qemu/hw/9pfs/9p.h
Michael Tokarev 28cbbdd28e hw/9pfs: spelling fixes
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2023-07-25 17:15:47 +03:00

486 lines
12 KiB
C

#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;
/*
* 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 coroutine_fn 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 coroutine_fn 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;
/*
* 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. */
/*
* Length of the affix, that is how many (of the lowest) bits of ``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;
GHashTable *fids;
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;
struct stat root_st;
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 coroutine_fn
v9fs_path_write_lock(V9fsState *s)
{
if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
qemu_co_rwlock_wrlock(&s->rename_lock);
}
}
static inline void coroutine_fn
v9fs_path_read_lock(V9fsState *s)
{
if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
qemu_co_rwlock_rdlock(&s->rename_lock);
}
}
static inline void coroutine_fn
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