I hope that VFAT is safe wrt dcache now (and it got rid of quite a few
bugs of its own ;-). Please, apply the patch below. It's against -pre7.
Size - ~2K for VFS part + ~30K for VFAT one.
TIA,
Al
Patch follows:
--- linux.vanilla/fs/namei.c Wed Dec 30 20:24:30 1998
+++ linux.bird-stable/fs/namei.c Mon Jan 11 08:10:19 1999
@@ -935,7 +935,15 @@
*
* if it cannot handle the case of removing a directory
* that is still in use by something else..
+ *
+ * Yeah, but if we had it dropped from the very beginning
+ * we may end deep in it. It should be dealt with by caller.
+ * For the time being return -ENOENT from here.
*/
+
+ if (list_empty(&dentry->d_hash))
+ return -ENOENT;
+
switch (dentry->d_count) {
default:
shrink_dcache_parent(dentry);
@@ -1213,6 +1221,18 @@
{
int error;
int isdir;
+
+ if (list_empty(&new_dentry->d_hash)||list_empty(&old_dentry->d_hash)) {
+ /*
+ * Damn. We still have no proper mechanism to deal with such
+ * things. Return -ENOENT for now, passing the request to
+ * filesystem may result in massive lossage. We should deal
+ * with that stuff above this layer, not below.
+ */
+printk( KERN_WARNING
+"vfs_rename: KLUDGE. RACE HAPPENED - one of dentries unhashed. ENOENT\n");
+ return -ENOENT;
+ }
isdir = S_ISDIR(old_dentry->d_inode->i_mode);
--- linux.vanilla/fs/dcache.c Mon Jan 11 08:08:57 1999
+++ linux.bird-stable/fs/dcache.c Mon Jan 11 08:10:18 1999
@@ -729,6 +729,14 @@
* Careful with the hash switch. The hash switch depends on
* the fact that any list-entry can be a head of the list.
* Think about it.
+ *
+ * We'll get a lot of mess if the target will be unhashed.
+ * When we call d_move we *want* to make dentry available
+ * under the new name, thus insert it into the right hash
+ * no matter what. It's a bit fragile, but we call it only
+ * when underlying fs had already done all modifications,
+ * so if there is another hashed dentry with the same name
+ * it's too late anyway.
*/
void d_move(struct dentry * dentry, struct dentry * target)
{
@@ -737,7 +745,7 @@
/* Move the dentry to the target hash queue */
list_del(&dentry->d_hash);
- list_add(&dentry->d_hash, &target->d_hash);
+ list_add(&dentry->d_hash, d_hash(target->d_parent,target->d_name.hash));
/* Unhash the target: dput() will then get rid of it */
list_del(&target->d_hash);
--- linux.vanilla/include/linux/dcache.h Thu Dec 31 20:06:05 1998
+++ linux.bird-stable/include/linux/dcache.h Mon Jan 11 08:10:19 1999
@@ -178,6 +178,29 @@
extern void dput(struct dentry *);
+/*
+ * d_try_drop() tries to ensure that nobody else will
+ * have/get a reference on dentry. If we have any children
+ * it tries to do shrink_dcache_parent() to get rid of
+ * them and if it gets d_count==1 it unhashes the dentry.
+ * It is safe to call only if the parent is locked and we
+ * have an atomicity wrt other dcache users. Currently the
+ * later is guaranteed by the kernel_lock.
+ * Used when we *need* to become the sole owners of
+ * dentry and let nobody in even if we'll sleep (rename()
+ * provides such example; there may be other ones).
+ */
+static __inline__ int d_try_drop(struct dentry * dentry)
+{
+ if (!list_empty(&dentry->d_subdirs)) {
+ shrink_dcache_parent(dentry);
+ if (dentry->d_count>1)
+ return 0; /* failed */
+ }
+ d_drop(dentry);
+ return 1;
+}
+
#endif /* __KERNEL__ */
#endif /* __LINUX_DCACHE_H */
--- linux.vanilla/fs/vfat/namei.c Mon Jan 11 08:08:33 1999
+++ linux.bird-stable/fs/vfat/namei.c Sun Jan 10 22:25:20 1999
@@ -395,7 +395,7 @@
static char replace_chars[] = "[];,+=";
static int vfat_find(struct inode *dir,struct qstr* name,
- int find_long,int new_filename,int is_dir,
+ int new_filename,int is_dir,
struct vfat_slot_info *sinfo_out);
/* Checks the validity of a long MS-DOS filename */
@@ -446,12 +446,11 @@
static int vfat_valid_shortname(const char *name,int len,
int dot_dirs, int utf8)
{
- const char *walk, **reserved;
+ const char *walk;
unsigned char c;
int space;
int baselen;
- if (IS_FREE(name)) return -EINVAL;
if (name[0] == '.' && (len == 1 || (len == 2 && name[1] == '.'))) {
if (!dot_dirs) return -EEXIST;
return 1;
@@ -463,11 +462,9 @@
c = *walk++;
len--;
if (utf8 && (c & 0x80)) return -EINVAL;
- if (strchr(bad_chars,c)) return -EINVAL;
if (strchr(replace_chars,c)) return -EINVAL;
if (c >= 'A' && c <= 'Z') return -EINVAL;
- if (c < ' ' || c == ':' || c == '\\') return -EINVAL;
- if ((walk == name) && (c == 0xE5)) c = 0x05;
+ if (c < ' '|| c==':') return -EINVAL;
if (c == '.') break;
space = c == ' ';
}
@@ -477,51 +474,52 @@
len--;
if (c != '.') return -EINVAL;
}
- while (c != '.' && len--) c = *walk++;
baselen = walk - name;
if (c == '.') {
baselen--;
if (len >= 4) return -EINVAL;
- while (len > 0 && walk-name < (MSDOS_NAME+1)) {
+ while (len > 0) {
c = *walk++;
len--;
if (utf8 && (c & 0x80)) return -EINVAL;
- if (strchr(bad_chars,c)) return -EINVAL;
if (strchr(replace_chars,c))
return -EINVAL;
- if (c < ' ' || c == ':' || c == '\\' || c == '.')
+ if (c < ' ' || c == '.'|| c==':')
return -EINVAL;
if (c >= 'A' && c <= 'Z') return -EINVAL;
space = c == ' ';
}
if (space) return -EINVAL;
- if (len) return -EINVAL;
- }
- if (baselen == 3) {
- for (reserved = reserved3_names; *reserved; reserved++)
- if (!strnicmp(name,*reserved,baselen)) return -EINVAL;
- } else if (baselen == 4) {
- for (reserved = reserved4_names; *reserved; reserved++)
- if (!strnicmp(name,*reserved,baselen)) return -EINVAL;
}
return 0;
}
-/* Takes a short filename and converts it to a formatted MS-DOS filename.
- * If the short filename is not a valid MS-DOS filename, an error is
- * returned. The formatted short filename is returned in 'res'.
- */
+static int vfat_find_form(struct inode *dir,char *name)
+{
+ struct msdos_dir_entry *de;
+ struct buffer_head *bh = NULL;
+ loff_t pos = 0;
+
+ while(fat_get_entry(dir, &pos, &bh, &de) >= 0) {
+ if (de->attr == ATTR_EXT)
+ continue;
+ if (memcmp(de->name,name,MSDOS_NAME))
+ continue;
+ brelse(bh);
+ return 0;
+ }
+ brelse(bh);
+ return -ENOENT;
+}
static int vfat_format_name(const char *name,int len,char *res,
int dot_dirs,int utf8)
{
char *walk;
- const char **reserved;
unsigned char c;
int space;
- if (IS_FREE(name)) return -EINVAL;
if (name[0] == '.' && (len == 1 || (len == 2 && name[1] == '.'))) {
if (!dot_dirs) return -EEXIST;
memset(res+1,' ',10);
@@ -530,36 +528,25 @@
}
space = 1; /* disallow names starting with a dot */
- c = 0;
- for (walk = res; len && walk-res < 8; walk++) {
- c = *name++;
- len--;
+ for (walk = res; len-- && (c=*name++)!='.' ; walk++) {
+ if (walk-res == 8) return -EINVAL;
if (utf8 && (c & 0x80)) return -EINVAL;
- if (strchr(bad_chars,c)) return -EINVAL;
if (strchr(replace_chars,c)) return -EINVAL;
if (c >= 'A' && c <= 'Z') return -EINVAL;
- if (c < ' ' || c == ':' || c == '\\') return -EINVAL;
- if (c == '.') break;
+ if (c < ' '|| c==':') return -EINVAL;
space = c == ' ';
*walk = c >= 'a' && c <= 'z' ? c-32 : c;
}
if (space) return -EINVAL;
- if (len && c != '.') {
- c = *name++;
- len--;
- if (c != '.') return -EINVAL;
- }
- while (c != '.' && len--) c = *name++;
- if (c == '.') {
+ if (len >= 0) {
while (walk-res < 8) *walk++ = ' ';
while (len > 0 && walk-res < MSDOS_NAME) {
c = *name++;
len--;
if (utf8 && (c & 0x80)) return -EINVAL;
- if (strchr(bad_chars,c)) return -EINVAL;
if (strchr(replace_chars,c))
return -EINVAL;
- if (c < ' ' || c == ':' || c == '\\' || c == '.')
+ if (c < ' ' || c == '.'|| c==':')
return -EINVAL;
if (c >= 'A' && c <= 'Z') return -EINVAL;
space = c == ' ';
@@ -569,10 +556,6 @@
if (len) return -EINVAL;
}
while (walk-res < MSDOS_NAME) *walk++ = ' ';
- for (reserved = reserved3_names; *reserved; reserved++)
- if (!strnicmp(res,*reserved,8)) return -EINVAL;
- for (reserved = reserved4_names; *reserved; reserved++)
- if (!strnicmp(res,*reserved,8)) return -EINVAL;
return 0;
}
@@ -587,16 +570,12 @@
{
const char *ip, *ext_start, *end;
char *p;
- int sz, extlen, baselen, totlen;
+ int sz, extlen, baselen;
char msdos_name[13];
char base[9], ext[4];
int i;
- int res;
- int spaces;
char buf[8];
- struct vfat_slot_info sinfo;
const char *name_start;
- struct qstr qname;
PRINTK2(("Entering vfat_create_shortname: name=%s, len=%d\n", name, len));
sz = 0; /* Make compiler happy */
@@ -606,31 +585,25 @@
* shortname if is were all capitalized. However, do not
* allow spaces in short names because Win95 scandisk does
* not like that */
- res = 0;
- for (i = 0, p = msdos_name, ip = name; i < len; i++, p++, ip++)
- {
- if (*ip == ' ') {
- res = -1;
- break;
+ for (i = 0, p = msdos_name, ip = name; ; i++, p++, ip++) {
+ if (i == len) {
+ if (vfat_format_name(msdos_name,
+ len, name_res, 1, utf8) < 0)
+ break;
+ PRINTK3(("vfat_create_shortname 1\n"));
+ if (vfat_find_form(dir, name_res) < 0)
+ return 0;
+ return -EEXIST;
}
+
+ if (*ip == ' ')
+ break;
if (*ip >= 'A' && *ip <= 'Z') {
*p = *ip + 32;
} else {
*p = *ip;
}
}
- if (res == 0) {
- res = vfat_format_name(msdos_name, len, name_res, 1, utf8);
- }
- if (res > -1) {
- PRINTK3(("vfat_create_shortname 1\n"));
- qname.name=msdos_name;
- qname.len=len;
- res = vfat_find(dir, &qname, 0, 0, 0, &sinfo);
- PRINTK3(("vfat_create_shortname 2\n"));
- if (res > -1) return -EEXIST;
- return 0;
- }
}
PRINTK3(("vfat_create_shortname 3\n"));
@@ -675,8 +648,8 @@
*p++ = '_';
baselen++;
} else if (!strchr(skip_chars, *ip)) {
- if (*ip >= 'A' && *ip <= 'Z') {
- *p = *ip + 32;
+ if (*ip >= 'a' && *ip <= 'z') {
+ *p = *ip - 32;
} else {
*p = *ip;
}
@@ -689,17 +662,15 @@
return -EINVAL;
}
- spaces = 8 - baselen;
-
+ extlen = 0;
if (ext_start) {
- extlen = 0;
for (p = ext, ip = ext_start; extlen < 3 && ip < end; ip++) {
if (utf8 && (*ip & 0x80)) {
*p++ = '_';
extlen++;
} else if (!strchr(skip_chars, *ip)) {
- if (*ip >= 'A' && *ip <= 'Z') {
- *p = *ip + 32;
+ if (*ip >= 'a' && *ip <= 'z') {
+ *p = *ip - 32;
} else {
*p = *ip;
}
@@ -708,74 +679,57 @@
p++;
}
}
- } else {
- extlen = 0;
}
ext[extlen] = '\0';
base[baselen] = '\0';
- strcpy(msdos_name, base);
- msdos_name[baselen] = '.';
- strcpy(&msdos_name[baselen+1], ext);
+ /* Yes, it can happen. ".\xe5" would do it. */
+ if (IS_FREE(base))
+ base[0]='_';
+
+ /* OK, at this point we know that base is not longer than 8 symbols,
+ * ext is not longer than 3, base is nonempty, both don't contain
+ * any bad symbols (lowercase transformed to uppercase).
+ */
- totlen = baselen + extlen + (extlen > 0);
- res = 0;
- if (MSDOS_SB(dir->i_sb)->options.numtail == 0) {
- qname.name=msdos_name;
- qname.len=totlen;
- res = vfat_find(dir, &qname, 0, 0, 0, &sinfo);
- }
+ memset(name_res, ' ', MSDOS_NAME);
+ memcpy(name_res,base,baselen);
+ memcpy(name_res+8,ext,extlen);
+ if (MSDOS_SB(dir->i_sb)->options.numtail == 0)
+ if (vfat_find_form(dir, name_res) < 0)
+ return 0;
- if (res > -1) {
- /*
- * Try to find a unique extension. This used to
- * iterate through all possibilities sequentially,
- * but that gave extremely bad performance. Windows
- * only tries a few cases before using random
- * values for part of the base.
- */
+ /*
+ * Try to find a unique extension. This used to
+ * iterate through all possibilities sequentially,
+ * but that gave extremely bad performance. Windows
+ * only tries a few cases before using random
+ * values for part of the base.
+ */
- if (2 > spaces) {
- baselen = baselen - (2 - spaces);
- spaces = 2;
- }
- msdos_name[baselen] = '~';
- msdos_name[baselen+2] = '.';
- strcpy(&msdos_name[baselen+3], ext);
- totlen = baselen + 2 + extlen + (extlen > 0);
- qname.name=msdos_name;
- qname.len=totlen;
- for (i = 1; res > -1 && i < 10; i++) {
- strncpy(msdos_name, base, baselen);
- msdos_name[baselen+1] = i + '0';
- res = vfat_find(dir, &qname, 0, 0, 0, &sinfo);
- }
- }
- if (res > -1) {
- i = jiffies & 0xffff;
- sz = (jiffies >> 16) & 0x7;
- if (6 > spaces) {
- baselen = baselen - (6 - spaces);
- spaces = 6;
- }
- msdos_name[baselen+4] = '~';
- msdos_name[baselen+5] = '1' + sz;
- msdos_name[baselen+6] = '.';
- strcpy(&msdos_name[baselen+7], ext);
- totlen = baselen + 6 + extlen + (extlen > 0);
- qname.name=msdos_name;
- qname.len=totlen;
- while (res > -1) {
- sprintf(buf, "%04x", i);
- memcpy(&msdos_name[baselen], buf, 4);
- msdos_name[12] = 0;
- res = vfat_find(dir, &qname, 0, 0, 0, &sinfo);
- i -= 11;
- }
+ if (baselen>6)
+ baselen = 6;
+ name_res[baselen] = '~';
+ for (i = 1; i < 10; i++) {
+ name_res[baselen+1] = i + '0';
+ if (vfat_find_form(dir, name_res) < 0)
+ return 0;
}
- res = vfat_format_name(msdos_name, totlen, name_res, 1, utf8);
- return res;
+ i = jiffies & 0xffff;
+ sz = (jiffies >> 16) & 0x7;
+ if (baselen>2)
+ baselen = 2;
+ name_res[baselen+4] = '~';
+ name_res[baselen+5] = '1' + sz;
+ while (1) {
+ sprintf(buf, "%04X", i);
+ memcpy(&name_res[baselen], buf, 4);
+ if (vfat_find_form(dir, name_res) < 0)
+ break;
+ i -= 11;
+ }
+ return 0;
}
static loff_t vfat_find_free_slots(struct inode *dir,int slots)
@@ -996,6 +950,10 @@
strncpy(de->name, MSDOS_DOT, MSDOS_NAME);
} else {
PRINTK3(("vfat_build_slots 4\n"));
+ res = vfat_valid_longname(name, len, 1, xlate);
+ if (res < 0) {
+ return res;
+ }
res = vfat_valid_shortname(name, len, 1, utf8);
if (res > -1) {
PRINTK3(("vfat_build_slots 5a\n"));
@@ -1007,11 +965,6 @@
return res;
}
- res = vfat_valid_longname(name, len, 1, xlate);
- if (res < 0) {
- return res;
- }
-
*is_long = 1;
return vfat_fill_long_slots(ds, name, len, msdos_name,
@@ -1066,7 +1019,7 @@
}
static int vfat_find(struct inode *dir,struct qstr* qname,
- int find_long, int new_filename,int is_dir,struct vfat_slot_info *sinfo_out)
+ int new_filename,int is_dir,struct vfat_slot_info *sinfo_out)
{
struct super_block *sb = dir->i_sb;
struct vfat_find_info vf;
@@ -1096,7 +1049,7 @@
vf.found = 0;
vf.posix = MSDOS_SB(sb)->options.posixfs;
vf.anycase = (MSDOS_SB(sb)->options.name_check != 's');
- res = fat_readdirx(dir,&fil,(void *)&vf,vfat_readdir_cb,NULL,1,find_long,0);
+ res = fat_readdirx(dir,&fil,(void *)&vf,vfat_readdir_cb,NULL,1,1,0);
PRINTK3(("vfat_find: Debug 1\n"));
if (res < 0) goto cleanup;
if (vf.found) {
@@ -1117,75 +1070,70 @@
}
PRINTK3(("vfat_find: Debug 3\n"));
- if (!vf.found && !new_filename) {
+ if (!new_filename) {
res = -ENOENT;
goto cleanup;
}
res = vfat_build_slots(dir, qname->name, vf.len, ds,
&slots, &is_long);
+ /* Here we either have is_long and slots>=0 or slots==1 */
if (res < 0) goto cleanup;
de = (struct msdos_dir_entry *) ds;
bh = NULL;
- if (new_filename) {
- PRINTK3(("vfat_find: create file 1\n"));
- if (is_long) slots++;
- offset = vfat_find_free_slots(dir, slots);
- if (offset < 0) {
- res = offset;
+
+ PRINTK3(("vfat_find: create file 1\n"));
+ if (is_long) slots++;
+ offset = vfat_find_free_slots(dir, slots);
+ if (offset < 0) {
+ res = offset;
+ goto cleanup;
+ }
+
+ PRINTK3(("vfat_find: create file 2\n"));
+ /* Now create the new entry */
+ bh = NULL;
+ for (slot = 0, ps = ds; slot < slots; slot++, ps++) {
+ PRINTK3(("vfat_find: create file 3, slot=%d\n",slot));
+ sinfo_out->ino = fat_get_entry(dir,&offset,&bh,&de);
+ if (sinfo_out->ino < 0) {
+ PRINTK3(("vfat_find: problem\n"));
+ res = sinfo_out->ino;
goto cleanup;
}
+ memcpy(de, ps, sizeof(struct msdos_dir_slot));
+ fat_mark_buffer_dirty(sb, bh, 1);
+ }
- PRINTK3(("vfat_find: create file 2\n"));
- /* Now create the new entry */
- bh = NULL;
- for (slot = 0, ps = ds; slot < slots; slot++, ps++) {
- PRINTK3(("vfat_find: create file 3, slot=%d\n",slot));
- sinfo_out->ino = fat_get_entry(dir,&offset,&bh,&de);
- if (sinfo_out->ino < 0) {
- PRINTK3(("vfat_find: problem\n"));
- res = sinfo_out->ino;
- goto cleanup;
- }
- memcpy(de, ps, sizeof(struct msdos_dir_slot));
- fat_mark_buffer_dirty(sb, bh, 1);
- }
+ PRINTK3(("vfat_find: create file 4\n"));
+ dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME;
+ mark_inode_dirty(dir);
- PRINTK3(("vfat_find: create file 4\n"));
- dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME;
- mark_inode_dirty(dir);
-
- PRINTK3(("vfat_find: create file 5\n"));
-
- fat_date_unix2dos(dir->i_mtime,&de->time,&de->date);
- de->ctime_ms = 0;
- de->ctime = de->time;
- de->adate = de->cdate = de->date;
- de->start = 0;
- de->starthi = 0;
- de->size = 0;
- de->attr = is_dir ? ATTR_DIR : ATTR_ARCH;
- de->lcase = CASE_LOWER_BASE | CASE_LOWER_EXT;
+ PRINTK3(("vfat_find: create file 5\n"));
+ fat_date_unix2dos(dir->i_mtime,&de->time,&de->date);
+ de->ctime_ms = 0;
+ de->ctime = de->time;
+ de->adate = de->cdate = de->date;
+ de->start = 0;
+ de->starthi = 0;
+ de->size = 0;
+ de->attr = is_dir ? ATTR_DIR : ATTR_ARCH;
+ de->lcase = CASE_LOWER_BASE | CASE_LOWER_EXT;
- fat_mark_buffer_dirty(sb, bh, 1);
- fat_brelse(sb, bh);
- sinfo_out->is_long = (slots > 1) ? 1 : 0;
- if (sinfo_out->is_long) {
- sinfo_out->long_slots = slots - 1;
- } else {
- sinfo_out->long_slots = 0;
- }
- sinfo_out->total_slots = slots;
- sinfo_out->shortname_offset = offset - sizeof(struct msdos_dir_slot);
- sinfo_out->longname_offset = offset - sizeof(struct msdos_dir_slot) * slots;
- res = 0;
- } else {
- res = -ENOENT;
- }
+ fat_mark_buffer_dirty(sb, bh, 1);
+ fat_brelse(sb, bh);
+
+ /* slots can't be less than 1 */
+ sinfo_out->is_long = (slots > 1);
+ sinfo_out->long_slots = slots - 1;
+ sinfo_out->total_slots = slots;
+ sinfo_out->shortname_offset = offset - sizeof(struct msdos_dir_slot);
+ sinfo_out->longname_offset = offset - sizeof(struct msdos_dir_slot) * slots;
+ res = 0;
cleanup:
kfree(ds);
@@ -1206,7 +1154,7 @@
dentry->d_op = &vfat_dentry_ops[table];
result = NULL;
- if ((res = vfat_find(dir,&dentry->d_name,1,0,0,&sinfo)) < 0) {
+ if ((res = vfat_find(dir,&dentry->d_name,0,0,&sinfo)) < 0) {
result = NULL;
table++;
goto error;
@@ -1242,7 +1190,7 @@
*result=0;
PRINTK1(("vfat_create_entry: Entering\n"));
- res = vfat_find(dir, qname, 1, 1, is_dir, &sinfo);
+ res = vfat_find(dir, qname, 1, is_dir, &sinfo);
if (res < 0) {
return res;
}
@@ -1387,9 +1335,6 @@
struct buffer_head *bh;
struct msdos_dir_entry *de;
- if (dir->i_count > 1) {
- return -EBUSY;
- }
if (MSDOS_I(dir)->i_start) { /* may be zero in mkdir */
pos = 0;
bh = NULL;
@@ -1410,88 +1355,52 @@
return 0;
}
-static int vfat_rmdir_free_ino(struct inode *dir,struct buffer_head *bh,
- struct msdos_dir_entry *de,struct dentry* dentry)
+static void vfat_free_ino(struct inode *dir,struct buffer_head *bh,
+ struct msdos_dir_entry *de,struct inode* victim)
{
struct super_block *sb = dir->i_sb;
- int res;
-
- if (!list_empty(&dentry->d_hash))
- return -EBUSY;
-
- res = vfat_empty(dentry->d_inode);
- if (res) {
- return res;
- }
- dentry->d_inode->i_nlink = 0;
- dentry->d_inode->i_mtime = dir->i_mtime = CURRENT_TIME;
- dentry->d_inode->i_atime = dir->i_atime = CURRENT_TIME;
- dir->i_nlink--;
- mark_inode_dirty(dir);
- mark_inode_dirty(dentry->d_inode);
- de->name[0] = DELETED_FLAG;
- fat_mark_buffer_dirty(sb, bh, 1);
-
- return 0;
-}
-
-static int vfat_unlink_free_ino(struct inode *dir,struct buffer_head *bh,
- struct msdos_dir_entry *de,struct dentry* dentry,int nospc)
-{
- struct super_block *sb = dir->i_sb;
- if ((!S_ISREG(dentry->d_inode->i_mode) && nospc) ||
- IS_IMMUTABLE(dentry->d_inode)) {
- return -EPERM;
- }
- dentry->d_inode->i_nlink = 0;
- dentry->d_inode->i_mtime = dir->i_mtime = CURRENT_TIME;
- dentry->d_inode->i_atime = dir->i_atime = CURRENT_TIME;
+ victim->i_nlink = 0;
+ victim->i_mtime = dir->i_mtime = CURRENT_TIME;
+ victim->i_atime = dir->i_atime = CURRENT_TIME;
dir->i_version = ++event;
- MSDOS_I(dentry->d_inode)->i_busy = 1;
+ MSDOS_I(victim)->i_busy = 1;
mark_inode_dirty(dir);
- mark_inode_dirty(dentry->d_inode);
+ mark_inode_dirty(victim);
de->name[0] = DELETED_FLAG;
fat_mark_buffer_dirty(sb, bh, 1);
-
- return 0;
}
static int vfat_remove_entry(struct inode *dir,struct vfat_slot_info *sinfo,
- struct buffer_head **bh,struct dentry* dentry,
- int is_dir,int nospc)
+ struct inode* victim)
{
struct super_block *sb = dir->i_sb;
loff_t offset;
+ struct buffer_head *bh=NULL;
struct msdos_dir_entry *de;
int res, i;
/* remove the shortname */
offset = sinfo->shortname_offset;
- res = fat_get_entry(dir, &offset, bh, &de);
- if (res < 0) return res;
- if (is_dir) {
- res = vfat_rmdir_free_ino(dir,*bh,de,dentry);
- } else {
- res = vfat_unlink_free_ino(dir,*bh,de,dentry,nospc);
- }
+ res = fat_get_entry(dir, &offset, &bh, &de);
if (res < 0) return res;
-
+ vfat_free_ino(dir,bh,de,victim);
/* remove the longname */
offset = sinfo->longname_offset;
for (i = sinfo->long_slots; i > 0; --i) {
- res = fat_get_entry(dir, &offset, bh, &de);
+ res = fat_get_entry(dir, &offset, &bh, &de);
if (res < 0) {
continue;
}
de->name[0] = DELETED_FLAG;
de->attr = 0;
- fat_mark_buffer_dirty(sb, *bh, 1);
+ fat_mark_buffer_dirty(sb, bh, 1);
}
+ if (bh) fat_brelse(sb, bh);
return 0;
}
-/* Replace inodes in alias dentries and drop all but the initial dentry */
-static void drop_replace_inodes(struct dentry *dentry, struct inode *inode)
+/* Drop all aliases */
+static void drop_aliases(struct dentry *dentry)
{
struct list_head *head, *next, *tmp;
struct dentry *alias;
@@ -1507,12 +1416,6 @@
if (alias == dentry)
continue;
- if (inode) {
- list_del(&alias->d_alias);
- iput(alias->d_inode);
- d_instantiate(alias, inode);
- inode->i_count++;
- }
d_drop(alias);
}
}
@@ -1520,22 +1423,30 @@
static int vfat_rmdirx(struct inode *dir,struct dentry* dentry)
{
- struct super_block *sb = dir->i_sb;
int res;
- struct buffer_head *bh;
struct vfat_slot_info sinfo;
PRINTK1(("vfat_rmdirx: dentry=%p\n", dentry));
- res = vfat_find(dir,&dentry->d_name,1,0,0,&sinfo);
+ res = vfat_find(dir,&dentry->d_name,0,0,&sinfo);
if (res >= 0 && sinfo.total_slots > 0) {
- bh = NULL;
- res = vfat_remove_entry(dir,&sinfo,&bh,dentry,1,0);
- if (res > 0) {
+ if (!list_empty(&dentry->d_hash))
+ return -EBUSY;
+ /* Take care of aliases */
+ if (dentry->d_inode->i_count > 1) {
+ shrink_dcache_parent(dentry->d_parent);
+ if (dentry->d_inode->i_count > 1)
+ return -EBUSY;
+ }
+ res = vfat_empty(dentry->d_inode);
+ if (res)
+ return res;
+
+ res = vfat_remove_entry(dir,&sinfo,dentry->d_inode);
+ if (res >= 0) {
+ dir->i_nlink--;
res = 0;
}
- dir->i_version = ++event;
- if (bh) fat_brelse(sb, bh);
}
return res;
}
@@ -1549,10 +1460,7 @@
res = -EBUSY;
if (list_empty(&dentry->d_hash)) {
res = vfat_rmdirx(dir, dentry);
- if (res >= 0) {
- drop_replace_inodes(dentry, NULL);
- d_delete(dentry);
- }
+ /* If that went OK all aliases are already dropped */
}
return res;
}
@@ -1562,23 +1470,22 @@
struct dentry* dentry,
int nospc) /* Flag special file ? */
{
- struct super_block *sb = dir->i_sb;
int res;
- struct buffer_head *bh;
struct vfat_slot_info sinfo;
PRINTK1(("vfat_unlinkx: dentry=%p, inode=%p\n", dentry, dentry->d_inode));
- bh = NULL;
- res = vfat_find(dir,&dentry->d_name,1,0,0,&sinfo);
+ res = vfat_find(dir,&dentry->d_name,0,0,&sinfo);
if (res >= 0 && sinfo.total_slots > 0) {
- res = vfat_remove_entry(dir,&sinfo,&bh,dentry,0,nospc);
+ if (!S_ISREG(dentry->d_inode->i_mode) && nospc) {
+ return -EPERM;
+ }
+ res = vfat_remove_entry(dir,&sinfo,dentry->d_inode);
if (res > 0) {
res = 0;
}
}
- if (bh) fat_brelse(sb, bh);
return res;
}
@@ -1586,6 +1493,7 @@
int vfat_mkdir(struct inode *dir,struct dentry* dentry,int mode)
{
struct inode *inode;
+ struct vfat_slot_info sinfo;
int res;
PRINTK1(("vfat_mkdir: dentry=%p, inode=%p\n", dentry, dentry->d_inode));
@@ -1597,17 +1505,28 @@
dir->i_nlink++;
inode->i_nlink = 2; /* no need to mark them dirty */
- MSDOS_I(inode)->i_busy = 1; /* prevent lookups */
res = vfat_create_dotdirs(inode, dir);
+ if (res < 0)
+ goto mkdir_failed;
fat_unlock_creation();
- MSDOS_I(inode)->i_busy = 0;
dentry->d_time = dentry->d_parent->d_inode->i_version;
d_instantiate(dentry,inode);
- if (res < 0) {
- if (vfat_rmdir(dir,dentry) < 0)
- fat_fs_panic(dir->i_sb,"rmdir in mkdir failed");
- }
+ return res;
+
+mkdir_failed:
+ fat_unlock_creation();
+ if (vfat_find(dir,&dentry->d_name,0,0,&sinfo) < 0)
+ goto mkdir_panic;
+ if (vfat_remove_entry(dir, &sinfo, inode) < 0)
+ goto mkdir_panic;
+ iput(inode);
+ dir->i_nlink--;
+ return res;
+
+mkdir_panic:
+ dir->i_version = ++event;
+ fat_fs_panic(dir->i_sb,"rmdir in mkdir failed");
return res;
}
@@ -1619,7 +1538,7 @@
PRINTK1(("vfat_unlink: dentry=%p, inode=%p\n", dentry, dentry->d_inode));
res = vfat_unlinkx (dir,dentry,1);
if (res >= 0) {
- drop_replace_inodes(dentry, NULL);
+ drop_aliases(dentry);
d_delete(dentry);
}
return res;
@@ -1640,7 +1559,7 @@
{
struct super_block *sb = old_dir->i_sb;
struct buffer_head *old_bh,*new_bh,*dotdot_bh;
- struct msdos_dir_entry *old_de,*new_de,*dotdot_de;
+ struct msdos_dir_entry *old_de,*dotdot_de;
loff_t old_offset,new_offset,old_longname_offset;
int old_slots,old_ino,new_ino,dotdot_ino;
struct inode *old_inode, *new_inode, *dotdot_inode;
@@ -1648,21 +1567,23 @@
int res, is_dir, i;
int locked = 0;
struct vfat_slot_info sinfo;
- int put_new_inode = 0;
PRINTK1(("vfat_rename: Entering: old_dentry=%p, old_inode=%p, old ino=%ld, new_dentry=%p, new_inode=%p, new ino=%ld\n",
old_dentry, old_dentry->d_inode, old_dentry->d_inode->i_ino,
new_dentry, new_dentry->d_inode,
new_dentry->d_inode ? new_dentry->d_inode->i_ino : 0));
- if (old_dir == new_dir &&
- old_dentry->d_name.len == new_dentry->d_name.len &&
- strncmp(old_dentry->d_name.name, new_dentry->d_name.name,
- old_dentry->d_name.len) == 0)
+ /*
+ * POSIX is braindead (surprise, surprise). It requires that rename()
+ * should return 0 and do nothing if the target has the same inode as
+ * the source. Somebody, get a time machine, return to '89 and tell
+ * RMS & Co *not* to do that idiocy, FAST!
+ */
+ if (old_dentry->d_inode == new_dentry->d_inode)
return 0;
old_bh = new_bh = NULL;
old_inode = new_inode = NULL;
- res = vfat_find(old_dir,&old_dentry->d_name,1,0,0,&sinfo);
+ res = vfat_find(old_dir,&old_dentry->d_name,0,0,&sinfo);
PRINTK3(("vfat_rename 2\n"));
if (res < 0) goto rename_done;
@@ -1677,57 +1598,79 @@
res = -ENOENT;
old_inode = old_dentry->d_inode;
is_dir = S_ISDIR(old_inode->i_mode);
+
+ /*
+ * Race: we can be hit by another rename after this check.
+ * For the time being use fat_lock_creation(), but it's
+ * ugly. FIXME.
+ */
+
+ fat_lock_creation(); locked = 1;
+
if (is_dir) {
- if ((old_dir->i_dev != new_dir->i_dev) ||
- (old_ino == new_dir->i_ino)) {
+ /* We can't use d_subdir() here. Arrgh. */
+ for (walk=new_dentry;walk!=walk->d_parent;walk=walk->d_parent) {
+ if (walk->d_inode != old_dentry->d_inode)
+ continue;
res = -EINVAL;
goto rename_done;
}
- walk = new_dentry;
- /* prevent moving directory below itself */
- for (;;) {
- if (walk == old_dentry) return -EINVAL;
- if (walk == walk->d_parent) break;
- walk = walk->d_parent;
- }
}
- res = vfat_find(new_dir,&new_dentry->d_name,1,0,is_dir,&sinfo);
-
- PRINTK3(("vfat_rename 4\n"));
- if (res > -1) {
- int new_is_dir;
-
- PRINTK3(("vfat_rename 5\n"));
- /* Filename currently exists. Need to delete it */
- new_offset = sinfo.shortname_offset;
- res = fat_get_entry(new_dir, &new_offset, &new_bh, &new_de);
- PRINTK3(("vfat_rename 6\n"));
- if (res < 0) goto rename_done;
+ if (new_dentry->d_inode) {
+ /*
+ * OK, we have to remove the target. We should do it so
+ * that nobody might go and find it negative. Actually we
+ * should give warranties wrt preserving target over the
+ * possible crash, but that's another story. We can't
+ * get here with the target unhashed, so the directory entry
+ * must exist.
+ */
- if (!(new_inode = iget(new_dir->i_sb,res)))
+ new_inode = new_dentry->d_inode;
+ res = vfat_find(new_dir,&new_dentry->d_name,0,is_dir,&sinfo);
+ if (res < 0 || new_inode->i_ino != sinfo.ino) {
+ /* WTF??? Cry and fail. */
+ printk(KERN_WARNING "vfat_rename: fs corrupted\n");
goto rename_done;
- new_is_dir = S_ISDIR(new_inode->i_mode);
- iput(new_inode);
- if (new_is_dir) {
- PRINTK3(("vfat_rename 7\n"));
- res = vfat_rmdirx(new_dir,new_dentry);
- PRINTK3(("vfat_rename 8\n"));
- if (res < 0) goto rename_done;
- } else {
- /* Is this the same file, different case? */
- if (new_inode != old_inode) {
- PRINTK3(("vfat_rename 9\n"));
- res = vfat_unlink(new_dir,new_dentry);
- PRINTK3(("vfat_rename 10\n"));
- if (res < 0) goto rename_done;
+ }
+
+ if (is_dir) {
+ /*
+ * Target is a directory. No other owners will
+ * be tolerated.
+ */
+ res = -EBUSY;
+ if (!d_try_drop(new_dentry))
+ goto rename_done;
+ /*
+ * OK, let's try to get rid of other dentries.
+ * No need to do it if i_count is 1.
+ */
+ if (new_inode->i_count>1) {
+ shrink_dcache_parent(new_dentry->d_parent);
+ if (new_inode->i_count>1)
+ goto rename_done;
}
+ res = vfat_empty(new_inode);
+ if (res)
+ goto rename_done;
+ res = vfat_remove_entry(new_dir,&sinfo,new_inode);
+ if (res)
+ goto rename_done;
+ new_dir->i_nlink--;
+ d_delete(new_dentry);
+ } else {
+ /* Plain d_drop() is safe here. */
+ d_drop(new_dentry);
+ res = vfat_unlink(new_dir,new_dentry);
+ if (res)
+ goto rename_done;
}
}
PRINTK3(("vfat_rename 11\n"));
- fat_lock_creation(); locked = 1;
- res = vfat_find(new_dir,&new_dentry->d_name,1,1,is_dir,&sinfo);
+ res = vfat_find(new_dir,&new_dentry->d_name,1,is_dir,&sinfo);
PRINTK3(("vfat_rename 12\n"));
if (res < 0) goto rename_done;
@@ -1736,31 +1679,18 @@
new_ino = sinfo.ino;
PRINTK3(("vfat_rename 13: new_ino=%d\n", new_ino));
- if (!(new_inode = iget(new_dir->i_sb,new_ino))) goto rename_done;
- put_new_inode = 1;
-
- new_inode->i_mode = old_inode->i_mode;
- new_inode->i_size = old_inode->i_size;
- new_inode->i_blocks = old_inode->i_blocks;
- new_inode->i_mtime = old_inode->i_mtime;
- new_inode->i_atime = old_inode->i_atime;
- new_inode->i_ctime = old_inode->i_ctime;
- new_inode->i_nlink = old_inode->i_nlink;
- new_inode->i_op = old_inode->i_op;
- MSDOS_I(new_inode)->i_ctime_ms = MSDOS_I(old_inode)->i_ctime_ms;
-
- MSDOS_I(new_inode)->i_start = MSDOS_I(old_inode)->i_start;
- MSDOS_I(new_inode)->i_logstart = MSDOS_I(old_inode)->i_logstart;
- MSDOS_I(new_inode)->i_attrs = MSDOS_I(old_inode)->i_attrs;
+ /* XXX: take care of other owners */
+ remove_inode_hash(old_inode);
fat_cache_inval_inode(old_inode);
- mark_inode_dirty(new_inode);
+ old_inode->i_ino = new_ino;
+ old_inode->i_version = ++event;
+ insert_inode_hash(old_inode);
+ mark_inode_dirty(old_inode);
old_dir->i_version = ++event;
new_dir->i_version = ++event;
- PRINTK3(("vfat_rename 14: old_slots=%d\n",old_slots));
-
/* remove the old entry */
for (i = old_slots; i > 0; --i) {
res = fat_get_entry(old_dir, &old_longname_offset, &old_bh, &old_de);
@@ -1772,7 +1702,6 @@
old_de->attr = 0;
fat_mark_buffer_dirty(sb, old_bh, 1);
}
- PRINTK3(("vfat_rename 15b\n"));
if (S_ISDIR(old_inode->i_mode)) {
if ((res = fat_scan(old_inode,MSDOS_DOTDOT,&dotdot_bh,
@@ -1796,26 +1725,9 @@
fat_brelse(sb, dotdot_bh);
}
- /*
- * This convinces the VFS layer to drop the old inode,
- * but at the same time fools the VFAT layer to not
- * actually delete any of the blocks in the old file
- * (because they are very much used by the renamed file)
- */
- MSDOS_I(old_inode)->i_start = 0;
- MSDOS_I(old_inode)->i_logstart = 0;
- old_inode->i_nlink = 0;
-
- if (res > 0) res = 0;
-
- if (res == 0) {
- drop_replace_inodes(old_dentry, new_inode);
- list_del(&old_dentry->d_alias);
- iput(old_dentry->d_inode);
- d_instantiate(old_dentry, new_inode);
-
+ if (res >= 0) {
d_move(old_dentry, new_dentry);
- put_new_inode = 0;
+ res = 0;
}
rename_done:
@@ -1825,9 +1737,8 @@
fat_brelse(sb, old_bh);
if (new_bh)
fat_brelse(sb, new_bh);
- if (put_new_inode)
- iput(new_inode);
return res;
+
}
-
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