[mirror_qemu.git] / block / qed.h

/*
 * QEMU Enhanced Disk Format
 *
 * Copyright IBM, Corp. 2010
 *
 * Authors:
 *  Stefan Hajnoczi   <stefanha@linux.vnet.ibm.com>
 *  Anthony Liguori   <aliguori@us.ibm.com>
 *
 * This work is licensed under the terms of the GNU LGPL, version 2 or later.
 * See the COPYING.LIB file in the top-level directory.
 *
 */

#ifndef BLOCK_QED_H
#define BLOCK_QED_H

#include "block/block_int.h"

/* The layout of a QED file is as follows:
 *
 * +--------+----------+----------+----------+-----+
 * | header | L1 table | cluster0 | cluster1 | ... |
 * +--------+----------+----------+----------+-----+
 *
 * There is a 2-level pagetable for cluster allocation:
 *
 *                     +----------+
 *                     | L1 table |
 *                     +----------+
 *                ,------'  |  '------.
 *           +----------+   |    +----------+
 *           | L2 table |  ...   | L2 table |
 *           +----------+        +----------+
 *       ,------'  |  '------.
 *  +----------+   |    +----------+
 *  |   Data   |  ...   |   Data   |
 *  +----------+        +----------+
 *
 * The L1 table is fixed size and always present.  L2 tables are allocated on
 * demand.  The L1 table size determines the maximum possible image size; it
 * can be influenced using the cluster_size and table_size values.
 *
 * All fields are little-endian on disk.
 */
#define  QED_DEFAULT_CLUSTER_SIZE  65536
enum {
    QED_MAGIC = 'Q' | 'E' << 8 | 'D' << 16 | '\0' << 24,

    /* The image supports a backing file */
    QED_F_BACKING_FILE = 0x01,

    /* The image needs a consistency check before use */
    QED_F_NEED_CHECK = 0x02,

    /* The backing file format must not be probed, treat as raw image */
    QED_F_BACKING_FORMAT_NO_PROBE = 0x04,

    /* Feature bits must be used when the on-disk format changes */
    QED_FEATURE_MASK = QED_F_BACKING_FILE | /* supported feature bits */
                       QED_F_NEED_CHECK |
                       QED_F_BACKING_FORMAT_NO_PROBE,
    QED_COMPAT_FEATURE_MASK = 0,            /* supported compat feature bits */
    QED_AUTOCLEAR_FEATURE_MASK = 0,         /* supported autoclear feature bits */

    /* Data is stored in groups of sectors called clusters.  Cluster size must
     * be large to avoid keeping too much metadata.  I/O requests that have
     * sub-cluster size will require read-modify-write.
     */
    QED_MIN_CLUSTER_SIZE = 4 * 1024, /* in bytes */
    QED_MAX_CLUSTER_SIZE = 64 * 1024 * 1024,

    /* Allocated clusters are tracked using a 2-level pagetable.  Table size is
     * a multiple of clusters so large maximum image sizes can be supported
     * without jacking up the cluster size too much.
     */
    QED_MIN_TABLE_SIZE = 1,        /* in clusters */
    QED_MAX_TABLE_SIZE = 16,
    QED_DEFAULT_TABLE_SIZE = 4,

    /* Delay to flush and clean image after last allocating write completes */
    QED_NEED_CHECK_TIMEOUT = 5,    /* in seconds */
};

typedef struct {
    uint32_t magic;                 /* QED\0 */

    uint32_t cluster_size;          /* in bytes */
    uint32_t table_size;            /* for L1 and L2 tables, in clusters */
    uint32_t header_size;           /* in clusters */

    uint64_t features;              /* format feature bits */
    uint64_t compat_features;       /* compatible feature bits */
    uint64_t autoclear_features;    /* self-resetting feature bits */

    uint64_t l1_table_offset;       /* in bytes */
    uint64_t image_size;            /* total logical image size, in bytes */

    /* if (features & QED_F_BACKING_FILE) */
    uint32_t backing_filename_offset; /* in bytes from start of header */
    uint32_t backing_filename_size;   /* in bytes */
} QEMU_PACKED QEDHeader;

typedef struct {
    uint64_t offsets[0];            /* in bytes */
} QEDTable;

/* The L2 cache is a simple write-through cache for L2 structures */
typedef struct CachedL2Table {
    QEDTable *table;
    uint64_t offset;    /* offset=0 indicates an invalidate entry */
    QTAILQ_ENTRY(CachedL2Table) node;
    int ref;
} CachedL2Table;

typedef struct {
    QTAILQ_HEAD(, CachedL2Table) entries;
    unsigned int n_entries;
} L2TableCache;

typedef struct QEDRequest {
    CachedL2Table *l2_table;
} QEDRequest;

enum {
    QED_AIOCB_WRITE = 0x0001,       /* read or write? */
    QED_AIOCB_ZERO  = 0x0002,       /* zero write, used with QED_AIOCB_WRITE */
};

typedef struct QEDAIOCB {
    BlockAIOCB common;
    QEMUBH *bh;
    int bh_ret;                     /* final return status for completion bh */
    QSIMPLEQ_ENTRY(QEDAIOCB) next;  /* next request */
    int flags;                      /* QED_AIOCB_* bits ORed together */
    uint64_t end_pos;               /* request end on block device, in bytes */

    /* User scatter-gather list */
    QEMUIOVector *qiov;
    size_t qiov_offset;             /* byte count already processed */

    /* Current cluster scatter-gather list */
    QEMUIOVector cur_qiov;
    QEMUIOVector *backing_qiov;
    uint64_t cur_pos;               /* position on block device, in bytes */
    uint64_t cur_cluster;           /* cluster offset in image file */
    unsigned int cur_nclusters;     /* number of clusters being accessed */
    int find_cluster_ret;           /* used for L1/L2 update */

    QEDRequest request;
} QEDAIOCB;

typedef struct {
    BlockDriverState *bs;           /* device */
    uint64_t file_size;             /* length of image file, in bytes */

    QEDHeader header;               /* always cpu-endian */
    QEDTable *l1_table;
    L2TableCache l2_cache;          /* l2 table cache */
    uint32_t table_nelems;
    uint32_t l1_shift;
    uint32_t l2_shift;
    uint32_t l2_mask;

    /* Allocating write request queue */
    QSIMPLEQ_HEAD(, QEDAIOCB) allocating_write_reqs;
    bool allocating_write_reqs_plugged;

    /* Periodic flush and clear need check flag */
    QEMUTimer *need_check_timer;
} BDRVQEDState;

enum {
    QED_CLUSTER_FOUND,         /* cluster found */
    QED_CLUSTER_ZERO,          /* zero cluster found */
    QED_CLUSTER_L2,            /* cluster missing in L2 */
    QED_CLUSTER_L1,            /* cluster missing in L1 */
};

/**
 * qed_find_cluster() completion callback
 *
 * @opaque:     User data for completion callback
 * @ret:        QED_CLUSTER_FOUND   Success
 *              QED_CLUSTER_L2      Data cluster unallocated in L2
 *              QED_CLUSTER_L1      L2 unallocated in L1
 *              -errno              POSIX error occurred
 * @offset:     Data cluster offset
 * @len:        Contiguous bytes starting from cluster offset
 *
 * This function is invoked when qed_find_cluster() completes.
 *
 * On success ret is QED_CLUSTER_FOUND and offset/len are a contiguous range
 * in the image file.
 *
 * On failure ret is QED_CLUSTER_L2 or QED_CLUSTER_L1 for missing L2 or L1
 * table offset, respectively.  len is number of contiguous unallocated bytes.
 */
typedef void QEDFindClusterFunc(void *opaque, int ret, uint64_t offset, size_t len);

/**
 * Generic callback for chaining async callbacks
 */
typedef struct {
    BlockCompletionFunc *cb;
    void *opaque;
} GenericCB;

void *gencb_alloc(size_t len, BlockCompletionFunc *cb, void *opaque);
void gencb_complete(void *opaque, int ret);

/**
 * Header functions
 */
int qed_write_header_sync(BDRVQEDState *s);

/**
 * L2 cache functions
 */
void qed_init_l2_cache(L2TableCache *l2_cache);
void qed_free_l2_cache(L2TableCache *l2_cache);
CachedL2Table *qed_alloc_l2_cache_entry(L2TableCache *l2_cache);
void qed_unref_l2_cache_entry(CachedL2Table *entry);
CachedL2Table *qed_find_l2_cache_entry(L2TableCache *l2_cache, uint64_t offset);
void qed_commit_l2_cache_entry(L2TableCache *l2_cache, CachedL2Table *l2_table);

/**
 * Table I/O functions
 */
int qed_read_l1_table_sync(BDRVQEDState *s);
void qed_write_l1_table(BDRVQEDState *s, unsigned int index, unsigned int n,
                        BlockCompletionFunc *cb, void *opaque);
int qed_write_l1_table_sync(BDRVQEDState *s, unsigned int index,
                            unsigned int n);
int qed_read_l2_table_sync(BDRVQEDState *s, QEDRequest *request,
                           uint64_t offset);
void qed_read_l2_table(BDRVQEDState *s, QEDRequest *request, uint64_t offset,
                       BlockCompletionFunc *cb, void *opaque);
void qed_write_l2_table(BDRVQEDState *s, QEDRequest *request,
                        unsigned int index, unsigned int n, bool flush,
                        BlockCompletionFunc *cb, void *opaque);
int qed_write_l2_table_sync(BDRVQEDState *s, QEDRequest *request,
                            unsigned int index, unsigned int n, bool flush);

/**
 * Cluster functions
 */
void qed_find_cluster(BDRVQEDState *s, QEDRequest *request, uint64_t pos,
                      size_t len, QEDFindClusterFunc *cb, void *opaque);

/**
 * Consistency check
 */
int qed_check(BDRVQEDState *s, BdrvCheckResult *result, bool fix);

QEDTable *qed_alloc_table(BDRVQEDState *s);

/**
 * Round down to the start of a cluster
 */
static inline uint64_t qed_start_of_cluster(BDRVQEDState *s, uint64_t offset)
{
    return offset & ~(uint64_t)(s->header.cluster_size - 1);
}

static inline uint64_t qed_offset_into_cluster(BDRVQEDState *s, uint64_t offset)
{
    return offset & (s->header.cluster_size - 1);
}

static inline uint64_t qed_bytes_to_clusters(BDRVQEDState *s, uint64_t bytes)
{
    return qed_start_of_cluster(s, bytes + (s->header.cluster_size - 1)) /
           (s->header.cluster_size - 1);
}

static inline unsigned int qed_l1_index(BDRVQEDState *s, uint64_t pos)
{
    return pos >> s->l1_shift;
}

static inline unsigned int qed_l2_index(BDRVQEDState *s, uint64_t pos)
{
    return (pos >> s->l2_shift) & s->l2_mask;
}

/**
 * Test if a cluster offset is valid
 */
static inline bool qed_check_cluster_offset(BDRVQEDState *s, uint64_t offset)
{
    uint64_t header_size = (uint64_t)s->header.header_size *
                           s->header.cluster_size;

    if (offset & (s->header.cluster_size - 1)) {
        return false;
    }
    return offset >= header_size && offset < s->file_size;
}

/**
 * Test if a table offset is valid
 */
static inline bool qed_check_table_offset(BDRVQEDState *s, uint64_t offset)
{
    uint64_t end_offset = offset + (s->header.table_size - 1) *
                          s->header.cluster_size;

    /* Overflow check */
    if (end_offset <= offset) {
        return false;
    }

    return qed_check_cluster_offset(s, offset) &&
           qed_check_cluster_offset(s, end_offset);
}

static inline bool qed_offset_is_cluster_aligned(BDRVQEDState *s,
                                                 uint64_t offset)
{
    if (qed_offset_into_cluster(s, offset)) {
        return false;
    }
    return true;
}

static inline bool qed_offset_is_unalloc_cluster(uint64_t offset)
{
    if (offset == 0) {
        return true;
    }
    return false;
}

static inline bool qed_offset_is_zero_cluster(uint64_t offset)
{
    if (offset == 1) {
        return true;
    }
    return false;
}

#endif /* BLOCK_QED_H */
Commit	Line	Data
75411d23 SH	1	/*
	2	* QEMU Enhanced Disk Format
	3	*
	4	* Copyright IBM, Corp. 2010
	5	*
	6	* Authors:
	7	* Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
	8	* Anthony Liguori <aliguori@us.ibm.com>
	9	*
	10	* This work is licensed under the terms of the GNU LGPL, version 2 or later.
	11	* See the COPYING.LIB file in the top-level directory.
	12	*
	13	*/
	14
	15	#ifndef BLOCK_QED_H
	16	#define BLOCK_QED_H
	17
737e150e	18	#include "block/block_int.h"
75411d23 SH	19
	20	/* The layout of a QED file is as follows:
	21	*
	22	* +--------+----------+----------+----------+-----+
	23	* \| header \| L1 table \| cluster0 \| cluster1 \| ... \|
	24	* +--------+----------+----------+----------+-----+
	25	*
	26	* There is a 2-level pagetable for cluster allocation:
	27	*
	28	* +----------+
	29	* \| L1 table \|
	30	* +----------+
	31	* ,------' \| '------.
	32	* +----------+ \| +----------+
	33	* \| L2 table \| ... \| L2 table \|
	34	* +----------+ +----------+
	35	* ,------' \| '------.
	36	* +----------+ \| +----------+
	37	* \| Data \| ... \| Data \|
	38	* +----------+ +----------+
	39	*
	40	* The L1 table is fixed size and always present. L2 tables are allocated on
	41	* demand. The L1 table size determines the maximum possible image size; it
	42	* can be influenced using the cluster_size and table_size values.
	43	*
	44	* All fields are little-endian on disk.
	45	*/
7ab74849	46	#define QED_DEFAULT_CLUSTER_SIZE 65536
75411d23 SH	47	enum {
	48	QED_MAGIC = 'Q' \| 'E' << 8 \| 'D' << 16 \| '\0' << 24,
	49
	50	/* The image supports a backing file */
	51	QED_F_BACKING_FILE = 0x01,
	52
01979a98 SH	53	/* The image needs a consistency check before use */
	54	QED_F_NEED_CHECK = 0x02,
	55
75411d23 SH	56	/* The backing file format must not be probed, treat as raw image */
	57	QED_F_BACKING_FORMAT_NO_PROBE = 0x04,
	58
	59	/* Feature bits must be used when the on-disk format changes */
	60	QED_FEATURE_MASK = QED_F_BACKING_FILE \| /* supported feature bits */
01979a98	61	QED_F_NEED_CHECK \|
75411d23 SH	62	QED_F_BACKING_FORMAT_NO_PROBE,
	63	QED_COMPAT_FEATURE_MASK = 0, /* supported compat feature bits */
	64	QED_AUTOCLEAR_FEATURE_MASK = 0, /* supported autoclear feature bits */
	65
	66	/* Data is stored in groups of sectors called clusters. Cluster size must
	67	* be large to avoid keeping too much metadata. I/O requests that have
	68	* sub-cluster size will require read-modify-write.
	69	*/
	70	QED_MIN_CLUSTER_SIZE = 4 * 1024, /* in bytes */
	71	QED_MAX_CLUSTER_SIZE = 64 * 1024 * 1024,
75411d23 SH	72
	73	/* Allocated clusters are tracked using a 2-level pagetable. Table size is
	74	* a multiple of clusters so large maximum image sizes can be supported
	75	* without jacking up the cluster size too much.
	76	*/
	77	QED_MIN_TABLE_SIZE = 1, /* in clusters */
	78	QED_MAX_TABLE_SIZE = 16,
	79	QED_DEFAULT_TABLE_SIZE = 4,
6f321e93 SH	80
	81	/* Delay to flush and clean image after last allocating write completes */
	82	QED_NEED_CHECK_TIMEOUT = 5, /* in seconds */
75411d23 SH	83	};
	84
	85	typedef struct {
	86	uint32_t magic; /* QED\0 */
	87
	88	uint32_t cluster_size; /* in bytes */
	89	uint32_t table_size; /* for L1 and L2 tables, in clusters */
	90	uint32_t header_size; /* in clusters */
	91
	92	uint64_t features; /* format feature bits */
	93	uint64_t compat_features; /* compatible feature bits */
	94	uint64_t autoclear_features; /* self-resetting feature bits */
	95
	96	uint64_t l1_table_offset; /* in bytes */
	97	uint64_t image_size; /* total logical image size, in bytes */
	98
	99	/* if (features & QED_F_BACKING_FILE) */
	100	uint32_t backing_filename_offset; /* in bytes from start of header */
	101	uint32_t backing_filename_size; /* in bytes */
687fb893	102	} QEMU_PACKED QEDHeader;
75411d23	103
298800ca SH	104	typedef struct {
	105	uint64_t offsets[0]; /* in bytes */
	106	} QEDTable;
	107
	108	/* The L2 cache is a simple write-through cache for L2 structures */
	109	typedef struct CachedL2Table {
	110	QEDTable *table;
	111	uint64_t offset; /* offset=0 indicates an invalidate entry */
	112	QTAILQ_ENTRY(CachedL2Table) node;
	113	int ref;
	114	} CachedL2Table;
	115
	116	typedef struct {
	117	QTAILQ_HEAD(, CachedL2Table) entries;
	118	unsigned int n_entries;
	119	} L2TableCache;
	120
	121	typedef struct QEDRequest {
	122	CachedL2Table *l2_table;
	123	} QEDRequest;
	124
6e4f59bd SH	125	enum {
6e4f59bd SH	126	QED_AIOCB_WRITE = 0x0001, /* read or write? */
0e71be19	127	QED_AIOCB_ZERO = 0x0002, /* zero write, used with QED_AIOCB_WRITE */
6e4f59bd SH	128	};
6e4f59bd SH	129
eabba580	130	typedef struct QEDAIOCB {
7c84b1b8	131	BlockAIOCB common;
eabba580 SH	132	QEMUBH *bh;
	133	int bh_ret; /* final return status for completion bh */
	134	QSIMPLEQ_ENTRY(QEDAIOCB) next; /* next request */
6e4f59bd	135	int flags; /* QED_AIOCB_* bits ORed together */
eabba580 SH	136	uint64_t end_pos; /* request end on block device, in bytes */
	137
	138	/* User scatter-gather list */
	139	QEMUIOVector *qiov;
	140	size_t qiov_offset; /* byte count already processed */
	141
	142	/* Current cluster scatter-gather list */
	143	QEMUIOVector cur_qiov;
f06ee3d4	144	QEMUIOVector *backing_qiov;
eabba580 SH	145	uint64_t cur_pos; /* position on block device, in bytes */
	146	uint64_t cur_cluster; /* cluster offset in image file */
	147	unsigned int cur_nclusters; /* number of clusters being accessed */
	148	int find_cluster_ret; /* used for L1/L2 update */
	149
	150	QEDRequest request;
	151	} QEDAIOCB;
	152
75411d23 SH	153	typedef struct {
	154	BlockDriverState bs; / device */
	155	uint64_t file_size; /* length of image file, in bytes */
	156
	157	QEDHeader header; /* always cpu-endian */
298800ca SH	158	QEDTable *l1_table;
298800ca SH	159	L2TableCache l2_cache; /* l2 table cache */
75411d23 SH	160	uint32_t table_nelems;
	161	uint32_t l1_shift;
	162	uint32_t l2_shift;
	163	uint32_t l2_mask;
eabba580 SH	164
	165	/* Allocating write request queue */
	166	QSIMPLEQ_HEAD(, QEDAIOCB) allocating_write_reqs;
6f321e93 SH	167	bool allocating_write_reqs_plugged;
	168
	169	/* Periodic flush and clear need check flag */
	170	QEMUTimer *need_check_timer;
75411d23 SH	171	} BDRVQEDState;
75411d23 SH	172
298800ca SH	173	enum {
298800ca SH	174	QED_CLUSTER_FOUND, /* cluster found */
21df65b6	175	QED_CLUSTER_ZERO, /* zero cluster found */
298800ca SH	176	QED_CLUSTER_L2, /* cluster missing in L2 */
	177	QED_CLUSTER_L1, /* cluster missing in L1 */
	178	};
	179
	180	/**
	181	* qed_find_cluster() completion callback
	182	*
	183	* @opaque: User data for completion callback
	184	* @ret: QED_CLUSTER_FOUND Success
	185	* QED_CLUSTER_L2 Data cluster unallocated in L2
	186	* QED_CLUSTER_L1 L2 unallocated in L1
	187	* -errno POSIX error occurred
	188	* @offset: Data cluster offset
	189	* @len: Contiguous bytes starting from cluster offset
	190	*
	191	* This function is invoked when qed_find_cluster() completes.
	192	*
	193	* On success ret is QED_CLUSTER_FOUND and offset/len are a contiguous range
	194	* in the image file.
	195	*
	196	* On failure ret is QED_CLUSTER_L2 or QED_CLUSTER_L1 for missing L2 or L1
	197	* table offset, respectively. len is number of contiguous unallocated bytes.
	198	*/
	199	typedef void QEDFindClusterFunc(void *opaque, int ret, uint64_t offset, size_t len);
	200
	201	/**
	202	* Generic callback for chaining async callbacks
	203	*/
	204	typedef struct {
097310b5	205	BlockCompletionFunc *cb;
298800ca SH	206	void *opaque;
	207	} GenericCB;
	208
097310b5	209	void gencb_alloc(size_t len, BlockCompletionFunc cb, void *opaque);
298800ca SH	210	void gencb_complete(void *opaque, int ret);
298800ca SH	211
b10170ac SH	212	/**
	213	* Header functions
	214	*/
	215	int qed_write_header_sync(BDRVQEDState *s);
	216
298800ca SH	217	/**
	218	* L2 cache functions
	219	*/
	220	void qed_init_l2_cache(L2TableCache *l2_cache);
	221	void qed_free_l2_cache(L2TableCache *l2_cache);
	222	CachedL2Table qed_alloc_l2_cache_entry(L2TableCache l2_cache);
	223	void qed_unref_l2_cache_entry(CachedL2Table *entry);
	224	CachedL2Table qed_find_l2_cache_entry(L2TableCache l2_cache, uint64_t offset);
	225	void qed_commit_l2_cache_entry(L2TableCache l2_cache, CachedL2Table l2_table);
	226
	227	/**
	228	* Table I/O functions
	229	*/
	230	int qed_read_l1_table_sync(BDRVQEDState *s);
	231	void qed_write_l1_table(BDRVQEDState *s, unsigned int index, unsigned int n,
097310b5	232	BlockCompletionFunc cb, void opaque);
298800ca SH	233	int qed_write_l1_table_sync(BDRVQEDState *s, unsigned int index,
	234	unsigned int n);
	235	int qed_read_l2_table_sync(BDRVQEDState s, QEDRequest request,
	236	uint64_t offset);
	237	void qed_read_l2_table(BDRVQEDState s, QEDRequest request, uint64_t offset,
097310b5	238	BlockCompletionFunc cb, void opaque);
298800ca SH	239	void qed_write_l2_table(BDRVQEDState s, QEDRequest request,
298800ca SH	240	unsigned int index, unsigned int n, bool flush,
097310b5	241	BlockCompletionFunc cb, void opaque);
298800ca SH	242	int qed_write_l2_table_sync(BDRVQEDState s, QEDRequest request,
	243	unsigned int index, unsigned int n, bool flush);
	244
	245	/**
	246	* Cluster functions
	247	*/
	248	void qed_find_cluster(BDRVQEDState s, QEDRequest request, uint64_t pos,
	249	size_t len, QEDFindClusterFunc cb, void opaque);
	250
	251	/**
	252	* Consistency check
	253	*/
	254	int qed_check(BDRVQEDState s, BdrvCheckResult result, bool fix);
	255
	256	QEDTable qed_alloc_table(BDRVQEDState s);
	257
75411d23 SH	258	/**
	259	* Round down to the start of a cluster
	260	*/
	261	static inline uint64_t qed_start_of_cluster(BDRVQEDState *s, uint64_t offset)
	262	{
	263	return offset & ~(uint64_t)(s->header.cluster_size - 1);
	264	}
	265
298800ca SH	266	static inline uint64_t qed_offset_into_cluster(BDRVQEDState *s, uint64_t offset)
	267	{
	268	return offset & (s->header.cluster_size - 1);
	269	}
	270
19dfc44a	271	static inline uint64_t qed_bytes_to_clusters(BDRVQEDState *s, uint64_t bytes)
298800ca SH	272	{
	273	return qed_start_of_cluster(s, bytes + (s->header.cluster_size - 1)) /
	274	(s->header.cluster_size - 1);
	275	}
	276
	277	static inline unsigned int qed_l1_index(BDRVQEDState *s, uint64_t pos)
	278	{
	279	return pos >> s->l1_shift;
	280	}
	281
	282	static inline unsigned int qed_l2_index(BDRVQEDState *s, uint64_t pos)
	283	{
	284	return (pos >> s->l2_shift) & s->l2_mask;
	285	}
	286
75411d23 SH	287	/**
	288	* Test if a cluster offset is valid
	289	*/
	290	static inline bool qed_check_cluster_offset(BDRVQEDState *s, uint64_t offset)
	291	{
	292	uint64_t header_size = (uint64_t)s->header.header_size *
	293	s->header.cluster_size;
	294
	295	if (offset & (s->header.cluster_size - 1)) {
	296	return false;
	297	}
	298	return offset >= header_size && offset < s->file_size;
	299	}
	300
	301	/**
	302	* Test if a table offset is valid
	303	*/
	304	static inline bool qed_check_table_offset(BDRVQEDState *s, uint64_t offset)
	305	{
	306	uint64_t end_offset = offset + (s->header.table_size - 1) *
	307	s->header.cluster_size;
	308
	309	/* Overflow check */
	310	if (end_offset <= offset) {
	311	return false;
	312	}
	313
	314	return qed_check_cluster_offset(s, offset) &&
	315	qed_check_cluster_offset(s, end_offset);
	316	}
	317
21df65b6 AL	318	static inline bool qed_offset_is_cluster_aligned(BDRVQEDState *s,
	319	uint64_t offset)
	320	{
	321	if (qed_offset_into_cluster(s, offset)) {
	322	return false;
	323	}
	324	return true;
	325	}
	326
	327	static inline bool qed_offset_is_unalloc_cluster(uint64_t offset)
	328	{
	329	if (offset == 0) {
	330	return true;
	331	}
	332	return false;
	333	}
	334
	335	static inline bool qed_offset_is_zero_cluster(uint64_t offset)
	336	{
	337	if (offset == 1) {
	338	return true;
	339	}
	340	return false;
	341	}
	342
75411d23	343	#endif /* BLOCK_QED_H */