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-rw-r--r--hw/9pfs/9p.h482
1 files changed, 482 insertions, 0 deletions
diff --git a/hw/9pfs/9p.h b/hw/9pfs/9p.h
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index 000000000..1567b6784
--- /dev/null
+++ b/hw/9pfs/9p.h
@@ -0,0 +1,482 @@
+#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;
+ 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);
+};
+
+#endif