1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 only,
10 * as published by the Free Software Foundation.
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License version 2 for more details (a copy is included
16 * in the LICENSE file that accompanied this code).
18 * You should have received a copy of the GNU General Public License
19 * version 2 along with this program; If not, see
20 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
29 * Copyright 2008 Sun Microsystems, Inc. All rights reserved
30 * Use is subject to license terms.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * lustre/liblustre/dir.c
38 * Lustre Light directory handling
41 #define DEBUG_SUBSYSTEM S_LLITE
48 #include <sys/types.h>
51 #include <sys/queue.h>
66 #ifdef HAVE_LINUX_UNISTD_H
67 #include <linux/unistd.h>
68 #elif defined(HAVE_UNISTD_H)
74 #include "llite_lib.h"
76 /* (new) readdir implementation overview can be found in lustre/llite/dir.c */
78 static int llu_dir_do_readpage(struct inode *inode, struct page *page)
80 struct llu_inode_info *lli = llu_i2info(inode);
81 struct intnl_stat *st = llu_i2stat(inode);
82 struct llu_sb_info *sbi = llu_i2sbi(inode);
83 struct ptlrpc_request *request;
84 struct lustre_handle lockh;
85 struct mdt_body *body;
86 struct lookup_intent it = { .it_op = IT_READDIR };
87 struct md_op_data op_data = {{ 0 }};
88 ldlm_policy_data_t policy = { .l_inodebits = { MDS_INODELOCK_UPDATE } };
93 rc = md_lock_match(sbi->ll_md_exp, LDLM_FL_BLOCK_GRANTED,
94 &lli->lli_fid, LDLM_IBITS, &policy, LCK_CR, &lockh);
96 struct ldlm_enqueue_info einfo = {LDLM_IBITS, LCK_CR,
97 llu_md_blocking_ast, ldlm_completion_ast, NULL, inode};
99 llu_prep_md_op_data(&op_data, inode, NULL, NULL, 0, 0,
102 rc = md_enqueue(sbi->ll_md_exp, &einfo, &it,
103 &op_data, &lockh, NULL, 0, NULL,
104 LDLM_FL_CANCEL_ON_BLOCK);
105 request = (struct ptlrpc_request *)it.d.lustre.it_data;
107 ptlrpc_req_finished(request);
109 CERROR("lock enqueue: err: %d\n", rc);
113 ldlm_lock_dump_handle(D_OTHER, &lockh);
115 offset = (__u64)hash_x_index(page->index);
116 rc = md_readpage(sbi->ll_md_exp, &lli->lli_fid, NULL,
117 offset, page, &request);
119 body = req_capsule_server_get(&request->rq_pill, &RMF_MDT_BODY);
120 LASSERT(body != NULL); /* checked by md_readpage() */
122 if (body->valid & OBD_MD_FLSIZE)
123 st->st_size = body->size;
125 CERROR("read_dir_page(%ld) error %d\n", page->index, rc);
127 ptlrpc_req_finished(request);
130 ldlm_lock_decref(&lockh, LCK_CR);
134 static cfs_page_t *llu_dir_read_page(struct inode *ino, __u32 hash,
135 int exact, struct ll_dir_chain *chain)
141 OBD_PAGE_ALLOC(page, 0);
143 RETURN(ERR_PTR(-ENOMEM));
144 page->index = hash_x_index(hash);
146 rc = llu_dir_do_readpage(ino, page);
155 void *(*memmover)(void *, const void *, size_t) = memmove;
157 #define NAME_OFFSET(de) ((int) ((de)->d_name - (char *) (de)))
158 #define ROUND_UP64(x) (((x)+sizeof(__u64)-1) & ~(sizeof(__u64)-1))
159 static int filldir(char *buf, int buflen,
160 const char *name, int namelen, loff_t offset,
161 ino_t ino, unsigned int d_type, int *filled)
163 cfs_dirent_t *dirent = (cfs_dirent_t *) (buf + *filled);
165 int reclen = ROUND_UP64(NAME_OFFSET(dirent) + namelen + 1);
168 * @buf is not guaranteed to be properly aligned. To work around,
169 * first fill stack-allocated @holder, then copy @holder into @buf by
174 if ((*filled + reclen) > buflen)
178 #ifdef _DIRENT_HAVE_D_OFF
179 holder.d_off = offset;
181 holder.d_reclen = reclen;
182 #ifdef _DIRENT_HAVE_D_TYPE
183 holder.d_type = (unsigned short) d_type;
185 /* gcc unrolls memcpy() of structs into field-wise assignments,
186 * assuming proper alignment. Humor it. */
187 (*memmover)(dirent, &holder, NAME_OFFSET(dirent));
188 memcpy(dirent->d_name, name, namelen);
189 dirent->d_name[namelen] = 0;
197 * TODO: much of the code here is similar/identical to llite ll_readdir().
198 * These code can be factored out and shared in a common module.
201 ssize_t llu_iop_filldirentries(struct inode *dir, _SYSIO_OFF_T *basep,
202 char *buf, size_t nbytes)
204 struct llu_inode_info *lli = llu_i2info(dir);
205 struct intnl_stat *st = llu_i2stat(dir);
207 struct ll_dir_chain chain;
215 liblustre_wait_event(0);
217 if (st->st_size == 0) {
218 CWARN("dir size is 0?\n");
222 if (pos == DIR_END_OFF)
231 ll_dir_chain_init(&chain);
233 page = llu_dir_read_page(dir, pos, 0, &chain);
234 while (rc == 0 && !done) {
235 struct lu_dirpage *dp;
236 struct lu_dirent *ent;
240 * If page is empty (end of directoryis reached),
243 __u64 hash = DIR_END_OFF;
247 for (ent = lu_dirent_start(dp); ent != NULL && !done;
248 ent = lu_dirent_next(ent)) {
254 hash = le64_to_cpu(ent->lde_hash);
255 namelen = le16_to_cpu(ent->lde_namelen);
259 * Skip until we find target hash
271 name = ent->lde_name;
272 fid_le_to_cpu(&fid, &fid);
273 ino = llu_fid_build_ino(llu_i2sbi(dir), &fid);
275 done = filldir(buf, nbytes, name, namelen,
276 (loff_t)hash, ino, DT_UNKNOWN,
279 next = le64_to_cpu(dp->ldp_hash_end);
283 if (pos == DIR_END_OFF)
285 * End of directory reached.
288 else if (1 /* chain is exhausted*/)
290 * Normal case: continue to the next
293 page = llu_dir_read_page(dir, pos, 1,
297 * go into overflow page.
303 GOTO(out, filled = -EINVAL);
307 CERROR("error reading dir "DFID" at %lu: rc %d\n",
308 PFID(&lli->lli_fid), (unsigned long)pos, rc);
311 lli->lli_dir_pos = (loff_t)(__s32)pos;
312 *basep = lli->lli_dir_pos;
314 ll_dir_chain_fini(&chain);
315 liblustre_wait_event(0);