cifs: don't pass superblock to cifs_mount()

To close sget() races we'll need to be able to set cifs_sb up before
we get the superblock, so we'll want to be able to do cifs_mount()
earlier.  Fortunately, it's easy to do - setting ->s_maxbytes can
be done in cifs_read_super(), ditto for ->s_time_gran and as for
putting MS_POSIXACL into ->s_flags, we can mirror it in ->mnt_cifs_flags
until cifs_read_super() is called.  Kill unused 'devname' argument,
while we are at it...

Acked-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
index ffb1459..7260e11 100644 (file)
--- a/fs/cifs/cifs_fs_sb.h
+++ b/fs/cifs/cifs_fs_sb.h
@@ -42,6 +42,7 @@
 #define CIFS_MOUNT_MULTIUSER   0x20000 /* multiuser mount */
 #define CIFS_MOUNT_STRICT_IO   0x40000 /* strict cache mode */
 #define CIFS_MOUNT_RWPIDFORWARD        0x80000 /* use pid forwarding for rw */
+#define CIFS_MOUNT_POSIXACL    0x100000 /* mirror of MS_POSIXACL in mnt_cifs_flags */
 
 struct cifs_sb_info {
        struct rb_root tlink_tree;

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index bfab2bc..8f7451f 100644 (file)
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -116,7 +116,7 @@ cifs_read_super(struct super_block *sb, struct smb_vol *volume_info,
        spin_lock_init(&cifs_sb->tlink_tree_lock);
        cifs_sb->tlink_tree = RB_ROOT;
 
-       rc = cifs_mount(sb, cifs_sb, volume_info, devname);
+       rc = cifs_mount(cifs_sb, volume_info);
 
        if (rc) {
                if (!silent)
@@ -124,6 +124,17 @@ cifs_read_super(struct super_block *sb, struct smb_vol *volume_info,
                return rc;
        }
 
+       if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIXACL)
+               sb->s_flags |= MS_POSIXACL;
+
+       if (cifs_sb_master_tcon(cifs_sb)->ses->capabilities & CAP_LARGE_FILES)
+               sb->s_maxbytes = MAX_LFS_FILESIZE;
+       else
+               sb->s_maxbytes = MAX_NON_LFS;
+
+       /* BB FIXME fix time_gran to be larger for LANMAN sessions */
+       sb->s_time_gran = 100;
+
        sb->s_magic = CIFS_MAGIC_NUMBER;
        sb->s_op = &cifs_super_ops;
        sb->s_bdi = &cifs_sb->bdi;

diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 953f844..5814fe5 100644 (file)
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -157,8 +157,7 @@ extern int cifs_match_super(struct super_block *, void *);
 extern void cifs_cleanup_volume_info(struct smb_vol **pvolume_info);
 extern int cifs_setup_volume_info(struct smb_vol **pvolume_info,
                                  char *mount_data, const char *devname);
-extern int cifs_mount(struct super_block *, struct cifs_sb_info *,
-                     struct smb_vol *, const char *);
+extern int cifs_mount(struct cifs_sb_info *, struct smb_vol *);
 extern int cifs_umount(struct super_block *, struct cifs_sb_info *);
 extern void cifs_dfs_release_automount_timer(void);
 void cifs_proc_init(void);
@@ -218,7 +217,8 @@ extern int get_dfs_path(int xid, struct cifs_ses *pSesInfo,
                        struct dfs_info3_param **preferrals,
                        int remap);
 extern void reset_cifs_unix_caps(int xid, struct cifs_tcon *tcon,
-                                struct super_block *sb, struct smb_vol *vol);
+                                struct cifs_sb_info *cifs_sb,
+                                struct smb_vol *vol);
 extern int CIFSSMBQFSInfo(const int xid, struct cifs_tcon *tcon,
                        struct kstatfs *FSData);
 extern int SMBOldQFSInfo(const int xid, struct cifs_tcon *tcon,

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 78fd755..3011ac8 100644 (file)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -2546,7 +2546,7 @@ ip_connect(struct TCP_Server_Info *server)
 }
 
 void reset_cifs_unix_caps(int xid, struct cifs_tcon *tcon,
-                         struct super_block *sb, struct smb_vol *vol_info)
+                         struct cifs_sb_info *cifs_sb, struct smb_vol *vol_info)
 {
        /* if we are reconnecting then should we check to see if
         * any requested capabilities changed locally e.g. via
@@ -2600,22 +2600,23 @@ void reset_cifs_unix_caps(int xid, struct cifs_tcon *tcon,
                        cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
                else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
                        cFYI(1, "negotiated posix acl support");
-                       if (sb)
-                               sb->s_flags |= MS_POSIXACL;
+                       if (cifs_sb)
+                               cifs_sb->mnt_cifs_flags |=
+                                       CIFS_MOUNT_POSIXACL;
                }
 
                if (vol_info && vol_info->posix_paths == 0)
                        cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
                else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
                        cFYI(1, "negotiate posix pathnames");
-                       if (sb)
-                               CIFS_SB(sb)->mnt_cifs_flags |=
+                       if (cifs_sb)
+                               cifs_sb->mnt_cifs_flags |=
                                        CIFS_MOUNT_POSIX_PATHS;
                }
 
-               if (sb && (CIFS_SB(sb)->rsize > 127 * 1024)) {
+               if (cifs_sb && (cifs_sb->rsize > 127 * 1024)) {
                        if ((cap & CIFS_UNIX_LARGE_READ_CAP) == 0) {
-                               CIFS_SB(sb)->rsize = 127 * 1024;
+                               cifs_sb->rsize = 127 * 1024;
                                cFYI(DBG2, "larger reads not supported by srv");
                        }
                }
@@ -2971,8 +2972,7 @@ out:
 }
 
 int
-cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
-          struct smb_vol *volume_info, const char *devname)
+cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *volume_info)
 {
        int rc = 0;
        int xid;
@@ -3026,14 +3026,6 @@ try_mount_again:
                goto mount_fail_check;
        }
 
-       if (pSesInfo->capabilities & CAP_LARGE_FILES)
-               sb->s_maxbytes = MAX_LFS_FILESIZE;
-       else
-               sb->s_maxbytes = MAX_NON_LFS;
-
-       /* BB FIXME fix time_gran to be larger for LANMAN sessions */
-       sb->s_time_gran = 100;
-
        /* search for existing tcon to this server share */
        tcon = cifs_get_tcon(pSesInfo, volume_info);
        if (IS_ERR(tcon)) {
@@ -3046,7 +3038,7 @@ try_mount_again:
        if (tcon->ses->capabilities & CAP_UNIX) {
                /* reset of caps checks mount to see if unix extensions
                   disabled for just this mount */
-               reset_cifs_unix_caps(xid, tcon, sb, volume_info);
+               reset_cifs_unix_caps(xid, tcon, cifs_sb, volume_info);
                if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
                    (le64_to_cpu(tcon->fsUnixInfo.Capability) &
                     CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)) {