9pfs: drop useless check in pdu_free()

[mirror_qemu.git] / hw / 9pfs / 9p.c

diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
index 51c6f9883bf8767df9e07f858da0a73f0b51d482..df8aa726c9a19743d854a16c82196175814f09d7 100644 (file)
--- a/hw/9pfs/9p.c
+++ b/hw/9pfs/9p.c
@@ -12,6 +12,7 @@
  */
 
 #include "qemu/osdep.h"
+#include <glib/gprintf.h>
 #include "hw/virtio/virtio.h"
 #include "qapi/error.h"
 #include "qemu/error-report.h"
@@ -179,6 +180,20 @@ void v9fs_path_free(V9fsPath *path)
     path->size = 0;
 }
 
+
+void GCC_FMT_ATTR(2, 3)
+v9fs_path_sprintf(V9fsPath *path, const char *fmt, ...)
+{
+    va_list ap;
+
+    v9fs_path_free(path);
+
+    va_start(ap, fmt);
+    /* Bump the size for including terminating NULL */
+    path->size = g_vasprintf(&path->data, fmt, ap) + 1;
+    va_end(ap);
+}
+
 void v9fs_path_copy(V9fsPath *lhs, V9fsPath *rhs)
 {
     v9fs_path_free(lhs);
@@ -221,7 +236,7 @@ static size_t v9fs_string_size(V9fsString *str)
 
 /*
  * returns 0 if fid got re-opened, 1 if not, < 0 on error */
-static int v9fs_reopen_fid(V9fsPDU *pdu, V9fsFidState *f)
+static int coroutine_fn v9fs_reopen_fid(V9fsPDU *pdu, V9fsFidState *f)
 {
     int err = 1;
     if (f->fid_type == P9_FID_FILE) {
@@ -240,7 +255,7 @@ static int v9fs_reopen_fid(V9fsPDU *pdu, V9fsFidState *f)
     return err;
 }
 
-static V9fsFidState *get_fid(V9fsPDU *pdu, int32_t fid)
+static V9fsFidState *coroutine_fn get_fid(V9fsPDU *pdu, int32_t fid)
 {
     int err;
     V9fsFidState *f;
@@ -306,7 +321,7 @@ static V9fsFidState *alloc_fid(V9fsState *s, int32_t fid)
     return f;
 }
 
-static int v9fs_xattr_fid_clunk(V9fsPDU *pdu, V9fsFidState *fidp)
+static int coroutine_fn v9fs_xattr_fid_clunk(V9fsPDU *pdu, V9fsFidState *fidp)
 {
     int retval = 0;
 
@@ -338,7 +353,7 @@ free_value:
     return retval;
 }
 
-static int free_fid(V9fsPDU *pdu, V9fsFidState *fidp)
+static int coroutine_fn free_fid(V9fsPDU *pdu, V9fsFidState *fidp)
 {
     int retval = 0;
 
@@ -359,7 +374,7 @@ static int free_fid(V9fsPDU *pdu, V9fsFidState *fidp)
     return retval;
 }
 
-static int put_fid(V9fsPDU *pdu, V9fsFidState *fidp)
+static int coroutine_fn put_fid(V9fsPDU *pdu, V9fsFidState *fidp)
 {
     BUG_ON(!fidp->ref);
     fidp->ref--;
@@ -403,7 +418,7 @@ static V9fsFidState *clunk_fid(V9fsState *s, int32_t fid)
     return fidp;
 }
 
-void v9fs_reclaim_fd(V9fsPDU *pdu)
+void coroutine_fn v9fs_reclaim_fd(V9fsPDU *pdu)
 {
     int reclaim_count = 0;
     V9fsState *s = pdu->s;
@@ -484,7 +499,7 @@ void v9fs_reclaim_fd(V9fsPDU *pdu)
     }
 }
 
-static int v9fs_mark_fids_unreclaim(V9fsPDU *pdu, V9fsPath *path)
+static int coroutine_fn v9fs_mark_fids_unreclaim(V9fsPDU *pdu, V9fsPath *path)
 {
     int err;
     V9fsState *s = pdu->s;
@@ -517,7 +532,7 @@ static int v9fs_mark_fids_unreclaim(V9fsPDU *pdu, V9fsPath *path)
     return 0;
 }
 
-static void virtfs_reset(V9fsPDU *pdu)
+static void coroutine_fn virtfs_reset(V9fsPDU *pdu)
 {
     V9fsState *s = pdu->s;
     V9fsFidState *fidp = NULL;
@@ -583,7 +598,8 @@ static void stat_to_qid(const struct stat *stbuf, V9fsQID *qidp)
     }
 }
 
-static int fid_to_qid(V9fsPDU *pdu, V9fsFidState *fidp, V9fsQID *qidp)
+static int coroutine_fn fid_to_qid(V9fsPDU *pdu, V9fsFidState *fidp,
+                                   V9fsQID *qidp)
 {
     struct stat stbuf;
     int err;
@@ -610,16 +626,14 @@ V9fsPDU *pdu_alloc(V9fsState *s)
 
 void pdu_free(V9fsPDU *pdu)
 {
-    if (pdu) {
-        V9fsState *s = pdu->s;
-        /*
-         * Cancelled pdu are added back to the freelist
-         * by flush request .
-         */
-        if (!pdu->cancelled) {
-            QLIST_REMOVE(pdu, next);
-            QLIST_INSERT_HEAD(&s->free_list, pdu, next);
-        }
+    V9fsState *s = pdu->s;
+    /*
+     * Cancelled pdu are added back to the freelist
+     * by flush request .
+     */
+    if (!pdu->cancelled) {
+        QLIST_REMOVE(pdu, next);
+        QLIST_INSERT_HEAD(&s->free_list, pdu, next);
     }
 }
 
@@ -628,7 +642,7 @@ void pdu_free(V9fsPDU *pdu)
  * because we always expect to have enough space to encode
  * error details
  */
-static void pdu_complete(V9fsPDU *pdu, ssize_t len)
+static void coroutine_fn pdu_complete(V9fsPDU *pdu, ssize_t len)
 {
     int8_t id = pdu->id + 1; /* Response */
     V9fsState *s = pdu->s;
@@ -795,9 +809,9 @@ static uint32_t stat_to_v9mode(const struct stat *stbuf)
     return mode;
 }
 
-static int stat_to_v9stat(V9fsPDU *pdu, V9fsPath *name,
-                            const struct stat *stbuf,
-                            V9fsStat *v9stat)
+static int coroutine_fn stat_to_v9stat(V9fsPDU *pdu, V9fsPath *name,
+                                       const struct stat *stbuf,
+                                       V9fsStat *v9stat)
 {
     int err;
     const char *str;
@@ -810,15 +824,15 @@ static int stat_to_v9stat(V9fsPDU *pdu, V9fsPath *name,
     v9stat->mtime = stbuf->st_mtime;
     v9stat->length = stbuf->st_size;
 
-    v9fs_string_null(&v9stat->uid);
-    v9fs_string_null(&v9stat->gid);
-    v9fs_string_null(&v9stat->muid);
+    v9fs_string_free(&v9stat->uid);
+    v9fs_string_free(&v9stat->gid);
+    v9fs_string_free(&v9stat->muid);
 
     v9stat->n_uid = stbuf->st_uid;
     v9stat->n_gid = stbuf->st_gid;
     v9stat->n_muid = 0;
 
-    v9fs_string_null(&v9stat->extension);
+    v9fs_string_free(&v9stat->extension);
 
     if (v9stat->mode & P9_STAT_MODE_SYMLINK) {
         err = v9fs_co_readlink(pdu, name, &v9stat->extension);
@@ -917,10 +931,8 @@ static void v9fs_fix_path(V9fsPath *dst, V9fsPath *src, int len)
     V9fsPath str;
     v9fs_path_init(&str);
     v9fs_path_copy(&str, dst);
-    v9fs_string_sprintf((V9fsString *)dst, "%s%s", src->data, str.data+len);
+    v9fs_path_sprintf(dst, "%s%s", src->data, str.data + len);
     v9fs_path_free(&str);
-    /* +1 to include terminating NULL */
-    dst->size++;
 }
 
 static inline bool is_ro_export(FsContext *ctx)
@@ -928,7 +940,7 @@ static inline bool is_ro_export(FsContext *ctx)
     return ctx->export_flags & V9FS_RDONLY;
 }
 
-static void v9fs_version(void *opaque)
+static void coroutine_fn v9fs_version(void *opaque)
 {
     ssize_t err;
     V9fsPDU *pdu = opaque;
@@ -966,7 +978,7 @@ out:
     v9fs_string_free(&version);
 }
 
-static void v9fs_attach(void *opaque)
+static void coroutine_fn v9fs_attach(void *opaque)
 {
     V9fsPDU *pdu = opaque;
     V9fsState *s = pdu->s;
@@ -1010,6 +1022,7 @@ static void v9fs_attach(void *opaque)
         goto out;
     }
     err += offset;
+    memcpy(&s->root_qid, &qid, sizeof(qid));
     trace_v9fs_attach_return(pdu->tag, pdu->id,
                              qid.type, qid.version, qid.path);
     /*
@@ -1031,7 +1044,7 @@ out_nofid:
     v9fs_string_free(&aname);
 }
 
-static void v9fs_stat(void *opaque)
+static void coroutine_fn v9fs_stat(void *opaque)
 {
     int32_t fid;
     V9fsStat v9stat;
@@ -1075,7 +1088,7 @@ out_nofid:
     pdu_complete(pdu, err);
 }
 
-static void v9fs_getattr(void *opaque)
+static void coroutine_fn v9fs_getattr(void *opaque)
 {
     int32_t fid;
     size_t offset = 7;
@@ -1151,7 +1164,7 @@ out_nofid:
 
 #define P9_ATTR_MASK    127
 
-static void v9fs_setattr(void *opaque)
+static void coroutine_fn v9fs_setattr(void *opaque)
 {
     int err = 0;
     int32_t fid;
@@ -1261,7 +1274,15 @@ static bool name_is_illegal(const char *name)
     return !*name || strchr(name, '/') != NULL;
 }
 
-static void v9fs_walk(void *opaque)
+static bool not_same_qid(const V9fsQID *qid1, const V9fsQID *qid2)
+{
+    return
+        qid1->type != qid2->type ||
+        qid1->version != qid2->version ||
+        qid1->path != qid2->path;
+}
+
+static void coroutine_fn v9fs_walk(void *opaque)
 {
     int name_idx;
     V9fsQID *qids = NULL;
@@ -1276,6 +1297,7 @@ static void v9fs_walk(void *opaque)
     V9fsFidState *newfidp = NULL;
     V9fsPDU *pdu = opaque;
     V9fsState *s = pdu->s;
+    V9fsQID qid;
 
     err = pdu_unmarshal(pdu, offset, "ddw", &fid, &newfid, &nwnames);
     if (err < 0) {
@@ -1309,8 +1331,15 @@ static void v9fs_walk(void *opaque)
         err = -ENOENT;
         goto out_nofid;
     }
+
     v9fs_path_init(&dpath);
     v9fs_path_init(&path);
+
+    err = fid_to_qid(pdu, fidp, &qid);
+    if (err < 0) {
+        goto out;
+    }
+
     /*
      * Both dpath and path initially poin to fidp.
      * Needed to handle request with nwnames == 0
@@ -1318,16 +1347,22 @@ static void v9fs_walk(void *opaque)
     v9fs_path_copy(&dpath, &fidp->path);
     v9fs_path_copy(&path, &fidp->path);
     for (name_idx = 0; name_idx < nwnames; name_idx++) {
-        err = v9fs_co_name_to_path(pdu, &dpath, wnames[name_idx].data, &path);
-        if (err < 0) {
-            goto out;
-        }
-        err = v9fs_co_lstat(pdu, &path, &stbuf);
-        if (err < 0) {
-            goto out;
+        if (not_same_qid(&pdu->s->root_qid, &qid) ||
+            strcmp("..", wnames[name_idx].data)) {
+            err = v9fs_co_name_to_path(pdu, &dpath, wnames[name_idx].data,
+                                       &path);
+            if (err < 0) {
+                goto out;
+            }
+
+            err = v9fs_co_lstat(pdu, &path, &stbuf);
+            if (err < 0) {
+                goto out;
+            }
+            stat_to_qid(&stbuf, &qid);
+            v9fs_path_copy(&dpath, &path);
         }
-        stat_to_qid(&stbuf, &qids[name_idx]);
-        v9fs_path_copy(&dpath, &path);
+        memcpy(&qids[name_idx], &qid, sizeof(qid));
     }
     if (fid == newfid) {
         BUG_ON(fidp->fid_type != P9_FID_NONE);
@@ -1361,7 +1396,7 @@ out_nofid:
     }
 }
 
-static int32_t get_iounit(V9fsPDU *pdu, V9fsPath *path)
+static int32_t coroutine_fn get_iounit(V9fsPDU *pdu, V9fsPath *path)
 {
     struct statfs stbuf;
     int32_t iounit = 0;
@@ -1381,7 +1416,7 @@ static int32_t get_iounit(V9fsPDU *pdu, V9fsPath *path)
     return iounit;
 }
 
-static void v9fs_open(void *opaque)
+static void coroutine_fn v9fs_open(void *opaque)
 {
     int flags;
     int32_t fid;
@@ -1471,7 +1506,7 @@ out_nofid:
     pdu_complete(pdu, err);
 }
 
-static void v9fs_lcreate(void *opaque)
+static void coroutine_fn v9fs_lcreate(void *opaque)
 {
     int32_t dfid, flags, mode;
     gid_t gid;
@@ -1568,7 +1603,7 @@ out_nofid:
     pdu_complete(pdu, err);
 }
 
-static void v9fs_clunk(void *opaque)
+static void coroutine_fn v9fs_clunk(void *opaque)
 {
     int err;
     int32_t fid;
@@ -1637,8 +1672,9 @@ static int v9fs_xattr_read(V9fsState *s, V9fsPDU *pdu, V9fsFidState *fidp,
     return offset;
 }
 
-static int v9fs_do_readdir_with_stat(V9fsPDU *pdu,
-                                     V9fsFidState *fidp, uint32_t max_count)
+static int coroutine_fn v9fs_do_readdir_with_stat(V9fsPDU *pdu,
+                                                  V9fsFidState *fidp,
+                                                  uint32_t max_count)
 {
     V9fsPath path;
     V9fsStat v9stat;
@@ -1728,7 +1764,7 @@ static void v9fs_init_qiov_from_pdu(QEMUIOVector *qiov, V9fsPDU *pdu,
     qemu_iovec_concat(qiov, &elem, skip, size);
 }
 
-static void v9fs_read(void *opaque)
+static void coroutine_fn v9fs_read(void *opaque)
 {
     int32_t fid;
     uint64_t off;
@@ -1790,14 +1826,15 @@ static void v9fs_read(void *opaque)
             if (len < 0) {
                 /* IO error return the error */
                 err = len;
-                goto out;
+                goto out_free_iovec;
             }
         } while (count < max_count && len > 0);
         err = pdu_marshal(pdu, offset, "d", count);
         if (err < 0) {
-            goto out;
+            goto out_free_iovec;
         }
         err += offset + count;
+out_free_iovec:
         qemu_iovec_destroy(&qiov);
         qemu_iovec_destroy(&qiov_full);
     } else if (fidp->fid_type == P9_FID_XATTR) {
@@ -1821,8 +1858,8 @@ static size_t v9fs_readdir_data_size(V9fsString *name)
     return 24 + v9fs_string_size(name);
 }
 
-static int v9fs_do_readdir(V9fsPDU *pdu,
-                           V9fsFidState *fidp, int32_t max_count)
+static int coroutine_fn v9fs_do_readdir(V9fsPDU *pdu, V9fsFidState *fidp,
+                                        int32_t max_count)
 {
     size_t size;
     V9fsQID qid;
@@ -1891,7 +1928,7 @@ static int v9fs_do_readdir(V9fsPDU *pdu,
     return count;
 }
 
-static void v9fs_readdir(void *opaque)
+static void coroutine_fn v9fs_readdir(void *opaque)
 {
     int32_t fid;
     V9fsFidState *fidp;
@@ -1987,7 +2024,7 @@ out:
     return err;
 }
 
-static void v9fs_write(void *opaque)
+static void coroutine_fn v9fs_write(void *opaque)
 {
     ssize_t err;
     int32_t fid;
@@ -2070,7 +2107,7 @@ out_nofid:
     pdu_complete(pdu, err);
 }
 
-static void v9fs_create(void *opaque)
+static void coroutine_fn v9fs_create(void *opaque)
 {
     int32_t fid;
     int err = 0;
@@ -2250,7 +2287,7 @@ out_nofid:
    v9fs_path_free(&path);
 }
 
-static void v9fs_symlink(void *opaque)
+static void coroutine_fn v9fs_symlink(void *opaque)
 {
     V9fsPDU *pdu = opaque;
     V9fsString name;
@@ -2339,7 +2376,7 @@ static void v9fs_flush(void *opaque)
     pdu_complete(pdu, 7);
 }
 
-static void v9fs_link(void *opaque)
+static void coroutine_fn v9fs_link(void *opaque)
 {
     V9fsPDU *pdu = opaque;
     int32_t dfid, oldfid;
@@ -2388,7 +2425,7 @@ out_nofid:
 }
 
 /* Only works with path name based fid */
-static void v9fs_remove(void *opaque)
+static void coroutine_fn v9fs_remove(void *opaque)
 {
     int32_t fid;
     int err = 0;
@@ -2432,7 +2469,7 @@ out_nofid:
     pdu_complete(pdu, err);
 }
 
-static void v9fs_unlinkat(void *opaque)
+static void coroutine_fn v9fs_unlinkat(void *opaque)
 {
     int err = 0;
     V9fsString name;
@@ -2495,8 +2532,9 @@ out_nofid:
 
 
 /* Only works with path name based fid */
-static int v9fs_complete_rename(V9fsPDU *pdu, V9fsFidState *fidp,
-                                int32_t newdirfid, V9fsString *name)
+static int coroutine_fn v9fs_complete_rename(V9fsPDU *pdu, V9fsFidState *fidp,
+                                             int32_t newdirfid,
+                                             V9fsString *name)
 {
     char *end;
     int err = 0;
@@ -2553,7 +2591,7 @@ out_nofid:
 }
 
 /* Only works with path name based fid */
-static void v9fs_rename(void *opaque)
+static void coroutine_fn v9fs_rename(void *opaque)
 {
     int32_t fid;
     ssize_t err = 0;
@@ -2604,9 +2642,10 @@ out_nofid:
     v9fs_string_free(&name);
 }
 
-static void v9fs_fix_fid_paths(V9fsPDU *pdu, V9fsPath *olddir,
-                               V9fsString *old_name, V9fsPath *newdir,
-                               V9fsString *new_name)
+static void coroutine_fn v9fs_fix_fid_paths(V9fsPDU *pdu, V9fsPath *olddir,
+                                            V9fsString *old_name,
+                                            V9fsPath *newdir,
+                                            V9fsString *new_name)
 {
     V9fsFidState *tfidp;
     V9fsPath oldpath, newpath;
@@ -2632,9 +2671,10 @@ static void v9fs_fix_fid_paths(V9fsPDU *pdu, V9fsPath *olddir,
     v9fs_path_free(&newpath);
 }
 
-static int v9fs_complete_renameat(V9fsPDU *pdu, int32_t olddirfid,
-                                  V9fsString *old_name, int32_t newdirfid,
-                                  V9fsString *new_name)
+static int coroutine_fn v9fs_complete_renameat(V9fsPDU *pdu, int32_t olddirfid,
+                                               V9fsString *old_name,
+                                               int32_t newdirfid,
+                                               V9fsString *new_name)
 {
     int err = 0;
     V9fsState *s = pdu->s;
@@ -2675,7 +2715,7 @@ out:
     return err;
 }
 
-static void v9fs_renameat(void *opaque)
+static void coroutine_fn v9fs_renameat(void *opaque)
 {
     ssize_t err = 0;
     size_t offset = 7;
@@ -2717,7 +2757,7 @@ out_err:
     v9fs_string_free(&new_name);
 }
 
-static void v9fs_wstat(void *opaque)
+static void coroutine_fn v9fs_wstat(void *opaque)
 {
     int32_t fid;
     int err = 0;
@@ -2856,7 +2896,7 @@ static int v9fs_fill_statfs(V9fsState *s, V9fsPDU *pdu, struct statfs *stbuf)
                        fsid_val, f_namelen);
 }
 
-static void v9fs_statfs(void *opaque)
+static void coroutine_fn v9fs_statfs(void *opaque)
 {
     int32_t fid;
     ssize_t retval = 0;
@@ -2890,7 +2930,7 @@ out_nofid:
     pdu_complete(pdu, retval);
 }
 
-static void v9fs_mknod(void *opaque)
+static void coroutine_fn v9fs_mknod(void *opaque)
 {
 
     int mode;
@@ -2956,7 +2996,7 @@ out_nofid:
  * do any thing in * qemu 9p server side lock code path.
  * So when a TLOCK request comes, always return success
  */
-static void v9fs_lock(void *opaque)
+static void coroutine_fn v9fs_lock(void *opaque)
 {
     int8_t status;
     V9fsFlock flock;
@@ -3009,7 +3049,7 @@ out_nofid:
  * When a TGETLOCK request comes, always return success because all lock
  * handling is done by client's VFS layer.
  */
-static void v9fs_getlock(void *opaque)
+static void coroutine_fn v9fs_getlock(void *opaque)
 {
     size_t offset = 7;
     struct stat stbuf;
@@ -3054,7 +3094,7 @@ out_nofid:
     v9fs_string_free(&glock.client_id);
 }
 
-static void v9fs_mkdir(void *opaque)
+static void coroutine_fn v9fs_mkdir(void *opaque)
 {
     V9fsPDU *pdu = opaque;
     size_t offset = 7;
@@ -3108,7 +3148,7 @@ out_nofid:
     v9fs_string_free(&name);
 }
 
-static void v9fs_xattrwalk(void *opaque)
+static void coroutine_fn v9fs_xattrwalk(void *opaque)
 {
     int64_t size;
     V9fsString name;
@@ -3138,7 +3178,7 @@ static void v9fs_xattrwalk(void *opaque)
         goto out;
     }
     v9fs_path_copy(&xattr_fidp->path, &file_fidp->path);
-    if (name.data == NULL) {
+    if (!v9fs_string_size(&name)) {
         /*
          * listxattr request. Get the size first
          */
@@ -3214,7 +3254,7 @@ out_nofid:
     v9fs_string_free(&name);
 }
 
-static void v9fs_xattrcreate(void *opaque)
+static void coroutine_fn v9fs_xattrcreate(void *opaque)
 {
     int flags;
     int32_t fid;
@@ -3254,7 +3294,7 @@ out_nofid:
     v9fs_string_free(&name);
 }
 
-static void v9fs_readlink(void *opaque)
+static void coroutine_fn v9fs_readlink(void *opaque)
 {
     V9fsPDU *pdu = opaque;
     size_t offset = 7;
@@ -3330,13 +3370,13 @@ static CoroutineEntry *pdu_co_handlers[] = {
     [P9_TREMOVE] = v9fs_remove,
 };
 
-static void v9fs_op_not_supp(void *opaque)
+static void coroutine_fn v9fs_op_not_supp(void *opaque)
 {
     V9fsPDU *pdu = opaque;
     pdu_complete(pdu, -EOPNOTSUPP);
 }
 
-static void v9fs_fs_ro(void *opaque)
+static void coroutine_fn v9fs_fs_ro(void *opaque)
 {
     V9fsPDU *pdu = opaque;
     pdu_complete(pdu, -EROFS);