RETURN(0);
}
-/** The maximum depth that fid2path() will search.
- * This is limited only because we want to store the fids for
- * historical path lookup purposes.
- */
-#define MAX_PATH_DEPTH 100
-
-/** mdt_path() lookup structure. */
-struct path_lookup_info {
- __u64 pli_recno; /**< history point */
- __u64 pli_currec; /**< current record */
- struct lu_fid pli_fid;
- struct lu_fid pli_fids[MAX_PATH_DEPTH]; /**< path, in fids */
- struct mdt_object *pli_mdt_obj;
- char *pli_path; /**< full path */
- int pli_pathlen;
- int pli_linkno; /**< which hardlink to follow */
- int pli_fidcount; /**< number of \a pli_fids */
-};
-
int mdt_links_read(struct mdt_thread_info *info, struct mdt_object *mdt_obj,
struct linkea_data *ldata)
{
return linkea_init(ldata);
}
+/**
+ * Given an MDT object, try to look up the full path to the object.
+ * Part of the MDT layer implementation of lfs fid2path.
+ *
+ * \param[in] info Per-thread common data shared by MDT level handlers.
+ * \param[in] obj Object to do path lookup of
+ * \param[in,out] fp User-provided struct to store path information
+ *
+ * \retval 0 Lookup successful, path information stored in fp
+ * \retval -EAGAIN Lookup failed, usually because object is being moved
+ * \retval negative errno if there was a problem
+ */
static int mdt_path_current(struct mdt_thread_info *info,
- struct path_lookup_info *pli)
+ struct mdt_object *obj,
+ struct getinfo_fid2path *fp)
{
struct mdt_device *mdt = info->mti_mdt;
struct mdt_object *mdt_obj;
int reclen;
struct linkea_data ldata = { 0 };
int rc = 0;
+ bool first = true;
ENTRY;
/* temp buffer for path element, the buffer will be finally freed
RETURN(-ENOMEM);
ldata.ld_buf = buf;
- ptr = pli->pli_path + pli->pli_pathlen - 1;
+ ptr = fp->gf_path + fp->gf_pathlen - 1;
*ptr = 0;
--ptr;
- pli->pli_fidcount = 0;
- pli->pli_fids[0] = *(struct lu_fid *)mdt_object_fid(pli->pli_mdt_obj);
- *tmpfid = pli->pli_fids[0];
+ *tmpfid = fp->gf_fid = *mdt_object_fid(obj);
+
/* root FID only exists on MDT0, and fid2path should also ends at MDT0,
* so checking root_fid can only happen on MDT0. */
- while (!lu_fid_eq(&mdt->mdt_md_root_fid,
- &pli->pli_fids[pli->pli_fidcount])) {
+ while (!lu_fid_eq(&mdt->mdt_md_root_fid, &fp->gf_fid)) {
struct lu_buf lmv_buf;
mdt_obj = mdt_object_find(info->mti_env, mdt, tmpfid);
linkea_entry_unpack(lee, &reclen, tmpname, tmpfid);
/* If set, use link #linkno for path lookup, otherwise use
link #0. Only do this for the final path element. */
- if (pli->pli_fidcount == 0 &&
- pli->pli_linkno < leh->leh_reccount) {
+ if (first && fp->gf_linkno < leh->leh_reccount) {
int count;
- for (count = 0; count < pli->pli_linkno; count++) {
+ for (count = 0; count < fp->gf_linkno; count++) {
lee = (struct link_ea_entry *)
((char *)lee + reclen);
linkea_entry_unpack(lee, &reclen, tmpname,
tmpfid);
}
- if (pli->pli_linkno < leh->leh_reccount - 1)
+ if (fp->gf_linkno < leh->leh_reccount - 1)
/* indicate to user there are more links */
- pli->pli_linkno++;
+ fp->gf_linkno++;
}
lmv_buf.lb_buf = info->mti_xattr_buf;
/* For slave stripes, get its master */
if (le32_to_cpu(lmm->lmv_magic) == LMV_MAGIC_STRIPE) {
- pli->pli_fids[pli->pli_fidcount] = *tmpfid;
+ fp->gf_fid = *tmpfid;
continue;
}
} else if (rc < 0 && rc != -ENODATA) {
/* Pack the name in the end of the buffer */
ptr -= tmpname->ln_namelen;
- if (ptr - 1 <= pli->pli_path)
+ if (ptr - 1 <= fp->gf_path)
GOTO(out, rc = -EOVERFLOW);
strncpy(ptr, tmpname->ln_name, tmpname->ln_namelen);
*(--ptr) = '/';
- /* Store the parent fid for historic lookup */
- if (++pli->pli_fidcount >= MAX_PATH_DEPTH)
- GOTO(out, rc = -EOVERFLOW);
- pli->pli_fids[pli->pli_fidcount] = *tmpfid;
+ /* keep the last resolved fid to the client, so the
+ * client will build the left path on another MDT for
+ * remote object */
+ fp->gf_fid = *tmpfid;
+
+ first = false;
}
remote_out:
ptr++; /* skip leading / */
- memmove(pli->pli_path, ptr, pli->pli_path + pli->pli_pathlen - ptr);
+ memmove(fp->gf_path, ptr, fp->gf_path + fp->gf_pathlen - ptr);
- EXIT;
out:
- return rc;
+ RETURN(rc);
}
-/* Returns the full path to this fid, as of changelog record recno. */
+/**
+ * Given an MDT object, use mdt_path_current to get the path.
+ * Essentially a wrapper to retry mdt_path_current a set number of times
+ * if -EAGAIN is returned (usually because an object is being moved).
+ *
+ * Part of the MDT layer implementation of lfs fid2path.
+ *
+ * \param[in] info Per-thread common data shared by mdt level handlers.
+ * \param[in] obj Object to do path lookup of
+ * \param[in,out] fp User-provided struct for arguments and to store path
+ * information
+ *
+ * \retval 0 Lookup successful, path information stored in fp
+ * \retval negative errno if there was a problem
+ */
static int mdt_path(struct mdt_thread_info *info, struct mdt_object *obj,
- char *path, int pathlen, __u64 *recno, int *linkno,
- struct lu_fid *fid)
+ struct getinfo_fid2path *fp)
{
struct mdt_device *mdt = info->mti_mdt;
- struct path_lookup_info *pli;
int tries = 3;
int rc = -EAGAIN;
ENTRY;
- if (pathlen < 3)
+ if (fp->gf_pathlen < 3)
RETURN(-EOVERFLOW);
if (lu_fid_eq(&mdt->mdt_md_root_fid, mdt_object_fid(obj))) {
- path[0] = '\0';
+ fp->gf_path[0] = '\0';
RETURN(0);
}
- OBD_ALLOC_PTR(pli);
- if (pli == NULL)
- RETURN(-ENOMEM);
-
- pli->pli_mdt_obj = obj;
- pli->pli_recno = *recno;
- pli->pli_path = path;
- pli->pli_pathlen = pathlen;
- pli->pli_linkno = *linkno;
-
/* Retry multiple times in case file is being moved */
while (tries-- && rc == -EAGAIN)
- rc = mdt_path_current(info, pli);
-
- /* return the last resolved fids to the client, so the client will
- * build the left path on another MDT for remote object */
- *fid = pli->pli_fids[pli->pli_fidcount];
-
- *recno = pli->pli_currec;
- /* Return next link index to caller */
- *linkno = pli->pli_linkno;
-
- OBD_FREE_PTR(pli);
+ rc = mdt_path_current(info, obj, fp);
RETURN(rc);
}
+/**
+ * Get the full path of the provided FID, as of changelog record recno.
+ *
+ * This checks sanity and looks up object for user provided FID
+ * before calling the actual path lookup code.
+ *
+ * Part of the MDT layer implementation of lfs fid2path.
+ *
+ * \param[in] info Per-thread common data shared by mdt level handlers.
+ * \param[in,out] fp User-provided struct for arguments and to store path
+ * information
+ *
+ * \retval 0 Lookup successful, path information and recno stored in fp
+ * \retval -ENOENT, object does not exist
+ * \retval negative errno if there was a problem
+ */
static int mdt_fid2path(struct mdt_thread_info *info,
struct getinfo_fid2path *fp)
{
RETURN(rc);
}
- rc = mdt_path(info, obj, fp->gf_path, fp->gf_pathlen, &fp->gf_recno,
- &fp->gf_linkno, &fp->gf_fid);
+ rc = mdt_path(info, obj, fp);
CDEBUG(D_INFO, "fid "DFID", path %s recno "LPX64" linkno %u\n",
PFID(&fp->gf_fid), fp->gf_path, fp->gf_recno, fp->gf_linkno);
git://git.whamcloud.com / fs / lustre-release.git / commitdiff