[mirror_qemu.git] / block-vmdk.c

/*
 * 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
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include "vl.h"
#include "block_int.h"

#define VMDK3_MAGIC (('C' << 24) | ('O' << 16) | ('W' << 8) | 'D')
#define VMDK4_MAGIC (('K' << 24) | ('D' << 16) | ('M' << 8) | 'V')

typedef struct {
    uint32_t version;
    uint32_t flags;
    uint32_t disk_sectors;
    uint32_t granularity;
    uint32_t l1dir_offset;
    uint32_t l1dir_size;
    uint32_t file_sectors;
    uint32_t cylinders;
    uint32_t heads;
    uint32_t sectors_per_track;
} VMDK3Header;

typedef struct {
    uint32_t version;
    uint32_t flags;
    int64_t capacity;
    int64_t granularity;
    int64_t desc_offset;
    int64_t desc_size;
    int32_t num_gtes_per_gte;
    int64_t rgd_offset;
    int64_t gd_offset;
    int64_t grain_offset;
    char filler[1];
    char check_bytes[4];
} __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;

    unsigned int l2_size;
    uint32_t *l2_cache;
    uint32_t l2_cache_offsets[L2_CACHE_SIZE];
    uint32_t l2_cache_counts[L2_CACHE_SIZE];

    unsigned int cluster_sectors;
} BDRVVmdkState;

static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename)
{
    uint32_t magic;

    if (buf_size < 4)
        return 0;
    magic = be32_to_cpu(*(uint32_t *)buf);
    if (magic == VMDK3_MAGIC ||
        magic == VMDK4_MAGIC)
        return 100;
    else
        return 0;
}

static int vmdk_open(BlockDriverState *bs, const char *filename)
{
    BDRVVmdkState *s = bs->opaque;
    int fd, i;
    uint32_t magic;
    int l1_size;

    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);
    if (magic == VMDK3_MAGIC) {
        VMDK3Header header;
        if (read(fd, &header, sizeof(header)) != 
            sizeof(header))
            goto fail;
        s->cluster_sectors = le32_to_cpu(header.granularity);
        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) << 9;
        s->l1_backup_table_offset = 0;
        s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
    } else if (magic == VMDK4_MAGIC) {
        VMDK4Header header;
        
        if (read(fd, &header, sizeof(header)) != sizeof(header))
            goto fail;
        bs->total_sectors = le32_to_cpu(header.capacity);
        s->cluster_sectors = le32_to_cpu(header.granularity);
        s->l2_size = le32_to_cpu(header.num_gtes_per_gte);
        s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
        if (s->l1_entry_sectors <= 0)
            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) << 9;
        s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9;
    } else {
        goto fail;
    }
    /* read the L1 table */
    l1_size = s->l1_size * sizeof(uint32_t);
    s->l1_table = qemu_malloc(l1_size);
    if (!s->l1_table)
        goto fail;
    if (lseek(fd, s->l1_table_offset, SEEK_SET) == -1)
        goto fail;
    if (read(fd, s->l1_table, l1_size) != l1_size)
        goto fail;
    for(i = 0; i < s->l1_size; i++) {
        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;
    return 0;
 fail:
    qemu_free(s->l1_backup_table);
    qemu_free(s->l1_table);
    qemu_free(s->l2_cache);
    close(fd);
    return -1;
}

static uint64_t get_cluster_offset(BlockDriverState *bs,
                                   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;
    uint64_t cluster_offset;
    
    l1_index = (offset >> 9) / s->l1_entry_sectors;
    if (l1_index >= s->l1_size)
        return 0;
    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 */
            if (++s->l2_cache_counts[i] == 0xffffffff) {
                for(j = 0; j < L2_CACHE_SIZE; j++) {
                    s->l2_cache_counts[j] >>= 1;
                }
            }
            l2_table = s->l2_cache + (i * s->l2_size);
            goto found;
        }
    }
    /* not found: load a new entry in the least used one */
    min_index = 0;
    min_count = 0xffffffff;
    for(i = 0; i < L2_CACHE_SIZE; i++) {
        if (s->l2_cache_counts[i] < min_count) {
            min_count = s->l2_cache_counts[i];
            min_index = i;
        }
    }
    l2_table = s->l2_cache + (min_index * s->l2_size);
    lseek(s->fd, (int64_t)l2_offset * 512, SEEK_SET);
    if (read(s->fd, l2_table, s->l2_size * sizeof(uint32_t)) != 
        s->l2_size * sizeof(uint32_t))
        return 0;
    s->l2_cache_offsets[min_index] = l2_offset;
    s->l2_cache_counts[min_index] = 1;
 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;
}

static int vmdk_is_allocated(BlockDriverState *bs, int64_t sector_num, 
                             int nb_sectors, int *pnum)
{
    BDRVVmdkState *s = bs->opaque;
    int index_in_cluster, n;
    uint64_t cluster_offset;

    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)
        n = nb_sectors;
    *pnum = n;
    return (cluster_offset != 0);
}

static int vmdk_read(BlockDriverState *bs, int64_t sector_num, 
                    uint8_t *buf, int nb_sectors)
{
    BDRVVmdkState *s = bs->opaque;
    int ret, index_in_cluster, n;
    uint64_t cluster_offset;
    
    while (nb_sectors > 0) {
        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)
            n = nb_sectors;
        if (!cluster_offset) {
            memset(buf, 0, 512 * n);
        } else {
            lseek(s->fd, cluster_offset + index_in_cluster * 512, SEEK_SET);
            ret = read(s->fd, buf, n * 512);
            if (ret != n * 512) 
                return -1;
        }
        nb_sectors -= n;
        sector_num += n;
        buf += n * 512;
    }
    return 0;
}

static int vmdk_write(BlockDriverState *bs, int64_t sector_num, 
                     const uint8_t *buf, int nb_sectors)
{
    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)
{
    BDRVVmdkState *s = bs->opaque;
    qemu_free(s->l1_table);
    qemu_free(s->l2_cache);
    close(s->fd);
}

BlockDriver bdrv_vmdk = {
    "vmdk",
    sizeof(BDRVVmdkState),
    vmdk_probe,
    vmdk_open,
    vmdk_read,
    vmdk_write,
    vmdk_close,
    NULL, /* no create yet */
    vmdk_is_allocated,
};
Commit	Line	Data
ea2384d3 FB	1	/*
	2	* Block driver for the VMDK format
	3	*
	4	* Copyright (c) 2004 Fabrice Bellard
ff1afc72	5	* Copyright (c) 2005 Filip Navara
ea2384d3 FB	6	*
	7	* Permission is hereby granted, free of charge, to any person obtaining a copy
	8	* of this software and associated documentation files (the "Software"), to deal
	9	* in the Software without restriction, including without limitation the rights
	10	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	11	* copies of the Software, and to permit persons to whom the Software is
	12	* furnished to do so, subject to the following conditions:
	13	*
	14	* The above copyright notice and this permission notice shall be included in
	15	* all copies or substantial portions of the Software.
	16	*
	17	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	18	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	19	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	20	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	21	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	22	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	23	* THE SOFTWARE.
	24	*/
	25	#include "vl.h"
	26	#include "block_int.h"
	27
ea2384d3 FB	28	#define VMDK3_MAGIC (('C' << 24) \| ('O' << 16) \| ('W' << 8) \| 'D')
	29	#define VMDK4_MAGIC (('K' << 24) \| ('D' << 16) \| ('M' << 8) \| 'V')
	30
	31	typedef struct {
	32	uint32_t version;
	33	uint32_t flags;
	34	uint32_t disk_sectors;
	35	uint32_t granularity;
	36	uint32_t l1dir_offset;
	37	uint32_t l1dir_size;
	38	uint32_t file_sectors;
	39	uint32_t cylinders;
	40	uint32_t heads;
	41	uint32_t sectors_per_track;
	42	} VMDK3Header;
	43
	44	typedef struct {
	45	uint32_t version;
	46	uint32_t flags;
	47	int64_t capacity;
	48	int64_t granularity;
	49	int64_t desc_offset;
	50	int64_t desc_size;
	51	int32_t num_gtes_per_gte;
	52	int64_t rgd_offset;
	53	int64_t gd_offset;
	54	int64_t grain_offset;
	55	char filler[1];
	56	char check_bytes[4];
ff1afc72	57	} __attribute__((packed)) VMDK4Header;
ea2384d3 FB	58
	59	#define L2_CACHE_SIZE 16
	60
	61	typedef struct BDRVVmdkState {
	62	int fd;
	63	int64_t l1_table_offset;
ff1afc72	64	int64_t l1_backup_table_offset;
ea2384d3	65	uint32_t *l1_table;
ff1afc72	66	uint32_t *l1_backup_table;
ea2384d3 FB	67	unsigned int l1_size;
	68	uint32_t l1_entry_sectors;
	69
	70	unsigned int l2_size;
	71	uint32_t *l2_cache;
	72	uint32_t l2_cache_offsets[L2_CACHE_SIZE];
	73	uint32_t l2_cache_counts[L2_CACHE_SIZE];
	74
	75	unsigned int cluster_sectors;
	76	} BDRVVmdkState;
	77
	78	static int vmdk_probe(const uint8_t buf, int buf_size, const char filename)
	79	{
	80	uint32_t magic;
	81
	82	if (buf_size < 4)
	83	return 0;
	84	magic = be32_to_cpu((uint32_t )buf);
	85	if (magic == VMDK3_MAGIC \|\|
	86	magic == VMDK4_MAGIC)
	87	return 100;
	88	else
	89	return 0;
	90	}
	91
	92	static int vmdk_open(BlockDriverState bs, const char filename)
	93	{
	94	BDRVVmdkState *s = bs->opaque;
	95	int fd, i;
	96	uint32_t magic;
	97	int l1_size;
	98
ff1afc72 FB	99	fd = open(filename, O_RDWR \| O_BINARY \| O_LARGEFILE);
	100	if (fd < 0) {
	101	fd = open(filename, O_RDONLY \| O_BINARY \| O_LARGEFILE);
	102	if (fd < 0)
	103	return -1;
	104	bs->read_only = 1;
	105	}
ea2384d3 FB	106	if (read(fd, &magic, sizeof(magic)) != sizeof(magic))
ea2384d3 FB	107	goto fail;
7143c62c	108	magic = be32_to_cpu(magic);
ea2384d3 FB	109	if (magic == VMDK3_MAGIC) {
	110	VMDK3Header header;
	111	if (read(fd, &header, sizeof(header)) !=
	112	sizeof(header))
	113	goto fail;
	114	s->cluster_sectors = le32_to_cpu(header.granularity);
	115	s->l2_size = 1 << 9;
	116	s->l1_size = 1 << 6;
	117	bs->total_sectors = le32_to_cpu(header.disk_sectors);
ff1afc72 FB	118	s->l1_table_offset = le32_to_cpu(header.l1dir_offset) << 9;
ff1afc72 FB	119	s->l1_backup_table_offset = 0;
ea2384d3 FB	120	s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
	121	} else if (magic == VMDK4_MAGIC) {
	122	VMDK4Header header;
	123
	124	if (read(fd, &header, sizeof(header)) != sizeof(header))
	125	goto fail;
	126	bs->total_sectors = le32_to_cpu(header.capacity);
	127	s->cluster_sectors = le32_to_cpu(header.granularity);
	128	s->l2_size = le32_to_cpu(header.num_gtes_per_gte);
	129	s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
	130	if (s->l1_entry_sectors <= 0)
	131	goto fail;
	132	s->l1_size = (bs->total_sectors + s->l1_entry_sectors - 1)
	133	/ s->l1_entry_sectors;
ff1afc72 FB	134	s->l1_table_offset = le64_to_cpu(header.rgd_offset) << 9;
ff1afc72 FB	135	s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9;
ea2384d3 FB	136	} else {
	137	goto fail;
	138	}
	139	/* read the L1 table */
	140	l1_size = s->l1_size * sizeof(uint32_t);
	141	s->l1_table = qemu_malloc(l1_size);
	142	if (!s->l1_table)
	143	goto fail;
7143c62c FB	144	if (lseek(fd, s->l1_table_offset, SEEK_SET) == -1)
	145	goto fail;
	146	if (read(fd, s->l1_table, l1_size) != l1_size)
ea2384d3 FB	147	goto fail;
	148	for(i = 0; i < s->l1_size; i++) {
	149	le32_to_cpus(&s->l1_table[i]);
	150	}
	151
ff1afc72 FB	152	if (s->l1_backup_table_offset) {
	153	s->l1_backup_table = qemu_malloc(l1_size);
	154	if (!s->l1_backup_table)
	155	goto fail;
	156	if (lseek(fd, s->l1_backup_table_offset, SEEK_SET) == -1)
	157	goto fail;
	158	if (read(fd, s->l1_backup_table, l1_size) != l1_size)
	159	goto fail;
	160	for(i = 0; i < s->l1_size; i++) {
	161	le32_to_cpus(&s->l1_backup_table[i]);
	162	}
	163	}
	164
ea2384d3 FB	165	s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint32_t));
	166	if (!s->l2_cache)
	167	goto fail;
	168	s->fd = fd;
ea2384d3 FB	169	return 0;
ea2384d3 FB	170	fail:
ff1afc72	171	qemu_free(s->l1_backup_table);
ea2384d3 FB	172	qemu_free(s->l1_table);
	173	qemu_free(s->l2_cache);
	174	close(fd);
	175	return -1;
	176	}
	177
	178	static uint64_t get_cluster_offset(BlockDriverState *bs,
ff1afc72	179	uint64_t offset, int allocate)
ea2384d3 FB	180	{
	181	BDRVVmdkState *s = bs->opaque;
	182	unsigned int l1_index, l2_offset, l2_index;
	183	int min_index, i, j;
ff1afc72	184	uint32_t min_count, *l2_table, tmp;
ea2384d3 FB	185	uint64_t cluster_offset;
	186
	187	l1_index = (offset >> 9) / s->l1_entry_sectors;
	188	if (l1_index >= s->l1_size)
	189	return 0;
	190	l2_offset = s->l1_table[l1_index];
	191	if (!l2_offset)
	192	return 0;
ea2384d3 FB	193	for(i = 0; i < L2_CACHE_SIZE; i++) {
	194	if (l2_offset == s->l2_cache_offsets[i]) {
	195	/* increment the hit count */
	196	if (++s->l2_cache_counts[i] == 0xffffffff) {
	197	for(j = 0; j < L2_CACHE_SIZE; j++) {
	198	s->l2_cache_counts[j] >>= 1;
	199	}
	200	}
	201	l2_table = s->l2_cache + (i * s->l2_size);
	202	goto found;
	203	}
	204	}
	205	/* not found: load a new entry in the least used one */
	206	min_index = 0;
	207	min_count = 0xffffffff;
	208	for(i = 0; i < L2_CACHE_SIZE; i++) {
	209	if (s->l2_cache_counts[i] < min_count) {
	210	min_count = s->l2_cache_counts[i];
	211	min_index = i;
	212	}
	213	}
	214	l2_table = s->l2_cache + (min_index * s->l2_size);
	215	lseek(s->fd, (int64_t)l2_offset * 512, SEEK_SET);
	216	if (read(s->fd, l2_table, s->l2_size * sizeof(uint32_t)) !=
	217	s->l2_size * sizeof(uint32_t))
	218	return 0;
	219	s->l2_cache_offsets[min_index] = l2_offset;
	220	s->l2_cache_counts[min_index] = 1;
	221	found:
	222	l2_index = ((offset >> 9) / s->cluster_sectors) % s->l2_size;
	223	cluster_offset = le32_to_cpu(l2_table[l2_index]);
ff1afc72 FB	224	if (!cluster_offset) {
	225	if (!allocate)
	226	return 0;
	227	cluster_offset = lseek(s->fd, 0, SEEK_END);
	228	ftruncate(s->fd, cluster_offset + (s->cluster_sectors << 9));
	229	cluster_offset >>= 9;
	230	/* update L2 table */
	231	tmp = cpu_to_le32(cluster_offset);
	232	l2_table[l2_index] = tmp;
	233	lseek(s->fd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)), SEEK_SET);
	234	if (write(s->fd, &tmp, sizeof(tmp)) != sizeof(tmp))
	235	return 0;
	236	/* update backup L2 table */
	237	if (s->l1_backup_table_offset != 0) {
	238	l2_offset = s->l1_backup_table[l1_index];
	239	lseek(s->fd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)), SEEK_SET);
	240	if (write(s->fd, &tmp, sizeof(tmp)) != sizeof(tmp))
	241	return 0;
	242	}
	243	}
ea2384d3 FB	244	cluster_offset <<= 9;
	245	return cluster_offset;
	246	}
	247
	248	static int vmdk_is_allocated(BlockDriverState *bs, int64_t sector_num,
	249	int nb_sectors, int *pnum)
	250	{
	251	BDRVVmdkState *s = bs->opaque;
	252	int index_in_cluster, n;
	253	uint64_t cluster_offset;
	254
ff1afc72	255	cluster_offset = get_cluster_offset(bs, sector_num << 9, 0);
ea2384d3 FB	256	index_in_cluster = sector_num % s->cluster_sectors;
	257	n = s->cluster_sectors - index_in_cluster;
	258	if (n > nb_sectors)
	259	n = nb_sectors;
	260	*pnum = n;
	261	return (cluster_offset != 0);
	262	}
	263
	264	static int vmdk_read(BlockDriverState *bs, int64_t sector_num,
	265	uint8_t *buf, int nb_sectors)
	266	{
	267	BDRVVmdkState *s = bs->opaque;
	268	int ret, index_in_cluster, n;
	269	uint64_t cluster_offset;
	270
	271	while (nb_sectors > 0) {
ff1afc72	272	cluster_offset = get_cluster_offset(bs, sector_num << 9, 0);
ea2384d3 FB	273	index_in_cluster = sector_num % s->cluster_sectors;
	274	n = s->cluster_sectors - index_in_cluster;
	275	if (n > nb_sectors)
	276	n = nb_sectors;
	277	if (!cluster_offset) {
	278	memset(buf, 0, 512 * n);
	279	} else {
d5249393	280	lseek(s->fd, cluster_offset + index_in_cluster * 512, SEEK_SET);
ea2384d3 FB	281	ret = read(s->fd, buf, n * 512);
	282	if (ret != n * 512)
	283	return -1;
	284	}
	285	nb_sectors -= n;
	286	sector_num += n;
	287	buf += n * 512;
	288	}
	289	return 0;
	290	}
	291
	292	static int vmdk_write(BlockDriverState *bs, int64_t sector_num,
	293	const uint8_t *buf, int nb_sectors)
	294	{
ff1afc72 FB	295	BDRVVmdkState *s = bs->opaque;
	296	int ret, index_in_cluster, n;
	297	uint64_t cluster_offset;
	298
	299	while (nb_sectors > 0) {
	300	index_in_cluster = sector_num & (s->cluster_sectors - 1);
	301	n = s->cluster_sectors - index_in_cluster;
	302	if (n > nb_sectors)
	303	n = nb_sectors;
	304	cluster_offset = get_cluster_offset(bs, sector_num << 9, 1);
	305	if (!cluster_offset)
	306	return -1;
	307	lseek(s->fd, cluster_offset + index_in_cluster * 512, SEEK_SET);
	308	ret = write(s->fd, buf, n * 512);
	309	if (ret != n * 512)
	310	return -1;
	311	nb_sectors -= n;
	312	sector_num += n;
	313	buf += n * 512;
	314	}
	315	return 0;
ea2384d3 FB	316	}
ea2384d3 FB	317
e2731add	318	static void vmdk_close(BlockDriverState *bs)
ea2384d3 FB	319	{
	320	BDRVVmdkState *s = bs->opaque;
	321	qemu_free(s->l1_table);
	322	qemu_free(s->l2_cache);
	323	close(s->fd);
	324	}
	325
	326	BlockDriver bdrv_vmdk = {
	327	"vmdk",
	328	sizeof(BDRVVmdkState),
	329	vmdk_probe,
	330	vmdk_open,
	331	vmdk_read,
	332	vmdk_write,
	333	vmdk_close,
	334	NULL, /* no create yet */
	335	vmdk_is_allocated,
	336	};