#ifndef QEMU_9P_H #define QEMU_9P_H #include #include #include #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 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; /* * 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 ``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; 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 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); }; #if defined(XATTR_SIZE_MAX) /* Linux */ #define P9_XATTR_SIZE_MAX XATTR_SIZE_MAX #elif defined(CONFIG_DARWIN) /* * Darwin doesn't seem to define a maximum xattr size in its user * space header, so manually configure it across platforms as 64k. * * Having no limit at all can lead to QEMU crashing during large g_malloc() * calls. Because QEMU does not currently support macOS guests, the below * preliminary solution only works due to its being a reflection of the limit of * Linux guests. */ #define P9_XATTR_SIZE_MAX 65536 #else #error Missing definition for P9_XATTR_SIZE_MAX for this host system #endif #endif