ceph: implement i_op->atomic_open()

Add an ->atomic_open implementation which replaces the atomic lookup+open+create
operation implemented via ->lookup and ->create operations.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: Sage Weil <sage@newdream.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Miklos Szeredi 2012-06-05 15:10:25 +02:00 committed by Al Viro
parent 3819219b59
commit 2d83bde9a1
3 changed files with 56 additions and 38 deletions

View File

@ -594,14 +594,6 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
if (err < 0)
return ERR_PTR(err);
/* open (but not create!) intent? */
if (nd &&
(nd->flags & LOOKUP_OPEN) &&
!(nd->intent.open.flags & O_CREAT)) {
int mode = nd->intent.open.create_mode & ~current->fs->umask;
return ceph_lookup_open(dir, dentry, nd, mode);
}
/* can we conclude ENOENT locally? */
if (dentry->d_inode == NULL) {
struct ceph_inode_info *ci = ceph_inode(dir);
@ -642,6 +634,47 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
return dentry;
}
struct file *ceph_atomic_open(struct inode *dir, struct dentry *dentry,
struct opendata *od, unsigned flags, umode_t mode,
bool *created)
{
int err;
struct dentry *res = NULL;
struct file *filp;
if (!(flags & O_CREAT)) {
if (dentry->d_name.len > NAME_MAX)
return ERR_PTR(-ENAMETOOLONG);
err = ceph_init_dentry(dentry);
if (err < 0)
return ERR_PTR(err);
return ceph_lookup_open(dir, dentry, od, flags, mode);
}
if (d_unhashed(dentry)) {
res = ceph_lookup(dir, dentry, NULL);
if (IS_ERR(res))
return ERR_CAST(res);
if (res)
dentry = res;
}
/* We don't deal with positive dentries here */
if (dentry->d_inode) {
finish_no_open(od, res);
return NULL;
}
*created = true;
filp = ceph_lookup_open(dir, dentry, od, flags, mode);
dput(res);
return filp;
}
/*
* If we do a create but get no trace back from the MDS, follow up with
* a lookup (the VFS expects us to link up the provided dentry).
@ -702,23 +735,7 @@ static int ceph_mknod(struct inode *dir, struct dentry *dentry,
static int ceph_create(struct inode *dir, struct dentry *dentry, umode_t mode,
struct nameidata *nd)
{
dout("create in dir %p dentry %p name '%.*s'\n",
dir, dentry, dentry->d_name.len, dentry->d_name.name);
if (ceph_snap(dir) != CEPH_NOSNAP)
return -EROFS;
if (nd) {
BUG_ON((nd->flags & LOOKUP_OPEN) == 0);
dentry = ceph_lookup_open(dir, dentry, nd, mode);
/* hrm, what should i do here if we get aliased? */
if (IS_ERR(dentry))
return PTR_ERR(dentry);
return 0;
}
/* fall back to mknod */
return ceph_mknod(dir, dentry, (mode & ~S_IFMT) | S_IFREG, 0);
return ceph_mknod(dir, dentry, mode, 0);
}
static int ceph_symlink(struct inode *dir, struct dentry *dentry,
@ -1357,6 +1374,7 @@ const struct inode_operations ceph_dir_iops = {
.rmdir = ceph_unlink,
.rename = ceph_rename,
.create = ceph_create,
.atomic_open = ceph_atomic_open,
};
const struct dentry_operations ceph_dentry_ops = {

View File

@ -213,21 +213,15 @@ int ceph_open(struct inode *inode, struct file *file)
* may_open() fails, the struct *file gets cleaned up (i.e.
* ceph_release gets called). So fear not!
*/
/*
* flags
* path_lookup_open -> LOOKUP_OPEN
* path_lookup_create -> LOOKUP_OPEN|LOOKUP_CREATE
*/
struct dentry *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
struct nameidata *nd, int mode)
struct file *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
struct opendata *od, unsigned flags, umode_t mode)
{
struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
struct ceph_mds_client *mdsc = fsc->mdsc;
struct file *file;
struct file *file = NULL;
struct ceph_mds_request *req;
struct dentry *ret;
int err;
int flags = nd->intent.open.flags;
dout("ceph_lookup_open dentry %p '%.*s' flags %d mode 0%o\n",
dentry, dentry->d_name.len, dentry->d_name.name, flags, mode);
@ -253,14 +247,19 @@ struct dentry *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
err = ceph_handle_notrace_create(dir, dentry);
if (err)
goto out;
file = lookup_instantiate_filp(nd, req->r_dentry, ceph_open);
file = finish_open(od, req->r_dentry, ceph_open);
if (IS_ERR(file))
err = PTR_ERR(file);
out:
ret = ceph_finish_lookup(req, dentry, err);
ceph_mdsc_put_request(req);
dout("ceph_lookup_open result=%p\n", ret);
return ret;
if (IS_ERR(ret))
return ERR_CAST(ret);
dput(ret);
return err ? ERR_PTR(err) : file;
}
int ceph_release(struct inode *inode, struct file *file)

View File

@ -806,8 +806,9 @@ extern int ceph_copy_from_page_vector(struct page **pages,
loff_t off, size_t len);
extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
extern int ceph_open(struct inode *inode, struct file *file);
extern struct dentry *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
struct nameidata *nd, int mode);
extern struct file *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
struct opendata *od, unsigned flags,
umode_t mode);
extern int ceph_release(struct inode *inode, struct file *filp);
/* dir.c */