]> err.no Git - linux-2.6/blobdiff - fs/fuse/dir.c
SL*B: drop kmem cache argument from constructor
[linux-2.6] / fs / fuse / dir.c
index 052327bd6c9dcb42587073ebb0de65cc0d94f5f1..51d0035ff07e3a59037324ef256eb6b849163deb 100644 (file)
@@ -97,7 +97,7 @@ void fuse_invalidate_attr(struct inode *inode)
  * timeout is unknown (unlink, rmdir, rename and in some cases
  * lookup)
  */
-static void fuse_invalidate_entry_cache(struct dentry *entry)
+void fuse_invalidate_entry_cache(struct dentry *entry)
 {
        fuse_dentry_settime(entry, 0);
 }
@@ -112,20 +112,39 @@ static void fuse_invalidate_entry(struct dentry *entry)
        fuse_invalidate_entry_cache(entry);
 }
 
-static void fuse_lookup_init(struct fuse_req *req, struct inode *dir,
-                            struct dentry *entry,
+static void fuse_lookup_init(struct fuse_conn *fc, struct fuse_req *req,
+                            u64 nodeid, struct qstr *name,
                             struct fuse_entry_out *outarg)
 {
+       memset(outarg, 0, sizeof(struct fuse_entry_out));
        req->in.h.opcode = FUSE_LOOKUP;
-       req->in.h.nodeid = get_node_id(dir);
+       req->in.h.nodeid = nodeid;
        req->in.numargs = 1;
-       req->in.args[0].size = entry->d_name.len + 1;
-       req->in.args[0].value = entry->d_name.name;
+       req->in.args[0].size = name->len + 1;
+       req->in.args[0].value = name->name;
        req->out.numargs = 1;
-       req->out.args[0].size = sizeof(struct fuse_entry_out);
+       if (fc->minor < 9)
+               req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
+       else
+               req->out.args[0].size = sizeof(struct fuse_entry_out);
        req->out.args[0].value = outarg;
 }
 
+u64 fuse_get_attr_version(struct fuse_conn *fc)
+{
+       u64 curr_version;
+
+       /*
+        * The spin lock isn't actually needed on 64bit archs, but we
+        * don't yet care too much about such optimizations.
+        */
+       spin_lock(&fc->lock);
+       curr_version = fc->attr_version;
+       spin_unlock(&fc->lock);
+
+       return curr_version;
+}
+
 /*
  * Check whether the dentry is still valid
  *
@@ -165,12 +184,11 @@ static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd)
                        return 0;
                }
 
-               spin_lock(&fc->lock);
-               attr_version = fc->attr_version;
-               spin_unlock(&fc->lock);
+               attr_version = fuse_get_attr_version(fc);
 
                parent = dget_parent(entry);
-               fuse_lookup_init(req, parent->d_inode, entry, &outarg);
+               fuse_lookup_init(fc, req, get_node_id(parent->d_inode),
+                                &entry->d_name, &outarg);
                request_send(fc, req);
                dput(parent);
                err = req->out.h.error;
@@ -206,7 +224,7 @@ static int invalid_nodeid(u64 nodeid)
        return !nodeid || nodeid == FUSE_ROOT_ID;
 }
 
-static struct dentry_operations fuse_dentry_operations = {
+struct dentry_operations fuse_dentry_operations = {
        .d_revalidate   = fuse_dentry_revalidate,
 };
 
@@ -220,87 +238,127 @@ int fuse_valid_type(int 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)
+static struct dentry *fuse_d_add_directory(struct dentry *entry,
+                                          struct inode *inode)
 {
        struct dentry *alias = d_find_alias(inode);
-       if (alias) {
+       if (alias && !(alias->d_flags & DCACHE_DISCONNECTED)) {
                /* This tries to shrink the subtree below alias */
                fuse_invalidate_entry(alias);
                dput(alias);
                if (!list_empty(&inode->i_dentry))
-                       return -EBUSY;
+                       return ERR_PTR(-EBUSY);
+       } else {
+               dput(alias);
        }
-       d_add(entry, inode);
-       return 0;
+       return d_splice_alias(inode, entry);
 }
 
-static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
-                                 struct nameidata *nd)
+int fuse_lookup_name(struct super_block *sb, u64 nodeid, struct qstr *name,
+                    struct fuse_entry_out *outarg, struct inode **inode)
 {
-       int err;
-       struct fuse_entry_out outarg;
-       struct inode *inode = NULL;
-       struct fuse_conn *fc = get_fuse_conn(dir);
+       struct fuse_conn *fc = get_fuse_conn_super(sb);
        struct fuse_req *req;
        struct fuse_req *forget_req;
        u64 attr_version;
+       int err;
 
-       if (entry->d_name.len > FUSE_NAME_MAX)
-               return ERR_PTR(-ENAMETOOLONG);
+       *inode = NULL;
+       err = -ENAMETOOLONG;
+       if (name->len > FUSE_NAME_MAX)
+               goto out;
 
        req = fuse_get_req(fc);
+       err = PTR_ERR(req);
        if (IS_ERR(req))
-               return ERR_PTR(PTR_ERR(req));
+               goto out;
 
        forget_req = fuse_get_req(fc);
+       err = PTR_ERR(forget_req);
        if (IS_ERR(forget_req)) {
                fuse_put_request(fc, req);
-               return ERR_PTR(PTR_ERR(forget_req));
+               goto out;
        }
 
-       spin_lock(&fc->lock);
-       attr_version = fc->attr_version;
-       spin_unlock(&fc->lock);
+       attr_version = fuse_get_attr_version(fc);
 
-       fuse_lookup_init(req, dir, entry, &outarg);
+       fuse_lookup_init(fc, req, nodeid, name, outarg);
        request_send(fc, req);
        err = req->out.h.error;
        fuse_put_request(fc, req);
        /* Zero nodeid is same as -ENOENT, but with valid timeout */
-       if (!err && outarg.nodeid &&
-           (invalid_nodeid(outarg.nodeid) ||
-            !fuse_valid_type(outarg.attr.mode)))
-               err = -EIO;
-       if (!err && outarg.nodeid) {
-               inode = fuse_iget(dir->i_sb, outarg.nodeid, outarg.generation,
-                                 &outarg.attr, entry_attr_timeout(&outarg),
-                                 attr_version);
-               if (!inode) {
-                       fuse_send_forget(fc, forget_req, outarg.nodeid, 1);
-                       return ERR_PTR(-ENOMEM);
-               }
+       if (err || !outarg->nodeid)
+               goto out_put_forget;
+
+       err = -EIO;
+       if (!outarg->nodeid)
+               goto out_put_forget;
+       if (!fuse_valid_type(outarg->attr.mode))
+               goto out_put_forget;
+
+       *inode = fuse_iget(sb, outarg->nodeid, outarg->generation,
+                          &outarg->attr, entry_attr_timeout(outarg),
+                          attr_version);
+       err = -ENOMEM;
+       if (!*inode) {
+               fuse_send_forget(fc, forget_req, outarg->nodeid, 1);
+               goto out;
        }
+       err = 0;
+
+ out_put_forget:
        fuse_put_request(fc, forget_req);
-       if (err && err != -ENOENT)
-               return ERR_PTR(err);
+ out:
+       return err;
+}
+
+static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
+                                 struct nameidata *nd)
+{
+       int err;
+       struct fuse_entry_out outarg;
+       struct inode *inode;
+       struct dentry *newent;
+       struct fuse_conn *fc = get_fuse_conn(dir);
+       bool outarg_valid = true;
+
+       err = fuse_lookup_name(dir->i_sb, get_node_id(dir), &entry->d_name,
+                              &outarg, &inode);
+       if (err == -ENOENT) {
+               outarg_valid = false;
+               err = 0;
+       }
+       if (err)
+               goto out_err;
+
+       err = -EIO;
+       if (inode && get_node_id(inode) == FUSE_ROOT_ID)
+               goto out_iput;
 
        if (inode && S_ISDIR(inode->i_mode)) {
                mutex_lock(&fc->inst_mutex);
-               err = fuse_d_add_directory(entry, inode);
+               newent = fuse_d_add_directory(entry, inode);
                mutex_unlock(&fc->inst_mutex);
-               if (err) {
-                       iput(inode);
-                       return ERR_PTR(err);
-               }
-       } else
-               d_add(entry, inode);
+               err = PTR_ERR(newent);
+               if (IS_ERR(newent))
+                       goto out_iput;
+       } else {
+               newent = d_splice_alias(inode, entry);
+       }
 
+       entry = newent ? newent : entry;
        entry->d_op = &fuse_dentry_operations;
-       if (!err)
+       if (outarg_valid)
                fuse_change_entry_timeout(entry, &outarg);
        else
                fuse_invalidate_entry_cache(entry);
-       return NULL;
+
+       return newent;
+
+ out_iput:
+       iput(inode);
+ out_err:
+       return ERR_PTR(err);
 }
 
 /*
@@ -356,6 +414,7 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, int mode,
 
        flags &= ~O_NOCTTY;
        memset(&inarg, 0, sizeof(inarg));
+       memset(&outentry, 0, sizeof(outentry));
        inarg.flags = flags;
        inarg.mode = mode;
        req->in.h.opcode = FUSE_CREATE;
@@ -366,7 +425,10 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, int mode,
        req->in.args[1].size = entry->d_name.len + 1;
        req->in.args[1].value = entry->d_name.name;
        req->out.numargs = 2;
-       req->out.args[0].size = sizeof(outentry);
+       if (fc->minor < 9)
+               req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
+       else
+               req->out.args[0].size = sizeof(outentry);
        req->out.args[0].value = &outentry;
        req->out.args[1].size = sizeof(outopen);
        req->out.args[1].value = &outopen;
@@ -395,6 +457,7 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, int mode,
        fuse_put_request(fc, forget_req);
        d_instantiate(entry, inode);
        fuse_change_entry_timeout(entry, &outentry);
+       fuse_invalidate_attr(dir);
        file = lookup_instantiate_filp(nd, entry, generic_file_open);
        if (IS_ERR(file)) {
                ff->fh = outopen.fh;
@@ -431,9 +494,13 @@ static int create_new_entry(struct fuse_conn *fc, struct fuse_req *req,
                return PTR_ERR(forget_req);
        }
 
+       memset(&outarg, 0, sizeof(outarg));
        req->in.h.nodeid = get_node_id(dir);
        req->out.numargs = 1;
-       req->out.args[0].size = sizeof(outarg);
+       if (fc->minor < 9)
+               req->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
+       else
+               req->out.args[0].size = sizeof(outarg);
        req->out.args[0].value = &outarg;
        request_send(fc, req);
        err = req->out.h.error;
@@ -632,6 +699,9 @@ static int fuse_rename(struct inode *olddir, struct dentry *oldent,
        err = req->out.h.error;
        fuse_put_request(fc, req);
        if (!err) {
+               /* ctime changes */
+               fuse_invalidate_attr(oldent->d_inode);
+
                fuse_invalidate_attr(olddir);
                if (olddir != newdir)
                        fuse_invalidate_attr(newdir);
@@ -719,11 +789,10 @@ static int fuse_do_getattr(struct inode *inode, struct kstat *stat,
        if (IS_ERR(req))
                return PTR_ERR(req);
 
-       spin_lock(&fc->lock);
-       attr_version = fc->attr_version;
-       spin_unlock(&fc->lock);
+       attr_version = fuse_get_attr_version(fc);
 
        memset(&inarg, 0, sizeof(inarg));
+       memset(&outarg, 0, sizeof(outarg));
        /* Directories have separate file-handle space */
        if (file && S_ISREG(inode->i_mode)) {
                struct fuse_file *ff = file->private_data;
@@ -737,7 +806,10 @@ static int fuse_do_getattr(struct inode *inode, struct kstat *stat,
        req->in.args[0].size = sizeof(inarg);
        req->in.args[0].value = &inarg;
        req->out.numargs = 1;
-       req->out.args[0].size = sizeof(outarg);
+       if (fc->minor < 9)
+               req->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
+       else
+               req->out.args[0].size = sizeof(outarg);
        req->out.args[0].value = &outarg;
        request_send(fc, req);
        err = req->out.h.error;
@@ -757,6 +829,31 @@ static int fuse_do_getattr(struct inode *inode, struct kstat *stat,
        return err;
 }
 
+int fuse_update_attributes(struct inode *inode, struct kstat *stat,
+                          struct file *file, bool *refreshed)
+{
+       struct fuse_inode *fi = get_fuse_inode(inode);
+       int err;
+       bool r;
+
+       if (fi->i_time < get_jiffies_64()) {
+               r = true;
+               err = fuse_do_getattr(inode, stat, file);
+       } else {
+               r = false;
+               err = 0;
+               if (stat) {
+                       generic_fillattr(inode, stat);
+                       stat->mode = fi->orig_i_mode;
+               }
+       }
+
+       if (refreshed != NULL)
+               *refreshed = r;
+
+       return err;
+}
+
 /*
  * Calling into a user-controlled filesystem gives the filesystem
  * daemon ptrace-like capabilities over the requester process.  This
@@ -844,18 +941,13 @@ static int fuse_permission(struct inode *inode, int mask, struct nameidata *nd)
         */
        if ((fc->flags & FUSE_DEFAULT_PERMISSIONS) ||
            ((mask & MAY_EXEC) && S_ISREG(inode->i_mode))) {
-               struct fuse_inode *fi = get_fuse_inode(inode);
-               if (fi->i_time < get_jiffies_64()) {
-                       err = fuse_do_getattr(inode, NULL, NULL);
-                       if (err)
-                               return err;
-
-                       refreshed = true;
-               }
+               err = fuse_update_attributes(inode, NULL, NULL, &refreshed);
+               if (err)
+                       return err;
        }
 
        if (fc->flags & FUSE_DEFAULT_PERMISSIONS) {
-               int err = generic_permission(inode, mask, NULL);
+               err = generic_permission(inode, mask, NULL);
 
                /* If permission is denied, try to refresh file
                   attributes.  This is also needed, because the root
@@ -917,7 +1009,6 @@ static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir)
        struct page *page;
        struct inode *inode = file->f_path.dentry->d_inode;
        struct fuse_conn *fc = get_fuse_conn(inode);
-       struct fuse_file *ff = file->private_data;
        struct fuse_req *req;
 
        if (is_bad_inode(inode))
@@ -934,7 +1025,7 @@ static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir)
        }
        req->num_pages = 1;
        req->pages[0] = page;
-       fuse_read_fill(req, ff, inode, file->f_pos, PAGE_SIZE, FUSE_READDIR);
+       fuse_read_fill(req, file, inode, file->f_pos, PAGE_SIZE, FUSE_READDIR);
        request_send(fc, req);
        nbytes = req->out.args[0].size;
        err = req->out.h.error;
@@ -956,7 +1047,7 @@ static char *read_link(struct dentry *dentry)
        char *link;
 
        if (IS_ERR(req))
-               return ERR_PTR(PTR_ERR(req));
+               return ERR_CAST(req);
 
        link = (char *) __get_free_page(GFP_KERNEL);
        if (!link) {
@@ -1056,6 +1147,50 @@ static void iattr_to_fattr(struct iattr *iattr, struct fuse_setattr_in *arg)
        }
 }
 
+/*
+ * Prevent concurrent writepages on inode
+ *
+ * This is done by adding a negative bias to the inode write counter
+ * and waiting for all pending writes to finish.
+ */
+void fuse_set_nowrite(struct inode *inode)
+{
+       struct fuse_conn *fc = get_fuse_conn(inode);
+       struct fuse_inode *fi = get_fuse_inode(inode);
+
+       BUG_ON(!mutex_is_locked(&inode->i_mutex));
+
+       spin_lock(&fc->lock);
+       BUG_ON(fi->writectr < 0);
+       fi->writectr += FUSE_NOWRITE;
+       spin_unlock(&fc->lock);
+       wait_event(fi->page_waitq, fi->writectr == FUSE_NOWRITE);
+}
+
+/*
+ * Allow writepages on inode
+ *
+ * Remove the bias from the writecounter and send any queued
+ * writepages.
+ */
+static void __fuse_release_nowrite(struct inode *inode)
+{
+       struct fuse_inode *fi = get_fuse_inode(inode);
+
+       BUG_ON(fi->writectr != FUSE_NOWRITE);
+       fi->writectr = 0;
+       fuse_flush_writepages(inode);
+}
+
+void fuse_release_nowrite(struct inode *inode)
+{
+       struct fuse_conn *fc = get_fuse_conn(inode);
+
+       spin_lock(&fc->lock);
+       __fuse_release_nowrite(inode);
+       spin_unlock(&fc->lock);
+}
+
 /*
  * Set attributes, and at the same time refresh them.
  *
@@ -1072,6 +1207,8 @@ static int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
        struct fuse_req *req;
        struct fuse_setattr_in inarg;
        struct fuse_attr_out outarg;
+       bool is_truncate = false;
+       loff_t oldsize;
        int err;
 
        if (!fuse_allow_task(fc, current))
@@ -1095,26 +1232,39 @@ static int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
                        send_sig(SIGXFSZ, current, 0);
                        return -EFBIG;
                }
+               is_truncate = true;
        }
 
        req = fuse_get_req(fc);
        if (IS_ERR(req))
                return PTR_ERR(req);
 
+       if (is_truncate)
+               fuse_set_nowrite(inode);
+
        memset(&inarg, 0, sizeof(inarg));
+       memset(&outarg, 0, sizeof(outarg));
        iattr_to_fattr(attr, &inarg);
        if (file) {
                struct fuse_file *ff = file->private_data;
                inarg.valid |= FATTR_FH;
                inarg.fh = ff->fh;
        }
+       if (attr->ia_valid & ATTR_SIZE) {
+               /* For mandatory locking in truncate */
+               inarg.valid |= FATTR_LOCKOWNER;
+               inarg.lock_owner = fuse_lock_owner_id(fc, current->files);
+       }
        req->in.h.opcode = FUSE_SETATTR;
        req->in.h.nodeid = get_node_id(inode);
        req->in.numargs = 1;
        req->in.args[0].size = sizeof(inarg);
        req->in.args[0].value = &inarg;
        req->out.numargs = 1;
-       req->out.args[0].size = sizeof(outarg);
+       if (fc->minor < 9)
+               req->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
+       else
+               req->out.args[0].size = sizeof(outarg);
        req->out.args[0].value = &outarg;
        request_send(fc, req);
        err = req->out.h.error;
@@ -1122,16 +1272,44 @@ static int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
        if (err) {
                if (err == -EINTR)
                        fuse_invalidate_attr(inode);
-               return err;
+               goto error;
        }
 
        if ((inode->i_mode ^ outarg.attr.mode) & S_IFMT) {
                make_bad_inode(inode);
-               return -EIO;
+               err = -EIO;
+               goto error;
+       }
+
+       spin_lock(&fc->lock);
+       fuse_change_attributes_common(inode, &outarg.attr,
+                                     attr_timeout(&outarg));
+       oldsize = inode->i_size;
+       i_size_write(inode, outarg.attr.size);
+
+       if (is_truncate) {
+               /* NOTE: this may release/reacquire fc->lock */
+               __fuse_release_nowrite(inode);
+       }
+       spin_unlock(&fc->lock);
+
+       /*
+        * Only call invalidate_inode_pages2() after removing
+        * FUSE_NOWRITE, otherwise fuse_launder_page() would deadlock.
+        */
+       if (S_ISREG(inode->i_mode) && oldsize != outarg.attr.size) {
+               if (outarg.attr.size < oldsize)
+                       fuse_truncate(inode->i_mapping, outarg.attr.size);
+               invalidate_inode_pages2(inode->i_mapping);
        }
 
-       fuse_change_attributes(inode, &outarg.attr, attr_timeout(&outarg), 0);
        return 0;
+
+error:
+       if (is_truncate)
+               fuse_release_nowrite(inode);
+
+       return err;
 }
 
 static int fuse_setattr(struct dentry *entry, struct iattr *attr)
@@ -1146,22 +1324,12 @@ static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry,
                        struct kstat *stat)
 {
        struct inode *inode = entry->d_inode;
-       struct fuse_inode *fi = get_fuse_inode(inode);
        struct fuse_conn *fc = get_fuse_conn(inode);
-       int err;
 
        if (!fuse_allow_task(fc, current))
                return -EACCES;
 
-       if (fi->i_time < get_jiffies_64())
-               err = fuse_do_getattr(inode, stat, NULL);
-       else {
-               err = 0;
-               generic_fillattr(inode, stat);
-               stat->mode = fi->orig_i_mode;
-       }
-
-       return err;
+       return fuse_update_attributes(inode, stat, NULL, NULL);
 }
 
 static int fuse_setxattr(struct dentry *entry, const char *name,