Bug Summary

File:msdosfs/msdosfs_denode.c
Warning:line 327, column 5
Value stored to 'error' is never read

Annotated Source Code

Press '?' to see keyboard shortcuts

clang -cc1 -cc1 -triple amd64-unknown-openbsd7.4 -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name msdosfs_denode.c -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model static -mframe-pointer=all -relaxed-aliasing -ffp-contract=on -fno-rounding-math -mconstructor-aliases -ffreestanding -mcmodel=kernel -target-cpu x86-64 -target-feature +retpoline-indirect-calls -target-feature +retpoline-indirect-branches -target-feature -sse2 -target-feature -sse -target-feature -3dnow -target-feature -mmx -target-feature +save-args -target-feature +retpoline-external-thunk -disable-red-zone -no-implicit-float -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/sys/arch/amd64/compile/GENERIC.MP/obj -nostdsysteminc -nobuiltininc -resource-dir /usr/local/llvm16/lib/clang/16 -I /usr/src/sys -I /usr/src/sys/arch/amd64/compile/GENERIC.MP/obj -I /usr/src/sys/arch -I /usr/src/sys/dev/pci/drm/include -I /usr/src/sys/dev/pci/drm/include/uapi -I /usr/src/sys/dev/pci/drm/amd/include/asic_reg -I /usr/src/sys/dev/pci/drm/amd/include -I /usr/src/sys/dev/pci/drm/amd/amdgpu -I /usr/src/sys/dev/pci/drm/amd/display -I /usr/src/sys/dev/pci/drm/amd/display/include -I /usr/src/sys/dev/pci/drm/amd/display/dc -I /usr/src/sys/dev/pci/drm/amd/display/amdgpu_dm -I /usr/src/sys/dev/pci/drm/amd/pm/inc -I /usr/src/sys/dev/pci/drm/amd/pm/legacy-dpm -I /usr/src/sys/dev/pci/drm/amd/pm/swsmu -I /usr/src/sys/dev/pci/drm/amd/pm/swsmu/inc -I /usr/src/sys/dev/pci/drm/amd/pm/swsmu/smu11 -I /usr/src/sys/dev/pci/drm/amd/pm/swsmu/smu12 -I /usr/src/sys/dev/pci/drm/amd/pm/swsmu/smu13 -I /usr/src/sys/dev/pci/drm/amd/pm/powerplay/inc -I /usr/src/sys/dev/pci/drm/amd/pm/powerplay/hwmgr -I /usr/src/sys/dev/pci/drm/amd/pm/powerplay/smumgr -I /usr/src/sys/dev/pci/drm/amd/pm/swsmu/inc -I /usr/src/sys/dev/pci/drm/amd/pm/swsmu/inc/pmfw_if -I /usr/src/sys/dev/pci/drm/amd/display/dc/inc -I /usr/src/sys/dev/pci/drm/amd/display/dc/inc/hw -I /usr/src/sys/dev/pci/drm/amd/display/dc/clk_mgr -I /usr/src/sys/dev/pci/drm/amd/display/modules/inc -I /usr/src/sys/dev/pci/drm/amd/display/modules/hdcp -I /usr/src/sys/dev/pci/drm/amd/display/dmub/inc -I /usr/src/sys/dev/pci/drm/i915 -D DDB -D DIAGNOSTIC -D KTRACE -D ACCOUNTING -D KMEMSTATS -D PTRACE -D POOL_DEBUG -D CRYPTO -D SYSVMSG -D SYSVSEM -D SYSVSHM -D UVM_SWAP_ENCRYPT -D FFS -D FFS2 -D FFS_SOFTUPDATES -D UFS_DIRHASH -D QUOTA -D EXT2FS -D MFS -D NFSCLIENT -D NFSSERVER -D CD9660 -D UDF -D MSDOSFS -D FIFO -D FUSE -D SOCKET_SPLICE -D TCP_ECN -D TCP_SIGNATURE -D INET6 -D IPSEC -D PPP_BSDCOMP -D PPP_DEFLATE -D PIPEX -D MROUTING -D MPLS -D BOOT_CONFIG -D USER_PCICONF -D APERTURE -D MTRR -D NTFS -D SUSPEND -D HIBERNATE -D PCIVERBOSE -D USBVERBOSE -D WSDISPLAY_COMPAT_USL -D WSDISPLAY_COMPAT_RAWKBD -D WSDISPLAY_DEFAULTSCREENS=6 -D X86EMU -D ONEWIREVERBOSE -D MULTIPROCESSOR -D MAXUSERS=80 -D _KERNEL -O2 -Wno-pointer-sign -Wno-address-of-packed-member -Wno-constant-conversion -Wno-unused-but-set-variable -Wno-gnu-folding-constant -fdebug-compilation-dir=/usr/src/sys/arch/amd64/compile/GENERIC.MP/obj -ferror-limit 19 -fwrapv -D_RET_PROTECTOR -ret-protector -fcf-protection=branch -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -o /home/ben/Projects/scan/2024-01-11-110808-61670-1 -x c /usr/src/sys/msdosfs/msdosfs_denode.c
1/* $OpenBSD: msdosfs_denode.c,v 1.68 2023/03/08 04:43:08 guenther Exp $ */
2/* $NetBSD: msdosfs_denode.c,v 1.23 1997/10/17 11:23:58 ws Exp $ */
3
4/*-
5 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
6 * Copyright (C) 1994, 1995, 1997 TooLs GmbH.
7 * All rights reserved.
8 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by TooLs GmbH.
21 * 4. The name of TooLs GmbH may not be used to endorse or promote products
22 * derived from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
29 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
30 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
31 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
32 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
33 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35/*
36 * Written by Paul Popelka (paulp@uts.amdahl.com)
37 *
38 * You can do anything you want with this software, just don't say you wrote
39 * it, and don't remove this notice.
40 *
41 * This software is provided "as is".
42 *
43 * The author supplies this software to be publicly redistributed on the
44 * understanding that the author is not responsible for the correct
45 * functioning of this software in any circumstances and is not liable for
46 * any damages caused by this software.
47 *
48 * October 1992
49 */
50
51#include <sys/param.h>
52#include <sys/systm.h>
53#include <sys/mount.h>
54#include <sys/malloc.h>
55#include <sys/buf.h>
56#include <sys/vnode.h>
57#include <sys/lock.h>
58#include <sys/kernel.h> /* defines "time" */
59#include <sys/dirent.h>
60#include <sys/namei.h>
61
62#include <crypto/siphash.h>
63
64#include <msdosfs/bpb.h>
65#include <msdosfs/msdosfsmount.h>
66#include <msdosfs/direntry.h>
67#include <msdosfs/denode.h>
68#include <msdosfs/fat.h>
69
70u_int msdosfs_dehash(dev_t, uint32_t, uint32_t);
71
72struct denode **dehashtbl;
73SIPHASH_KEY dehashkey;
74u_long dehash; /* size of hash table - 1 */
75#define DEHASH(dev, dcl, doff)msdosfs_dehash((dev), (dcl), (doff)) msdosfs_dehash((dev), (dcl), (doff))
76
77static struct denode *msdosfs_hashget(dev_t, uint32_t, uint32_t);
78static int msdosfs_hashins(struct denode *);
79static void msdosfs_hashrem(struct denode *);
80
81int
82msdosfs_init(struct vfsconf *vfsp)
83{
84 dehashtbl = hashinit(initialvnodes / 2, M_MSDOSFSMNT59, M_WAITOK0x0001, &dehash);
85 arc4random_buf(&dehashkey, sizeof(dehashkey));
86 return (0);
87}
88
89u_int
90msdosfs_dehash(dev_t dev, uint32_t dirclust, uint32_t diroff)
91{
92 SIPHASH_CTX ctx;
93
94 SipHash24_Init(&ctx, &dehashkey)SipHash_Init((&ctx), (&dehashkey));
95 SipHash24_Update(&ctx, &dev, sizeof(dev))SipHash_Update((&ctx), 2, 4, (&dev), (sizeof(dev)));
96 SipHash24_Update(&ctx, &dirclust, sizeof(dirclust))SipHash_Update((&ctx), 2, 4, (&dirclust), (sizeof(dirclust
)))
;
97 SipHash24_Update(&ctx, &diroff, sizeof(diroff))SipHash_Update((&ctx), 2, 4, (&diroff), (sizeof(diroff
)))
;
98
99 return (SipHash24_End(&ctx)SipHash_End((&ctx), 2, 4) & dehash);
100}
101
102static struct denode *
103msdosfs_hashget(dev_t dev, uint32_t dirclust, uint32_t diroff)
104{
105 struct denode *dep;
106
107 for (;;)
108 for (dep = dehashtbl[DEHASH(dev, dirclust, diroff)msdosfs_dehash((dev), (dirclust), (diroff))]; ;
109 dep = dep->de_next) {
110 if (dep == NULL((void *)0))
111 return (NULL((void *)0));
112 if (dirclust == dep->de_dirclust &&
113 diroff == dep->de_diroffset &&
114 dev == dep->de_dev &&
115 dep->de_refcnt != 0) {
116 struct vnode *vp = DETOV(dep)((dep)->de_vnode);
117
118 if (!vget(vp, LK_EXCLUSIVE0x0001UL))
119 return (dep);
120 break;
121 }
122 }
123 /* NOTREACHED */
124}
125
126static int
127msdosfs_hashins(struct denode *dep)
128{
129 struct denode **depp, *deq;
130
131 depp = &dehashtbl[DEHASH(dep->de_dev, dep->de_dirclust,msdosfs_dehash((dep->de_dev), (dep->de_dirclust), (dep->
de_diroffset))
132 dep->de_diroffset)msdosfs_dehash((dep->de_dev), (dep->de_dirclust), (dep->
de_diroffset))
];
133
134 for (deq = *depp; deq; deq = deq->de_next) {
135 if (dep->de_dirclust == deq->de_dirclust &&
136 dep->de_diroffset == deq->de_diroffset &&
137 dep->de_dev == deq->de_dev &&
138 deq->de_refcnt != 0) {
139 return (EEXIST17);
140 }
141 }
142
143 if ((deq = *depp) != NULL((void *)0))
144 deq->de_prev = &dep->de_next;
145 dep->de_next = deq;
146 dep->de_prev = depp;
147 *depp = dep;
148 return (0);
149}
150
151static void
152msdosfs_hashrem(struct denode *dep)
153{
154 struct denode *deq;
155
156 if (dep->de_prev == NULL((void *)0))
157 return;
158
159 if ((deq = dep->de_next) != NULL((void *)0))
160 deq->de_prev = dep->de_prev;
161 *dep->de_prev = deq;
162#ifdef DIAGNOSTIC1
163 dep->de_next = NULL((void *)0);
164 dep->de_prev = NULL((void *)0);
165#endif
166}
167
168/*
169 * If deget() succeeds it returns with the gotten denode locked().
170 *
171 * pmp - address of msdosfsmount structure of the filesystem containing
172 * the denode of interest. The pm_dev field and the address of
173 * the msdosfsmount structure are used.
174 * dirclust - which cluster bp contains, if dirclust is 0 (root directory)
175 * diroffset is relative to the beginning of the root directory,
176 * otherwise it is cluster relative.
177 * diroffset - offset past begin of cluster of denode we want
178 * depp - returns the address of the gotten denode.
179 */
180int
181deget(struct msdosfsmount *pmp, uint32_t dirclust, uint32_t diroffset,
182 struct denode **depp)
183{
184 int error;
185 extern const struct vops msdosfs_vops;
186 struct direntry *direntptr;
187 struct denode *ldep;
188 struct vnode *nvp;
189 struct buf *bp;
190
191#ifdef MSDOSFS_DEBUG
192 printf("deget(pmp %p, dirclust %d, diroffset %x, depp %p)\n",
193 pmp, dirclust, diroffset, depp);
194#endif
195
196 /*
197 * On FAT32 filesystems, root is a (more or less) normal
198 * directory
199 */
200 if (FAT32(pmp)(pmp->pm_fatmask == 0x0fffffff) && dirclust == MSDOSFSROOT0)
201 dirclust = pmp->pm_rootdirblk;
202
203 /*
204 * See if the denode is in the denode cache. Use the location of
205 * the directory entry to compute the hash value. For subdir use
206 * address of "." entry. For root dir (if not FAT32) use cluster
207 * MSDOSFSROOT, offset MSDOSFSROOT_OFS
208 *
209 * NOTE: The check for de_refcnt > 0 below insures the denode being
210 * examined does not represent an unlinked but still open file.
211 * These files are not to be accessible even when the directory
212 * entry that represented the file happens to be reused while the
213 * deleted file is still open.
214 */
215retry:
216 ldep = msdosfs_hashget(pmp->pm_dev, dirclust, diroffset);
217 if (ldep) {
218 *depp = ldep;
219 return (0);
220 }
221
222 /*
223 * Directory entry was not in cache, have to create a vnode and
224 * copy it from the passed disk buffer.
225 */
226 /* getnewvnode() does a vref() on the vnode */
227 error = getnewvnode(VT_MSDOSFS, pmp->pm_mountp, &msdosfs_vops, &nvp);
228 if (error) {
229 *depp = 0;
230 return (error);
231 }
232 ldep = malloc(sizeof(*ldep), M_MSDOSFSNODE61, M_WAITOK0x0001 | M_ZERO0x0008);
233 rrw_init_flags(&ldep->de_lock, "denode", RWL_DUPOK | RWL_IS_VNODE)_rrw_init_flags(&ldep->de_lock, "denode", 0, ((void *)
0))
;
234 nvp->v_data = ldep;
235 ldep->de_vnode = nvp;
236 ldep->de_flag = 0;
237 ldep->de_devvp = 0;
238 ldep->de_lockf = 0;
239 ldep->de_dev = pmp->pm_dev;
240 ldep->de_dirclust = dirclust;
241 ldep->de_diroffset = diroffset;
242 fc_purge(ldep, 0); /* init the fat cache for this denode */
243
244 /*
245 * Insert the denode into the hash queue and lock the denode so it
246 * can't be accessed until we've read it in and have done what we
247 * need to it.
248 */
249 vn_lock(nvp, LK_EXCLUSIVE0x0001UL | LK_RETRY0x2000UL);
250 error = msdosfs_hashins(ldep);
251
252 if (error) {
253 vput (nvp);
254
255 if (error == EEXIST17)
256 goto retry;
257
258 return (error);
259 }
260
261 ldep->de_pmp = pmp;
262 ldep->de_devvp = pmp->pm_devvp;
263 ldep->de_refcnt = 1;
264 /*
265 * Copy the directory entry into the denode area of the vnode.
266 */
267 if ((dirclust == MSDOSFSROOT0
268 || (FAT32(pmp)(pmp->pm_fatmask == 0x0fffffff) && dirclust == pmp->pm_rootdirblk))
269 && diroffset == MSDOSFSROOT_OFS0x1fffffff) {
270 /*
271 * Directory entry for the root directory. There isn't one,
272 * so we manufacture one. We should probably rummage
273 * through the root directory and find a label entry (if it
274 * exists), and then use the time and date from that entry
275 * as the time and date for the root denode.
276 */
277 nvp->v_flag |= VROOT0x0001; /* should be further down XXX */
278
279 ldep->de_Attributes = ATTR_DIRECTORY0x10;
280 if (FAT32(pmp)(pmp->pm_fatmask == 0x0fffffff))
281 ldep->de_StartCluster = pmp->pm_rootdirblk;
282 /* de_FileSize will be filled in further down */
283 else {
284 ldep->de_StartCluster = MSDOSFSROOT0;
285 ldep->de_FileSize = pmp->pm_rootdirsize * pmp->pm_BytesPerSecpm_bpb.bpbBytesPerSec;
286 }
287 /*
288 * fill in time and date so that dos2unixtime() doesn't
289 * spit up when called from msdosfs_getattr() with root
290 * denode
291 */
292 ldep->de_CTime = 0x0000; /* 00:00:00 */
293 ldep->de_CTimeHundredth = 0;
294 ldep->de_CDate = (0 << DD_YEAR_SHIFT9) | (1 << DD_MONTH_SHIFT5)
295 | (1 << DD_DAY_SHIFT0);
296 /* Jan 1, 1980 */
297 ldep->de_ADate = ldep->de_CDate;
298 ldep->de_MTime = ldep->de_CTime;
299 ldep->de_MDate = ldep->de_CDate;
300 /* leave the other fields as garbage */
301 } else {
302 error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
303 if (error)
304 return (error);
305 DE_INTERNALIZE(ldep, direntptr)(bcopy((direntptr)->deName, (ldep)->de_Name, 8), bcopy(
(direntptr)->deExtension, (ldep)->de_Name + 8, 3), (ldep
)->de_Attributes = (direntptr)->deAttributes, (ldep)->
de_CTimeHundredth = (direntptr)->deCTimeHundredth, (ldep)->
de_CTime = *((u_int16_t *)((direntptr)->deCTime)), (ldep)->
de_CDate = *((u_int16_t *)((direntptr)->deCDate)), (ldep)->
de_ADate = *((u_int16_t *)((direntptr)->deADate)), (ldep)->
de_MTime = *((u_int16_t *)((direntptr)->deMTime)), (ldep)->
de_MDate = *((u_int16_t *)((direntptr)->deMDate)), (ldep)->
de_StartCluster = *((u_int16_t *)((direntptr)->deStartCluster
)), (ldep)->de_FileSize = *((u_int32_t *)((direntptr)->
deFileSize)), (((ldep)->de_pmp->pm_fatmask == 0x0fffffff
) ? (((ldep))->de_StartCluster |= *((u_int16_t *)(((direntptr
))->deHighClust)) << 16) : 0))
;
306 brelse(bp);
307 }
308
309 /*
310 * Fill in a few fields of the vnode and finish filling in the
311 * denode. Then return the address of the found denode.
312 */
313 if (ldep->de_Attributes & ATTR_DIRECTORY0x10) {
314 /*
315 * Since DOS directory entries that describe directories
316 * have 0 in the filesize field, we take this opportunity
317 * to find out the length of the directory and plug it into
318 * the denode structure.
319 */
320 uint32_t size;
321
322 nvp->v_type = VDIR;
323 if (ldep->de_StartCluster != MSDOSFSROOT0) {
324 error = pcbmap(ldep, CLUST_END0xffffffff, 0, &size, 0);
325 if (error == E2BIG7) {
326 ldep->de_FileSize = de_cn2off(pmp, size)((size) << (pmp)->pm_cnshift);
327 error = 0;
Value stored to 'error' is never read
328 } else if (error) {
329 printf("deget(): pcbmap returned %d\n", error);
330 return (error);
331 }
332 }
333 } else
334 nvp->v_type = VREG;
335 vref(ldep->de_devvp);
336 *depp = ldep;
337 return (0);
338}
339
340int
341deupdat(struct denode *dep, int waitfor)
342{
343 struct buf *bp;
344 struct direntry *dirp;
345 int error;
346 struct timespec ts;
347
348 if (DETOV(dep)((dep)->de_vnode)->v_mount->mnt_flag & MNT_RDONLY0x00000001)
349 return (0);
350 getnanotime(&ts);
351 DETIMES(dep, &ts, &ts, &ts)if ((dep)->de_flag & (0x0004 | 0x0008 | 0x0010)) { (dep
)->de_flag |= 0x0020; if ((dep)->de_flag & 0x0004) {
unix2dostime((&ts), &(dep)->de_MDate, &(dep)->
de_MTime, ((void *)0)); (dep)->de_Attributes |= 0x20; } if
(!((dep)->de_pmp->pm_flags & 0x04)) { if ((dep)->
de_flag & 0x0010) unix2dostime((&ts), &(dep)->
de_ADate, ((void *)0), ((void *)0)); if ((dep)->de_flag &
0x0008) unix2dostime((&ts), &(dep)->de_CDate, &
(dep)->de_CTime, &(dep)->de_CTimeHundredth); } (dep
)->de_flag &= ~(0x0004 | 0x0008 | 0x0010); }
;
352 if ((dep->de_flag & DE_MODIFIED0x0020) == 0)
353 return (0);
354 dep->de_flag &= ~DE_MODIFIED0x0020;
355 if (dep->de_Attributes & ATTR_DIRECTORY0x10)
356 return (0);
357 if (dep->de_refcnt <= 0)
358 return (0);
359 error = readde(dep, &bp, &dirp);
360 if (error)
361 return (error);
362 DE_EXTERNALIZE(dirp, dep)(bcopy((dep)->de_Name, (dirp)->deName, 8), bcopy((dep)->
de_Name + 8, (dirp)->deExtension, 3), (dirp)->deAttributes
= (dep)->de_Attributes, (dirp)->deLowerCase = 0x08 | 0x10
, (dirp)->deCTimeHundredth = (dep)->de_CTimeHundredth, (
*((u_int16_t *)((dirp)->deCTime)) = ((dep)->de_CTime)),
(*((u_int16_t *)((dirp)->deCDate)) = ((dep)->de_CDate)
), (*((u_int16_t *)((dirp)->deADate)) = ((dep)->de_ADate
)), (*((u_int16_t *)((dirp)->deMTime)) = ((dep)->de_MTime
)), (*((u_int16_t *)((dirp)->deMDate)) = ((dep)->de_MDate
)), (*((u_int16_t *)((dirp)->deStartCluster)) = ((dep)->
de_StartCluster)), (*((u_int32_t *)((dirp)->deFileSize)) =
(((dep)->de_Attributes & 0x10) ? 0 : (dep)->de_FileSize
)), (*((u_int16_t *)((dirp)->deHighClust)) = (((dep)->de_pmp
->pm_fatmask == 0x0fffffff) ? (dep)->de_StartCluster >>
16 : 0)))
;
363 if (waitfor)
364 return (bwrite(bp));
365 else {
366 bdwrite(bp);
367 return (0);
368 }
369}
370
371/*
372 * Truncate the file described by dep to the length specified by length.
373 */
374int
375detrunc(struct denode *dep, uint32_t length, int flags, struct ucred *cred,
376 struct proc *p)
377{
378 int error;
379 int allerror;
380 int vflags;
381 uint32_t eofentry;
382 uint32_t chaintofree = 0;
383 daddr_t bn;
384 int boff;
385 int isadir = dep->de_Attributes & ATTR_DIRECTORY0x10;
386 struct buf *bp;
387 struct msdosfsmount *pmp = dep->de_pmp;
388
389#ifdef MSDOSFS_DEBUG
390 printf("detrunc(): file %.11s, length %u, flags %d\n",
391 dep->de_Name, length, flags);
392#endif
393
394 /*
395 * Disallow attempts to truncate the root directory since it is of
396 * fixed size. That's just the way dos filesystems are. We use
397 * the VROOT bit in the vnode because checking for the directory
398 * bit and a startcluster of 0 in the denode is not adequate to
399 * recognize the root directory at this point in a file or
400 * directory's life.
401 */
402 if ((DETOV(dep)((dep)->de_vnode)->v_flag & VROOT0x0001) && !FAT32(pmp)(pmp->pm_fatmask == 0x0fffffff)) {
403 printf("detrunc(): can't truncate root directory, clust %u, offset %u\n",
404 dep->de_dirclust, dep->de_diroffset);
405 return (EINVAL22);
406 }
407
408 uvm_vnp_setsize(DETOV(dep)((dep)->de_vnode), length);
409
410 if (dep->de_FileSize < length)
411 return (deextend(dep, length, cred));
412
413 /*
414 * If the desired length is 0 then remember the starting cluster of
415 * the file and set the StartCluster field in the directory entry
416 * to 0. If the desired length is not zero, then get the number of
417 * the last cluster in the shortened file. Then get the number of
418 * the first cluster in the part of the file that is to be freed.
419 * Then set the next cluster pointer in the last cluster of the
420 * file to CLUST_EOFE.
421 */
422 if (length == 0) {
423 chaintofree = dep->de_StartCluster;
424 dep->de_StartCluster = 0;
425 eofentry = ~0;
426 } else {
427 error = pcbmap(dep, de_clcount(pmp, length)(((length) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift
)
- 1, 0,
428 &eofentry, 0);
429 if (error) {
430#ifdef MSDOSFS_DEBUG
431 printf("detrunc(): pcbmap fails %d\n", error);
432#endif
433 return (error);
434 }
435 }
436
437 fc_purge(dep, de_clcount(pmp, length)(((length) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift
)
);
438
439 /*
440 * If the new length is not a multiple of the cluster size then we
441 * must zero the tail end of the new last cluster in case it
442 * becomes part of the file again because of a seek.
443 */
444 if ((boff = length & pmp->pm_crbomask) != 0) {
445 if (isadir) {
446 bn = cntobn(pmp, eofentry)((((eofentry)-2) << (((pmp))->pm_cnshift - ((pmp))->
pm_bnshift)) + (pmp)->pm_firstcluster)
;
447 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, &bp);
448 } else {
449 bn = de_blk(pmp, length)((((((length)) >> ((pmp))->pm_cnshift)) << ((pmp
)->pm_cnshift - (pmp)->pm_bnshift)))
;
450 error = bread(DETOV(dep)((dep)->de_vnode), bn, pmp->pm_bpcluster, &bp);
451 }
452 if (error) {
453 brelse(bp);
454#ifdef MSDOSFS_DEBUG
455 printf("detrunc(): bread fails %d\n", error);
456#endif
457 return (error);
458 }
459 uvm_vnp_uncache(DETOV(dep)((dep)->de_vnode));
460 /*
461 * is this the right place for it?
462 */
463 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff)__builtin_bzero((bp->b_data + boff), (pmp->pm_bpcluster
- boff))
;
464 if (flags & IO_SYNC0x04)
465 bwrite(bp);
466 else
467 bdwrite(bp);
468 }
469
470 /*
471 * Write out the updated directory entry. Even if the update fails
472 * we free the trailing clusters.
473 */
474 dep->de_FileSize = length;
475 if (!isadir)
476 dep->de_flag |= DE_UPDATE0x0004|DE_MODIFIED0x0020;
477 vflags = (length > 0 ? V_SAVE0x0001 : 0) | V_SAVEMETA0x0002;
478 vinvalbuf(DETOV(dep)((dep)->de_vnode), vflags, cred, p, 0, INFSLP0xffffffffffffffffULL);
479 allerror = deupdat(dep, 1);
480#ifdef MSDOSFS_DEBUG
481 printf("detrunc(): allerror %d, eofentry %d\n",
482 allerror, eofentry);
483#endif
484
485 /*
486 * If we need to break the cluster chain for the file then do it
487 * now.
488 */
489 if (eofentry != ~0) {
490 error = fatentry(FAT_GET_AND_SET(0x0001 | 0x0002), pmp, eofentry,
491 &chaintofree, CLUST_EOFE0xffffffff);
492 if (error) {
493#ifdef MSDOSFS_DEBUG
494 printf("detrunc(): fatentry errors %d\n", error);
495#endif
496 return (error);
497 }
498 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),(dep)->de_fc[1].fc_frcn = ((length - 1) >> (pmp)->
pm_cnshift); (dep)->de_fc[1].fc_fsrcn = eofentry;
499 eofentry)(dep)->de_fc[1].fc_frcn = ((length - 1) >> (pmp)->
pm_cnshift); (dep)->de_fc[1].fc_fsrcn = eofentry;
;
500 }
501
502 /*
503 * Now free the clusters removed from the file because of the
504 * truncation.
505 */
506 if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree)((((chaintofree) | ~(pmp)->pm_fatmask) & 0xfffffff8) ==
0xfffffff8)
)
507 freeclusterchain(pmp, chaintofree);
508
509 return (allerror);
510}
511
512/*
513 * Extend the file described by dep to length specified by length.
514 */
515int
516deextend(struct denode *dep, uint32_t length, struct ucred *cred)
517{
518 struct msdosfsmount *pmp = dep->de_pmp;
519 uint32_t count;
520 int error;
521
522 /*
523 * The root of a DOS filesystem cannot be extended.
524 */
525 if ((DETOV(dep)((dep)->de_vnode)->v_flag & VROOT0x0001) && !FAT32(pmp)(pmp->pm_fatmask == 0x0fffffff))
526 return (EINVAL22);
527
528 /*
529 * Directories cannot be extended.
530 */
531 if (dep->de_Attributes & ATTR_DIRECTORY0x10)
532 return (EISDIR21);
533
534 if (length <= dep->de_FileSize)
535 panic("deextend: file too large");
536
537 /*
538 * Compute the number of clusters to allocate.
539 */
540 count = de_clcount(pmp, length)(((length) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift
)
- de_clcount(pmp, dep->de_FileSize)(((dep->de_FileSize) + (pmp)->pm_bpcluster - 1) >>
(pmp)->pm_cnshift)
;
541 if (count > 0) {
542 if (count > pmp->pm_freeclustercount)
543 return (ENOSPC28);
544 error = extendfile(dep, count, NULL((void *)0), NULL((void *)0), DE_CLEAR1);
545 if (error) {
546 /* truncate the added clusters away again */
547 (void) detrunc(dep, dep->de_FileSize, 0, cred, curproc({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r"
(__ci) :"n" (__builtin_offsetof(struct cpu_info, ci_self)));
__ci;})->ci_curproc
);
548 return (error);
549 }
550 }
551
552 dep->de_FileSize = length;
553 dep->de_flag |= DE_UPDATE0x0004|DE_MODIFIED0x0020;
554 return (deupdat(dep, 1));
555}
556
557/*
558 * Move a denode to its correct hash queue after the file it represents has
559 * been moved to a new directory.
560 */
561void
562reinsert(struct denode *dep)
563{
564 /*
565 * Fix up the denode cache. If the denode is for a directory,
566 * there is nothing to do since the hash is based on the starting
567 * cluster of the directory file and that hasn't changed. If for a
568 * file the hash is based on the location of the directory entry,
569 * so we must remove it from the cache and re-enter it with the
570 * hash based on the new location of the directory entry.
571 */
572 if (dep->de_Attributes & ATTR_DIRECTORY0x10)
573 return;
574 msdosfs_hashrem(dep);
575 msdosfs_hashins(dep);
576}
577
578int
579msdosfs_reclaim(void *v)
580{
581 struct vop_reclaim_args *ap = v;
582 struct vnode *vp = ap->a_vp;
583 struct denode *dep = VTODE(vp)((struct denode *)(vp)->v_data);
584#ifdef DIAGNOSTIC1
585 extern int prtactive;
586
587 if (prtactive && vp->v_usecount != 0)
588 vprint("msdosfs_reclaim(): pushing active", vp);
589#endif
590
591#ifdef MSDOSFS_DEBUG
592 printf("msdosfs_reclaim(): dep %p, file %.11s, refcnt %ld\n",
593 dep, dep->de_Name, dep->de_refcnt);
594#endif
595
596 /*
597 * Remove the denode from its hash chain.
598 */
599 msdosfs_hashrem(dep);
600 /*
601 * Purge old data structures associated with the denode.
602 */
603 cache_purge(vp);
604 if (dep->de_devvp) {
605 vrele(dep->de_devvp);
606 dep->de_devvp = 0;
607 }
608#if 0 /* XXX */
609 dep->de_flag = 0;
610#endif
611 free(dep, M_MSDOSFSNODE61, 0);
612 vp->v_data = NULL((void *)0);
613 return (0);
614}
615
616int
617msdosfs_inactive(void *v)
618{
619 struct vop_inactive_args *ap = v;
620 struct vnode *vp = ap->a_vp;
621 struct denode *dep = VTODE(vp)((struct denode *)(vp)->v_data);
622 int error;
623#ifdef DIAGNOSTIC1
624 extern int prtactive;
625
626 if (prtactive && vp->v_usecount != 0)
627 vprint("msdosfs_inactive(): pushing active", vp);
628#endif
629
630#ifdef MSDOSFS_DEBUG
631 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep,
632 dep->de_Name[0]);
633#endif
634
635 error = 0;
636
637 /*
638 * Get rid of denodes related to stale file handles.
639 */
640 if (dep->de_Name[0] == SLOT_DELETED0xe5)
641 goto out;
642
643 /*
644 * If the file has been deleted and it is on a read/write
645 * filesystem, then truncate the file, and mark the directory slot
646 * as empty. (This may not be necessary for the dos filesystem.)
647 */
648#ifdef MSDOSFS_DEBUG
649 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, "
650 "MNT_RDONLY %x\n", dep, dep->de_refcnt, vp->v_mount->mnt_flag,
651 MNT_RDONLY0x00000001);
652#endif
653 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY0x00000001) == 0) {
654 error = detrunc(dep, (uint32_t)0, 0, NOCRED((struct ucred *)-1), ap->a_p);
655 dep->de_Name[0] = SLOT_DELETED0xe5;
656 }
657 deupdat(dep, 0);
658
659out:
660 VOP_UNLOCK(vp);
661 /*
662 * If we are done with the denode, reclaim it
663 * so that it can be reused immediately.
664 */
665#ifdef MSDOSFS_DEBUG
666 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n",
667 vp->v_usecount, dep->de_Name[0]);
668#endif
669 if (dep->de_Name[0] == SLOT_DELETED0xe5)
670 vrecycle(vp, ap->a_p);
671 return (error);
672}