Collect "operation mode" arguments of do_last() into a structure

No point messing with passing shitloads of "operation mode" arguments
to do_open() one by one, especially since they are not going to change
during do_filp_open().  Collect them into a struct, fill it and pass
to do_last() by reference.

Make sure that lookup intent flags are correctly set and removed - we
want them for do_last(), but they make no sense for __do_follow_link().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/namei.c b/fs/namei.c
index e0f5903..5e4206f 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2169,17 +2169,26 @@ exit:
        return ERR_PTR(error);
 }
 
+struct open_flags {
+       int open_flag;
+       int mode;
+       int acc_mode;
+       int intent;
+};
+
 /*
  * Handle O_CREAT case for do_filp_open
  */
 static struct file *do_last(struct nameidata *nd, struct path *path,
-                           int open_flag, int acc_mode,
-                           int mode, const char *pathname)
+                           const struct open_flags *op, const char *pathname)
 {
        struct dentry *dir = nd->path.dentry;
        struct file *filp;
        int error;
 
+       nd->flags &= ~LOOKUP_PARENT;
+       nd->flags |= op->intent;
+
        switch (nd->last_type) {
        case LAST_DOTDOT:
                follow_dotdot(nd);
@@ -2233,7 +2242,7 @@ static struct file *do_last(struct nameidata *nd, struct path *path,
                error = mnt_want_write(nd->path.mnt);
                if (error)
                        goto exit_mutex_unlock;
-               error = __open_namei_create(nd, path, open_flag, mode);
+               error = __open_namei_create(nd, path, op->open_flag, op->mode);
                if (error) {
                        mnt_drop_write(nd->path.mnt);
                        goto exit;
@@ -2242,7 +2251,7 @@ static struct file *do_last(struct nameidata *nd, struct path *path,
                mnt_drop_write(nd->path.mnt);
                path_put(&nd->path);
                if (!IS_ERR(filp)) {
-                       error = ima_file_check(filp, acc_mode);
+                       error = ima_file_check(filp, op->acc_mode);
                        if (error) {
                                fput(filp);
                                filp = ERR_PTR(error);
@@ -2258,7 +2267,7 @@ static struct file *do_last(struct nameidata *nd, struct path *path,
        audit_inode(pathname, path->dentry);
 
        error = -EEXIST;
-       if (open_flag & O_EXCL)
+       if (op->open_flag & O_EXCL)
                goto exit_dput;
 
        error = follow_managed(path, nd->flags);
@@ -2278,7 +2287,7 @@ static struct file *do_last(struct nameidata *nd, struct path *path,
        if (S_ISDIR(nd->inode->i_mode))
                goto exit;
 ok:
-       filp = finish_open(nd, open_flag, acc_mode);
+       filp = finish_open(nd, op->open_flag, op->acc_mode);
        return filp;
 
 exit_mutex_unlock:
@@ -2304,7 +2313,8 @@ struct file *do_filp_open(int dfd, const char *pathname,
        struct path path;
        int count = 0;
        int flag = open_to_namei_flags(open_flag);
-       int flags;
+       int flags = 0;
+       struct open_flags op;
 
        if (!(open_flag & O_CREAT))
                mode = 0;
@@ -2321,6 +2331,8 @@ struct file *do_filp_open(int dfd, const char *pathname,
        if (open_flag & __O_SYNC)
                open_flag |= O_DSYNC;
 
+       op.open_flag = open_flag;
+
        if (!acc_mode)
                acc_mode = MAY_OPEN | ACC_MODE(open_flag);
 
@@ -2333,12 +2345,15 @@ struct file *do_filp_open(int dfd, const char *pathname,
        if (open_flag & O_APPEND)
                acc_mode |= MAY_APPEND;
 
-       flags = LOOKUP_OPEN;
+       op.acc_mode = acc_mode;
+
+       op.intent = LOOKUP_OPEN;
        if (open_flag & O_CREAT) {
-               flags |= LOOKUP_CREATE;
+               op.intent |= LOOKUP_CREATE;
                if (open_flag & O_EXCL)
-                       flags |= LOOKUP_EXCL;
+                       op.intent |= LOOKUP_EXCL;
        }
+
        if (open_flag & O_DIRECTORY)
                flags |= LOOKUP_DIRECTORY;
        if (!(open_flag & O_NOFOLLOW))
@@ -2357,7 +2372,7 @@ struct file *do_filp_open(int dfd, const char *pathname,
                goto creat;
 
        /* !O_CREAT, simple open */
-       error = do_path_lookup(dfd, pathname, flags, &nd);
+       error = do_path_lookup(dfd, pathname, flags | op.intent, &nd);
        if (unlikely(error))
                goto out_filp2;
        error = -ELOOP;
@@ -2384,14 +2399,14 @@ out_filp2:
 
 creat:
        /* OK, have to create the file. Find the parent. */
-       error = path_lookupat(dfd, pathname, LOOKUP_PARENT | LOOKUP_RCU, &nd);
+       error = path_lookupat(dfd, pathname,
+                       LOOKUP_PARENT | LOOKUP_RCU | flags, &nd);
        if (unlikely(error == -ECHILD))
-               error = path_lookupat(dfd, pathname, LOOKUP_PARENT, &nd);
+               error = path_lookupat(dfd, pathname, LOOKUP_PARENT | flags, &nd);
        if (unlikely(error == -ESTALE)) {
 reval:
                flags |= LOOKUP_REVAL;
-               error = path_lookupat(dfd, pathname,
-                               LOOKUP_PARENT | LOOKUP_REVAL, &nd);
+               error = path_lookupat(dfd, pathname, LOOKUP_PARENT | flags, &nd);
        }
        if (unlikely(error))
                goto out_filp;
@@ -2401,8 +2416,7 @@ reval:
        /*
         * We have the parent and last component.
         */
-       nd.flags = (nd.flags & ~LOOKUP_PARENT) | flags;
-       filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname);
+       filp = do_last(&nd, &path, &op, pathname);
        while (unlikely(!filp)) { /* trailing symlink */
                struct path link = path;
                struct inode *linki = link.dentry->d_inode;
@@ -2424,13 +2438,12 @@ reval:
                 * just set LAST_BIND.
                 */
                nd.flags |= LOOKUP_PARENT;
+               nd.flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL);
                error = __do_follow_link(&link, &nd, &cookie);
-               if (unlikely(error)) {
+               if (unlikely(error))
                        filp = ERR_PTR(error);
-               } else {
-                       nd.flags &= ~LOOKUP_PARENT;
-                       filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname);
-               }
+               else
+                       filp = do_last(&nd, &path, &op, pathname);
                if (!IS_ERR(cookie) && linki->i_op->put_link)
                        linki->i_op->put_link(link.dentry, &nd, cookie);
                path_put(&link);