From 680baacbca69d18a6d7315374ad83d05ac9c0977 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 2 May 2015 13:32:22 -0400 Subject: new ->follow_link() and ->put_link() calling conventions a) instead of storing the symlink body (via nd_set_link()) and returning an opaque pointer later passed to ->put_link(), ->follow_link() _stores_ that opaque pointer (into void * passed by address by caller) and returns the symlink body. Returning ERR_PTR() on error, NULL on jump (procfs magic symlinks) and pointer to symlink body for normal symlinks. Stored pointer is ignored in all cases except the last one. Storing NULL for opaque pointer (or not storing it at all) means no call of ->put_link(). b) the body used to be passed to ->put_link() implicitly (via nameidata). Now only the opaque pointer is. In the cases when we used the symlink body to free stuff, ->follow_link() now should store it as opaque pointer in addition to returning it. Signed-off-by: Al Viro --- fs/cifs/cifsfs.h | 2 +- fs/cifs/link.c | 28 +++++++++++++--------------- 2 files changed, 14 insertions(+), 16 deletions(-) (limited to 'fs/cifs') diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h index 252f5c15806b..61012da7e9d8 100644 --- a/fs/cifs/cifsfs.h +++ b/fs/cifs/cifsfs.h @@ -120,7 +120,7 @@ extern struct vfsmount *cifs_dfs_d_automount(struct path *path); #endif /* Functions related to symlinks */ -extern void *cifs_follow_link(struct dentry *direntry, struct nameidata *nd); +extern const char *cifs_follow_link(struct dentry *direntry, void **cookie, struct nameidata *nd); extern int cifs_readlink(struct dentry *direntry, char __user *buffer, int buflen); extern int cifs_symlink(struct inode *inode, struct dentry *direntry, diff --git a/fs/cifs/link.c b/fs/cifs/link.c index 252e672d5604..4a439c2c0c7f 100644 --- a/fs/cifs/link.c +++ b/fs/cifs/link.c @@ -626,8 +626,8 @@ cifs_hl_exit: return rc; } -void * -cifs_follow_link(struct dentry *direntry, struct nameidata *nd) +const char * +cifs_follow_link(struct dentry *direntry, void **cookie, struct nameidata *nd) { struct inode *inode = d_inode(direntry); int rc = -ENOMEM; @@ -643,16 +643,18 @@ cifs_follow_link(struct dentry *direntry, struct nameidata *nd) tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) { - rc = PTR_ERR(tlink); - tlink = NULL; - goto out; + free_xid(xid); + return ERR_CAST(tlink); } tcon = tlink_tcon(tlink); server = tcon->ses->server; full_path = build_path_from_dentry(direntry); - if (!full_path) - goto out; + if (!full_path) { + free_xid(xid); + cifs_put_tlink(tlink); + return ERR_PTR(-ENOMEM); + } cifs_dbg(FYI, "Full path: %s inode = 0x%p\n", full_path, inode); @@ -670,17 +672,13 @@ cifs_follow_link(struct dentry *direntry, struct nameidata *nd) &target_path, cifs_sb); kfree(full_path); -out: + free_xid(xid); + cifs_put_tlink(tlink); if (rc != 0) { kfree(target_path); - target_path = ERR_PTR(rc); + return ERR_PTR(rc); } - - free_xid(xid); - if (tlink) - cifs_put_tlink(tlink); - nd_set_link(nd, target_path); - return NULL; + return *cookie = target_path; } int -- cgit v1.2.3 From 6e77137b363b8d866ac29c5a0c95e953614fb2d8 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 2 May 2015 13:37:52 -0400 Subject: don't pass nameidata to ->follow_link() its only use is getting passed to nd_jump_link(), which can obtain it from current->nameidata Signed-off-by: Al Viro --- fs/cifs/cifsfs.h | 2 +- fs/cifs/link.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/cifs') diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h index 61012da7e9d8..a782b22904e4 100644 --- a/fs/cifs/cifsfs.h +++ b/fs/cifs/cifsfs.h @@ -120,7 +120,7 @@ extern struct vfsmount *cifs_dfs_d_automount(struct path *path); #endif /* Functions related to symlinks */ -extern const char *cifs_follow_link(struct dentry *direntry, void **cookie, struct nameidata *nd); +extern const char *cifs_follow_link(struct dentry *direntry, void **cookie); extern int cifs_readlink(struct dentry *direntry, char __user *buffer, int buflen); extern int cifs_symlink(struct inode *inode, struct dentry *direntry, diff --git a/fs/cifs/link.c b/fs/cifs/link.c index 4a439c2c0c7f..546f86ab09aa 100644 --- a/fs/cifs/link.c +++ b/fs/cifs/link.c @@ -627,7 +627,7 @@ cifs_hl_exit: } const char * -cifs_follow_link(struct dentry *direntry, void **cookie, struct nameidata *nd) +cifs_follow_link(struct dentry *direntry, void **cookie) { struct inode *inode = d_inode(direntry); int rc = -ENOMEM; -- cgit v1.2.3