[qemu.git] / hw / 9pfs / 9p.h

#ifndef QEMU_9P_H
#define QEMU_9P_H

#include <dirent.h>
#include <utime.h>
#include <sys/resource.h>
#include "fsdev/file-op-9p.h"
#include "fsdev/9p-iov-marshal.h"
#include "qemu/thread.h"
#include "qemu/coroutine.h"
#include "qemu/qht.h"

enum {
    P9_TLERROR = 6,
    P9_RLERROR,
    P9_TSTATFS = 8,
    P9_RSTATFS,
    P9_TLOPEN = 12,
    P9_RLOPEN,
    P9_TLCREATE = 14,
    P9_RLCREATE,
    P9_TSYMLINK = 16,
    P9_RSYMLINK,
    P9_TMKNOD = 18,
    P9_RMKNOD,
    P9_TRENAME = 20,
    P9_RRENAME,
    P9_TREADLINK = 22,
    P9_RREADLINK,
    P9_TGETATTR = 24,
    P9_RGETATTR,
    P9_TSETATTR = 26,
    P9_RSETATTR,
    P9_TXATTRWALK = 30,
    P9_RXATTRWALK,
    P9_TXATTRCREATE = 32,
    P9_RXATTRCREATE,
    P9_TREADDIR = 40,
    P9_RREADDIR,
    P9_TFSYNC = 50,
    P9_RFSYNC,
    P9_TLOCK = 52,
    P9_RLOCK,
    P9_TGETLOCK = 54,
    P9_RGETLOCK,
    P9_TLINK = 70,
    P9_RLINK,
    P9_TMKDIR = 72,
    P9_RMKDIR,
    P9_TRENAMEAT = 74,
    P9_RRENAMEAT,
    P9_TUNLINKAT = 76,
    P9_RUNLINKAT,
    P9_TVERSION = 100,
    P9_RVERSION,
    P9_TAUTH = 102,
    P9_RAUTH,
    P9_TATTACH = 104,
    P9_RATTACH,
    P9_TERROR = 106,
    P9_RERROR,
    P9_TFLUSH = 108,
    P9_RFLUSH,
    P9_TWALK = 110,
    P9_RWALK,
    P9_TOPEN = 112,
    P9_ROPEN,
    P9_TCREATE = 114,
    P9_RCREATE,
    P9_TREAD = 116,
    P9_RREAD,
    P9_TWRITE = 118,
    P9_RWRITE,
    P9_TCLUNK = 120,
    P9_RCLUNK,
    P9_TREMOVE = 122,
    P9_RREMOVE,
    P9_TSTAT = 124,
    P9_RSTAT,
    P9_TWSTAT = 126,
    P9_RWSTAT,
};


/* qid.types */
enum {
    P9_QTDIR = 0x80,
    P9_QTAPPEND = 0x40,
    P9_QTEXCL = 0x20,
    P9_QTMOUNT = 0x10,
    P9_QTAUTH = 0x08,
    P9_QTTMP = 0x04,
    P9_QTSYMLINK = 0x02,
    P9_QTLINK = 0x01,
    P9_QTFILE = 0x00,
};

typedef enum P9ProtoVersion {
    V9FS_PROTO_2000U = 0x01,
    V9FS_PROTO_2000L = 0x02,
} P9ProtoVersion;

/**
 * @brief Minimum message size supported by this 9pfs server.
 *
 * A client establishes a session by sending a Tversion request along with a
 * 'msize' parameter which suggests the server a maximum message size ever to be
 * used for communication (for both requests and replies) between client and
 * server during that session. If client suggests a 'msize' smaller than this
 * value then session is denied by server with an error response.
 */
#define P9_MIN_MSIZE    4096

#define P9_NOTAG    UINT16_MAX
#define P9_NOFID    UINT32_MAX
#define P9_MAXWELEM 16

#define FID_REFERENCED          0x1
#define FID_NON_RECLAIMABLE     0x2
static inline char *rpath(FsContext *ctx, const char *path)
{
    return g_strdup_printf("%s/%s", ctx->fs_root, path);
}

/*
 * ample room for Twrite/Rread header
 * size[4] Tread/Twrite tag[2] fid[4] offset[8] count[4]
 */
#define P9_IOHDRSZ 24

typedef struct V9fsPDU V9fsPDU;
typedef struct V9fsState V9fsState;
typedef struct V9fsTransport V9fsTransport;

typedef struct {
    uint32_t size_le;
    uint8_t id;
    uint16_t tag_le;
} QEMU_PACKED P9MsgHeader;
/* According to the specification, 9p messages start with a 7-byte header.
 * Since most of the code uses this header size in literal form, we must be
 * sure this is indeed the case.
 */
QEMU_BUILD_BUG_ON(sizeof(P9MsgHeader) != 7);

struct V9fsPDU {
    uint32_t size;
    uint16_t tag;
    uint8_t id;
    uint8_t cancelled;
    CoQueue complete;
    V9fsState *s;
    QLIST_ENTRY(V9fsPDU) next;
    uint32_t idx;
};


/* FIXME
 * 1) change user needs to set groups and stuff
 */

#define MAX_REQ         128
#define MAX_TAG_LEN     32

#define BUG_ON(cond) assert(!(cond))

typedef struct V9fsFidState V9fsFidState;

enum {
    P9_FID_NONE = 0,
    P9_FID_FILE,
    P9_FID_DIR,
    P9_FID_XATTR,
};

typedef struct V9fsConf
{
    /* tag name for the device */
    char *tag;
    char *fsdev_id;
} V9fsConf;

/* 9p2000.L xattr flags (matches Linux values) */
#define P9_XATTR_CREATE 1
#define P9_XATTR_REPLACE 2

typedef struct V9fsXattr
{
    uint64_t copied_len;
    uint64_t len;
    void *value;
    V9fsString name;
    int flags;
    bool xattrwalk_fid;
} V9fsXattr;

typedef struct V9fsDir {
    DIR *stream;
    P9ProtoVersion proto_version;
    /* readdir mutex type used for 9P2000.u protocol variant */
    CoMutex readdir_mutex_u;
    /* readdir mutex type used for 9P2000.L protocol variant */
    QemuMutex readdir_mutex_L;
} V9fsDir;

static inline void v9fs_readdir_lock(V9fsDir *dir)
{
    if (dir->proto_version == V9FS_PROTO_2000U) {
        qemu_co_mutex_lock(&dir->readdir_mutex_u);
    } else {
        qemu_mutex_lock(&dir->readdir_mutex_L);
    }
}

static inline void v9fs_readdir_unlock(V9fsDir *dir)
{
    if (dir->proto_version == V9FS_PROTO_2000U) {
        qemu_co_mutex_unlock(&dir->readdir_mutex_u);
    } else {
        qemu_mutex_unlock(&dir->readdir_mutex_L);
    }
}

static inline void v9fs_readdir_init(P9ProtoVersion proto_version, V9fsDir *dir)
{
    dir->proto_version = proto_version;
    if (proto_version == V9FS_PROTO_2000U) {
        qemu_co_mutex_init(&dir->readdir_mutex_u);
    } else {
        qemu_mutex_init(&dir->readdir_mutex_L);
    }
}

/**
 * Type for 9p fs drivers' (a.k.a. 9p backends) result of readdir requests,
 * which is a chained list of directory entries.
 */
typedef struct V9fsDirEnt {
    /* mandatory (must not be NULL) information for all readdir requests */
    struct dirent *dent;
    /*
     * optional (may be NULL): A full stat of each directory entry is just
     * done if explicitly told to fs driver.
     */
    struct stat *st;
    /*
     * instead of an array, directory entries are always returned as
     * chained list, that's because the amount of entries retrieved by fs
     * drivers is dependent on the individual entries' name (since response
     * messages are size limited), so the final amount cannot be estimated
     * before hand
     */
    struct V9fsDirEnt *next;
} V9fsDirEnt;

/*
 * Filled by fs driver on open and other
 * calls.
 */
union V9fsFidOpenState {
    int fd;
    V9fsDir dir;
    V9fsXattr xattr;
    /*
     * private pointer for fs drivers, that
     * have its own internal representation of
     * open files.
     */
    void *private;
};

struct V9fsFidState {
    int fid_type;
    int32_t fid;
    V9fsPath path;
    V9fsFidOpenState fs;
    V9fsFidOpenState fs_reclaim;
    int flags;
    int open_flags;
    uid_t uid;
    int ref;
    bool clunked;
    QSIMPLEQ_ENTRY(V9fsFidState) next;
    QSLIST_ENTRY(V9fsFidState) reclaim_next;
};

typedef enum AffixType_t {
    AffixType_Prefix,
    AffixType_Suffix, /* A.k.a. postfix. */
} AffixType_t;

/**
 * @brief Unique affix of variable length.
 *
 * An affix is (currently) either a suffix or a prefix, which is either
 * going to be prepended (prefix) or appended (suffix) with some other
 * number for the goal to generate unique numbers. Accordingly the
 * suffixes (or prefixes) we generate @b must all have the mathematical
 * property of being suffix-free (or prefix-free in case of prefixes)
 * so that no matter what number we concatenate the affix with, that we
 * always reliably get unique numbers as result after concatenation.
 */
typedef struct VariLenAffix {
    AffixType_t type; /* Whether this affix is a suffix or a prefix. */
    uint64_t value; /* Actual numerical value of this affix. */
    /*
     * Lenght of the affix, that is how many (of the lowest) bits of @c value
     * must be used for appending/prepending this affix to its final resulting,
     * unique number.
     */
    int bits;
} VariLenAffix;

/* See qid_inode_prefix_hash_bits(). */
typedef struct {
    dev_t dev; /* FS device on host. */
    /*
     * How many (high) bits of the original inode number shall be used for
     * hashing.
     */
    int prefix_bits;
} QpdEntry;

/* QID path prefix entry, see stat_to_qid */
typedef struct {
    dev_t dev;
    uint16_t ino_prefix;
    uint32_t qp_affix_index;
    VariLenAffix qp_affix;
} QppEntry;

/* QID path full entry, as above */
typedef struct {
    dev_t dev;
    ino_t ino;
    uint64_t path;
} QpfEntry;

struct V9fsState {
    QLIST_HEAD(, V9fsPDU) free_list;
    QLIST_HEAD(, V9fsPDU) active_list;
    QSIMPLEQ_HEAD(, V9fsFidState) fid_list;
    FileOperations *ops;
    FsContext ctx;
    char *tag;
    P9ProtoVersion proto_version;
    int32_t msize;
    V9fsPDU pdus[MAX_REQ];
    const V9fsTransport *transport;
    /*
     * lock ensuring atomic path update
     * on rename.
     */
    CoRwlock rename_lock;
    int32_t root_fid;
    Error *migration_blocker;
    V9fsConf fsconf;
    V9fsQID root_qid;
    dev_t dev_id;
    struct qht qpd_table;
    struct qht qpp_table;
    struct qht qpf_table;
    uint64_t qp_ndevices; /* Amount of entries in qpd_table. */
    uint16_t qp_affix_next;
    uint64_t qp_fullpath_next;
};

/* 9p2000.L open flags */
#define P9_DOTL_RDONLY        00000000
#define P9_DOTL_WRONLY        00000001
#define P9_DOTL_RDWR          00000002
#define P9_DOTL_NOACCESS      00000003
#define P9_DOTL_CREATE        00000100
#define P9_DOTL_EXCL          00000200
#define P9_DOTL_NOCTTY        00000400
#define P9_DOTL_TRUNC         00001000
#define P9_DOTL_APPEND        00002000
#define P9_DOTL_NONBLOCK      00004000
#define P9_DOTL_DSYNC         00010000
#define P9_DOTL_FASYNC        00020000
#define P9_DOTL_DIRECT        00040000
#define P9_DOTL_LARGEFILE     00100000
#define P9_DOTL_DIRECTORY     00200000
#define P9_DOTL_NOFOLLOW      00400000
#define P9_DOTL_NOATIME       01000000
#define P9_DOTL_CLOEXEC       02000000
#define P9_DOTL_SYNC          04000000

/* 9p2000.L at flags */
#define P9_DOTL_AT_REMOVEDIR         0x200

/* 9P2000.L lock type */
#define P9_LOCK_TYPE_RDLCK 0
#define P9_LOCK_TYPE_WRLCK 1
#define P9_LOCK_TYPE_UNLCK 2

#define P9_LOCK_SUCCESS 0
#define P9_LOCK_BLOCKED 1
#define P9_LOCK_ERROR 2
#define P9_LOCK_GRACE 3

#define P9_LOCK_FLAGS_BLOCK 1
#define P9_LOCK_FLAGS_RECLAIM 2

typedef struct V9fsFlock
{
    uint8_t type;
    uint32_t flags;
    uint64_t start; /* absolute offset */
    uint64_t length;
    uint32_t proc_id;
    V9fsString client_id;
} V9fsFlock;

typedef struct V9fsGetlock
{
    uint8_t type;
    uint64_t start; /* absolute offset */
    uint64_t length;
    uint32_t proc_id;
    V9fsString client_id;
} V9fsGetlock;

extern int open_fd_hw;
extern int total_open_fd;

static inline void v9fs_path_write_lock(V9fsState *s)
{
    if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
        qemu_co_rwlock_wrlock(&s->rename_lock);
    }
}

static inline void v9fs_path_read_lock(V9fsState *s)
{
    if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
        qemu_co_rwlock_rdlock(&s->rename_lock);
    }
}

static inline void v9fs_path_unlock(V9fsState *s)
{
    if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
        qemu_co_rwlock_unlock(&s->rename_lock);
    }
}

static inline uint8_t v9fs_request_cancelled(V9fsPDU *pdu)
{
    return pdu->cancelled;
}

void coroutine_fn v9fs_reclaim_fd(V9fsPDU *pdu);
void v9fs_path_init(V9fsPath *path);
void v9fs_path_free(V9fsPath *path);
void v9fs_path_sprintf(V9fsPath *path, const char *fmt, ...);
void v9fs_path_copy(V9fsPath *dst, const V9fsPath *src);
size_t v9fs_readdir_response_size(V9fsString *name);
int v9fs_name_to_path(V9fsState *s, V9fsPath *dirpath,
                      const char *name, V9fsPath *path);
int v9fs_device_realize_common(V9fsState *s, const V9fsTransport *t,
                               Error **errp);
void v9fs_device_unrealize_common(V9fsState *s);

V9fsPDU *pdu_alloc(V9fsState *s);
void pdu_free(V9fsPDU *pdu);
void pdu_submit(V9fsPDU *pdu, P9MsgHeader *hdr);
void v9fs_reset(V9fsState *s);

struct V9fsTransport {
    ssize_t     (*pdu_vmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt,
                                va_list ap);
    ssize_t     (*pdu_vunmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt,
                                  va_list ap);
    void        (*init_in_iov_from_pdu)(V9fsPDU *pdu, struct iovec **piov,
                                        unsigned int *pniov, size_t size);
    void        (*init_out_iov_from_pdu)(V9fsPDU *pdu, struct iovec **piov,
                                         unsigned int *pniov, size_t size);
    void        (*push_and_notify)(V9fsPDU *pdu);
};

#endif
Commit	Line	Data
2a6a4076 MA	1	#ifndef QEMU_9P_H
2a6a4076 MA	2	#define QEMU_9P_H
ebe74f8b	3
ebe74f8b	4	#include <dirent.h>
ebe74f8b WL	5	#include <utime.h>
ebe74f8b WL	6	#include <sys/resource.h>
ebe74f8b WL	7	#include "fsdev/file-op-9p.h"
	8	#include "fsdev/9p-iov-marshal.h"
	9	#include "qemu/thread.h"
	10	#include "qemu/coroutine.h"
1a6ed33c	11	#include "qemu/qht.h"
ebe74f8b WL	12
	13	enum {
	14	P9_TLERROR = 6,
	15	P9_RLERROR,
	16	P9_TSTATFS = 8,
	17	P9_RSTATFS,
	18	P9_TLOPEN = 12,
	19	P9_RLOPEN,
	20	P9_TLCREATE = 14,
	21	P9_RLCREATE,
	22	P9_TSYMLINK = 16,
	23	P9_RSYMLINK,
	24	P9_TMKNOD = 18,
	25	P9_RMKNOD,
	26	P9_TRENAME = 20,
	27	P9_RRENAME,
	28	P9_TREADLINK = 22,
	29	P9_RREADLINK,
	30	P9_TGETATTR = 24,
	31	P9_RGETATTR,
	32	P9_TSETATTR = 26,
	33	P9_RSETATTR,
	34	P9_TXATTRWALK = 30,
	35	P9_RXATTRWALK,
	36	P9_TXATTRCREATE = 32,
	37	P9_RXATTRCREATE,
	38	P9_TREADDIR = 40,
	39	P9_RREADDIR,
	40	P9_TFSYNC = 50,
	41	P9_RFSYNC,
	42	P9_TLOCK = 52,
	43	P9_RLOCK,
	44	P9_TGETLOCK = 54,
	45	P9_RGETLOCK,
	46	P9_TLINK = 70,
	47	P9_RLINK,
	48	P9_TMKDIR = 72,
	49	P9_RMKDIR,
	50	P9_TRENAMEAT = 74,
	51	P9_RRENAMEAT,
	52	P9_TUNLINKAT = 76,
	53	P9_RUNLINKAT,
	54	P9_TVERSION = 100,
	55	P9_RVERSION,
	56	P9_TAUTH = 102,
	57	P9_RAUTH,
	58	P9_TATTACH = 104,
	59	P9_RATTACH,
	60	P9_TERROR = 106,
	61	P9_RERROR,
	62	P9_TFLUSH = 108,
	63	P9_RFLUSH,
	64	P9_TWALK = 110,
	65	P9_RWALK,
	66	P9_TOPEN = 112,
	67	P9_ROPEN,
	68	P9_TCREATE = 114,
	69	P9_RCREATE,
	70	P9_TREAD = 116,
	71	P9_RREAD,
	72	P9_TWRITE = 118,
	73	P9_RWRITE,
	74	P9_TCLUNK = 120,
	75	P9_RCLUNK,
76	P9_TREMOVE = 122,
77	P9_RREMOVE,
78	P9_TSTAT = 124,
79	P9_RSTAT,
80	P9_TWSTAT = 126,
81	P9_RWSTAT,
82	};
83
84
85	/* qid.types */
86	enum {
87	P9_QTDIR = 0x80,
88	P9_QTAPPEND = 0x40,
89	P9_QTEXCL = 0x20,
90	P9_QTMOUNT = 0x10,
91	P9_QTAUTH = 0x08,
92	P9_QTTMP = 0x04,
93	P9_QTSYMLINK = 0x02,
94	P9_QTLINK = 0x01,
95	P9_QTFILE = 0x00,
96	};
97
8e71b96c	98	typedef enum P9ProtoVersion {
ebe74f8b WL	99	V9FS_PROTO_2000U = 0x01,
ebe74f8b WL	100	V9FS_PROTO_2000L = 0x02,
8e71b96c	101	} P9ProtoVersion;
ebe74f8b	102
e16453a3 CS	103	/**
	104	* @brief Minimum message size supported by this 9pfs server.
	105	*
	106	* A client establishes a session by sending a Tversion request along with a
	107	* 'msize' parameter which suggests the server a maximum message size ever to be
	108	* used for communication (for both requests and replies) between client and
	109	* server during that session. If client suggests a 'msize' smaller than this
	110	* value then session is denied by server with an error response.
	111	*/
	112	#define P9_MIN_MSIZE 4096
	113
baecbde6 GK	114	#define P9_NOTAG UINT16_MAX
baecbde6 GK	115	#define P9_NOFID UINT32_MAX
ebe74f8b WL	116	#define P9_MAXWELEM 16
	117
	118	#define FID_REFERENCED 0x1
	119	#define FID_NON_RECLAIMABLE 0x2
	120	static inline char rpath(FsContext ctx, const char *path)
	121	{
	122	return g_strdup_printf("%s/%s", ctx->fs_root, path);
	123	}
	124
	125	/*
	126	* ample room for Twrite/Rread header
	127	* size[4] Tread/Twrite tag[2] fid[4] offset[8] count[4]
	128	*/
	129	#define P9_IOHDRSZ 24
	130
	131	typedef struct V9fsPDU V9fsPDU;
21cf9edf	132	typedef struct V9fsState V9fsState;
8e71b96c	133	typedef struct V9fsTransport V9fsTransport;
ebe74f8b	134
c9fb47e7 SS	135	typedef struct {
	136	uint32_t size_le;
	137	uint8_t id;
	138	uint16_t tag_le;
	139	} QEMU_PACKED P9MsgHeader;
a4d99854 GK	140	/* According to the specification, 9p messages start with a 7-byte header.
	141	* Since most of the code uses this header size in literal form, we must be
	142	* sure this is indeed the case.
	143	*/
	144	QEMU_BUILD_BUG_ON(sizeof(P9MsgHeader) != 7);
c9fb47e7	145
487729e9	146	struct V9fsPDU {
ebe74f8b WL	147	uint32_t size;
	148	uint16_t tag;
	149	uint8_t id;
	150	uint8_t cancelled;
	151	CoQueue complete;
21cf9edf	152	V9fsState *s;
ebe74f8b	153	QLIST_ENTRY(V9fsPDU) next;
00588a0a	154	uint32_t idx;
ebe74f8b WL	155	};
	156
	157
	158	/* FIXME
	159	* 1) change user needs to set groups and stuff
	160	*/
	161
	162	#define MAX_REQ 128
	163	#define MAX_TAG_LEN 32
	164
	165	#define BUG_ON(cond) assert(!(cond))
	166
	167	typedef struct V9fsFidState V9fsFidState;
	168
	169	enum {
	170	P9_FID_NONE = 0,
	171	P9_FID_FILE,
	172	P9_FID_DIR,
	173	P9_FID_XATTR,
	174	};
	175
	176	typedef struct V9fsConf
	177	{
	178	/* tag name for the device */
	179	char *tag;
	180	char *fsdev_id;
	181	} V9fsConf;
	182
aca6897f KF	183	/* 9p2000.L xattr flags (matches Linux values) */
	184	#define P9_XATTR_CREATE 1
	185	#define P9_XATTR_REPLACE 2
	186
ebe74f8b WL	187	typedef struct V9fsXattr
ebe74f8b WL	188	{
8495f9ad LQ	189	uint64_t copied_len;
8495f9ad LQ	190	uint64_t len;
ebe74f8b WL	191	void *value;
	192	V9fsString name;
	193	int flags;
dd28fbbc	194	bool xattrwalk_fid;
ebe74f8b WL	195	} V9fsXattr;
ebe74f8b WL	196
f314ea4e GK	197	typedef struct V9fsDir {
f314ea4e GK	198	DIR *stream;
d2c5cf7c CS	199	P9ProtoVersion proto_version;
	200	/* readdir mutex type used for 9P2000.u protocol variant */
	201	CoMutex readdir_mutex_u;
	202	/* readdir mutex type used for 9P2000.L protocol variant */
	203	QemuMutex readdir_mutex_L;
f314ea4e GK	204	} V9fsDir;
f314ea4e GK	205
7cde47d4 GK	206	static inline void v9fs_readdir_lock(V9fsDir *dir)
7cde47d4 GK	207	{
d2c5cf7c CS	208	if (dir->proto_version == V9FS_PROTO_2000U) {
	209	qemu_co_mutex_lock(&dir->readdir_mutex_u);
	210	} else {
	211	qemu_mutex_lock(&dir->readdir_mutex_L);
	212	}
7cde47d4 GK	213	}
	214
	215	static inline void v9fs_readdir_unlock(V9fsDir *dir)
	216	{
d2c5cf7c CS	217	if (dir->proto_version == V9FS_PROTO_2000U) {
	218	qemu_co_mutex_unlock(&dir->readdir_mutex_u);
	219	} else {
	220	qemu_mutex_unlock(&dir->readdir_mutex_L);
	221	}
7cde47d4 GK	222	}
7cde47d4 GK	223
d2c5cf7c	224	static inline void v9fs_readdir_init(P9ProtoVersion proto_version, V9fsDir *dir)
7cde47d4	225	{
d2c5cf7c CS	226	dir->proto_version = proto_version;
	227	if (proto_version == V9FS_PROTO_2000U) {
	228	qemu_co_mutex_init(&dir->readdir_mutex_u);
	229	} else {
	230	qemu_mutex_init(&dir->readdir_mutex_L);
	231	}
7cde47d4 GK	232	}
7cde47d4 GK	233
2149675b CS	234	/**
	235	* Type for 9p fs drivers' (a.k.a. 9p backends) result of readdir requests,
	236	* which is a chained list of directory entries.
	237	*/
	238	typedef struct V9fsDirEnt {
	239	/* mandatory (must not be NULL) information for all readdir requests */
	240	struct dirent *dent;
	241	/*
	242	* optional (may be NULL): A full stat of each directory entry is just
	243	* done if explicitly told to fs driver.
	244	*/
	245	struct stat *st;
	246	/*
	247	* instead of an array, directory entries are always returned as
	248	* chained list, that's because the amount of entries retrieved by fs
	249	* drivers is dependent on the individual entries' name (since response
	250	* messages are size limited), so the final amount cannot be estimated
	251	* before hand
	252	*/
	253	struct V9fsDirEnt *next;
	254	} V9fsDirEnt;
	255
ebe74f8b WL	256	/*
	257	* Filled by fs driver on open and other
	258	* calls.
	259	*/
	260	union V9fsFidOpenState {
	261	int fd;
f314ea4e	262	V9fsDir dir;
ebe74f8b WL	263	V9fsXattr xattr;
	264	/*
	265	* private pointer for fs drivers, that
	266	* have its own internal representation of
	267	* open files.
	268	*/
	269	void *private;
	270	};
	271
487729e9	272	struct V9fsFidState {
ebe74f8b WL	273	int fid_type;
	274	int32_t fid;
	275	V9fsPath path;
	276	V9fsFidOpenState fs;
	277	V9fsFidOpenState fs_reclaim;
	278	int flags;
	279	int open_flags;
	280	uid_t uid;
	281	int ref;
2e53160f	282	bool clunked;
feabd6cf	283	QSIMPLEQ_ENTRY(V9fsFidState) next;
81f9766b	284	QSLIST_ENTRY(V9fsFidState) reclaim_next;
ebe74f8b WL	285	};
ebe74f8b WL	286
6b6aa828 CS	287	typedef enum AffixType_t {
	288	AffixType_Prefix,
	289	AffixType_Suffix, /* A.k.a. postfix. */
	290	} AffixType_t;
	291
	292	/**
	293	* @brief Unique affix of variable length.
	294	*
	295	* An affix is (currently) either a suffix or a prefix, which is either
	296	* going to be prepended (prefix) or appended (suffix) with some other
	297	* number for the goal to generate unique numbers. Accordingly the
	298	* suffixes (or prefixes) we generate @b must all have the mathematical
	299	* property of being suffix-free (or prefix-free in case of prefixes)
	300	* so that no matter what number we concatenate the affix with, that we
	301	* always reliably get unique numbers as result after concatenation.
	302	*/
	303	typedef struct VariLenAffix {
	304	AffixType_t type; /* Whether this affix is a suffix or a prefix. */
	305	uint64_t value; /* Actual numerical value of this affix. */
	306	/*
	307	* Lenght of the affix, that is how many (of the lowest) bits of @c value
	308	* must be used for appending/prepending this affix to its final resulting,
	309	* unique number.
	310	*/
	311	int bits;
	312	} VariLenAffix;
	313
	314	/* See qid_inode_prefix_hash_bits(). */
	315	typedef struct {
	316	dev_t dev; /* FS device on host. */
	317	/*
	318	* How many (high) bits of the original inode number shall be used for
	319	* hashing.
	320	*/
	321	int prefix_bits;
	322	} QpdEntry;
1a6ed33c AM	323
	324	/* QID path prefix entry, see stat_to_qid */
	325	typedef struct {
	326	dev_t dev;
	327	uint16_t ino_prefix;
6b6aa828 CS	328	uint32_t qp_affix_index;
6b6aa828 CS	329	VariLenAffix qp_affix;
1a6ed33c AM	330	} QppEntry;
1a6ed33c AM	331
f3fe4a2d AM	332	/* QID path full entry, as above */
	333	typedef struct {
	334	dev_t dev;
	335	ino_t ino;
	336	uint64_t path;
	337	} QpfEntry;
	338
487729e9	339	struct V9fsState {
ebe74f8b WL	340	QLIST_HEAD(, V9fsPDU) free_list;
ebe74f8b WL	341	QLIST_HEAD(, V9fsPDU) active_list;
feabd6cf	342	QSIMPLEQ_HEAD(, V9fsFidState) fid_list;
ebe74f8b WL	343	FileOperations *ops;
	344	FsContext ctx;
	345	char *tag;
8e71b96c	346	P9ProtoVersion proto_version;
ebe74f8b	347	int32_t msize;
583f21f8	348	V9fsPDU pdus[MAX_REQ];
8e71b96c	349	const V9fsTransport *transport;
ebe74f8b WL	350	/*
	351	* lock ensuring atomic path update
	352	* on rename.
	353	*/
	354	CoRwlock rename_lock;
	355	int32_t root_fid;
	356	Error *migration_blocker;
	357	V9fsConf fsconf;
56f101ec	358	V9fsQID root_qid;
3b5ee9e8	359	dev_t dev_id;
6b6aa828	360	struct qht qpd_table;
1a6ed33c	361	struct qht qpp_table;
f3fe4a2d	362	struct qht qpf_table;
6b6aa828 CS	363	uint64_t qp_ndevices; /* Amount of entries in qpd_table. */
6b6aa828 CS	364	uint16_t qp_affix_next;
f3fe4a2d	365	uint64_t qp_fullpath_next;
21cf9edf	366	};
ebe74f8b WL	367
	368	/* 9p2000.L open flags */
	369	#define P9_DOTL_RDONLY 00000000
	370	#define P9_DOTL_WRONLY 00000001
	371	#define P9_DOTL_RDWR 00000002
	372	#define P9_DOTL_NOACCESS 00000003
	373	#define P9_DOTL_CREATE 00000100
	374	#define P9_DOTL_EXCL 00000200
	375	#define P9_DOTL_NOCTTY 00000400
	376	#define P9_DOTL_TRUNC 00001000
	377	#define P9_DOTL_APPEND 00002000
	378	#define P9_DOTL_NONBLOCK 00004000
	379	#define P9_DOTL_DSYNC 00010000
	380	#define P9_DOTL_FASYNC 00020000
	381	#define P9_DOTL_DIRECT 00040000
	382	#define P9_DOTL_LARGEFILE 00100000
	383	#define P9_DOTL_DIRECTORY 00200000
	384	#define P9_DOTL_NOFOLLOW 00400000
	385	#define P9_DOTL_NOATIME 01000000
	386	#define P9_DOTL_CLOEXEC 02000000
	387	#define P9_DOTL_SYNC 04000000
	388
	389	/* 9p2000.L at flags */
	390	#define P9_DOTL_AT_REMOVEDIR 0x200
	391
	392	/* 9P2000.L lock type */
	393	#define P9_LOCK_TYPE_RDLCK 0
	394	#define P9_LOCK_TYPE_WRLCK 1
	395	#define P9_LOCK_TYPE_UNLCK 2
	396
	397	#define P9_LOCK_SUCCESS 0
	398	#define P9_LOCK_BLOCKED 1
	399	#define P9_LOCK_ERROR 2
	400	#define P9_LOCK_GRACE 3
	401
	402	#define P9_LOCK_FLAGS_BLOCK 1
	403	#define P9_LOCK_FLAGS_RECLAIM 2
	404
	405	typedef struct V9fsFlock
	406	{
	407	uint8_t type;
	408	uint32_t flags;
	409	uint64_t start; /* absolute offset */
	410	uint64_t length;
	411	uint32_t proc_id;
	412	V9fsString client_id;
	413	} V9fsFlock;
	414
	415	typedef struct V9fsGetlock
	416	{
	417	uint8_t type;
	418	uint64_t start; /* absolute offset */
	419	uint64_t length;
	420	uint32_t proc_id;
	421	V9fsString client_id;
	422	} V9fsGetlock;
	423
	424	extern int open_fd_hw;
	425	extern int total_open_fd;
	426
	427	static inline void v9fs_path_write_lock(V9fsState *s)
	428	{
	429	if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
	430	qemu_co_rwlock_wrlock(&s->rename_lock);
431	}
432	}
433
434	static inline void v9fs_path_read_lock(V9fsState *s)
435	{
436	if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
437	qemu_co_rwlock_rdlock(&s->rename_lock);
438	}
439	}
440
441	static inline void v9fs_path_unlock(V9fsState *s)
442	{
443	if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
444	qemu_co_rwlock_unlock(&s->rename_lock);
445	}
446	}
447
448	static inline uint8_t v9fs_request_cancelled(V9fsPDU *pdu)
449	{
450	return pdu->cancelled;
451	}
452
8440e22e	453	void coroutine_fn v9fs_reclaim_fd(V9fsPDU *pdu);
bc70a592 GK	454	void v9fs_path_init(V9fsPath *path);
	455	void v9fs_path_free(V9fsPath *path);
	456	void v9fs_path_sprintf(V9fsPath path, const char fmt, ...);
e446a1eb	457	void v9fs_path_copy(V9fsPath dst, const V9fsPath src);
29c9d2ca	458	size_t v9fs_readdir_response_size(V9fsString *name);
bc70a592 GK	459	int v9fs_name_to_path(V9fsState s, V9fsPath dirpath,
bc70a592 GK	460	const char name, V9fsPath path);
066eb006 GK	461	int v9fs_device_realize_common(V9fsState s, const V9fsTransport t,
066eb006 GK	462	Error **errp);
b69c3c21	463	void v9fs_device_unrealize_common(V9fsState *s);
ebe74f8b	464
4b311c5f WL	465	V9fsPDU pdu_alloc(V9fsState s);
4b311c5f WL	466	void pdu_free(V9fsPDU *pdu);
506f3275	467	void pdu_submit(V9fsPDU pdu, P9MsgHeader hdr);
0e44a0fd	468	void v9fs_reset(V9fsState *s);
ebe74f8b	469
ea83441c SS	470	struct V9fsTransport {
	471	ssize_t (pdu_vmarshal)(V9fsPDU pdu, size_t offset, const char *fmt,
	472	va_list ap);
	473	ssize_t (pdu_vunmarshal)(V9fsPDU pdu, size_t offset, const char *fmt,
	474	va_list ap);
88da0b03	475	void (init_in_iov_from_pdu)(V9fsPDU pdu, struct iovec **piov,
cf45183b	476	unsigned int *pniov, size_t size);
88da0b03	477	void (init_out_iov_from_pdu)(V9fsPDU pdu, struct iovec **piov,
8d37de41	478	unsigned int *pniov, size_t size);
ea83441c SS	479	void (push_and_notify)(V9fsPDU pdu);
	480	};
	481
ebe74f8b	482	#endif