}
/* Ask the file system for its parent id and for its name (optional). */
ret = vnode_getattr(vp, &va, ctx);
+
if (fixhardlink) {
- if (vp->v_name || VATTR_IS_SUPPORTED(&va, va_name)) {
- if (ret == 0) {
- str = va.va_name;
- } else if (vp->v_name) {
- str = vp->v_name;
- ret = 0;
- } else {
- ret = ENOENT;
- goto bad_news;
- }
+ if ((ret == 0) && (VATTR_IS_SUPPORTED(&va, va_name))) {
+ str = va.va_name;
+ } else if (vp->v_name) {
+ str = vp->v_name;
+ ret = 0;
+ } else {
+ ret = ENOENT;
+ goto bad_news;
+ }
+ len = strlen(str);
- len = strlen(str);
-
- /* Check that there's enough space. */
- if ((end - buff) < (len + 1)) {
- ret = ENOSPC;
- } else {
- /* Copy the name backwards. */
- str += len;
-
- for (; len > 0; len--) {
- *--end = *--str;
- }
- /* Add a path separator. */
- *--end = '/';
+ /* Check that there's enough space. */
+ if ((end - buff) < (len + 1)) {
+ ret = ENOSPC;
+ } else {
+ /* Copy the name backwards. */
+ str += len;
+
+ for (; len > 0; len--) {
+ *--end = *--str;
}
+ /* Add a path separator. */
+ *--end = '/';
}
bad_news:
FREE_ZONE(va.va_name, MAXPATHLEN, M_NAMEI);
/*
* Returns: 0 Success
- * ENOENT No such file or directory
+ * ERECYCLE vnode was recycled from underneath us. Force lookup to be re-driven from namei.
+ * This errno value should not be seen by anyone outside of the kernel.
*/
int
-cache_lookup_path(struct nameidata *ndp, struct componentname *cnp, vnode_t dp, vfs_context_t ctx, int *trailing_slash, int *dp_authorized)
+cache_lookup_path(struct nameidata *ndp, struct componentname *cnp, vnode_t dp,
+ vfs_context_t ctx, int *trailing_slash, int *dp_authorized, vnode_t last_dp)
{
char *cp; /* pointer into pathname argument */
int vid;
kauth_cred_t ucred;
boolean_t ttl_enabled = FALSE;
struct timeval tv;
- mount_t mp;
+ mount_t mp;
unsigned int hash;
-#if CONFIG_MACF
- int error;
-#endif
+ int error = 0;
ucred = vfs_context_ucred(ctx);
*trailing_slash = 0;
error = mac_vnode_check_lookup(ctx, dp, cnp);
if (error) {
name_cache_unlock();
- return (error);
+ goto errorout;
}
}
#endif /* MAC */
dp = NULLVP;
} else {
need_dp:
- /*
+ /*
* return the last directory we looked at
- * with an io reference held
+ * with an io reference held. If it was the one passed
+ * in as a result of the last iteration of VNOP_LOOKUP,
+ * it should already hold an io ref. No need to increase ref.
*/
- if (dp == ndp->ni_usedvp) {
- /*
- * if this vnode matches the one passed in via USEDVP
- * than this context already holds an io_count... just
- * use vnode_get to get an extra ref for lookup to play
- * with... can't use the getwithvid variant here because
- * it will block behind a vnode_drain which would result
- * in a deadlock (since we already own an io_count that the
- * vnode_drain is waiting on)... vnode_get grabs the io_count
- * immediately w/o waiting... it always succeeds
- */
- vnode_get(dp);
- } else if ( (vnode_getwithvid(dp, vid)) ) {
- /*
- * failure indicates the vnode
- * changed identity or is being
- * TERMINATED... in either case
- * punt this lookup.
- *
- * don't necessarily return ENOENT, though, because
- * we really want to go back to disk and make sure it's
- * there or not if someone else is changing this
- * vnode.
- */
- return (ERESTART);
+ if (last_dp != dp){
+
+ if (dp == ndp->ni_usedvp) {
+ /*
+ * if this vnode matches the one passed in via USEDVP
+ * than this context already holds an io_count... just
+ * use vnode_get to get an extra ref for lookup to play
+ * with... can't use the getwithvid variant here because
+ * it will block behind a vnode_drain which would result
+ * in a deadlock (since we already own an io_count that the
+ * vnode_drain is waiting on)... vnode_get grabs the io_count
+ * immediately w/o waiting... it always succeeds
+ */
+ vnode_get(dp);
+ } else if ( (vnode_getwithvid(dp, vid)) ) {
+ /*
+ * failure indicates the vnode
+ * changed identity or is being
+ * TERMINATED... in either case
+ * punt this lookup.
+ *
+ * don't necessarily return ENOENT, though, because
+ * we really want to go back to disk and make sure it's
+ * there or not if someone else is changing this
+ * vnode.
+ */
+ error = ERECYCLE;
+ goto errorout;
+ }
}
}
if (vp != NULLVP) {
ndp->ni_dvp = dp;
ndp->ni_vp = vp;
- return (0);
+errorout:
+ /*
+ * If we came into cache_lookup_path after an iteration of the lookup loop that
+ * resulted in a call to VNOP_LOOKUP, then VNOP_LOOKUP returned a vnode with a io ref
+ * on it. It is now the job of cache_lookup_path to drop the ref on this vnode
+ * when it is no longer needed. If we get to this point, and last_dp is not NULL
+ * and it is ALSO not the dvp we want to return to caller of this function, it MUST be
+ * the case that we got to a subsequent path component and this previous vnode is
+ * no longer needed. We can then drop the io ref on it.
+ */
+ if ((last_dp != NULLVP) && (last_dp != ndp->ni_dvp)){
+ vnode_put(last_dp);
+ }
+
+ //initialized to 0, should be the same if no error cases occurred.
+ return error;
}
struct namecache *ncp;
kauth_cred_t tcred = NULL;
- if ((LIST_FIRST(&vp->v_nclinks) == NULL) && (LIST_FIRST(&vp->v_ncchildren) == NULL))
+ if ((LIST_FIRST(&vp->v_nclinks) == NULL) && (LIST_FIRST(&vp->v_ncchildren) == NULL) && (vp->v_cred == NOCRED))
return;
NAME_CACHE_LOCK();
projects / apple / xnu.git / blobdiff