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Diffstat (limited to 'fs/fuse/dir.c')
-rw-r--r--fs/fuse/dir.c259
1 files changed, 221 insertions, 38 deletions
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index b7c09f9eb40c..85065221a58a 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -14,6 +14,29 @@
#include <linux/namei.h>
#include <linux/slab.h>
+static bool fuse_use_readdirplus(struct inode *dir, struct file *filp)
+{
+ struct fuse_conn *fc = get_fuse_conn(dir);
+ struct fuse_inode *fi = get_fuse_inode(dir);
+
+ if (!fc->do_readdirplus)
+ return false;
+ if (!fc->readdirplus_auto)
+ return true;
+ if (test_and_clear_bit(FUSE_I_ADVISE_RDPLUS, &fi->state))
+ return true;
+ if (filp->f_pos == 0)
+ return true;
+ return false;
+}
+
+static void fuse_advise_use_readdirplus(struct inode *dir)
+{
+ struct fuse_inode *fi = get_fuse_inode(dir);
+
+ set_bit(FUSE_I_ADVISE_RDPLUS, &fi->state);
+}
+
#if BITS_PER_LONG >= 64
static inline void fuse_dentry_settime(struct dentry *entry, u64 time)
{
@@ -178,7 +201,7 @@ static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags)
return -ECHILD;
fc = get_fuse_conn(inode);
- req = fuse_get_req(fc);
+ req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return 0;
@@ -219,6 +242,7 @@ static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags)
attr_version);
fuse_change_entry_timeout(entry, &outarg);
}
+ fuse_advise_use_readdirplus(inode);
return 1;
}
@@ -271,7 +295,7 @@ int fuse_lookup_name(struct super_block *sb, u64 nodeid, struct qstr *name,
if (name->len > FUSE_NAME_MAX)
goto out;
- req = fuse_get_req(fc);
+ req = fuse_get_req_nopages(fc);
err = PTR_ERR(req);
if (IS_ERR(req))
goto out;
@@ -355,6 +379,7 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
else
fuse_invalidate_entry_cache(entry);
+ fuse_advise_use_readdirplus(dir);
return newent;
out_iput:
@@ -391,7 +416,7 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry,
if (!forget)
goto out_err;
- req = fuse_get_req(fc);
+ req = fuse_get_req_nopages(fc);
err = PTR_ERR(req);
if (IS_ERR(req))
goto out_put_forget_req;
@@ -592,7 +617,7 @@ static int fuse_mknod(struct inode *dir, struct dentry *entry, umode_t mode,
{
struct fuse_mknod_in inarg;
struct fuse_conn *fc = get_fuse_conn(dir);
- struct fuse_req *req = fuse_get_req(fc);
+ struct fuse_req *req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -623,7 +648,7 @@ static int fuse_mkdir(struct inode *dir, struct dentry *entry, umode_t mode)
{
struct fuse_mkdir_in inarg;
struct fuse_conn *fc = get_fuse_conn(dir);
- struct fuse_req *req = fuse_get_req(fc);
+ struct fuse_req *req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -647,7 +672,7 @@ static int fuse_symlink(struct inode *dir, struct dentry *entry,
{
struct fuse_conn *fc = get_fuse_conn(dir);
unsigned len = strlen(link) + 1;
- struct fuse_req *req = fuse_get_req(fc);
+ struct fuse_req *req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -664,7 +689,7 @@ static int fuse_unlink(struct inode *dir, struct dentry *entry)
{
int err;
struct fuse_conn *fc = get_fuse_conn(dir);
- struct fuse_req *req = fuse_get_req(fc);
+ struct fuse_req *req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -682,7 +707,14 @@ static int fuse_unlink(struct inode *dir, struct dentry *entry)
spin_lock(&fc->lock);
fi->attr_version = ++fc->attr_version;
- drop_nlink(inode);
+ /*
+ * If i_nlink == 0 then unlink doesn't make sense, yet this can
+ * happen if userspace filesystem is careless. It would be
+ * difficult to enforce correct nlink usage so just ignore this
+ * condition here
+ */
+ if (inode->i_nlink > 0)
+ drop_nlink(inode);
spin_unlock(&fc->lock);
fuse_invalidate_attr(inode);
fuse_invalidate_attr(dir);
@@ -696,7 +728,7 @@ static int fuse_rmdir(struct inode *dir, struct dentry *entry)
{
int err;
struct fuse_conn *fc = get_fuse_conn(dir);
- struct fuse_req *req = fuse_get_req(fc);
+ struct fuse_req *req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -723,7 +755,7 @@ static int fuse_rename(struct inode *olddir, struct dentry *oldent,
int err;
struct fuse_rename_in inarg;
struct fuse_conn *fc = get_fuse_conn(olddir);
- struct fuse_req *req = fuse_get_req(fc);
+ struct fuse_req *req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -776,7 +808,7 @@ static int fuse_link(struct dentry *entry, struct inode *newdir,
struct fuse_link_in inarg;
struct inode *inode = entry->d_inode;
struct fuse_conn *fc = get_fuse_conn(inode);
- struct fuse_req *req = fuse_get_req(fc);
+ struct fuse_req *req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -848,7 +880,7 @@ static int fuse_do_getattr(struct inode *inode, struct kstat *stat,
struct fuse_req *req;
u64 attr_version;
- req = fuse_get_req(fc);
+ req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -985,7 +1017,7 @@ int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
/*
* Calling into a user-controlled filesystem gives the filesystem
- * daemon ptrace-like capabilities over the requester process. This
+ * daemon ptrace-like capabilities over the current process. This
* means, that the filesystem daemon is able to record the exact
* filesystem operations performed, and can also control the behavior
* of the requester process in otherwise impossible ways. For example
@@ -996,27 +1028,23 @@ int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
* for which the owner of the mount has ptrace privilege. This
* excludes processes started by other users, suid or sgid processes.
*/
-int fuse_allow_task(struct fuse_conn *fc, struct task_struct *task)
+int fuse_allow_current_process(struct fuse_conn *fc)
{
const struct cred *cred;
- int ret;
if (fc->flags & FUSE_ALLOW_OTHER)
return 1;
- rcu_read_lock();
- ret = 0;
- cred = __task_cred(task);
+ cred = current_cred();
if (uid_eq(cred->euid, fc->user_id) &&
uid_eq(cred->suid, fc->user_id) &&
uid_eq(cred->uid, fc->user_id) &&
gid_eq(cred->egid, fc->group_id) &&
gid_eq(cred->sgid, fc->group_id) &&
gid_eq(cred->gid, fc->group_id))
- ret = 1;
- rcu_read_unlock();
+ return 1;
- return ret;
+ return 0;
}
static int fuse_access(struct inode *inode, int mask)
@@ -1029,7 +1057,7 @@ static int fuse_access(struct inode *inode, int mask)
if (fc->no_access)
return 0;
- req = fuse_get_req(fc);
+ req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -1077,7 +1105,7 @@ static int fuse_permission(struct inode *inode, int mask)
bool refreshed = false;
int err = 0;
- if (!fuse_allow_task(fc, current))
+ if (!fuse_allow_current_process(fc))
return -EACCES;
/*
@@ -1155,19 +1183,157 @@ static int parse_dirfile(char *buf, size_t nbytes, struct file *file,
return 0;
}
-static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir)
+static int fuse_direntplus_link(struct file *file,
+ struct fuse_direntplus *direntplus,
+ u64 attr_version)
{
int err;
+ struct fuse_entry_out *o = &direntplus->entry_out;
+ struct fuse_dirent *dirent = &direntplus->dirent;
+ struct dentry *parent = file->f_path.dentry;
+ struct qstr name = QSTR_INIT(dirent->name, dirent->namelen);
+ struct dentry *dentry;
+ struct dentry *alias;
+ struct inode *dir = parent->d_inode;
+ struct fuse_conn *fc;
+ struct inode *inode;
+
+ if (!o->nodeid) {
+ /*
+ * Unlike in the case of fuse_lookup, zero nodeid does not mean
+ * ENOENT. Instead, it only means the userspace filesystem did
+ * not want to return attributes/handle for this entry.
+ *
+ * So do nothing.
+ */
+ return 0;
+ }
+
+ if (name.name[0] == '.') {
+ /*
+ * We could potentially refresh the attributes of the directory
+ * and its parent?
+ */
+ if (name.len == 1)
+ return 0;
+ if (name.name[1] == '.' && name.len == 2)
+ return 0;
+ }
+ fc = get_fuse_conn(dir);
+
+ name.hash = full_name_hash(name.name, name.len);
+ dentry = d_lookup(parent, &name);
+ if (dentry && dentry->d_inode) {
+ inode = dentry->d_inode;
+ if (get_node_id(inode) == o->nodeid) {
+ struct fuse_inode *fi;
+ fi = get_fuse_inode(inode);
+ spin_lock(&fc->lock);
+ fi->nlookup++;
+ spin_unlock(&fc->lock);
+
+ /*
+ * The other branch to 'found' comes via fuse_iget()
+ * which bumps nlookup inside
+ */
+ goto found;
+ }
+ err = d_invalidate(dentry);
+ if (err)
+ goto out;
+ dput(dentry);
+ dentry = NULL;
+ }
+
+ dentry = d_alloc(parent, &name);
+ err = -ENOMEM;
+ if (!dentry)
+ goto out;
+
+ inode = fuse_iget(dir->i_sb, o->nodeid, o->generation,
+ &o->attr, entry_attr_timeout(o), attr_version);
+ if (!inode)
+ goto out;
+
+ alias = d_materialise_unique(dentry, inode);
+ err = PTR_ERR(alias);
+ if (IS_ERR(alias))
+ goto out;
+ if (alias) {
+ dput(dentry);
+ dentry = alias;
+ }
+
+found:
+ fuse_change_attributes(inode, &o->attr, entry_attr_timeout(o),
+ attr_version);
+
+ fuse_change_entry_timeout(dentry, o);
+
+ err = 0;
+out:
+ if (dentry)
+ dput(dentry);
+ return err;
+}
+
+static int parse_dirplusfile(char *buf, size_t nbytes, struct file *file,
+ void *dstbuf, filldir_t filldir, u64 attr_version)
+{
+ struct fuse_direntplus *direntplus;
+ struct fuse_dirent *dirent;
+ size_t reclen;
+ int over = 0;
+ int ret;
+
+ while (nbytes >= FUSE_NAME_OFFSET_DIRENTPLUS) {
+ direntplus = (struct fuse_direntplus *) buf;
+ dirent = &direntplus->dirent;
+ reclen = FUSE_DIRENTPLUS_SIZE(direntplus);
+
+ if (!dirent->namelen || dirent->namelen > FUSE_NAME_MAX)
+ return -EIO;
+ if (reclen > nbytes)
+ break;
+
+ if (!over) {
+ /* We fill entries into dstbuf only as much as
+ it can hold. But we still continue iterating
+ over remaining entries to link them. If not,
+ we need to send a FORGET for each of those
+ which we did not link.
+ */
+ over = filldir(dstbuf, dirent->name, dirent->namelen,
+ file->f_pos, dirent->ino,
+ dirent->type);
+ file->f_pos = dirent->off;
+ }
+
+ buf += reclen;
+ nbytes -= reclen;
+
+ ret = fuse_direntplus_link(file, direntplus, attr_version);
+ if (ret)
+ fuse_force_forget(file, direntplus->entry_out.nodeid);
+ }
+
+ return 0;
+}
+
+static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir)
+{
+ int plus, err;
size_t nbytes;
struct page *page;
struct inode *inode = file->f_path.dentry->d_inode;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_req *req;
+ u64 attr_version = 0;
if (is_bad_inode(inode))
return -EIO;
- req = fuse_get_req(fc);
+ req = fuse_get_req(fc, 1);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -1176,17 +1342,34 @@ static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir)
fuse_put_request(fc, req);
return -ENOMEM;
}
+
+ plus = fuse_use_readdirplus(inode, file);
req->out.argpages = 1;
req->num_pages = 1;
req->pages[0] = page;
- fuse_read_fill(req, file, file->f_pos, PAGE_SIZE, FUSE_READDIR);
+ req->page_descs[0].length = PAGE_SIZE;
+ if (plus) {
+ attr_version = fuse_get_attr_version(fc);
+ fuse_read_fill(req, file, file->f_pos, PAGE_SIZE,
+ FUSE_READDIRPLUS);
+ } else {
+ fuse_read_fill(req, file, file->f_pos, PAGE_SIZE,
+ FUSE_READDIR);
+ }
fuse_request_send(fc, req);
nbytes = req->out.args[0].size;
err = req->out.h.error;
fuse_put_request(fc, req);
- if (!err)
- err = parse_dirfile(page_address(page), nbytes, file, dstbuf,
- filldir);
+ if (!err) {
+ if (plus) {
+ err = parse_dirplusfile(page_address(page), nbytes,
+ file, dstbuf, filldir,
+ attr_version);
+ } else {
+ err = parse_dirfile(page_address(page), nbytes, file,
+ dstbuf, filldir);
+ }
+ }
__free_page(page);
fuse_invalidate_attr(inode); /* atime changed */
@@ -1197,7 +1380,7 @@ static char *read_link(struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
struct fuse_conn *fc = get_fuse_conn(inode);
- struct fuse_req *req = fuse_get_req(fc);
+ struct fuse_req *req = fuse_get_req_nopages(fc);
char *link;
if (IS_ERR(req))
@@ -1391,7 +1574,7 @@ static int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
loff_t oldsize;
int err;
- if (!fuse_allow_task(fc, current))
+ if (!fuse_allow_current_process(fc))
return -EACCES;
if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS))
@@ -1410,7 +1593,7 @@ static int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
if (attr->ia_valid & ATTR_SIZE)
is_truncate = true;
- req = fuse_get_req(fc);
+ req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -1500,7 +1683,7 @@ static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry,
struct inode *inode = entry->d_inode;
struct fuse_conn *fc = get_fuse_conn(inode);
- if (!fuse_allow_task(fc, current))
+ if (!fuse_allow_current_process(fc))
return -EACCES;
return fuse_update_attributes(inode, stat, NULL, NULL);
@@ -1518,7 +1701,7 @@ static int fuse_setxattr(struct dentry *entry, const char *name,
if (fc->no_setxattr)
return -EOPNOTSUPP;
- req = fuse_get_req(fc);
+ req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -1557,7 +1740,7 @@ static ssize_t fuse_getxattr(struct dentry *entry, const char *name,
if (fc->no_getxattr)
return -EOPNOTSUPP;
- req = fuse_get_req(fc);
+ req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -1603,13 +1786,13 @@ static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size)
struct fuse_getxattr_out outarg;
ssize_t ret;
- if (!fuse_allow_task(fc, current))
+ if (!fuse_allow_current_process(fc))
return -EACCES;
if (fc->no_listxattr)
return -EOPNOTSUPP;
- req = fuse_get_req(fc);
+ req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);
@@ -1654,7 +1837,7 @@ static int fuse_removexattr(struct dentry *entry, const char *name)
if (fc->no_removexattr)
return -EOPNOTSUPP;
- req = fuse_get_req(fc);
+ req = fuse_get_req_nopages(fc);
if (IS_ERR(req))
return PTR_ERR(req);