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authorRalf Baechle <ralf@linux-mips.org>1997-07-20 14:56:40 +0000
committerRalf Baechle <ralf@linux-mips.org>1997-07-20 14:56:40 +0000
commite308faf24f68e262d92d294a01ddca7a17e76762 (patch)
tree22c47cb315811834861f013067878ff664e95abd /fs/namei.c
parent30c6397ce63178fcb3e7963ac247f0a03132aca9 (diff)
Sync with Linux 2.1.46.
Diffstat (limited to 'fs/namei.c')
-rw-r--r--fs/namei.c1615
1 files changed, 638 insertions, 977 deletions
diff --git a/fs/namei.c b/fs/namei.c
index 198179b98..2ec173f0d 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -12,7 +12,6 @@
* lookup logic.
*/
-#include <linux/config.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
@@ -20,10 +19,7 @@
#include <linux/fcntl.h>
#include <linux/stat.h>
#include <linux/mm.h>
-#include <linux/dalloc.h>
-#include <linux/nametrans.h>
#include <linux/proc_fs.h>
-#include <linux/omirr.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
@@ -37,10 +33,6 @@
#undef DEBUG /* some other debugging */
-/* local flags for __namei() */
-#define NAM_SEMLOCK 8 /* set a semlock on the last dir */
-#define NAM_TRANSCREATE 16 /* last component may be created, try "=CREATE#" suffix*/
-#define NAM_NO_TRAILSLASH 32 /* disallow trailing slashes by returning EISDIR */
#define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE])
/* [Feb-1997 T. Schoebel-Theuer]
@@ -56,7 +48,7 @@
* is done solely in the VFS level, such that <fs>_follow_link() is not
* used any more and could be removed in future. As a side effect,
* dir_namei(), _namei() and follow_link() are now replaced with a single
- * function __namei() that can handle all the special cases of the former
+ * function lookup_dentry() that can handle all the special cases of the former
* code.
*
* With the new dcache, the pathname is stored at each inode, at least as
@@ -95,13 +87,13 @@ static inline char * get_page(void)
char * res;
down(&quicklock);
res = quicklist;
- if(res) {
+ if (res) {
#ifdef DEBUG
char * tmp = res;
int i;
for(i=0; i<quickcount; i++)
tmp = *(char**)tmp;
- if(tmp)
+ if (tmp)
printk("bad quicklist %x\n", (int)tmp);
#endif
quicklist = *(char**)res;
@@ -113,9 +105,21 @@ static inline char * get_page(void)
return res;
}
+/*
+ * Kernel pointers have redundant information, so we can use a
+ * scheme where we can return either an error code or a dentry
+ * pointer with the same return value.
+ *
+ * This should be a per-architecture thing, to allow different
+ * error and pointer decisions.
+ */
+#define ERR_PTR(err) ((void *)((long)(err)))
+#define PTR_ERR(ptr) ((long)(ptr))
+#define IS_ERR(ptr) ((unsigned long)(ptr) > (unsigned long)(-1000))
+
inline void putname(char * name)
{
- if(name) {
+ if (name) {
down(&quicklock);
*(char**)name = quicklist;
quicklist = name;
@@ -154,20 +158,22 @@ static inline int do_getname(const char *filename, char *page)
return retval;
}
-int getname(const char * filename, char **result)
+char * getname(const char * filename)
{
- char *tmp;
- int retval;
+ char *tmp, *result;
+ result = ERR_PTR(-ENOMEM);
tmp = get_page();
- if(!tmp)
- return -ENOMEM;
- retval = do_getname(filename, tmp);
- if (retval < 0)
- putname(tmp);
- else
- *result = tmp;
- return retval;
+ if (tmp) {
+ int retval = do_getname(filename, tmp);
+
+ result = tmp;
+ if (retval < 0) {
+ putname(tmp);
+ result = ERR_PTR(retval);
+ }
+ }
+ return result;
}
/*
@@ -222,417 +228,207 @@ void put_write_access(struct inode * inode)
inode->i_writecount--;
}
-static /*inline */ int concat(struct qstr * name, struct qstr * appendix, char * buf)
+/*
+ * This is called when everything else fails, and we actually have
+ * to go to the low-level filesystem to find out what we should do..
+ *
+ * We get the directory semaphore, and after getting that we also
+ * make sure that nobody added the entry to the dcache in the meantime..
+ */
+static struct dentry * real_lookup(struct dentry * parent, struct qstr * name)
{
- int totallen = name->len;
- if(name->len > MAX_TRANS_FILELEN ||
- appendix->len > MAX_TRANS_SUFFIX) {
- return -ENAMETOOLONG;
+ struct dentry * result;
+ struct inode *dir = parent->d_inode;
+
+ result = ERR_PTR(-ENOTDIR);
+ if (dir->i_op && dir->i_op->lookup) {
+ down(&dir->i_sem);
+ result = d_lookup(parent, name);
+ if (!result) {
+ int error;
+ result = d_alloc(parent, name);
+ error = dir->i_op->lookup(dir, result);
+ if (error) {
+ d_free(result);
+ result = ERR_PTR(error);
+ }
+ }
+ up(&dir->i_sem);
}
- memcpy(buf, name->name, name->len);
- memcpy(buf + name->len, appendix->name, appendix->len);
- totallen += appendix->len;
- buf[totallen] = '\0';
- return totallen;
+ return result;
}
-/* Internal lookup() using the new generic dcache.
- * buf must only be supplied if appendix!=NULL.
- */
-static int cached_lookup(struct inode * dir, struct qstr * name,
- struct qstr * appendix, char * buf,
- struct qstr * res_name, struct dentry ** res_entry,
- struct inode ** result)
+/* Internal lookup() using the new generic dcache. */
+static struct dentry * cached_lookup(struct dentry * parent, struct qstr * name)
{
- struct qstr tmp = { name->name, name->len };
- int error;
- struct dentry * cached;
-
- *result = NULL;
- if(name->len >= D_MAXLEN)
- return -ENAMETOOLONG;
- vfs_lock();
- cached = d_lookup(dir, name, appendix);
- if(cached) {
- struct inode *inode = NULL;
+ struct dentry * dentry = d_lookup(parent, name);
- if(cached->u.d_inode && (inode = d_inode(&cached))) {
- error = 0;
- if(appendix && res_name) {
- tmp.len = error = concat(name, appendix, buf);
- tmp.name = buf;
- if(error > 0)
- error = 0;
- }
- } else {
- error = -ENOENT;
+ if (dentry) {
+ if (dentry->d_revalidate) {
+ /* spin_unlock(&dentry_lock); */
+ dentry = dentry->d_revalidate(dentry);
+ /* spin_lock(&dentry_lock); */
}
- vfs_unlock();
- if(res_entry)
- *res_entry = cached;
- /* Since we are bypassing the iget() mechanism, we have to
- * fabricate the act of crossing any mount points.
+ /*
+ * The parent d_count _should_ be at least 2: one for the
+ * dentry we found, and one for the fact that we are using
+ * it.
*/
- if(!error && inode && inode->i_mount) {
- do {
- struct inode *mnti = inode->i_mount;
- iinc(mnti);
- iput(inode);
- inode = mnti;
- } while(inode->i_mount);
+ if (parent->d_count <= 1) {
+ printk("lookup of %s success in %s, but parent count is %d\n",
+ dentry->d_name.name, parent->d_name.name, parent->d_count);
}
- *result = inode;
- goto done;
- } else
- vfs_unlock();
-
- if(appendix) {
- tmp.len = error = concat(name, appendix, buf);
- tmp.name = buf;
- if(error < 0)
- goto done;
- }
- atomic_inc(&dir->i_count);
- error = dir->i_op->lookup(dir, tmp.name, tmp.len, result);
- if(dir->i_dentry && tmp.len &&
- (!error || (error == -ENOENT && (!dir->i_sb || !dir->i_sb->s_type ||
- !(dir->i_sb->s_type->fs_flags & FS_NO_DCACHE))))) {
- struct dentry * res;
- vfs_lock();
- res = d_entry(dir->i_dentry, &tmp, error ? NULL : *result);
- vfs_unlock();
- if(res_entry)
- *res_entry = res;
}
-done:
- if(res_name) {
- if(error) {
- res_name->name = name->name;
- res_name->len = name->len;
- } else {
- res_name->name = tmp.name;
- res_name->len = tmp.len;
- }
- }
- return error;
+ return dentry;
}
-#ifdef CONFIG_TRANS_NAMES
-/* If a normal filename is seen, try to determine whether a
- * "#keyword=context#" file exists and return the new filename.
- * If the name is to be created (create_mode), check whether a
- * "#keyword=CREATE" name exists and optionally return the corresponding
- * context name even if it didn't exist before.
+/*
+ * "." and ".." are special - ".." especially so because it has to be able
+ * to know about the current root directory and parent relationships
*/
-static int check_suffixes(struct inode * dir, struct qstr * name,
- int create_mode, char * buf,
- struct qstr * res_name, struct dentry ** res_entry,
- struct inode ** result)
+static struct dentry * reserved_lookup(struct dentry * parent, struct qstr * name)
{
- struct translations * trans;
- char * env;
- struct qstr * suffixes;
- int i;
- int error = -ENOENT;
-
- if(!buf)
- panic("buf==NULL");
- env = env_transl();
-#ifdef CONFIG_TRANS_RESTRICT
- if(!env && dir->i_gid != CONFIG_TRANS_GID) {
- return error;
- }
-#endif
- trans = get_translations(env);
- suffixes = create_mode ? trans->c_name : trans->name;
- for(i = 0; i < trans->count; i++) {
- error = cached_lookup(dir, name, &suffixes[i],
- buf, res_name, res_entry, result);
- if(!error) {
- if(res_name && create_mode) {
- /* buf == res_name->name, but is writable */
- memcpy(buf + name->len,
- trans->name[i].name,
- trans->name[i].len);
- res_name->len = name->len + trans->name[i].len;
- buf[res_name->len] = '\0';
- }
+ struct dentry *result = NULL;
+ if (name->name[0] == '.') {
+ switch (name->len) {
+ default:
break;
+ case 2:
+ if (name->name[1] != '.')
+ break;
+
+ if (parent != current->fs->root)
+ parent = parent->d_covers->d_parent;
+ /* fallthrough */
+ case 1:
+ result = parent;
}
}
- if(env)
- free_page((unsigned long)trans);
- return error;
-}
-
-#endif
-
-/* Any operations involving reserved names at the VFS level should go here. */
-static /*inline*/ int reserved_lookup(struct inode * dir, struct qstr * name,
- int create_mode, char * buf,
- struct inode ** result)
-{
- int error = -ENOENT;
- if(name->name[0] == '.') {
- if(name->len == 1) {
- *result = dir;
- error = 0;
- } else if (name->len==2 && name->name[1] == '.') {
- if (dir == current->fs->root) {
- *result = dir;
- error = 0;
- }
- else if(dir->i_dentry) {
- error = 0;
- *result = dir->i_dentry->d_parent->u.d_inode;
- if(!*result) {
- printk("dcache parent directory is lost");
- error = -ESTALE; /* random error */
- }
- }
- }
- if(!error)
- atomic_inc(&(*result)->i_count);
- }
- return error;
+ return result;
}
/* In difference to the former version, lookup() no longer eats the dir. */
-static /*inline*/ int lookup(struct inode * dir, struct qstr * name, int create_mode,
- char * buf, struct qstr * res_name,
- struct dentry ** res_entry, struct inode ** result)
+static struct dentry * lookup(struct dentry * dir, struct qstr * name)
{
- int perm;
-
- *result = NULL;
- perm = -ENOENT;
- if (!dir)
- goto done;
+ int err;
+ struct dentry * result;
/* Check permissions before traversing mount-points. */
- perm = permission(dir,MAY_EXEC);
- if (perm)
- goto done;
- perm = reserved_lookup(dir, name, create_mode, buf, result);
- if(!perm) {
- if(res_name) {
- res_name->name = name->name;
- res_name->len = name->len;
- }
- goto done;
- }
- perm = -ENOTDIR;
- if (!dir->i_op || !dir->i_op->lookup)
- goto done;
-#ifdef CONFIG_TRANS_NAMES /* try suffixes */
- perm = check_suffixes(dir, name, 0, buf, res_name, res_entry, result);
- if(perm) /* try original name */
-#endif
- perm = cached_lookup(dir, name, NULL, buf, res_name, res_entry, result);
-#ifdef CONFIG_TRANS_NAMES
- if(perm == -ENOENT && create_mode) { /* try the =CREATE# suffix */
- struct inode * dummy;
- if(!check_suffixes(dir, name, 1, buf, res_name, NULL, &dummy)) {
- iput(dummy);
- }
+ err = permission(dir->d_inode, MAY_EXEC);
+ result = ERR_PTR(err);
+ if (err)
+ goto done_error;
+
+ result = reserved_lookup(dir, name);
+ if (result)
+ goto done_noerror;
+
+ result = cached_lookup(dir, name);
+ if (result)
+ goto done_noerror;
+
+ result = real_lookup(dir, name);
+
+ if (!IS_ERR(result)) {
+done_noerror:
+ result = dget(result->d_mounts);
}
-#endif
-done:
- return perm;
+done_error:
+ return result;
}
-/* [8-Feb-97 T. Schoebel-Theuer] follow_link() modified for generic operation
- * on the VFS layer: first call <fs>_readlink() and then open_namei().
- * All <fs>_follow_link() are not used any more and may be eliminated
- * (by Linus; I refrained in order to not break other patches).
- * Single exeption is procfs, where proc_follow_link() is used
- * internally (and perhaps should be rewritten).
- * Note: [partly obsolete] I removed parameters flag and mode, since now
- * __namei() is called instead of open_namei(). In the old semantics,
- * the _last_ instance of open_namei() did the real create() if O_CREAT was
- * set and the name existed already in form of a symlink. This has been
- * simplified now, and also the semantics when combined with O_EXCL has changed.
- ****************************************************************************
- * [13-Feb-97] Complete rewrite -> functionality of reading symlinks factored
- * out into _read_link(). The above notes remain valid in principle.
+/*
+ * This should check "link_count", but doesn't do that yet..
*/
-static /*inline*/ int _read_link(struct inode * inode, char ** linkname, int loopcount)
+static struct dentry * do_follow_link(struct dentry *base, struct dentry *dentry)
{
- unsigned long old_fs;
- int error;
+ struct inode * inode = dentry->d_inode;
- error = -ENOSYS;
- if (!inode->i_op || !inode->i_op->readlink)
- goto done;
- error = -ELOOP;
- if (current->link_count + loopcount > 10)
- goto done;
- error = -ENOMEM;
- if(!*linkname && !(*linkname = get_page()))
- goto done;
- if (DO_UPDATE_ATIME(inode)) {
- inode->i_atime = CURRENT_TIME;
- inode->i_dirt = 1;
- }
- atomic_inc(&inode->i_count);
- old_fs = get_fs();
- set_fs(KERNEL_DS);
- error = inode->i_op->readlink(inode, *linkname, PAGE_SIZE);
- set_fs(old_fs);
- if(!error) {
- error = -ENOENT; /* ? or other error code ? */
- } else if(error > 0) {
- (*linkname)[error] = '\0';
- error = 0;
+ if (inode && inode->i_op && inode->i_op->follow_link) {
+ struct dentry *result;
+
+ /* This eats the base */
+ result = inode->i_op->follow_link(inode, base);
+ base = dentry;
+ dentry = result;
}
-done:
- iput(inode);
- return error;
+ dput(base);
+ return dentry;
}
-/* [13-Feb-97 T. Schoebel-Theuer] complete rewrite:
- * merged dir_name(), _namei() and follow_link() into one new routine
- * that obeys all the special cases hidden in the old routines in a
- * (hopefully) systematic way:
- * parameter retrieve_mode is bitwise or'ed of the ST_* flags.
- * if res_inode is a NULL pointer, dont try to retrieve the last component
- * at all. Parameters with prefix last_ are used only if res_inode is
- * non-NULL and refer to the last component of the path only.
+/*
+ * Name resolution.
+ *
+ * This is the basic name resolution function, turning a pathname
+ * into the final dentry.
*/
-int __namei(int retrieve_mode, const char * name, struct inode * base,
- char * buf, struct inode ** res_dir, struct inode ** res_inode,
- struct qstr * last_name, struct dentry ** last_entry,
- int * last_error)
+struct dentry * lookup_dentry(const char * name, struct dentry * base, int follow_link)
{
- char c;
- struct qstr this;
- char * linkname = NULL;
- char * oldlinkname = NULL;
- int trail_flag = 0;
- int loopcount = 0;
- int error;
-#ifdef DEBUG
- if(last_name) {
- last_name->name = "(Uninitialized)";
- last_name->len = 15;
- }
-#endif
-again:
- error = -ENOENT;
- this.name = name;
- if (this.name[0] == '/') {
- if(base)
- iput(base);
- if (__prefix_namei(retrieve_mode, this.name, base, buf,
- res_dir, res_inode,
- last_name, last_entry, last_error) == 0)
- return 0;
- base = current->fs->root;
- atomic_inc(&base->i_count);
- this.name++;
+ struct dentry * dentry;
+
+ if (*name == '/') {
+ if (base)
+ dput(base);
+ base = dget(current->fs->root);
+ do {
+ name++;
+ } while (*name == '/');
} else if (!base) {
- base = current->fs->pwd;
- atomic_inc(&base->i_count);
+ base = dget(current->fs->pwd);
}
+
+ if (!*name)
+ goto return_base;
+
+ /* At this point we know we have a real path component. */
for(;;) {
- struct inode * inode;
- const char * tmp = this.name;
int len;
+ unsigned long hash;
+ struct qstr this;
+ char c, follow;
- for(len = 0; (c = *tmp++) && (c != '/'); len++) ;
- this.len = len;
- if(!c)
+ dentry = ERR_PTR(-ENOENT);
+ if (!base->d_inode)
break;
- while((c = *tmp) == '/') /* remove embedded/trailing slashes */
- tmp++;
- if(!c) {
- trail_flag = 1;
- if(retrieve_mode & NAM_NO_TRAILSLASH) {
- error = -EISDIR;
- goto alldone;
- }
- break;
- }
-#if 0
- if(atomic_read(&base->i_count) == 0)
- printk("vor lookup this=%s tmp=%s\n", this.name, tmp);
-#endif
- error = lookup(base, &this, 0, buf, NULL, NULL, &inode);
-#if 0
- if(atomic_read(&base->i_count) == 0)
- printk("nach lookup this=%s tmp=%s\n", this.name, tmp);
-#endif
- if (error)
- goto alldone;
- if(S_ISLNK(inode->i_mode)) {
- error = _read_link(inode, &linkname, loopcount);
- if(error)
- goto alldone;
- current->link_count++;
- error = __namei((retrieve_mode &
- ~(NAM_SEMLOCK|NAM_TRANSCREATE|NAM_NO_TRAILSLASH))
- | NAM_FOLLOW_LINK,
- linkname, base, buf,
- &base, &inode, NULL, NULL, NULL);
- current->link_count--;
- if(error)
- goto alldone;
- }
-#if 0
- if(atomic_read(&base->i_count) == 0)
- printk("this=%s tmp=%s\n", this.name, tmp);
-#endif
- this.name = tmp;
- iput(base);
- base = inode;
- }
- if(res_inode) {
- if(retrieve_mode & NAM_SEMLOCK)
- down(&base->i_sem);
- error = lookup(base, &this, retrieve_mode & NAM_TRANSCREATE,
- buf, last_name, last_entry, res_inode);
- if(!error && S_ISLNK((*res_inode)->i_mode) &&
- ((retrieve_mode & NAM_FOLLOW_LINK) ||
- (trail_flag && (retrieve_mode & NAM_FOLLOW_TRAILSLASH)))) {
- char * tmp;
-
- error = _read_link(*res_inode, &linkname, loopcount);
- if(error)
- goto lastdone;
- if(retrieve_mode & NAM_SEMLOCK)
- up(&base->i_sem);
- /* exchange pages */
- name = tmp = linkname;
- linkname = oldlinkname; oldlinkname = tmp;
- loopcount++;
- goto again; /* Tail recursion elimination "by hand",
- * uses less dynamic memory.
- */
-
- /* Note that trail_flag is not reset, so it
- * does not matter in a symlink chain where a
- * trailing slash indicates a directory endpoint.
- */
- }
- if(!error && trail_flag && !S_ISDIR((*res_inode)->i_mode)) {
- iput(*res_inode);
- error = -ENOTDIR;
- }
- lastdone:
- if(last_error) {
- *last_error = error;
- error = 0;
+ this.name = name;
+ hash = init_name_hash();
+ len = 0;
+ c = *name;
+ do {
+ len++; name++;
+ hash = partial_name_hash(c, hash);
+ c = *name;
+ } while (c && (c != '/'));
+
+ this.len = len;
+ this.hash = end_name_hash(hash);
+
+ /* remove trailing slashes? */
+ follow = follow_link;
+ if (c) {
+ follow |= c;
+ do {
+ c = *++name;
+ } while (c == '/');
}
+
+ dentry = lookup(base, &this);
+ if (IS_ERR(dentry))
+ break;
+
+ if (!follow)
+ break;
+
+ base = do_follow_link(base, dentry);
+ if (c && !IS_ERR(base))
+ continue;
+
+return_base:
+ return base;
}
-alldone:
- if(!error && res_dir)
- *res_dir = base;
- else
- iput(base);
- putname(linkname);
- putname(oldlinkname);
- return error;
+ dput(base);
+ return dentry;
}
/*
@@ -641,24 +437,41 @@ alldone:
* is used by most simple commands to get the inode of a specified name.
* Open, link etc use their own routines, but this is enough for things
* like 'chmod' etc.
+ *
+ * namei exists in two versions: namei/lnamei. The only difference is
+ * that namei follows links, while lnamei does not.
*/
+struct dentry * __namei(const char *pathname, int follow_link)
+{
+ char *name;
+ struct dentry *dentry;
+
+ name = getname(pathname);
+ dentry = (struct dentry *) name;
+ if (!IS_ERR(name)) {
+ dentry = lookup_dentry(name, NULL, follow_link);
+ putname(name);
+ if (!IS_ERR(dentry)) {
+ if (!dentry->d_inode) {
+ dput(dentry);
+ dentry = ERR_PTR(-ENOENT);
+ }
+ }
+ }
+ return dentry;
+}
-/* [Feb 1997 T.Schoebel-Theuer] lnamei() completely removed; can be
- * simulated when calling with retrieve_mode==NAM_FOLLOW_TRAILSLASH.
- */
-int namei(int retrieve_mode, const char *pathname, struct inode **res_inode)
+static inline struct inode *get_parent(struct dentry *dentry)
{
- int error;
- char * tmp;
+ return dentry->d_parent->d_inode;
+}
- error = getname(pathname, &tmp);
- if (!error) {
- char buf[MAX_TRANS_FILELEN+MAX_TRANS_SUFFIX+2];
- error = __namei(retrieve_mode, tmp, NULL,
- buf, NULL, res_inode, NULL, NULL, NULL);
- putname(tmp);
- }
- return error;
+static inline struct inode *lock_parent(struct dentry *dentry)
+{
+ struct inode *dir = dentry->d_parent->d_inode;
+
+ down(&dir->i_sem);
+ return dir;
}
/*
@@ -674,175 +487,157 @@ int namei(int retrieve_mode, const char *pathname, struct inode **res_inode)
* which is a lot more logical, and also allows the "no perm" needed
* for symlinks (where the permissions are checked later).
*/
-int open_namei(const char * pathname, int flag, int mode,
- struct inode ** res_inode, struct inode * base)
+struct dentry * open_namei(const char * pathname, int flag, int mode)
{
- char buf[MAX_TRANS_FILELEN+MAX_TRANS_SUFFIX+2];
- struct qstr last;
- int error;
- int lasterror;
- struct inode * dir, * inode;
- int namei_mode;
+ int acc_mode, error;
+ struct inode *inode;
+ struct dentry *dentry;
mode &= S_IALLUGO & ~current->fs->umask;
mode |= S_IFREG;
- namei_mode = NAM_FOLLOW_LINK;
- if(flag & O_CREAT)
- namei_mode |= NAM_SEMLOCK|NAM_TRANSCREATE|NAM_NO_TRAILSLASH;
- error = __namei(namei_mode, pathname, base, buf,
- &dir, &inode, &last, NULL, &lasterror);
- if (error)
- goto exit;
- error = lasterror;
+ dentry = lookup_dentry(pathname, NULL, 1);
+ if (IS_ERR(dentry))
+ return dentry;
+
+ acc_mode = ACC_MODE(flag);
if (flag & O_CREAT) {
- if (!error) {
- if (flag & O_EXCL) {
+ struct inode *dir;
+
+ dir = lock_parent(dentry);
+ /*
+ * The existence test must be done _after_ getting the directory
+ * semaphore - the dentry might otherwise change.
+ */
+ if (dentry->d_inode) {
+ error = 0;
+ if (flag & O_EXCL)
error = -EEXIST;
- }
} else if (IS_RDONLY(dir))
error = -EROFS;
else if (!dir->i_op || !dir->i_op->create)
error = -EACCES;
- else if ((error = permission(dir,MAY_WRITE | MAY_EXEC)) != 0)
- ; /* error is already set! */
- else {
- d_del(d_lookup(dir, &last, NULL), D_REMOVE);
- atomic_inc(&dir->i_count); /* create eats the dir */
+ else if ((error = permission(dir,MAY_WRITE | MAY_EXEC)) == 0) {
if (dir->i_sb && dir->i_sb->dq_op)
dir->i_sb->dq_op->initialize(dir, -1);
- error = dir->i_op->create(dir, last.name, last.len,
- mode, res_inode);
-#ifdef CONFIG_OMIRR
- if(!error)
- omirr_print(dir->i_dentry, NULL, &last,
- " c %ld %d ", CURRENT_TIME, mode);
-#endif
- up(&dir->i_sem);
- goto exit_dir;
+ error = dir->i_op->create(dir, dentry, mode);
+ /* Don't check for write permission */
+ acc_mode = 0;
}
up(&dir->i_sem);
+ if (error)
+ goto exit;
}
+
+ error = -ENOENT;
+ inode = dentry->d_inode;
+ if (!inode)
+ goto exit;
+
+ error = -EISDIR;
+ if (S_ISDIR(inode->i_mode) && (flag & FMODE_WRITE))
+ goto exit;
+
+ error = permission(inode,acc_mode);
if (error)
- goto exit_inode;
+ goto exit;
- if (S_ISDIR(inode->i_mode) && (flag & 2)) {
- error = -EISDIR;
- goto exit_inode;
- }
- if ((error = permission(inode,ACC_MODE(flag))) != 0) {
- goto exit_inode;
- }
+ /*
+ * FIFO's, sockets and device files are special: they don't
+ * actually live on the filesystem itself, and as such you
+ * can write to them even if the filesystem is read-only.
+ */
if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
- /*
- * 2-Feb-1995 Bruce Perens <Bruce@Pixar.com>
- * Allow opens of Unix domain sockets and FIFOs for write on
- * read-only filesystems. Their data does not live on the disk.
- *
- * If there was something like IS_NODEV(inode) for
- * pipes and/or sockets I'd check it here.
- */
flag &= ~O_TRUNC;
- }
- else if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) {
- if (IS_NODEV(inode)) {
- error = -EACCES;
- goto exit_inode;
- }
+ } else if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) {
+ error = -EACCES;
+ if (IS_NODEV(inode))
+ goto exit;
+
flag &= ~O_TRUNC;
} else {
- if (IS_RDONLY(inode) && (flag & 2)) {
- error = -EROFS;
- goto exit_inode;
- }
+ error = -EROFS;
+ if (IS_RDONLY(inode) && (flag & 2))
+ goto exit;
}
/*
* An append-only file must be opened in append mode for writing.
*/
- if (IS_APPEND(inode) && ((flag & FMODE_WRITE) && !(flag & O_APPEND))) {
- error = -EPERM;
- goto exit_inode;
- }
+ error = -EPERM;
+ if (IS_APPEND(inode) && ((flag & FMODE_WRITE) && !(flag & O_APPEND)))
+ goto exit;
+
if (flag & O_TRUNC) {
- if ((error = get_write_access(inode)))
- goto exit_inode;
+ error = get_write_access(inode);
+ if (error)
+ goto exit;
+
/*
* Refuse to truncate files with mandatory locks held on them.
*/
error = locks_verify_locked(inode);
- if (error)
- goto exit_inode;
- if (inode->i_sb && inode->i_sb->dq_op)
- inode->i_sb->dq_op->initialize(inode, -1);
+ if (!error) {
+ if (inode->i_sb && inode->i_sb->dq_op)
+ inode->i_sb->dq_op->initialize(inode, -1);
- error = do_truncate(inode, 0);
+ error = do_truncate(inode, 0);
+ }
put_write_access(inode);
+ if (error)
+ goto exit;
} else
if (flag & FMODE_WRITE)
if (inode->i_sb && inode->i_sb->dq_op)
inode->i_sb->dq_op->initialize(inode, -1);
-exit_inode:
- if(error) {
- if(!lasterror)
- iput(inode);
- } else
- *res_inode = inode;
-exit_dir:
- iput(dir);
+
+ return dentry;
+
exit:
- return error;
+ dput(dentry);
+ return ERR_PTR(error);
}
-int do_mknod(const char * filename, int mode, dev_t dev)
+struct dentry * do_mknod(const char * filename, int mode, dev_t dev)
{
- char buf[MAX_TRANS_FILELEN+MAX_TRANS_SUFFIX+2];
- struct qstr last;
- int error, lasterror;
- struct inode * dir;
- struct inode * inode;
+ int error;
+ struct inode *dir;
+ struct dentry *dentry, *retval;
mode &= ~current->fs->umask;
- error = __namei(NAM_FOLLOW_LINK|NAM_TRANSCREATE|NAM_NO_TRAILSLASH,
- filename, NULL, buf,
- &dir, &inode, &last, NULL, &lasterror);
+ dentry = lookup_dentry(filename, NULL, 1);
+ if (IS_ERR(dentry))
+ return dentry;
+
+ dir = lock_parent(dentry);
+
+ retval = ERR_PTR(-EEXIST);
+ if (dentry->d_inode)
+ goto exit_lock;
+
+ retval = ERR_PTR(-EROFS);
+ if (IS_RDONLY(dir))
+ goto exit_lock;
+
+ error = permission(dir,MAY_WRITE | MAY_EXEC);
+ retval = ERR_PTR(error);
if (error)
- goto exit;
- if(!lasterror) {
- error = -EEXIST;
- goto exit_inode;
- }
- if (!last.len) {
- error = -ENOENT;
- goto exit_inode;
- }
- if (IS_RDONLY(dir)) {
- error = -EROFS;
- goto exit_inode;
- }
- if ((error = permission(dir,MAY_WRITE | MAY_EXEC)) != 0)
- goto exit_inode;
- if (!dir->i_op || !dir->i_op->mknod) {
- error = -ENOSYS; /* instead of EPERM, what does Posix say? */
- goto exit_inode;
- }
- atomic_inc(&dir->i_count);
+ goto exit_lock;
+
+ retval = ERR_PTR(-EPERM);
+ if (!dir->i_op || !dir->i_op->mknod)
+ goto exit_lock;
+
if (dir->i_sb && dir->i_sb->dq_op)
dir->i_sb->dq_op->initialize(dir, -1);
- down(&dir->i_sem);
- d_del(d_lookup(dir, &last, NULL), D_REMOVE);
- error = dir->i_op->mknod(dir, last.name, last.len, mode, dev);
-#ifdef CONFIG_OMIRR
- if(!error)
- omirr_print(dir->i_dentry, NULL, &last, " n %ld %d %d ",
- CURRENT_TIME, mode, dev);
-#endif
+ error = dir->i_op->mknod(dir, dentry, mode, dev);
+ retval = ERR_PTR(error);
+ if (!error)
+ retval = dget(dentry);
+
+exit_lock:
up(&dir->i_sem);
-exit_inode:
- if(!lasterror)
- iput(inode);
- iput(dir);
-exit:
- return error;
+ dput(dentry);
+ return retval;
}
asmlinkage int sys_mknod(const char * filename, int mode, dev_t dev)
@@ -864,68 +659,63 @@ asmlinkage int sys_mknod(const char * filename, int mode, dev_t dev)
default:
goto out;
}
- error = getname(filename,&tmp);
- if (!error) {
- error = do_mknod(tmp,mode,dev);
+ tmp = getname(filename);
+ error = PTR_ERR(tmp);
+ if (!IS_ERR(tmp)) {
+ struct dentry * dentry = do_mknod(tmp,mode,dev);
putname(tmp);
+ error = PTR_ERR(dentry);
+ if (!IS_ERR(dentry)) {
+ dput(dentry);
+ error = 0;
+ }
}
out:
unlock_kernel();
return error;
}
-/* [Feb-97 T. Schoebel-Theuer] remove_trailing_slashes() is now obsolete,
- * its functionality is handled by observing trailing slashes in __namei().
+/*
+ * Look out: this function may change a normal dentry
+ * into a directory dentry (different size)..
*/
static inline int do_mkdir(const char * pathname, int mode)
{
- char buf[MAX_TRANS_FILELEN+MAX_TRANS_SUFFIX+2];
- struct qstr last;
- int error, lasterror;
- struct inode * dir;
- struct inode * inode;
+ int error;
+ struct inode *dir;
+ struct dentry *dentry;
- mode &= 0777 & ~current->fs->umask;
+ dentry = lookup_dentry(pathname, NULL, 1);
+ error = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
+ goto exit;
+
+ dir = lock_parent(dentry);
+
+ error = -EEXIST;
+ if (dentry->d_inode)
+ goto exit_lock;
+
+ error = -EROFS;
+ if (IS_RDONLY(dir))
+ goto exit_lock;
- error = __namei(NAM_FOLLOW_LINK|NAM_TRANSCREATE, pathname, NULL, buf,
- &dir, &inode, &last, NULL, &lasterror);
+ error = permission(dir,MAY_WRITE | MAY_EXEC);
if (error)
- goto exit;
- if(!lasterror) {
- error = -EEXIST;
- goto exit_inode;
- }
- if (!last.len) {
- error = -ENOENT;
- goto exit_inode;
- }
- if (IS_RDONLY(dir)) {
- error = -EROFS;
- goto exit_inode;
- }
- if ((error = permission(dir,MAY_WRITE | MAY_EXEC)) != 0)
- goto exit_inode;
- if (!dir->i_op || !dir->i_op->mkdir) {
- error = -ENOSYS; /* instead of EPERM, what does Posix say? */
- goto exit_inode;
- }
- atomic_inc(&dir->i_count);
+ goto exit_lock;
+
+ error = -EPERM;
+ if (!dir->i_op || !dir->i_op->mkdir)
+ goto exit_lock;
+
if (dir->i_sb && dir->i_sb->dq_op)
dir->i_sb->dq_op->initialize(dir, -1);
- down(&dir->i_sem);
- d_del(d_lookup(dir, &last, NULL), D_REMOVE);
- mode &= 01777 & ~current->fs->umask;
- error = dir->i_op->mkdir(dir, last.name, last.len, mode);
-#ifdef CONFIG_OMIRR
- if(!error)
- omirr_print(dir->i_dentry, NULL, &last, " d %ld %d ",
- CURRENT_TIME, mode);
-#endif
+ mode &= 0777 & ~current->fs->umask;
+ error = dir->i_op->mkdir(dir, dentry, mode);
+
+exit_lock:
up(&dir->i_sem);
-exit_inode:
- if(!lasterror)
- iput(inode);
- iput(dir);
+ dput(dentry);
exit:
return error;
}
@@ -936,8 +726,9 @@ asmlinkage int sys_mkdir(const char * pathname, int mode)
char * tmp;
lock_kernel();
- error = getname(pathname,&tmp);
- if (!error) {
+ tmp = getname(pathname);
+ error = PTR_ERR(tmp);
+ if (!IS_ERR(tmp)) {
error = do_mkdir(tmp,mode);
putname(tmp);
}
@@ -945,124 +736,54 @@ asmlinkage int sys_mkdir(const char * pathname, int mode)
return error;
}
-#if 0 /* We need a "deletefs", someone please write it. -DaveM */
-/* Perhaps this could be moved out into a new file. */
-static void basket_name(struct inode * dir, struct dentry * entry)
-{
- char prefix[32];
- struct qstr prename = { prefix, 14 };
- struct qstr entname = { entry->d_name, entry->d_len };
- struct inode * inode;
- struct dentry * old = entry; /* dummy */
- int i;
- if(!entry || !(inode = d_inode(&entry)))
- return;
-#if 0
- if(atomic_read(&inode->i_count) > 2) {
- extern void printpath(struct dentry *entry);
-
- printk("Caution: in use ");
- if(inode->i_dentry)
- printpath(inode->i_dentry);
- printk(" i_nlink=%d i_count=%d i_ddir_count=%d i_dent_count=%d\n",
- inode->i_nlink, atomic_read(&inode->i_count),
- inode->i_ddir_count, inode->i_dent_count);
- }
-#endif
- vfs_lock();
- for(i = 1; old; i++) {
- sprintf(prefix, ".deleted-%04d.", i);
- old = d_lookup(dir, &prename, &entname);
- }
- d_move(entry, dir, &prename, &entname);
- vfs_unlock();
- iput(inode);
-}
-#endif
-
static inline int do_rmdir(const char * name)
{
- char buf[MAX_TRANS_FILELEN+MAX_TRANS_SUFFIX+2];
- struct qstr last;
- struct dentry * lastent = NULL;
int error;
- struct inode * dir;
- struct inode * inode;
-
- /* [T.Schoebel-Theuer] I'm not sure which flags to use here.
- * Try the following on different platforms:
- * [0] rm -rf test test2
- * [1] ln -s test2 test
- * [2] mkdir test || mkdir test2
- * [3] rmdir test && mkdir test2
- * [4] rmdir test/
- * Now the rusults:
- * cmd | HP-UX | SunOS | Solaris | Old Linux | New Linux |
- * ----------------------------------------------------------------
- * [2] | (OK) | EEXIST | EEXIST | EEXIST | (OK)
- * [3] | ENOTDIR | ENOTDIR | ENOTDIR | ENOTDIR | ENOTDIR
- * [4] | (OK) | EINVAL | ENOTDIR | ENOTDIR | (OK)
- * So I implemented the HP-UX semantics. If this is not right
- * for Posix compliancy, change the flags accordingly. If Posix
- * let the question open, I'd suggest to stay at the new semantics.
- * I'd even make case [3] work by adding 2 to the flags parameter
- * if Posix tolerates that.
- */
- error = __namei(NAM_FOLLOW_TRAILSLASH, name, NULL, buf,
- &dir, &inode, &last, &lastent, NULL);
- if (error)
+ struct inode *dir;
+ struct dentry *dentry;
+
+ dentry = lookup_dentry(name, NULL, 0);
+ error = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
goto exit;
- if (IS_RDONLY(dir)) {
- error = -EROFS;
- goto exit_dir;
- }
- if ((error = permission(dir,MAY_WRITE | MAY_EXEC)) != 0)
- goto exit_dir;
+
+ dir = lock_parent(dentry);
+ error = -ENOENT;
+ if (!dentry->d_inode)
+ goto exit_lock;
+
+ error = -EROFS;
+ if (IS_RDONLY(dir))
+ goto exit_lock;
+
+ error = permission(dir,MAY_WRITE | MAY_EXEC);
+ if (error)
+ goto exit_lock;
+
/*
* A subdirectory cannot be removed from an append-only directory.
*/
- if (IS_APPEND(dir)) {
- error = -EPERM;
- goto exit_dir;
- }
- if (!dir->i_op || !dir->i_op->rmdir) {
- error = -ENOSYS; /* was EPERM */
- goto exit_dir;
- }
+ error = -EPERM;
+ if (IS_APPEND(dir))
+ goto exit_lock;
+
/* Disallow removals of mountpoints. */
- if(inode->i_mount) {
- error = -EBUSY;
- goto exit_dir;
- }
+ error = -EBUSY;
+ if (dentry->d_covers != dentry)
+ goto exit_lock;
+
+ error = -EPERM;
+ if (!dir->i_op || !dir->i_op->rmdir)
+ goto exit_lock;
+
if (dir->i_sb && dir->i_sb->dq_op)
dir->i_sb->dq_op->initialize(dir, -1);
- down(&dir->i_sem);
-#if 0
- if(lastent && d_isbasket(lastent)) {
- d_del(lastent, D_REMOVE);
- error = 0;
- goto exit_lock;
- }
-#endif
- atomic_inc(&dir->i_count);
- error = dir->i_op->rmdir(dir, last.name, last.len);
-#ifdef CONFIG_OMIRR
- if(!error)
- omirr_print(lastent, NULL, NULL, " r %ld ", CURRENT_TIME);
-#endif
-#if 0
- if(!error && lastent)
- basket_name(dir, lastent);
+ error = dir->i_op->rmdir(dir, dentry);
+
exit_lock:
-#else
- if(!error && lastent)
- d_del(lastent, D_REMOVE);
-#endif
up(&dir->i_sem);
-exit_dir:
- iput(inode);
- iput(dir);
+ dput(dentry);
exit:
return error;
}
@@ -1073,8 +794,9 @@ asmlinkage int sys_rmdir(const char * pathname)
char * tmp;
lock_kernel();
- error = getname(pathname,&tmp);
- if (!error) {
+ tmp = getname(pathname);
+ error = PTR_ERR(tmp);
+ if (!IS_ERR(tmp)) {
error = do_rmdir(tmp);
putname(tmp);
}
@@ -1084,90 +806,44 @@ asmlinkage int sys_rmdir(const char * pathname)
static inline int do_unlink(const char * name)
{
- char buf[MAX_TRANS_FILELEN+MAX_TRANS_SUFFIX+2];
- struct qstr last;
- struct dentry * lastent = NULL;
int error;
- struct inode * dir;
- struct inode * inode;
-
- /* HP-UX shows a strange behaviour:
- * touch y; ln -s y x; rm x/
- * this succeeds and removes the file y, not the symlink x!
- * Solaris and old Linux remove the symlink instead, and
- * old SunOS complains ENOTDIR.
- * I chose the SunOS behaviour (by not using NAM_FOLLOW_TRAILSLASH),
- * but I'm not shure whether I should.
- * The current code generally prohibits using trailing slashes with
- * non-directories if the name already exists, but not if
- * it is to be newly created.
- * Perhaps this should be further strengthened (by introducing
- * an additional flag bit indicating whether trailing slashes are
- * allowed) to get it as consistant as possible, but I don't know
- * what Posix says.
- */
- error = __namei(NAM_NO_TRAILSLASH, name, NULL, buf,
- &dir, &inode, &last, &lastent, NULL);
- if (error)
+ struct inode *dir;
+ struct dentry *dentry;
+
+ dentry = lookup_dentry(name, NULL, 0);
+ error = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
goto exit;
- if (IS_RDONLY(dir)) {
- error = -EROFS;
- goto exit_dir;
- }
- if ((error = permission(dir,MAY_WRITE | MAY_EXEC)) != 0)
- goto exit_dir;
+
+ dir = lock_parent(dentry);
+
+ error = -EROFS;
+ if (IS_RDONLY(dir))
+ goto exit_lock;
+
+ error = permission(dir,MAY_WRITE | MAY_EXEC);
+ if (error)
+ goto exit_lock;
+
/*
* A file cannot be removed from an append-only directory.
*/
- if (IS_APPEND(dir)) {
- error = -EPERM;
- goto exit_dir;
- }
- if (!dir->i_op || !dir->i_op->unlink) {
- error = -ENOSYS; /* was EPERM */
- goto exit_dir;
- }
+ error = -EPERM;
+ if (IS_APPEND(dir))
+ goto exit_lock;
+
+ error = -EPERM;
+ if (!dir->i_op || !dir->i_op->unlink)
+ goto exit_lock;
+
if (dir->i_sb && dir->i_sb->dq_op)
dir->i_sb->dq_op->initialize(dir, -1);
- down(&dir->i_sem);
-#if 0
- if(atomic_read(&inode->i_count) > 1) {
- extern void printpath(struct dentry *entry);
-
- printk("Fire ");
- if(lastent)
- printpath(lastent);
- printk(" i_nlink=%d i_count=%d i_ddir_count=%d i_dent_count=%d\n",
- inode->i_nlink, atomic_read(&inode->i_count),
- inode->i_ddir_count, inode->i_dent_count);
- }
-#endif
-#if 0
- if(lastent && d_isbasket(lastent)) {
- d_del(lastent, D_REMOVE);
- error = 0;
- goto exit_lock;
- }
-#endif
- atomic_inc(&dir->i_count);
- error = dir->i_op->unlink(dir, last.name, last.len);
-#ifdef CONFIG_OMIRR
- if(!error)
- omirr_print(lastent, NULL, NULL, " u %ld ", CURRENT_TIME);
-#endif
-#if 0
- if(!error && lastent)
- basket_name(dir, lastent);
+ error = dir->i_op->unlink(dir, dentry);
+
exit_lock:
-#else
- if(!error && lastent)
- d_del(lastent, D_REMOVE);
-#endif
up(&dir->i_sem);
-exit_dir:
- iput(inode);
- iput(dir);
+ dput(dentry);
exit:
return error;
}
@@ -1178,8 +854,9 @@ asmlinkage int sys_unlink(const char * pathname)
char * tmp;
lock_kernel();
- error = getname(pathname,&tmp);
- if (!error) {
+ tmp = getname(pathname);
+ error = PTR_ERR(tmp);
+ if (!IS_ERR(tmp)) {
error = do_unlink(tmp);
putname(tmp);
}
@@ -1189,62 +866,41 @@ asmlinkage int sys_unlink(const char * pathname)
static inline int do_symlink(const char * oldname, const char * newname)
{
- char buf[MAX_TRANS_FILELEN+MAX_TRANS_SUFFIX+2];
- struct qstr last;
- int error, lasterror;
- struct inode * dir;
- struct inode * inode;
-
- /* The following works on HP-UX and Solaris, by producing
- * a symlink chain:
- * rm -rf ? ; mkdir z ; ln -s z y ; ln -s y x/
- * Under old SunOS, the following occurs:
- * ln: x/: No such file or directory
- * Under old Linux, very strange things occur:
- * ln: cannot create symbolic link `x//y' to `y': No such file or directory
- * This is very probably a bug, but may be caused by the ln program
- * when checking for a directory target.
- *
- * I'm not shure whether to add NAM_NO_TRAILSLASH to inhibit trailing
- * slashes in the target generally.
- */
- error = __namei(NAM_TRANSCREATE, newname, NULL, buf,
- &dir, &inode, &last, NULL, &lasterror);
- if (error)
+ int error;
+ struct inode *dir;
+ struct dentry *dentry;
+
+ dentry = lookup_dentry(newname, NULL, 0);
+
+ error = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
goto exit;
- if(!lasterror) {
- iput(inode);
- error = -EEXIST;
- goto exit_dir;
- }
- if (!last.len) {
- error = -ENOENT;
- goto exit_dir;
- }
- if (IS_RDONLY(dir)) {
- error = -EROFS;
- goto exit_dir;
- }
- if ((error = permission(dir,MAY_WRITE | MAY_EXEC)) != 0)
- goto exit_dir;
- if (!dir->i_op || !dir->i_op->symlink) {
- error = -ENOSYS; /* was EPERM */
- goto exit_dir;
- }
- atomic_inc(&dir->i_count);
+
+ error = -EEXIST;
+ if (dentry->d_inode)
+ goto exit;
+
+ dir = lock_parent(dentry);
+
+ error = -EROFS;
+ if (IS_RDONLY(dir))
+ goto exit_lock;
+
+ error = permission(dir,MAY_WRITE | MAY_EXEC);
+ if (error)
+ goto exit_lock;
+
+ error = -EPERM;
+ if (!dir->i_op || !dir->i_op->symlink)
+ goto exit_lock;
+
if (dir->i_sb && dir->i_sb->dq_op)
dir->i_sb->dq_op->initialize(dir, -1);
- down(&dir->i_sem);
- d_del(d_lookup(dir, &last, NULL), D_REMOVE);
- error = dir->i_op->symlink(dir, last.name, last.len, oldname);
-#ifdef CONFIG_OMIRR
- if(!error)
- omirr_print(dir->i_dentry, NULL, &last,
- " s %ld %s\0", CURRENT_TIME, oldname);
-#endif
+ error = dir->i_op->symlink(dir, dentry, oldname);
+
+exit_lock:
up(&dir->i_sem);
-exit_dir:
- iput(dir);
+ dput(dentry);
exit:
return error;
}
@@ -1252,13 +908,16 @@ exit:
asmlinkage int sys_symlink(const char * oldname, const char * newname)
{
int error;
- char * from, * to;
+ char * from;
lock_kernel();
- error = getname(oldname,&from);
- if (!error) {
- error = getname(newname,&to);
- if (!error) {
+ from = getname(oldname);
+ error = PTR_ERR(from);
+ if (!IS_ERR(from)) {
+ char * to;
+ to = getname(newname);
+ error = PTR_ERR(to);
+ if (!IS_ERR(to)) {
error = do_symlink(from,to);
putname(to);
}
@@ -1270,73 +929,63 @@ asmlinkage int sys_symlink(const char * oldname, const char * newname)
static inline int do_link(const char * oldname, const char * newname)
{
- char oldbuf[MAX_TRANS_FILELEN+MAX_TRANS_SUFFIX+2];
- char newbuf[MAX_TRANS_FILELEN+MAX_TRANS_SUFFIX+2];
- struct qstr oldlast;
- struct qstr newlast;
- struct dentry * oldent = NULL;
- struct inode * oldinode;
- struct inode * newinode;
- struct inode * newdir;
- int error, lasterror;
-
- error = __namei(NAM_FOLLOW_LINK|NAM_NO_TRAILSLASH,
- oldname, NULL, oldbuf,
- NULL, &oldinode, &oldlast, &oldent, NULL);
- if (error)
+ struct dentry *old_dentry, *new_dentry;
+ struct inode *dir, *inode;
+ int error;
+
+ old_dentry = lookup_dentry(oldname, NULL, 1);
+ error = PTR_ERR(old_dentry);
+ if (IS_ERR(old_dentry))
goto exit;
- error = __namei(NAM_FOLLOW_LINK|NAM_TRANSCREATE, newname, NULL, newbuf,
- &newdir, &newinode, &newlast, NULL, &lasterror);
+ new_dentry = lookup_dentry(newname, NULL, 1);
+ error = PTR_ERR(new_dentry);
+ if (IS_ERR(new_dentry))
+ goto exit_old;
+
+ dir = lock_parent(new_dentry);
+
+ error = -ENOENT;
+ inode = old_dentry->d_inode;
+ if (!inode)
+ goto exit_lock;
+
+ error = -EEXIST;
+ if (new_dentry->d_inode)
+ goto exit_lock;
+
+ error = -EROFS;
+ if (IS_RDONLY(dir))
+ goto exit_lock;
+
+ error = -EXDEV;
+ if (dir->i_dev != inode->i_dev)
+ goto exit_lock;
+
+ error = permission(dir, MAY_WRITE | MAY_EXEC);
if (error)
- goto old_exit;
- if(!lasterror) {
- iput(newinode);
- error = -EEXIST;
- goto new_exit;
- }
- if (!newlast.len) {
- error = -EPERM;
- goto new_exit;
- }
- if (IS_RDONLY(newdir)) {
- error = -EROFS;
- goto new_exit;
- }
- if (newdir->i_dev != oldinode->i_dev) {
- error = -EXDEV;
- goto new_exit;
- }
- if ((error = permission(newdir,MAY_WRITE | MAY_EXEC)) != 0)
- goto new_exit;
+ goto exit_lock;
+
/*
* A link to an append-only or immutable file cannot be created.
*/
- if (IS_APPEND(oldinode) || IS_IMMUTABLE(oldinode)) {
- error = -EPERM;
- goto new_exit;
- }
- if (!newdir->i_op || !newdir->i_op->link) {
- error = -ENOSYS; /* was EPERM */
- goto new_exit;
- }
- atomic_inc(&oldinode->i_count);
- atomic_inc(&newdir->i_count);
- if (newdir->i_sb && newdir->i_sb->dq_op)
- newdir->i_sb->dq_op->initialize(newdir, -1);
- down(&newdir->i_sem);
- d_del(d_lookup(newdir, &newlast, NULL), D_REMOVE);
- error = newdir->i_op->link(oldinode, newdir, newlast.name, newlast.len);
-#ifdef CONFIG_OMIRR
- if(!error)
- omirr_print(oldent, newdir->i_dentry, &newlast,
- " l %ld ", CURRENT_TIME);
-#endif
- up(&newdir->i_sem);
-new_exit:
- iput(newdir);
-old_exit:
- iput(oldinode);
+ error = -EPERM;
+ if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+ goto exit_lock;
+
+ error = -EPERM;
+ if (!dir->i_op || !dir->i_op->link)
+ goto exit_lock;
+
+ if (dir->i_sb && dir->i_sb->dq_op)
+ dir->i_sb->dq_op->initialize(dir, -1);
+ error = dir->i_op->link(inode, dir, new_dentry);
+
+exit_lock:
+ up(&dir->i_sem);
+ dput(new_dentry);
+exit_old:
+ dput(old_dentry);
exit:
return error;
}
@@ -1344,13 +993,16 @@ exit:
asmlinkage int sys_link(const char * oldname, const char * newname)
{
int error;
- char * from, * to;
+ char * from;
lock_kernel();
- error = getname(oldname,&from);
- if (!error) {
- error = getname(newname,&to);
- if (!error) {
+ from = getname(oldname);
+ error = PTR_ERR(from);
+ if (!IS_ERR(from)) {
+ char * to;
+ to = getname(newname);
+ error = PTR_ERR(to);
+ if (!IS_ERR(to)) {
error = do_link(from,to);
putname(to);
}
@@ -1360,105 +1012,111 @@ asmlinkage int sys_link(const char * oldname, const char * newname)
return error;
}
-static inline int do_rename(const char * oldname, const char * newname)
+/*
+ * Whee.. Deadlock country. Happily there is only one VFS
+ * operation that does this..
+ */
+static inline void double_down(struct semaphore *s1, struct semaphore *s2)
{
- char oldbuf[MAX_TRANS_FILELEN+MAX_TRANS_SUFFIX+2];
- struct qstr oldlast;
- char newbuf[MAX_TRANS_FILELEN+MAX_TRANS_SUFFIX+2];
- struct qstr newlast;
- struct dentry * oldent = NULL;
- struct inode * olddir, * newdir;
- struct inode * oldinode, * newinode;
- int error, newlasterror;
-
- error = __namei(NAM_FOLLOW_TRAILSLASH, oldname, NULL, oldbuf,
- &olddir, &oldinode, &oldlast, &oldent, NULL);
- if (error)
- goto exit;
- if ((error = permission(olddir,MAY_WRITE | MAY_EXEC)) != 0)
- goto old_exit;
- if (!oldlast.len || (oldlast.name[0] == '.' &&
- (oldlast.len == 1 || (oldlast.name[1] == '.' &&
- oldlast.len == 2)))) {
- error = -EPERM;
- goto old_exit;
+ if ((unsigned long) s1 < (unsigned long) s2) {
+ down(s1);
+ down(s2);
+ } else if (s1 == s2) {
+ down(s1);
+ atomic_dec(&s1->count);
+ } else {
+ down(s2);
+ down(s1);
}
- /* Disallow moves of mountpoints. */
- if(oldinode->i_mount) {
- error = -EBUSY;
- goto old_exit;
+}
+
+static inline int is_reserved(struct dentry *dentry)
+{
+ if (dentry->d_name.name[0] == '.') {
+ switch (dentry->d_name.len) {
+ case 2:
+ if (dentry->d_name.name[1] != '.')
+ break;
+ /* fallthrough */
+ case 1:
+ return 1;
+ }
}
+ return 0;
+}
+
+static inline int do_rename(const char * oldname, const char * newname)
+{
+ int error;
+ struct inode * old_dir, * new_dir;
+ struct dentry * old_dentry, *new_dentry;
+
+ old_dentry = lookup_dentry(oldname, NULL, 0);
+
+ error = PTR_ERR(old_dentry);
+ if (IS_ERR(old_dentry))
+ goto exit;
+
+ new_dentry = lookup_dentry(newname, NULL, 0);
+
+ error = PTR_ERR(new_dentry);
+ if (IS_ERR(new_dentry))
+ goto exit_old;
+
+ new_dir = get_parent(new_dentry);
+ old_dir = get_parent(old_dentry);
+
+ double_down(&new_dir->i_sem, &old_dir->i_sem);
- error = __namei(NAM_FOLLOW_LINK|NAM_TRANSCREATE, newname, NULL, newbuf,
- &newdir, &newinode, &newlast, NULL, &newlasterror);
+ error = -ENOENT;
+ if (!old_dentry->d_inode)
+ goto exit_lock;
+
+ error = permission(old_dir,MAY_WRITE | MAY_EXEC);
if (error)
- goto old_exit;
- if ((error = permission(newdir,MAY_WRITE | MAY_EXEC)) != 0)
- goto new_exit;
- if (!newlast.len || (newlast.name[0] == '.' &&
- (newlast.len == 1 || (newlast.name[1] == '.' &&
- newlast.len == 2)))) {
- error = -EPERM;
- goto new_exit;
- }
- if (newdir->i_dev != olddir->i_dev) {
- error = -EXDEV;
- goto new_exit;
- }
- if (IS_RDONLY(newdir) || IS_RDONLY(olddir)) {
- error = -EROFS;
- goto new_exit;
- }
+ goto exit_lock;
+ error = permission(new_dir,MAY_WRITE | MAY_EXEC);
+ if (error)
+ goto exit_lock;
+
+ error = -EPERM;
+ if (is_reserved(new_dentry) || is_reserved(old_dentry))
+ goto exit_lock;
+
+ /* Disallow moves of mountpoints. */
+ error = -EBUSY;
+ if (old_dentry->d_covers != old_dentry)
+ goto exit_lock;
+
+ error = -EXDEV;
+ if (new_dir->i_dev != old_dir->i_dev)
+ goto exit_lock;
+
+ error = -EROFS;
+ if (IS_RDONLY(new_dir) || IS_RDONLY(old_dir))
+ goto exit_lock;
+
/*
* A file cannot be removed from an append-only directory.
*/
- if (IS_APPEND(olddir)) {
- error = -EPERM;
- goto new_exit;
- }
- if (!olddir->i_op || !olddir->i_op->rename) {
- error = -ENOSYS; /* was EPERM */
- goto new_exit;
- }
-#ifdef CONFIG_TRANS_NAMES
- /* if oldname has been translated, but newname not (and
- * has not already a suffix), take over the suffix from oldname.
- */
- if(oldlast.name == oldbuf && newlast.name != newbuf &&
- newlast.name[newlast.len-1] != '#') {
- int i = oldlast.len - 2;
- while (i > 0 && oldlast.name[i] != '#')
- i--;
- memcpy(newbuf, newlast.name, newlast.len);
- memcpy(newbuf+newlast.len, oldlast.name+i, oldlast.len - i);
- newlast.len += oldlast.len - i;
- newlast.name = newbuf;
- }
-#endif
- atomic_inc(&olddir->i_count);
- atomic_inc(&newdir->i_count);
- if (newdir->i_sb && newdir->i_sb->dq_op)
- newdir->i_sb->dq_op->initialize(newdir, -1);
- down(&newdir->i_sem);
- error = olddir->i_op->rename(olddir, oldlast.name, oldlast.len,
- newdir, newlast.name, newlast.len);
-#ifdef CONFIG_OMIRR
- if(!error)
- omirr_print(oldent, newdir->i_dentry, &newlast,
- " m %ld ", CURRENT_TIME);
-#endif
- if(!error) {
- d_del(d_lookup(newdir, &newlast, NULL), D_REMOVE);
- d_move(d_lookup(olddir, &oldlast, NULL), newdir, &newlast, NULL);
- }
- up(&newdir->i_sem);
-new_exit:
- if(!newlasterror)
- iput(newinode);
- iput(newdir);
-old_exit:
- iput(oldinode);
- iput(olddir);
+ error = -EPERM;
+ if (IS_APPEND(old_dir))
+ goto exit_lock;
+
+ error = -EPERM;
+ if (!old_dir->i_op || !old_dir->i_op->rename)
+ goto exit_lock;
+
+ if (new_dir->i_sb && new_dir->i_sb->dq_op)
+ new_dir->i_sb->dq_op->initialize(new_dir, -1);
+ error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
+
+exit_lock:
+ up(&new_dir->i_sem);
+ up(&old_dir->i_sem);
+ dput(new_dentry);
+exit_old:
+ dput(old_dentry);
exit:
return error;
}
@@ -1466,13 +1124,16 @@ exit:
asmlinkage int sys_rename(const char * oldname, const char * newname)
{
int error;
- char * from, * to;
+ char * from;
lock_kernel();
- error = getname(oldname,&from);
- if (!error) {
- error = getname(newname,&to);
- if (!error) {
+ from = getname(oldname);
+ error = PTR_ERR(from);
+ if (!IS_ERR(from)) {
+ char * to;
+ to = getname(newname);
+ error = PTR_ERR(to);
+ if (!IS_ERR(to)) {
error = do_rename(from,to);
putname(to);
}