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author | David Howells <dhowells@redhat.com> | 2011-01-14 18:45:47 +0000 |
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committer | Al Viro <viro@zeniv.linux.org.uk> | 2011-01-15 20:07:35 -0500 |
commit | 01c64feac45cea1317263eabc4f7ee1b240f297f (patch) | |
tree | b1df5409132ef04e380104a6617d2781f8e196f0 /fs/cifs/cifs_dfs_ref.c | |
parent | 36d43a43761b004ad1879ac21471d8fc5f3157ec (diff) | |
download | linux-stable-01c64feac45cea1317263eabc4f7ee1b240f297f.tar.gz linux-stable-01c64feac45cea1317263eabc4f7ee1b240f297f.tar.bz2 linux-stable-01c64feac45cea1317263eabc4f7ee1b240f297f.zip |
CIFS: Use d_automount() rather than abusing follow_link()
Make CIFS use the new d_automount() dentry operation rather than abusing
follow_link() on directories.
[NOTE: THIS IS UNTESTED!]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Steve French <sfrench@samba.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/cifs/cifs_dfs_ref.c')
-rw-r--r-- | fs/cifs/cifs_dfs_ref.c | 131 |
1 files changed, 67 insertions, 64 deletions
diff --git a/fs/cifs/cifs_dfs_ref.c b/fs/cifs/cifs_dfs_ref.c index 83479cf63f96..0fc163808de3 100644 --- a/fs/cifs/cifs_dfs_ref.c +++ b/fs/cifs/cifs_dfs_ref.c @@ -255,32 +255,6 @@ static struct vfsmount *cifs_dfs_do_refmount(struct cifs_sb_info *cifs_sb, } -static int add_mount_helper(struct vfsmount *newmnt, struct nameidata *nd, - struct list_head *mntlist) -{ - /* stolen from afs code */ - int err; - - mntget(newmnt); - err = do_add_mount(newmnt, &nd->path, nd->path.mnt->mnt_flags | MNT_SHRINKABLE, mntlist); - switch (err) { - case 0: - path_put(&nd->path); - nd->path.mnt = newmnt; - nd->path.dentry = dget(newmnt->mnt_root); - schedule_delayed_work(&cifs_dfs_automount_task, - cifs_dfs_mountpoint_expiry_timeout); - break; - case -EBUSY: - /* someone else made a mount here whilst we were busy */ - err = follow_down(&nd->path, false); - default: - mntput(newmnt); - break; - } - return err; -} - static void dump_referral(const struct dfs_info3_param *ref) { cFYI(1, "DFS: ref path: %s", ref->path_name); @@ -290,45 +264,43 @@ static void dump_referral(const struct dfs_info3_param *ref) ref->path_consumed); } - -static void* -cifs_dfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd) +/* + * Create a vfsmount that we can automount + */ +static struct vfsmount *cifs_dfs_do_automount(struct dentry *mntpt) { struct dfs_info3_param *referrals = NULL; unsigned int num_referrals = 0; struct cifs_sb_info *cifs_sb; struct cifsSesInfo *ses; - char *full_path = NULL; + char *full_path; int xid, i; - int rc = 0; - struct vfsmount *mnt = ERR_PTR(-ENOENT); + int rc; + struct vfsmount *mnt; struct tcon_link *tlink; cFYI(1, "in %s", __func__); - BUG_ON(IS_ROOT(dentry)); + BUG_ON(IS_ROOT(mntpt)); xid = GetXid(); - dput(nd->path.dentry); - nd->path.dentry = dget(dentry); - /* * The MSDFS spec states that paths in DFS referral requests and * responses must be prefixed by a single '\' character instead of * the double backslashes usually used in the UNC. This function * gives us the latter, so we must adjust the result. */ - full_path = build_path_from_dentry(dentry); - if (full_path == NULL) { - rc = -ENOMEM; - goto out_err; - } + mnt = ERR_PTR(-ENOMEM); + full_path = build_path_from_dentry(mntpt); + if (full_path == NULL) + goto free_xid; - cifs_sb = CIFS_SB(dentry->d_inode->i_sb); + cifs_sb = CIFS_SB(mntpt->d_inode->i_sb); tlink = cifs_sb_tlink(cifs_sb); + mnt = ERR_PTR(-EINVAL); if (IS_ERR(tlink)) { - rc = PTR_ERR(tlink); - goto out_err; + mnt = ERR_CAST(tlink); + goto free_full_path; } ses = tlink_tcon(tlink)->ses; @@ -338,46 +310,77 @@ cifs_dfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd) cifs_put_tlink(tlink); + mnt = ERR_PTR(-ENOENT); for (i = 0; i < num_referrals; i++) { int len; - dump_referral(referrals+i); + dump_referral(referrals + i); /* connect to a node */ len = strlen(referrals[i].node_name); if (len < 2) { cERROR(1, "%s: Net Address path too short: %s", __func__, referrals[i].node_name); - rc = -EINVAL; - goto out_err; + mnt = ERR_PTR(-EINVAL); + break; } mnt = cifs_dfs_do_refmount(cifs_sb, full_path, referrals + i); cFYI(1, "%s: cifs_dfs_do_refmount:%s , mnt:%p", __func__, referrals[i].node_name, mnt); - - /* complete mount procedure if we accured submount */ if (!IS_ERR(mnt)) - break; + goto success; } - /* we need it cause for() above could exit without valid submount */ - rc = PTR_ERR(mnt); - if (IS_ERR(mnt)) - goto out_err; - - rc = add_mount_helper(mnt, nd, &cifs_dfs_automount_list); + /* no valid submounts were found; return error from get_dfs_path() by + * preference */ + if (rc != 0) + mnt = ERR_PTR(rc); -out: - FreeXid(xid); +success: free_dfs_info_array(referrals, num_referrals); +free_full_path: kfree(full_path); +free_xid: + FreeXid(xid); cFYI(1, "leaving %s" , __func__); - return ERR_PTR(rc); -out_err: - path_put(&nd->path); - goto out; + return mnt; +} + +/* + * Attempt to automount the referral + */ +struct vfsmount *cifs_dfs_d_automount(struct path *path) +{ + struct vfsmount *newmnt; + int err; + + cFYI(1, "in %s", __func__); + + newmnt = cifs_dfs_do_automount(path->dentry); + if (IS_ERR(newmnt)) { + cFYI(1, "leaving %s [automount failed]" , __func__); + return newmnt; + } + + mntget(newmnt); + err = do_add_mount(newmnt, path, path->mnt->mnt_flags | MNT_SHRINKABLE, + &cifs_dfs_automount_list); + switch (err) { + case 0: + schedule_delayed_work(&cifs_dfs_automount_task, + cifs_dfs_mountpoint_expiry_timeout); + cFYI(1, "leaving %s [ok]" , __func__); + return newmnt; + case -EBUSY: + /* someone else made a mount here whilst we were busy */ + mntput(newmnt); + cFYI(1, "leaving %s [EBUSY]" , __func__); + return NULL; + default: + mntput(newmnt); + cFYI(1, "leaving %s [error %d]" , __func__, err); + return ERR_PTR(err); + } } const struct inode_operations cifs_dfs_referral_inode_operations = { - .follow_link = cifs_dfs_follow_mountpoint, }; - |