LXR qemu/hw/9pfs/9p.h

   1#ifndef QEMU_9P_H
   2#define QEMU_9P_H
   3
   4#include <dirent.h>
   5#include <utime.h>
   6#include <sys/resource.h>
   7#include "fsdev/file-op-9p.h"
   8#include "fsdev/9p-iov-marshal.h"
   9#include "qemu/thread.h"
  10#include "qemu/coroutine.h"
  11#include "qemu/qht.h"
  12
  13enum {
  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 */
  86enum {
  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
  98typedef enum P9ProtoVersion {
  99    V9FS_PROTO_2000U = 0x01,
 100    V9FS_PROTO_2000L = 0x02,
 101} P9ProtoVersion;
 102
 103#define P9_NOTAG    UINT16_MAX
 104#define P9_NOFID    UINT32_MAX
 105#define P9_MAXWELEM 16
 106
 107#define FID_REFERENCED          0x1
 108#define FID_NON_RECLAIMABLE     0x2
 109static inline char *rpath(FsContext *ctx, const char *path)
 110{
 111    return g_strdup_printf("%s/%s", ctx->fs_root, path);
 112}
 113
 114/*
 115 * ample room for Twrite/Rread header
 116 * size[4] Tread/Twrite tag[2] fid[4] offset[8] count[4]
 117 */
 118#define P9_IOHDRSZ 24
 119
 120typedef struct V9fsPDU V9fsPDU;
 121typedef struct V9fsState V9fsState;
 122typedef struct V9fsTransport V9fsTransport;
 123
 124typedef struct {
 125    uint32_t size_le;
 126    uint8_t id;
 127    uint16_t tag_le;
 128} QEMU_PACKED P9MsgHeader;
 129/* According to the specification, 9p messages start with a 7-byte header.
 130 * Since most of the code uses this header size in literal form, we must be
 131 * sure this is indeed the case.
 132 */
 133QEMU_BUILD_BUG_ON(sizeof(P9MsgHeader) != 7);
 134
 135struct V9fsPDU
 136{
 137    uint32_t size;
 138    uint16_t tag;
 139    uint8_t id;
 140    uint8_t cancelled;
 141    CoQueue complete;
 142    V9fsState *s;
 143    QLIST_ENTRY(V9fsPDU) next;
 144    uint32_t idx;
 145};
 146
 147
 148/* FIXME
 149 * 1) change user needs to set groups and stuff
 150 */
 151
 152#define MAX_REQ         128
 153#define MAX_TAG_LEN     32
 154
 155#define BUG_ON(cond) assert(!(cond))
 156
 157typedef struct V9fsFidState V9fsFidState;
 158
 159enum {
 160    P9_FID_NONE = 0,
 161    P9_FID_FILE,
 162    P9_FID_DIR,
 163    P9_FID_XATTR,
 164};
 165
 166typedef struct V9fsConf
 167{
 168    /* tag name for the device */
 169    char *tag;
 170    char *fsdev_id;
 171} V9fsConf;
 172
 173/* 9p2000.L xattr flags (matches Linux values) */
 174#define P9_XATTR_CREATE 1
 175#define P9_XATTR_REPLACE 2
 176
 177typedef struct V9fsXattr
 178{
 179    uint64_t copied_len;
 180    uint64_t len;
 181    void *value;
 182    V9fsString name;
 183    int flags;
 184    bool xattrwalk_fid;
 185} V9fsXattr;
 186
 187typedef struct V9fsDir {
 188    DIR *stream;
 189    CoMutex readdir_mutex;
 190} V9fsDir;
 191
 192static inline void v9fs_readdir_lock(V9fsDir *dir)
 193{
 194    qemu_co_mutex_lock(&dir->readdir_mutex);
 195}
 196
 197static inline void v9fs_readdir_unlock(V9fsDir *dir)
 198{
 199    qemu_co_mutex_unlock(&dir->readdir_mutex);
 200}
 201
 202static inline void v9fs_readdir_init(V9fsDir *dir)
 203{
 204    qemu_co_mutex_init(&dir->readdir_mutex);
 205}
 206
 207/*
 208 * Filled by fs driver on open and other
 209 * calls.
 210 */
 211union V9fsFidOpenState {
 212    int fd;
 213    V9fsDir dir;
 214    V9fsXattr xattr;
 215    /*
 216     * private pointer for fs drivers, that
 217     * have its own internal representation of
 218     * open files.
 219     */
 220    void *private;
 221};
 222
 223struct V9fsFidState
 224{
 225    int fid_type;
 226    int32_t fid;
 227    V9fsPath path;
 228    V9fsFidOpenState fs;
 229    V9fsFidOpenState fs_reclaim;
 230    int flags;
 231    int open_flags;
 232    uid_t uid;
 233    int ref;
 234    int clunked;
 235    V9fsFidState *next;
 236    V9fsFidState *rclm_lst;
 237};
 238
 239typedef enum AffixType_t {
 240    AffixType_Prefix,
 241    AffixType_Suffix, /* A.k.a. postfix. */
 242} AffixType_t;
 243
 244/**
 245 * @brief Unique affix of variable length.
 246 *
 247 * An affix is (currently) either a suffix or a prefix, which is either
 248 * going to be prepended (prefix) or appended (suffix) with some other
 249 * number for the goal to generate unique numbers. Accordingly the
 250 * suffixes (or prefixes) we generate @b must all have the mathematical
 251 * property of being suffix-free (or prefix-free in case of prefixes)
 252 * so that no matter what number we concatenate the affix with, that we
 253 * always reliably get unique numbers as result after concatenation.
 254 */
 255typedef struct VariLenAffix {
 256    AffixType_t type; /* Whether this affix is a suffix or a prefix. */
 257    uint64_t value; /* Actual numerical value of this affix. */
 258    /*
 259     * Lenght of the affix, that is how many (of the lowest) bits of @c value
 260     * must be used for appending/prepending this affix to its final resulting,
 261     * unique number.
 262     */
 263    int bits;
 264} VariLenAffix;
 265
 266/* See qid_inode_prefix_hash_bits(). */
 267typedef struct {
 268    dev_t dev; /* FS device on host. */
 269    /*
 270     * How many (high) bits of the original inode number shall be used for
 271     * hashing.
 272     */
 273    int prefix_bits;
 274} QpdEntry;
 275
 276/* QID path prefix entry, see stat_to_qid */
 277typedef struct {
 278    dev_t dev;
 279    uint16_t ino_prefix;
 280    uint32_t qp_affix_index;
 281    VariLenAffix qp_affix;
 282} QppEntry;
 283
 284/* QID path full entry, as above */
 285typedef struct {
 286    dev_t dev;
 287    ino_t ino;
 288    uint64_t path;
 289} QpfEntry;
 290
 291struct V9fsState
 292{
 293    QLIST_HEAD(, V9fsPDU) free_list;
 294    QLIST_HEAD(, V9fsPDU) active_list;
 295    V9fsFidState *fid_list;
 296    FileOperations *ops;
 297    FsContext ctx;
 298    char *tag;
 299    P9ProtoVersion proto_version;
 300    int32_t msize;
 301    V9fsPDU pdus[MAX_REQ];
 302    const V9fsTransport *transport;
 303    /*
 304     * lock ensuring atomic path update
 305     * on rename.
 306     */
 307    CoRwlock rename_lock;
 308    int32_t root_fid;
 309    Error *migration_blocker;
 310    V9fsConf fsconf;
 311    V9fsQID root_qid;
 312    dev_t dev_id;
 313    struct qht qpd_table;
 314    struct qht qpp_table;
 315    struct qht qpf_table;
 316    uint64_t qp_ndevices; /* Amount of entries in qpd_table. */
 317    uint16_t qp_affix_next;
 318    uint64_t qp_fullpath_next;
 319};
 320
 321/* 9p2000.L open flags */
 322#define P9_DOTL_RDONLY        00000000
 323#define P9_DOTL_WRONLY        00000001
 324#define P9_DOTL_RDWR          00000002
 325#define P9_DOTL_NOACCESS      00000003
 326#define P9_DOTL_CREATE        00000100
 327#define P9_DOTL_EXCL          00000200
 328#define P9_DOTL_NOCTTY        00000400
 329#define P9_DOTL_TRUNC         00001000
 330#define P9_DOTL_APPEND        00002000
 331#define P9_DOTL_NONBLOCK      00004000
 332#define P9_DOTL_DSYNC         00010000
 333#define P9_DOTL_FASYNC        00020000
 334#define P9_DOTL_DIRECT        00040000
 335#define P9_DOTL_LARGEFILE     00100000
 336#define P9_DOTL_DIRECTORY     00200000
 337#define P9_DOTL_NOFOLLOW      00400000
 338#define P9_DOTL_NOATIME       01000000
 339#define P9_DOTL_CLOEXEC       02000000
 340#define P9_DOTL_SYNC          04000000
 341
 342/* 9p2000.L at flags */
 343#define P9_DOTL_AT_REMOVEDIR         0x200
 344
 345/* 9P2000.L lock type */
 346#define P9_LOCK_TYPE_RDLCK 0
 347#define P9_LOCK_TYPE_WRLCK 1
 348#define P9_LOCK_TYPE_UNLCK 2
 349
 350#define P9_LOCK_SUCCESS 0
 351#define P9_LOCK_BLOCKED 1
 352#define P9_LOCK_ERROR 2
 353#define P9_LOCK_GRACE 3
 354
 355#define P9_LOCK_FLAGS_BLOCK 1
 356#define P9_LOCK_FLAGS_RECLAIM 2
 357
 358typedef struct V9fsFlock
 359{
 360    uint8_t type;
 361    uint32_t flags;
 362    uint64_t start; /* absolute offset */
 363    uint64_t length;
 364    uint32_t proc_id;
 365    V9fsString client_id;
 366} V9fsFlock;
 367
 368typedef struct V9fsGetlock
 369{
 370    uint8_t type;
 371    uint64_t start; /* absolute offset */
 372    uint64_t length;
 373    uint32_t proc_id;
 374    V9fsString client_id;
 375} V9fsGetlock;
 376
 377extern int open_fd_hw;
 378extern int total_open_fd;
 379
 380static inline void v9fs_path_write_lock(V9fsState *s)
 381{
 382    if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
 383        qemu_co_rwlock_wrlock(&s->rename_lock);
 384    }
 385}
 386
 387static inline void v9fs_path_read_lock(V9fsState *s)
 388{
 389    if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
 390        qemu_co_rwlock_rdlock(&s->rename_lock);
 391    }
 392}
 393
 394static inline void v9fs_path_unlock(V9fsState *s)
 395{
 396    if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
 397        qemu_co_rwlock_unlock(&s->rename_lock);
 398    }
 399}
 400
 401static inline uint8_t v9fs_request_cancelled(V9fsPDU *pdu)
 402{
 403    return pdu->cancelled;
 404}
 405
 406void coroutine_fn v9fs_reclaim_fd(V9fsPDU *pdu);
 407void v9fs_path_init(V9fsPath *path);
 408void v9fs_path_free(V9fsPath *path);
 409void v9fs_path_sprintf(V9fsPath *path, const char *fmt, ...);
 410void v9fs_path_copy(V9fsPath *dst, const V9fsPath *src);
 411int v9fs_name_to_path(V9fsState *s, V9fsPath *dirpath,
 412                      const char *name, V9fsPath *path);
 413int v9fs_device_realize_common(V9fsState *s, const V9fsTransport *t,
 414                               Error **errp);
 415void v9fs_device_unrealize_common(V9fsState *s, Error **errp);
 416
 417V9fsPDU *pdu_alloc(V9fsState *s);
 418void pdu_free(V9fsPDU *pdu);
 419void pdu_submit(V9fsPDU *pdu, P9MsgHeader *hdr);
 420void v9fs_reset(V9fsState *s);
 421
 422struct V9fsTransport {
 423    ssize_t     (*pdu_vmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt,
 424                                va_list ap);
 425    ssize_t     (*pdu_vunmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt,
 426                                  va_list ap);
 427    void        (*init_in_iov_from_pdu)(V9fsPDU *pdu, struct iovec **piov,
 428                                        unsigned int *pniov, size_t size);
 429    void        (*init_out_iov_from_pdu)(V9fsPDU *pdu, struct iovec **piov,
 430                                         unsigned int *pniov, size_t size);
 431    void        (*push_and_notify)(V9fsPDU *pdu);
 432};
 433
 434#endif
 435