fedora core 6 1.2949 + vserver 2.2.0

[linux-2.6.git] / fs / fuse / dir.c

diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index f75deeb..4008047 100644 (file)
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -139,9 +139,7 @@ static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd)
                struct fuse_conn *fc;
                struct fuse_req *req;
                struct fuse_req *forget_req;
-
-               /* Doesn't hurt to "reset" the validity timeout */
-               fuse_invalidate_entry_cache(entry);
+               struct dentry *parent;
 
                /* For negative dentries, always do a fresh lookup */
                if (!inode)
@@ -158,8 +156,10 @@ static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd)
                        return 0;
                }
 
-               fuse_lookup_init(req, entry->d_parent->d_inode, entry, &outarg);
+               parent = dget_parent(entry);
+               fuse_lookup_init(req, parent->d_inode, entry, &outarg);
                request_send(fc, req);
+               dput(parent);
                err = req->out.h.error;
                fuse_put_request(fc, req);
                /* Zero nodeid is same as -ENOENT */
@@ -172,7 +172,9 @@ static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd)
                                                 outarg.nodeid, 1);
                                return 0;
                        }
+                       spin_lock(&fc->lock);
                        fi->nlookup ++;
+                       spin_unlock(&fc->lock);
                }
                fuse_put_request(fc, forget_req);
                if (err || (outarg.attr.mode ^ inode->i_mode) & S_IFMT)
@@ -184,22 +186,6 @@ static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd)
        return 1;
 }
 
-/*
- * Check if there's already a hashed alias of this directory inode.
- * If yes, then lookup and mkdir must not create a new alias.
- */
-static int dir_alias(struct inode *inode)
-{
-       if (S_ISDIR(inode->i_mode)) {
-               struct dentry *alias = d_find_alias(inode);
-               if (alias) {
-                       dput(alias);
-                       return 1;
-               }
-       }
-       return 0;
-}
-
 static int invalid_nodeid(u64 nodeid)
 {
        return !nodeid || nodeid == FUSE_ROOT_ID;
@@ -215,6 +201,24 @@ static int valid_mode(int m)
                S_ISBLK(m) || S_ISFIFO(m) || S_ISSOCK(m);
 }
 
+/*
+ * Add a directory inode to a dentry, ensuring that no other dentry
+ * refers to this inode.  Called with fc->inst_mutex.
+ */
+static int fuse_d_add_directory(struct dentry *entry, struct inode *inode)
+{
+       struct dentry *alias = d_find_alias(inode);
+       if (alias) {
+               /* This tries to shrink the subtree below alias */
+               fuse_invalidate_entry(alias);
+               dput(alias);
+               if (!list_empty(&inode->i_dentry))
+                       return -EBUSY;
+       }
+       d_add(entry, inode);
+       return 0;
+}
+
 static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
                                  struct nameidata *nd)
 {
@@ -258,11 +262,17 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
        if (err && err != -ENOENT)
                return ERR_PTR(err);
 
-       if (inode && dir_alias(inode)) {
-               iput(inode);
-               return ERR_PTR(-EIO);
-       }
-       d_add(entry, inode);
+       if (inode && S_ISDIR(inode->i_mode)) {
+               mutex_lock(&fc->inst_mutex);
+               err = fuse_d_add_directory(entry, inode);
+               mutex_unlock(&fc->inst_mutex);
+               if (err) {
+                       iput(inode);
+                       return ERR_PTR(err);
+               }
+       } else
+               d_add(entry, inode);
+
        entry->d_op = &fuse_dentry_operations;
        if (!err)
                fuse_change_timeout(entry, &outarg);
@@ -425,12 +435,22 @@ static int create_new_entry(struct fuse_conn *fc, struct fuse_req *req,
        }
        fuse_put_request(fc, forget_req);
 
-       if (dir_alias(inode)) {
-               iput(inode);
-               return -EIO;
-       }
+       if (S_ISDIR(inode->i_mode)) {
+               struct dentry *alias;
+               mutex_lock(&fc->inst_mutex);
+               alias = d_find_alias(inode);
+               if (alias) {
+                       /* New directory must have moved since mkdir */
+                       mutex_unlock(&fc->inst_mutex);
+                       dput(alias);
+                       iput(inode);
+                       return -EBUSY;
+               }
+               d_instantiate(entry, inode);
+               mutex_unlock(&fc->inst_mutex);
+       } else
+               d_instantiate(entry, inode);
 
-       d_instantiate(entry, inode);
        fuse_change_timeout(entry, &outarg);
        fuse_invalidate_attr(dir);
        return 0;
@@ -532,7 +552,7 @@ static int fuse_unlink(struct inode *dir, struct dentry *entry)
                /* Set nlink to zero so the inode can be cleared, if
                    the inode does have more links this will be
                    discovered at the next lookup/getattr */
-               inode->i_nlink = 0;
+               clear_nlink(inode);
                fuse_invalidate_attr(inode);
                fuse_invalidate_attr(dir);
                fuse_invalidate_entry_cache(entry);
@@ -558,7 +578,7 @@ static int fuse_rmdir(struct inode *dir, struct dentry *entry)
        err = req->out.h.error;
        fuse_put_request(fc, req);
        if (!err) {
-               entry->d_inode->i_nlink = 0;
+               clear_nlink(entry->d_inode);
                fuse_invalidate_attr(dir);
                fuse_invalidate_entry_cache(entry);
        } else if (err == -EINTR)
@@ -800,7 +820,7 @@ static int fuse_permission(struct inode *inode, int mask, struct nameidata *nd)
                if ((mask & MAY_EXEC) && !S_ISDIR(mode) && !(mode & S_IXUGO))
                        return -EACCES;
 
-               if (nd && (nd->flags & LOOKUP_ACCESS))
+               if (nd && (nd->flags & (LOOKUP_ACCESS | LOOKUP_CHDIR)))
                        return fuse_access(inode, mask);
                return 0;
        }
@@ -836,7 +856,7 @@ static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir)
        int err;
        size_t nbytes;
        struct page *page;
-       struct inode *inode = file->f_dentry->d_inode;
+       struct inode *inode = file->f_path.dentry->d_inode;
        struct fuse_conn *fc = get_fuse_conn(inode);
        struct fuse_req *req;
 
@@ -1004,6 +1024,8 @@ static int fuse_setattr(struct dentry *entry, struct iattr *attr)
        if (attr->ia_valid & ATTR_SIZE) {
                unsigned long limit;
                is_truncate = 1;
+               if (IS_SWAPFILE(inode))
+                       return -ETXTBSY;
                limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
                if (limit != RLIM_INFINITY && attr->ia_size > (loff_t) limit) {
                        send_sig(SIGXFSZ, current, 0);