) @@ -446,27 +476,55 @@ static int get_whole_cluster(BlockDriverState *bs, uint64_t cluster_offset, if (!vmdk_is_cid_valid(bs)) return -1; - parent_cluster_offset = get_cluster_offset(s->hd->backing_hd, offset, allocate); - if (bdrv_pread(ps->hd, parent_cluster_offset, whole_grain, ps->cluster_sectors*512) != - ps->cluster_sectors*512) - return -1; - if (bdrv_pwrite(s->hd, cluster_offset << 9, whole_grain, sizeof(whole_grain)) != - sizeof(whole_grain)) + parent_cluster_offset = get_cluster_offset(s->hd->backing_hd, NULL, offset, allocate); + + if (parent_cluster_offset) { + BDRVVmdkState *act_s = activeBDRV.hd->opaque; + + if (bdrv_pread(ps->hd, parent_cluster_offset, whole_grain, ps->cluster_sectors*512) != ps->cluster_sectors*512) + return -1; + + //Write grain only into the active image + if (bdrv_pwrite(act_s->hd, activeBDRV.cluster_offset << 9, whole_grain, sizeof(whole_grain)) != sizeof(whole_grain)) + return -1; + } + } + return 0; +} + +static int vmdk_L2update(BlockDriverState *bs, VmdkMetaData *m_data) +{ + BDRVVmdkState *s = bs->opaque; + + /* update L2 table */ + if (bdrv_pwrite(s->hd, ((int64_t)m_data->l2_offset * 512) + (m_data->l2_index * sizeof(m_data->offset)), + &(m_data->offset), sizeof(m_data->offset)) != sizeof(m_data->offset)) + return -1; + /* update backup L2 table */ + if (s->l1_backup_table_offset != 0) { + m_data->l2_offset = s->l1_backup_table[m_data->l1_index]; + if (bdrv_pwrite(s->hd, ((int64_t)m_data->l2_offset * 512) + (m_data->l2_index * sizeof(m_data->offset)), + &(m_data->offset), sizeof(m_data->offset)) != sizeof(m_data->offset)) return -1; } + return 0; } -static uint64_t get_cluster_offset(BlockDriverState *bs, +static uint64_t get_cluster_offset(BlockDriverState *bs, VmdkMetaData *m_data, 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, tmp; + uint32_t min_count, *l2_table, tmp = 0; uint64_t cluster_offset; - + int status; + + if (m_data) + m_data->valid = 0; + l1_index = (offset >> 9) / s->l1_entry_sectors; if (l1_index >= s->l1_size) return 0; @@ -504,32 +562,45 @@ 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) { struct stat file_buf; if (!allocate) return 0; - stat(s->hd->filename, &file_buf); - cluster_offset = file_buf.st_size; - bdrv_truncate(s->hd, cluster_offset + (s->cluster_sectors << 9)); - - cluster_offset >>= 9; - /* update L2 table */ - tmp = cpu_to_le32(cluster_offset); - l2_table[l2_index] = tmp; - if (bdrv_pwrite(s->hd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)), - &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]; - if (bdrv_pwrite(s->hd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)), - &tmp, sizeof(tmp)) != sizeof(tmp)) + // Avoid the L2 tables update for the images that have snapshots. + if (!s->is_parent) { + status = stat(s->hd->filename, &file_buf); + if (status == -1) { + fprintf(stderr, "(VMDK) Fail file stat: filename =%s size=0x%lx errno=%s\n", + s->hd->filename, (uint64_t)file_buf.st_size, strerror(errno)); return 0; + } + cluster_offset = file_buf.st_size; + bdrv_truncate(s->hd, cluster_offset + (s->cluster_sectors << 9)); + + cluster_offset >>= 9; + tmp = cpu_to_le32(cluster_offset); + l2_table[l2_index] = tmp; + // Save the active image state + activeBDRV.cluster_offset = cluster_offset; + activeBDRV.hd = bs; } - + /* First of all we write grain itself, to avoid race condition + * that may to corrupt the image. + * This problem may occur because of insufficient space on host disk + * or inappropriate VM shutdown. + */ if (get_whole_cluster(bs, cluster_offset, offset, allocate) == -1) return 0; + + if (m_data) { + m_data->offset = tmp; + m_data->l1_index = l1_index; + m_data->l2_index = l2_index; + m_data->l2_offset = l2_offset; + m_data->valid = 1; + } } cluster_offset <<= 9; return cluster_offset; @@ -542,7 +613,7 @@ 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, 0); + cluster_offset = get_cluster_offset(bs, NULL, sector_num << 9, 0); index_in_cluster = sector_num % s->cluster_sectors; n = s->cluster_sectors - index_in_cluster; if (n > nb_sectors) @@ -559,7 +630,7 @@ 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, 0); + cluster_offset = get_cluster_offset(bs, NULL, sector_num << 9, 0); index_in_cluster = sector_num % s->cluster_sectors; n = s->cluster_sectors - index_in_cluster; if (n > nb_sectors) @@ -590,20 +661,34 @@ static int vmdk_write(BlockDriverState *bs, int64_t sector_num, const uint8_t *buf, int nb_sectors) { BDRVVmdkState *s = bs->opaque; + VmdkMetaData m_data; int index_in_cluster, n; uint64_t cluster_offset; static int cid_update = 0; + if (sector_num > bs->total_sectors) { + fprintf(stderr, + "(VMDK) Wrong offset: sector_num=0x%lx total_sectors=0x%lx\n", + sector_num, bs->total_sectors); + return -1; + } + 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); + cluster_offset = get_cluster_offset(bs, &m_data, sector_num << 9, 1); if (!cluster_offset) return -1; + if (bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512) return -1; + if (m_data.valid) { + /* update L2 tables */ + if (vmdk_L2update(bs, &m_data) == -1) + return -1; + } nb_sectors -= n; sector_num += n; buf += n * 512; |