4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.gnu.org/licenses/gpl-2.0.html
23 * Copyright (c) 2013, 2014, Intel Corporation.
24 * Use is subject to license terms.
26 * Author: Di Wang <di.wang@intel.com>
29 #include <uapi/linux/lustre/lustre_idl.h>
31 #include <lustre_linkea.h>
33 int linkea_data_new(struct linkea_data *ldata, struct lu_buf *buf)
35 ldata->ld_buf = lu_buf_check_and_alloc(buf, PAGE_SIZE);
36 if (!ldata->ld_buf->lb_buf)
38 ldata->ld_leh = ldata->ld_buf->lb_buf;
39 ldata->ld_leh->leh_magic = LINK_EA_MAGIC;
40 ldata->ld_leh->leh_len = sizeof(struct link_ea_header);
41 ldata->ld_leh->leh_reccount = 0;
42 ldata->ld_leh->leh_overflow_time = 0;
43 ldata->ld_leh->leh_padding = 0;
46 EXPORT_SYMBOL(linkea_data_new);
48 int linkea_init(struct linkea_data *ldata)
50 struct link_ea_header *leh;
52 LASSERT(ldata->ld_buf);
53 leh = ldata->ld_buf->lb_buf;
54 if (leh->leh_magic == __swab32(LINK_EA_MAGIC)) {
55 leh->leh_magic = LINK_EA_MAGIC;
56 leh->leh_reccount = __swab32(leh->leh_reccount);
57 leh->leh_len = __swab64(leh->leh_len);
58 leh->leh_overflow_time = __swab32(leh->leh_overflow_time);
59 leh->leh_padding = __swab32(leh->leh_padding);
60 /* individual entries are swabbed by linkea_entry_unpack() */
63 if (leh->leh_magic != LINK_EA_MAGIC)
66 if (leh->leh_reccount == 0 && leh->leh_overflow_time == 0)
72 EXPORT_SYMBOL(linkea_init);
74 int linkea_init_with_rec(struct linkea_data *ldata)
78 rc = linkea_init(ldata);
79 if (!rc && ldata->ld_leh->leh_reccount == 0)
84 EXPORT_SYMBOL(linkea_init_with_rec);
87 * Pack a link_ea_entry.
88 * All elements are stored as chars to avoid alignment issues.
89 * Numbers are always big-endian
90 * \retval record length
92 int linkea_entry_pack(struct link_ea_entry *lee, const struct lu_name *lname,
93 const struct lu_fid *pfid)
99 if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_LINKEA_CRASH))
101 fid_cpu_to_be(&tmpfid, &tmpfid);
102 memcpy(&lee->lee_parent_fid, &tmpfid, sizeof(tmpfid));
103 memcpy(lee->lee_name, lname->ln_name, lname->ln_namelen);
104 reclen = sizeof(struct link_ea_entry) + lname->ln_namelen;
106 lee->lee_reclen[0] = (reclen >> 8) & 0xff;
107 lee->lee_reclen[1] = reclen & 0xff;
110 EXPORT_SYMBOL(linkea_entry_pack);
112 void linkea_entry_unpack(const struct link_ea_entry *lee, int *reclen,
113 struct lu_name *lname, struct lu_fid *pfid)
117 *reclen = (lee->lee_reclen[0] << 8) | lee->lee_reclen[1];
118 memcpy(pfid, &lee->lee_parent_fid, sizeof(*pfid));
119 fid_be_to_cpu(pfid, pfid);
121 lname->ln_name = lee->lee_name;
122 lname->ln_namelen = *reclen - sizeof(struct link_ea_entry);
125 EXPORT_SYMBOL(linkea_entry_unpack);
128 * Add a record to the end of link ea buf
130 int linkea_add_buf(struct linkea_data *ldata, const struct lu_name *lname,
131 const struct lu_fid *pfid)
133 struct link_ea_header *leh = ldata->ld_leh;
141 reclen = lname->ln_namelen + sizeof(struct link_ea_entry);
142 if (unlikely(leh->leh_len + reclen > MAX_LINKEA_SIZE)) {
144 * Use 32-bits to save the overflow time, although it will
145 * shrink the ktime_get_real_seconds() returned 64-bits value
146 * to 32-bits value, it is still quite large and can be used
147 * for about 140 years. That is enough.
149 leh->leh_overflow_time = ktime_get_real_seconds();
150 if (unlikely(leh->leh_overflow_time == 0))
151 leh->leh_overflow_time++;
153 CDEBUG(D_INODE, "No enough space to hold linkea entry '" DFID ": %.*s' at %u\n",
154 PFID(pfid), lname->ln_namelen,
155 lname->ln_name, leh->leh_overflow_time);
159 if (leh->leh_len + reclen > ldata->ld_buf->lb_len) {
160 if (lu_buf_check_and_grow(ldata->ld_buf,
161 leh->leh_len + reclen) < 0)
164 leh = ldata->ld_leh = ldata->ld_buf->lb_buf;
167 ldata->ld_lee = ldata->ld_buf->lb_buf + leh->leh_len;
168 ldata->ld_reclen = linkea_entry_pack(ldata->ld_lee, lname, pfid);
169 leh->leh_len += ldata->ld_reclen;
171 CDEBUG(D_INODE, "New link_ea name '" DFID ":%.*s' is added\n",
172 PFID(pfid), lname->ln_namelen, lname->ln_name);
175 EXPORT_SYMBOL(linkea_add_buf);
177 /** Del the current record from the link ea buf */
178 void linkea_del_buf(struct linkea_data *ldata, const struct lu_name *lname)
180 LASSERT(ldata->ld_leh && ldata->ld_lee);
181 LASSERT(ldata->ld_leh->leh_reccount > 0);
183 ldata->ld_leh->leh_reccount--;
184 ldata->ld_leh->leh_len -= ldata->ld_reclen;
185 memmove(ldata->ld_lee, (char *)ldata->ld_lee + ldata->ld_reclen,
186 (char *)ldata->ld_leh + ldata->ld_leh->leh_len -
187 (char *)ldata->ld_lee);
188 CDEBUG(D_INODE, "Old link_ea name '%.*s' is removed\n",
189 lname->ln_namelen, lname->ln_name);
191 if ((char *)ldata->ld_lee >= ((char *)ldata->ld_leh +
192 ldata->ld_leh->leh_len))
193 ldata->ld_lee = NULL;
195 EXPORT_SYMBOL(linkea_del_buf);
198 * Check if such a link exists in linkEA.
200 * \param ldata link data the search to be done on
201 * \param lname name in the parent's directory entry pointing to this object
202 * \param pfid parent fid the link to be found for
205 * \retval -ENOENT link does not exist
206 * \retval -ve on error
208 int linkea_links_find(struct linkea_data *ldata, const struct lu_name *lname,
209 const struct lu_fid *pfid)
211 struct lu_name tmpname;
212 struct lu_fid tmpfid;
215 LASSERT(ldata->ld_leh);
217 /* link #0, if leh_reccount == 0 we skip the loop and return -ENOENT */
218 if (likely(ldata->ld_leh->leh_reccount > 0))
219 ldata->ld_lee = (struct link_ea_entry *)(ldata->ld_leh + 1);
221 for (count = 0; count < ldata->ld_leh->leh_reccount; count++) {
222 linkea_entry_unpack(ldata->ld_lee, &ldata->ld_reclen,
224 if (tmpname.ln_namelen == lname->ln_namelen &&
225 lu_fid_eq(&tmpfid, pfid) &&
226 (strncmp(tmpname.ln_name, lname->ln_name,
227 tmpname.ln_namelen) == 0))
229 ldata->ld_lee = (struct link_ea_entry *)((char *)ldata->ld_lee +
233 if (count == ldata->ld_leh->leh_reccount) {
234 CDEBUG(D_INODE, "Old link_ea name '%.*s' not found\n",
235 lname->ln_namelen, lname->ln_name);
236 ldata->ld_lee = NULL;
237 ldata->ld_reclen = 0;
242 EXPORT_SYMBOL(linkea_links_find);