Line data Source code
1 : /*
2 : Unix SMB/CIFS implementation.
3 : functions to calculate the free disk space
4 : Copyright (C) Andrew Tridgell 1998
5 :
6 : This program is free software; you can redistribute it and/or modify
7 : it under the terms of the GNU General Public License as published by
8 : the Free Software Foundation; either version 3 of the License, or
9 : (at your option) any later version.
10 :
11 : This program is distributed in the hope that it will be useful,
12 : but WITHOUT ANY WARRANTY; without even the implied warranty of
13 : MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 : GNU General Public License for more details.
15 :
16 : You should have received a copy of the GNU General Public License
17 : along with this program. If not, see <http://www.gnu.org/licenses/>.
18 : */
19 :
20 : #include "includes.h"
21 : #include "smbd/smbd.h"
22 : #include "smbd/globals.h"
23 : #include "lib/util_file.h"
24 : #include "lib/util/memcache.h"
25 :
26 : /****************************************************************************
27 : Normalise for DOS usage.
28 : ****************************************************************************/
29 :
30 1645 : static void disk_norm(uint64_t *bsize, uint64_t *dfree, uint64_t *dsize)
31 : {
32 : /* check if the disk is beyond the max disk size */
33 1645 : uint64_t maxdisksize = lp_max_disk_size();
34 1645 : if (maxdisksize) {
35 : /* convert to blocks - and don't overflow */
36 0 : maxdisksize = ((maxdisksize*1024)/(*bsize))*1024;
37 0 : if (*dsize > maxdisksize) {
38 0 : *dsize = maxdisksize;
39 : }
40 0 : if (*dfree > maxdisksize) {
41 0 : *dfree = maxdisksize - 1;
42 : }
43 : /* the -1 should stop applications getting div by 0
44 : errors */
45 : }
46 1645 : }
47 :
48 :
49 :
50 : /****************************************************************************
51 : Return number of 1K blocks available on a path and total number.
52 : ****************************************************************************/
53 :
54 1645 : static uint64_t sys_disk_free(connection_struct *conn,
55 : struct smb_filename *fname,
56 : uint64_t *bsize,
57 : uint64_t *dfree,
58 : uint64_t *dsize)
59 : {
60 0 : const struct loadparm_substitution *lp_sub =
61 1645 : loadparm_s3_global_substitution();
62 0 : uint64_t dfree_retval;
63 1645 : uint64_t dfree_q = 0;
64 1645 : uint64_t bsize_q = 0;
65 1645 : uint64_t dsize_q = 0;
66 0 : const char *dfree_command;
67 0 : static bool dfree_broken = false;
68 1645 : char *path = fname->base_name;
69 :
70 1645 : (*dfree) = (*dsize) = 0;
71 1645 : (*bsize) = 512;
72 :
73 : /*
74 : * If external disk calculation specified, use it.
75 : */
76 :
77 1645 : dfree_command = lp_dfree_command(talloc_tos(), lp_sub, SNUM(conn));
78 1645 : if (dfree_command && *dfree_command) {
79 0 : const char *p;
80 10 : char **lines = NULL;
81 10 : char **argl = NULL;
82 :
83 10 : argl = str_list_make_empty(talloc_tos());
84 10 : str_list_add_printf(&argl, "%s", dfree_command);
85 10 : str_list_add_printf(&argl, "%s", path);
86 10 : if (argl == NULL) {
87 0 : return (uint64_t)-1;
88 : }
89 :
90 10 : DBG_NOTICE("Running command '%s %s'\n",
91 : dfree_command,
92 : path);
93 :
94 10 : lines = file_lines_ploadv(talloc_tos(), argl, NULL);
95 :
96 10 : TALLOC_FREE(argl);
97 :
98 10 : if (lines != NULL) {
99 10 : char *line = lines[0];
100 :
101 10 : DEBUG (3, ("Read input from dfree, \"%s\"\n", line));
102 :
103 10 : *dsize = STR_TO_SMB_BIG_UINT(line, &p);
104 20 : while (p && *p && isspace(*p))
105 10 : p++;
106 10 : if (p && *p)
107 10 : *dfree = STR_TO_SMB_BIG_UINT(p, &p);
108 20 : while (p && *p && isspace(*p))
109 10 : p++;
110 10 : if (p && *p)
111 10 : *bsize = STR_TO_SMB_BIG_UINT(p, NULL);
112 : else
113 0 : *bsize = 1024;
114 10 : TALLOC_FREE(lines);
115 10 : DEBUG (3, ("Parsed output of dfree, dsize=%u, dfree=%u, bsize=%u\n",
116 : (unsigned int)*dsize, (unsigned int)*dfree, (unsigned int)*bsize));
117 :
118 10 : if (!*dsize)
119 0 : *dsize = 2048;
120 10 : if (!*dfree)
121 0 : *dfree = 1024;
122 :
123 10 : goto dfree_done;
124 : }
125 0 : DBG_ERR("file_lines_load() failed for "
126 : "command '%s %s'. Error was : %s\n",
127 : dfree_command, path, strerror(errno));
128 : }
129 :
130 1635 : if (SMB_VFS_DISK_FREE(conn, fname, bsize, dfree, dsize) ==
131 : (uint64_t)-1) {
132 0 : DBG_ERR("VFS disk_free failed. Error was : %s\n",
133 : strerror(errno));
134 0 : return (uint64_t)-1;
135 : }
136 :
137 1635 : if (disk_quotas(conn, fname, &bsize_q, &dfree_q, &dsize_q)) {
138 36 : uint64_t min_bsize = MIN(*bsize, bsize_q);
139 :
140 36 : (*dfree) = (*dfree) * (*bsize) / min_bsize;
141 36 : (*dsize) = (*dsize) * (*bsize) / min_bsize;
142 36 : dfree_q = dfree_q * bsize_q / min_bsize;
143 36 : dsize_q = dsize_q * bsize_q / min_bsize;
144 :
145 36 : (*bsize) = min_bsize;
146 36 : (*dfree) = MIN(*dfree,dfree_q);
147 36 : (*dsize) = MIN(*dsize,dsize_q);
148 : }
149 :
150 : /* FIXME : Any reason for this assumption ? */
151 1635 : if (*bsize < 256) {
152 0 : DEBUG(5,("disk_free:Warning: bsize == %d < 256 . Changing to assumed correct bsize = 512\n",(int)*bsize));
153 0 : *bsize = 512;
154 : }
155 :
156 1635 : if ((*dsize)<1) {
157 0 : if (!dfree_broken) {
158 0 : DEBUG(0,("WARNING: dfree is broken on this system\n"));
159 0 : dfree_broken=true;
160 : }
161 0 : *dsize = 20*1024*1024/(*bsize);
162 0 : *dfree = MAX(1,*dfree);
163 : }
164 :
165 1635 : dfree_done:
166 1645 : disk_norm(bsize, dfree, dsize);
167 :
168 1645 : if ((*bsize) < 1024) {
169 1595 : dfree_retval = (*dfree)/(1024/(*bsize));
170 : } else {
171 50 : dfree_retval = ((*bsize)/1024)*(*dfree);
172 : }
173 :
174 1645 : return(dfree_retval);
175 : }
176 :
177 : /****************************************************************************
178 : Potentially returned cached dfree info.
179 :
180 : Depending on the file system layout and file system features, the free space
181 : information can be different for different sub directories underneath a SMB
182 : share. Store the cache information in memcache using the query path as the
183 : key to accommodate this.
184 : ****************************************************************************/
185 :
186 : struct dfree_cached_info {
187 : time_t last_dfree_time;
188 : uint64_t dfree_ret;
189 : uint64_t bsize;
190 : uint64_t dfree;
191 : uint64_t dsize;
192 : };
193 :
194 1645 : uint64_t get_dfree_info(connection_struct *conn, struct smb_filename *fname,
195 : uint64_t *bsize, uint64_t *dfree, uint64_t *dsize)
196 : {
197 1645 : int dfree_cache_time = lp_dfree_cache_time(SNUM(conn));
198 1645 : struct dfree_cached_info *dfc = NULL;
199 1645 : struct dfree_cached_info dfc_new = { 0 };
200 0 : uint64_t dfree_ret;
201 0 : char tmpbuf[PATH_MAX];
202 1645 : char *full_path = NULL;
203 1645 : char *to_free = NULL;
204 1645 : char *key_path = NULL;
205 0 : size_t len;
206 0 : DATA_BLOB key, value;
207 0 : bool found;
208 :
209 1645 : if (!dfree_cache_time) {
210 1641 : return sys_disk_free(conn, fname, bsize, dfree, dsize);
211 : }
212 :
213 8 : len = full_path_tos(conn->connectpath,
214 4 : fname->base_name,
215 : tmpbuf,
216 : sizeof(tmpbuf),
217 : &full_path,
218 : &to_free);
219 4 : if (len == -1) {
220 0 : errno = ENOMEM;
221 0 : return -1;
222 : }
223 :
224 4 : if (VALID_STAT(fname->st) && S_ISREG(fname->st.st_ex_mode)) {
225 : /*
226 : * In case of a file use the parent directory to reduce number
227 : * of cache entries.
228 : */
229 0 : bool ok;
230 :
231 0 : ok = parent_dirname(talloc_tos(),
232 : full_path,
233 : &key_path,
234 : NULL);
235 0 : TALLOC_FREE(to_free); /* We're done with full_path */
236 :
237 0 : if (!ok) {
238 0 : errno = ENOMEM;
239 0 : return -1;
240 : }
241 :
242 : /*
243 : * key_path is always a talloced object.
244 : */
245 0 : to_free = key_path;
246 : } else {
247 : /*
248 : * key_path might not be a talloced object; rely on
249 : * to_free set from full_path_tos.
250 : */
251 4 : key_path = full_path;
252 : }
253 :
254 4 : key = data_blob_const(key_path, strlen(key_path));
255 4 : found = memcache_lookup(smbd_memcache(),
256 : DFREE_CACHE,
257 : key,
258 : &value);
259 4 : dfc = found ? (struct dfree_cached_info *)value.data : NULL;
260 :
261 4 : if (dfc && (conn->lastused - dfc->last_dfree_time < dfree_cache_time)) {
262 0 : DBG_DEBUG("Returning dfree cache entry for %s\n", key_path);
263 0 : *bsize = dfc->bsize;
264 0 : *dfree = dfc->dfree;
265 0 : *dsize = dfc->dsize;
266 0 : dfree_ret = dfc->dfree_ret;
267 0 : goto out;
268 : }
269 :
270 4 : dfree_ret = sys_disk_free(conn, fname, bsize, dfree, dsize);
271 :
272 4 : if (dfree_ret == (uint64_t)-1) {
273 : /* Don't cache bad data. */
274 0 : goto out;
275 : }
276 :
277 4 : DBG_DEBUG("Creating dfree cache entry for %s\n", key_path);
278 4 : dfc_new.bsize = *bsize;
279 4 : dfc_new.dfree = *dfree;
280 4 : dfc_new.dsize = *dsize;
281 4 : dfc_new.dfree_ret = dfree_ret;
282 4 : dfc_new.last_dfree_time = conn->lastused;
283 4 : memcache_add(smbd_memcache(),
284 : DFREE_CACHE,
285 : key,
286 : data_blob_const(&dfc_new, sizeof(dfc_new)));
287 :
288 4 : out:
289 4 : TALLOC_FREE(to_free);
290 4 : return dfree_ret;
291 : }
292 :
293 1208 : void flush_dfree_cache(void)
294 : {
295 1208 : memcache_flush(smbd_memcache(), DFREE_CACHE);
296 1208 : }
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