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[fs/lustre-release.git] / lustre / liblustre / dir.c
1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2  * vim:expandtab:shiftwidth=8:tabstop=8:
3  *
4  * Lustre Light directory handling
5  *
6  *  Copyright (c) 2002-2004 Cluster File Systems, Inc.
7  *
8  *   This file is part of Lustre, http://www.lustre.org.
9  *
10  *   Lustre is free software; you can redistribute it and/or
11  *   modify it under the terms of version 2 of the GNU General Public
12  *   License as published by the Free Software Foundation.
13  *
14  *   Lustre is distributed in the hope that it will be useful,
15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  *   GNU General Public License for more details.
18  *
19  *   You should have received a copy of the GNU General Public License
20  *   along with Lustre; if not, write to the Free Software
21  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  */
23
24 #define DEBUG_SUBSYSTEM S_LLITE
25
26 #include <unistd.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <assert.h>
30 #include <time.h>
31 #include <sys/types.h>
32 #include <sys/stat.h>
33 #include <fcntl.h>
34 #include <sys/queue.h>
35
36 #ifdef HAVE_XTIO_H
37 #include <xtio.h>
38 #endif
39 #include <sysio.h>
40 #include <fs.h>
41 #include <mount.h>
42 #include <inode.h>
43 #ifdef HAVE_FILE_H
44 #include <file.h>
45 #endif
46
47 #undef LIST_HEAD
48
49 #ifdef HAVE_ASM_TYPES_H
50 #include <asm/types.h>
51 #elif defined(HAVE_SYS_TYPES_H)
52 #include <sys/types.h>
53 #endif
54
55 #ifdef HAVE_LINUX_UNISTD_H
56 #include <linux/unistd.h>
57 #elif defined(HAVE_UNISTD_H)
58 #include <unistd.h>
59 #endif
60
61 #include <dirent.h>
62
63 #include "llite_lib.h"
64
65 static int llu_dir_do_readpage(struct inode *inode, struct page *page)
66 {
67         struct llu_inode_info *lli = llu_i2info(inode);
68         struct intnl_stat *st = llu_i2stat(inode);
69         struct llu_sb_info *sbi = llu_i2sbi(inode);
70         struct ll_fid mdc_fid;
71         __u64 offset;
72         int rc = 0;
73         struct ptlrpc_request *request;
74         struct lustre_handle lockh;
75         struct mds_body *body;
76         struct lookup_intent it = { .it_op = IT_READDIR };
77         struct mdc_op_data data;
78         struct obd_device *obddev = class_exp2obd(sbi->ll_mdc_exp);
79         struct ldlm_res_id res_id =
80                 { .name = {st->st_ino, (__u64)lli->lli_st_generation} };
81         ldlm_policy_data_t policy = { .l_inodebits = { MDS_INODELOCK_UPDATE } };
82         ENTRY;
83
84         rc = ldlm_lock_match(obddev->obd_namespace, LDLM_FL_BLOCK_GRANTED,
85                              &res_id, LDLM_IBITS, &policy, LCK_CR, &lockh);
86         if (!rc) {
87                 llu_prepare_mdc_op_data(&data, inode, NULL, NULL, 0, 0);
88
89                 rc = mdc_enqueue(sbi->ll_mdc_exp, LDLM_IBITS, &it, LCK_CR,
90                                  &data, &lockh, NULL, 0,
91                                  ldlm_completion_ast, llu_mdc_blocking_ast,
92                                  inode, LDLM_FL_CANCEL_ON_BLOCK);
93                 request = (struct ptlrpc_request *)it.d.lustre.it_data;
94                 if (request)
95                         ptlrpc_req_finished(request);
96                 if (rc < 0) {
97                         CERROR("lock enqueue: err: %d\n", rc);
98                         RETURN(rc);
99                 }
100         }
101         ldlm_lock_dump_handle(D_OTHER, &lockh);
102
103         mdc_pack_fid(&mdc_fid, st->st_ino, lli->lli_st_generation, S_IFDIR);
104
105         offset = (__u64)page->index << CFS_PAGE_SHIFT;
106         rc = mdc_readpage(sbi->ll_mdc_exp, &mdc_fid,
107                           offset, page, &request);
108         if (!rc) {
109                 body = lustre_msg_buf(request->rq_repmsg, REPLY_REC_OFF,
110                                       sizeof(*body));
111                 LASSERT(body != NULL);         /* checked by mdc_readpage() */
112                 /* swabbed by mdc_readpage() */
113                 LASSERT_REPSWABBED(request, REPLY_REC_OFF);
114
115                 st->st_size = body->size;
116         } else {
117                 CERROR("read_dir_page(%ld) error %d\n", page->index, rc);
118         }
119         ptlrpc_req_finished(request);
120         EXIT;
121
122         ldlm_lock_decref(&lockh, LCK_CR);
123         return rc;
124 }
125
126 static struct page *llu_dir_read_page(struct inode *ino, unsigned long pgidx)
127 {
128         struct page *page;
129         int rc;
130         ENTRY;
131
132         page = alloc_page(0);
133         if (!page) {
134                 CERROR("alloc page failed\n");
135                 RETURN(ERR_PTR(-ENOMEM));
136         }
137         page->index = pgidx;
138
139         rc = llu_dir_do_readpage(ino, page);
140         if (rc) {
141                 free_page(page);
142                 RETURN(ERR_PTR(rc));
143         }
144
145         return page;
146 }
147
148 enum {
149         EXT2_FT_UNKNOWN,
150         EXT2_FT_REG_FILE,
151         EXT2_FT_DIR,
152         EXT2_FT_CHRDEV,
153         EXT2_FT_BLKDEV,
154         EXT2_FT_FIFO,
155         EXT2_FT_SOCK,
156         EXT2_FT_SYMLINK,
157         EXT2_FT_MAX
158 };
159
160 static unsigned char ext2_filetype_table[EXT2_FT_MAX] = {
161         [EXT2_FT_UNKNOWN]       DT_UNKNOWN,
162         [EXT2_FT_REG_FILE]      DT_REG,
163         [EXT2_FT_DIR]           DT_DIR,
164         [EXT2_FT_CHRDEV]        DT_CHR,
165         [EXT2_FT_BLKDEV]        DT_BLK,
166         [EXT2_FT_FIFO]          DT_FIFO,
167         [EXT2_FT_SOCK]          DT_SOCK,
168         [EXT2_FT_SYMLINK]       DT_LNK,
169 };
170
171 #define NAME_OFFSET(de) ((int) ((de)->d_name - (char *) (de)))
172 #define ROUND_UP64(x)   (((x)+sizeof(__u64)-1) & ~(sizeof(__u64)-1))
173
174 static int filldir(char *buf, int buflen,
175                    const char *name, int namelen, loff_t offset,
176                    ino_t ino, unsigned int d_type, int *filled)
177 {
178         struct dirent64 *dirent = (struct dirent64 *) (buf + *filled);
179         int reclen = ROUND_UP64(NAME_OFFSET(dirent) + namelen + 1);
180
181         /* check overflow */
182         if ((*filled + reclen) > buflen)
183                 return 1;
184
185         dirent->d_ino = ino;
186         dirent->d_off = offset;
187         dirent->d_reclen = reclen;
188 #ifndef _AIX
189         dirent->d_type = (unsigned short) d_type;
190 #endif
191         memcpy(dirent->d_name, name, namelen);
192         dirent->d_name[namelen] = 0;
193
194         *filled += reclen;
195
196         return 0;
197 }
198
199 ssize_t llu_iop_filldirentries(struct inode *ino, _SYSIO_OFF_T *basep, 
200                                char *buf, size_t nbytes)
201 {
202         struct llu_inode_info *lli = llu_i2info(ino);
203         struct intnl_stat *st = llu_i2stat(ino);
204         loff_t pos = *basep, offset;
205         int filled = 0;
206         unsigned long pgidx, maxpages;
207         ENTRY;
208
209         liblustre_wait_event(0);
210
211         if (st->st_size == 0) {
212                 CWARN("dir size is 0?\n");
213                 RETURN(0);
214         }
215
216         if (pos == -1)
217                 pos = lli->lli_dir_pos;
218
219         maxpages = (st->st_size + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT;
220         pgidx = pos >> CFS_PAGE_SHIFT;
221         offset = pos & ~CFS_PAGE_MASK;
222
223         for ( ; pgidx < maxpages ; pgidx++, offset = 0) {
224                 struct page *page;
225                 struct ext2_dirent *de;
226                 char *addr, *limit;
227
228                 page = llu_dir_read_page(ino, pgidx);
229                 if (IS_ERR(page))
230                         continue;
231
232                 /* size might have been updated by mdc_readpage */
233                 maxpages = (st->st_size + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT;
234
235                 /* fill in buffer */
236                 addr = page->addr;
237                 limit = addr + CFS_PAGE_SIZE - EXT2_DIR_REC_LEN(1);
238                 de = (struct ext2_dirent *) (addr + offset);
239
240                 for ( ; (char*) de <= limit; de = ext2_next_entry(de)) {
241                         if (de->inode) {
242                                 int over;
243                                 unsigned char d_type = DT_UNKNOWN;
244
245                                 if (de->file_type < EXT2_FT_MAX)
246                                         d_type = ext2_filetype_table[de->file_type];
247
248                                 offset = (char*) de - addr;
249                                 over =  filldir(buf, nbytes, de->name, de->name_len,
250                                                 (((__u64)pgidx << CFS_PAGE_SHIFT) | offset)
251                                                 + le16_to_cpu(de->rec_len),
252                                                 le32_to_cpu(de->inode), d_type, &filled);
253                                 if (over) {
254                                         free_page(page);
255                                         GOTO(done, 0);
256                                 }
257                         }
258                 }
259                 
260                 free_page(page);
261         }
262 done:
263         lli->lli_dir_pos = (__u64)pgidx << CFS_PAGE_SHIFT | offset;
264         *basep = lli->lli_dir_pos;
265         liblustre_wait_event(0);
266         RETURN(filled);
267 }