[PATCH 1/7] autofs: remove wrong comment

[PATCH 1/7] autofs: remove wrong comment

[Ian Kent]

From: Tomohiro Kusumi <tkusumi@tuxera.com>

This format seems to have been taken from device mapper header,
but autofs has no such file:function in both kernel and userspace.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Ian Kent <raven@themaw.net>
---
 include/uapi/linux/auto_dev-ioctl.h |    4 ----
 1 file changed, 4 deletions(-)

diff --git a/include/uapi/linux/auto_dev-ioctl.h b/include/uapi/linux/auto_dev-ioctl.h
index 021ed33..388739b 100644
--- a/include/uapi/linux/auto_dev-ioctl.h
+++ b/include/uapi/linux/auto_dev-ioctl.h
@@ -120,10 +120,6 @@ static inline void init_autofs_dev_ioctl(struct autofs_dev_ioctl *in)
 	in->ioctlfd = -1;
 }
 
-/*
- * If you change this make sure you make the corresponding change
- * to autofs-dev-ioctl.c:lookup_ioctl()
- */
 enum {
 	/* Get various version info */
 	AUTOFS_DEV_IOCTL_VERSION_CMD = 0x71,

[PATCH 2/7] autofs: fix typo in Documentation

[Ian Kent]

From: Tomohiro Kusumi <tkusumi@tuxera.com>

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Ian Kent <raven@themaw.net>
---
 Documentation/filesystems/autofs4.txt |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/Documentation/filesystems/autofs4.txt b/Documentation/filesystems/autofs4.txt
index 8fac3fe..a5dc56f 100644
--- a/Documentation/filesystems/autofs4.txt
+++ b/Documentation/filesystems/autofs4.txt
@@ -65,7 +65,7 @@ directory is a mount trap only if the filesystem is mounted *direct*
 and the root is empty.
 
 Directories created in the root directory are mount traps only if the
-filesystem is mounted  *indirect* and they are empty.
+filesystem is mounted *indirect* and they are empty.
 
 Directories further down the tree depend on the *maxproto* mount
 option and particularly whether it is less than five or not.
@@ -352,7 +352,7 @@ Communicating with autofs: root directory ioctls
 ------------------------------------------------
 
 The root directory of an autofs filesystem will respond to a number of
-ioctls.   The process issuing the ioctl must have the CAP_SYS_ADMIN
+ioctls.  The process issuing the ioctl must have the CAP_SYS_ADMIN
 capability, or must be the automount daemon.
 
 The available ioctl commands are:
@@ -512,7 +512,7 @@ always be mounted "shared". e.g.
 
 > `mount --make-shared /autofs/mount/point`
 
-The automount daemon is only able to mange a single mount location for
+The automount daemon is only able to manage a single mount location for
 an autofs filesystem and if mounts on that are not 'shared', other
 locations will not behave as expected.  In particular access to those
 other locations will likely result in the `ELOOP` error

[PATCH 3/7] autofs: fix wrong ioctl documentation regarding devid

[Ian Kent]

From: Tomohiro Kusumi <tkusumi@tuxera.com>

This is the same as d8732841 except that it's a different file.
A caller has no devid input, and devid is obtained via superblock.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Ian Kent <raven@themaw.net>
---
 Documentation/filesystems/autofs4.txt |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/Documentation/filesystems/autofs4.txt b/Documentation/filesystems/autofs4.txt
index a5dc56f..7534863 100644
--- a/Documentation/filesystems/autofs4.txt
+++ b/Documentation/filesystems/autofs4.txt
@@ -457,9 +457,8 @@ Commands are:
     daemon.
 - **AUTOFS_DEV_IOCTL_REQUESTER_CMD**: `path` should be a
     name within the filesystem that has been auto-mounted on.
-    arg1 is the dev number of the underlying autofs.  On successful
-    return, `arg1` and `arg2` will be the UID and GID of the process
-    which triggered that mount.
+    On successful return, `arg1` and `arg2` will be the UID and GID
+    of the process which triggered that mount.
 
 - **AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD**: Check if path is a
     mountpoint of a particular type - see separate documentation for

[PATCH 4/7] autofs: update ioctl documentation regarding struct autofs_dev_ioctl

[Ian Kent]

From: Tomohiro Kusumi <tkusumi@tuxera.com>

This is the same as bf72eda5 except that it's a different file.
Sync documentation with changes made by 730c9eec in 2009.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Ian Kent <raven@themaw.net>
---
 .../filesystems/autofs4-mount-control.txt          |    1 +
 Documentation/filesystems/autofs4.txt              |   32 +++++++++++++-------
 2 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/Documentation/filesystems/autofs4-mount-control.txt b/Documentation/filesystems/autofs4-mount-control.txt
index 50a3e01..e5177cb 100644
--- a/Documentation/filesystems/autofs4-mount-control.txt
+++ b/Documentation/filesystems/autofs4-mount-control.txt
@@ -179,6 +179,7 @@ struct autofs_dev_ioctl {
 				 * including this struct */
 	__s32 ioctlfd;          /* automount command fd */
 
+	/* Command parameters */
 	union {
 		struct args_protover		protover;
 		struct args_protosubver		protosubver;
diff --git a/Documentation/filesystems/autofs4.txt b/Documentation/filesystems/autofs4.txt
index 7534863..f10dd59 100644
--- a/Documentation/filesystems/autofs4.txt
+++ b/Documentation/filesystems/autofs4.txt
@@ -425,8 +425,20 @@ Each ioctl is passed a pointer to an `autofs_dev_ioctl` structure:
                                          * including this struct */
                 __s32 ioctlfd;          /* automount command fd */
 
-                __u32 arg1;             /* Command parameters */
-                __u32 arg2;
+		/* Command parameters */
+		union {
+			struct args_protover		protover;
+			struct args_protosubver		protosubver;
+			struct args_openmount		openmount;
+			struct args_ready		ready;
+			struct args_fail		fail;
+			struct args_setpipefd		setpipefd;
+			struct args_timeout		timeout;
+			struct args_requester		requester;
+			struct args_expire		expire;
+			struct args_askumount		askumount;
+			struct args_ismountpoint	ismountpoint;
+		};
 
                 char path[0];
         };
@@ -446,24 +458,22 @@ Commands are:
     set version numbers.
 - **AUTOFS_DEV_IOCTL_OPENMOUNT_CMD**: return an open file descriptor
     on the root of an autofs filesystem.  The filesystem is identified
-    by name and device number, which is stored in `arg1`.  Device
-    numbers for existing filesystems can be found in
+    by name and device number, which is stored in `openmount.devid`.
+    Device numbers for existing filesystems can be found in
     `/proc/self/mountinfo`.
 - **AUTOFS_DEV_IOCTL_CLOSEMOUNT_CMD**: same as `close(ioctlfd)`.
 - **AUTOFS_DEV_IOCTL_SETPIPEFD_CMD**: if the filesystem is in
     catatonic mode, this can provide the write end of a new pipe
-    in `arg1` to re-establish communication with a daemon.  The
-    process group of the calling process is used to identify the
+    in `setpipefd.pipefd` to re-establish communication with a daemon.
+    The process group of the calling process is used to identify the
     daemon.
 - **AUTOFS_DEV_IOCTL_REQUESTER_CMD**: `path` should be a
     name within the filesystem that has been auto-mounted on.
-    On successful return, `arg1` and `arg2` will be the UID and GID
-    of the process which triggered that mount.
-
+    On successful return, `requester.uid` and `requester.gid` will be
+    the UID and GID of the process which triggered that mount.
 - **AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD**: Check if path is a
     mountpoint of a particular type - see separate documentation for
     details.
-
 - **AUTOFS_DEV_IOCTL_PROTOVER_CMD**:
 - **AUTOFS_DEV_IOCTL_PROTOSUBVER_CMD**:
 - **AUTOFS_DEV_IOCTL_READY_CMD**:
@@ -473,7 +483,7 @@ Commands are:
 - **AUTOFS_DEV_IOCTL_EXPIRE_CMD**:
 - **AUTOFS_DEV_IOCTL_ASKUMOUNT_CMD**:  These all have the same
     function as the similarly named **AUTOFS_IOC** ioctls, except
-    that **FAIL** can be given an explicit error number in `arg1`
+    that **FAIL** can be given an explicit error number in `fail.status`
     instead of assuming `ENOENT`, and this **EXPIRE** command
     corresponds to **AUTOFS_IOC_EXPIRE_MULTI**.
 

[PATCH 5/7] autofs: add command enum/macros for root-dir ioctls

[Ian Kent]

From: Tomohiro Kusumi <tkusumi@tuxera.com>

Sync root-dir ioctl with misc-char-dev ioctl's enum/macro format
since these two types of ioctls aren't completely independent of
each other in terms of command nr. No functional changes.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Ian Kent <raven@themaw.net>
---
 include/uapi/linux/auto_dev-ioctl.h |    2 --
 include/uapi/linux/auto_fs.h        |   25 ++++++++++++++++++-------
 include/uapi/linux/auto_fs4.h       |   16 +++++++++++-----
 3 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/include/uapi/linux/auto_dev-ioctl.h b/include/uapi/linux/auto_dev-ioctl.h
index 388739b..af107aa 100644
--- a/include/uapi/linux/auto_dev-ioctl.h
+++ b/include/uapi/linux/auto_dev-ioctl.h
@@ -156,8 +156,6 @@ enum {
 	AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD,
 };
 
-#define AUTOFS_IOCTL 0x93
-
 #define AUTOFS_DEV_IOCTL_VERSION \
 	_IOWR(AUTOFS_IOCTL, \
 	      AUTOFS_DEV_IOCTL_VERSION_CMD, struct autofs_dev_ioctl)
diff --git a/include/uapi/linux/auto_fs.h b/include/uapi/linux/auto_fs.h
index 1bfc3ed..aa63451 100644
--- a/include/uapi/linux/auto_fs.h
+++ b/include/uapi/linux/auto_fs.h
@@ -61,12 +61,23 @@ struct autofs_packet_expire {
 	char name[NAME_MAX+1];
 };
 
-#define AUTOFS_IOC_READY      _IO(0x93, 0x60)
-#define AUTOFS_IOC_FAIL       _IO(0x93, 0x61)
-#define AUTOFS_IOC_CATATONIC  _IO(0x93, 0x62)
-#define AUTOFS_IOC_PROTOVER   _IOR(0x93, 0x63, int)
-#define AUTOFS_IOC_SETTIMEOUT32 _IOWR(0x93, 0x64, compat_ulong_t)
-#define AUTOFS_IOC_SETTIMEOUT _IOWR(0x93, 0x64, unsigned long)
-#define AUTOFS_IOC_EXPIRE     _IOR(0x93, 0x65, struct autofs_packet_expire)
+#define AUTOFS_IOCTL 0x93
+
+enum {
+	AUTOFS_IOC_READY_CMD = 0x60,
+	AUTOFS_IOC_FAIL_CMD,
+	AUTOFS_IOC_CATATONIC_CMD,
+	AUTOFS_IOC_PROTOVER_CMD,
+	AUTOFS_IOC_SETTIMEOUT_CMD,
+	AUTOFS_IOC_EXPIRE_CMD,
+};
+
+#define AUTOFS_IOC_READY        _IO(AUTOFS_IOCTL, AUTOFS_IOC_READY_CMD)
+#define AUTOFS_IOC_FAIL         _IO(AUTOFS_IOCTL, AUTOFS_IOC_FAIL_CMD)
+#define AUTOFS_IOC_CATATONIC    _IO(AUTOFS_IOCTL, AUTOFS_IOC_CATATONIC_CMD)
+#define AUTOFS_IOC_PROTOVER     _IOR(AUTOFS_IOCTL, AUTOFS_IOC_PROTOVER_CMD, int)
+#define AUTOFS_IOC_SETTIMEOUT32 _IOWR(AUTOFS_IOCTL, AUTOFS_IOC_SETTIMEOUT_CMD, compat_ulong_t)
+#define AUTOFS_IOC_SETTIMEOUT   _IOWR(AUTOFS_IOCTL, AUTOFS_IOC_SETTIMEOUT_CMD, unsigned long)
+#define AUTOFS_IOC_EXPIRE       _IOR(AUTOFS_IOCTL, AUTOFS_IOC_EXPIRE_CMD, struct autofs_packet_expire)
 
 #endif /* _UAPI_LINUX_AUTO_FS_H */
diff --git a/include/uapi/linux/auto_fs4.h b/include/uapi/linux/auto_fs4.h
index 8f8f1bd..7c6da42 100644
--- a/include/uapi/linux/auto_fs4.h
+++ b/include/uapi/linux/auto_fs4.h
@@ -148,10 +148,16 @@ union autofs_v5_packet_union {
 	autofs_packet_expire_direct_t expire_direct;
 };
 
-#define AUTOFS_IOC_EXPIRE_MULTI		_IOW(0x93, 0x66, int)
-#define AUTOFS_IOC_EXPIRE_INDIRECT	AUTOFS_IOC_EXPIRE_MULTI
-#define AUTOFS_IOC_EXPIRE_DIRECT	AUTOFS_IOC_EXPIRE_MULTI
-#define AUTOFS_IOC_PROTOSUBVER		_IOR(0x93, 0x67, int)
-#define AUTOFS_IOC_ASKUMOUNT		_IOR(0x93, 0x70, int)
+enum {
+	AUTOFS_IOC_EXPIRE_MULTI_CMD = 0x66, /* AUTOFS_IOC_EXPIRE_CMD + 1 */
+	AUTOFS_IOC_PROTOSUBVER_CMD,
+	AUTOFS_IOC_ASKUMOUNT_CMD = 0x70, /* AUTOFS_DEV_IOCTL_VERSION_CMD - 1 */
+};
+
+#define AUTOFS_IOC_EXPIRE_MULTI    _IOW(AUTOFS_IOCTL, AUTOFS_IOC_EXPIRE_MULTI_CMD, int)
+#define AUTOFS_IOC_EXPIRE_INDIRECT AUTOFS_IOC_EXPIRE_MULTI
+#define AUTOFS_IOC_EXPIRE_DIRECT   AUTOFS_IOC_EXPIRE_MULTI
+#define AUTOFS_IOC_PROTOSUBVER     _IOR(AUTOFS_IOCTL, AUTOFS_IOC_PROTOSUBVER_CMD, int)
+#define AUTOFS_IOC_ASKUMOUNT       _IOR(AUTOFS_IOCTL, AUTOFS_IOC_ASKUMOUNT_CMD, int)
 
 #endif /* _LINUX_AUTO_FS4_H */

[PATCH 6/7] autofs: remove duplicated AUTOFS_DEV_IOCTL_SIZE definition

[Ian Kent]

From: Tomohiro Kusumi <tkusumi@tuxera.com>

This macro is already defined in uapi header.
Also use this macro where possible.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Ian Kent <raven@themaw.net>
---
 fs/autofs4/dev-ioctl.c              |    2 --
 include/uapi/linux/auto_dev-ioctl.h |    4 ++--
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/fs/autofs4/dev-ioctl.c b/fs/autofs4/dev-ioctl.c
index fc09eb7..35099ac 100644
--- a/fs/autofs4/dev-ioctl.c
+++ b/fs/autofs4/dev-ioctl.c
@@ -38,8 +38,6 @@
  * which have been left busy at at service shutdown.
  */
 
-#define AUTOFS_DEV_IOCTL_SIZE	sizeof(struct autofs_dev_ioctl)
-
 typedef int (*ioctl_fn)(struct file *, struct autofs_sb_info *,
 			struct autofs_dev_ioctl *);
 
diff --git a/include/uapi/linux/auto_dev-ioctl.h b/include/uapi/linux/auto_dev-ioctl.h
index af107aa..744b3d0 100644
--- a/include/uapi/linux/auto_dev-ioctl.h
+++ b/include/uapi/linux/auto_dev-ioctl.h
@@ -113,10 +113,10 @@ struct autofs_dev_ioctl {
 
 static inline void init_autofs_dev_ioctl(struct autofs_dev_ioctl *in)
 {
-	memset(in, 0, sizeof(struct autofs_dev_ioctl));
+	memset(in, 0, AUTOFS_DEV_IOCTL_SIZE);
 	in->ver_major = AUTOFS_DEV_IOCTL_VERSION_MAJOR;
 	in->ver_minor = AUTOFS_DEV_IOCTL_VERSION_MINOR;
-	in->size = sizeof(struct autofs_dev_ioctl);
+	in->size = AUTOFS_DEV_IOCTL_SIZE;
 	in->ioctlfd = -1;
 }
 

[PATCH 7/7] autofs - take more care to not update last_used on path walk

[Ian Kent]

GUI environments seem to be becoming more agressive at scanning
filesystems, to the point where autofs cannot expire mounts at
all.

This is one key reason the update of the autofs dentry info
last_used field is done in the expire system when the dentry
is seen to be in use.

But somewhere along the way instances of the update has crept
back into the autofs path walk functions which, with the more
aggressive file access patterns, is preventing expiration.

Changing the update in the path walk functions allows autofs
to at least make progress in spite of frequent immediate
re-mounts from file accesses.

Signed-off-by: Ian Kent <raven@themaw.net>
---
 fs/autofs4/root.c |   17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index a11f731..6ddd4fa 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -281,8 +281,8 @@ static int autofs4_mount_wait(struct dentry *dentry, bool rcu_walk)
 		pr_debug("waiting for mount name=%pd\n", dentry);
 		status = autofs4_wait(sbi, dentry, NFY_MOUNT);
 		pr_debug("mount wait done status=%d\n", status);
+		ino->last_used = jiffies;
 	}
-	ino->last_used = jiffies;
 	return status;
 }
 
@@ -319,16 +319,21 @@ static struct dentry *autofs4_mountpoint_changed(struct path *path)
 	 */
 	if (autofs_type_indirect(sbi->type) && d_unhashed(dentry)) {
 		struct dentry *parent = dentry->d_parent;
-		struct autofs_info *ino;
 		struct dentry *new;
 
 		new = d_lookup(parent, &dentry->d_name);
 		if (!new)
 			return NULL;
-		ino = autofs4_dentry_ino(new);
-		ino->last_used = jiffies;
-		dput(path->dentry);
-		path->dentry = new;
+		if (new == dentry)
+			dput(new);
+		else {
+			struct autofs_info *ino;
+
+			ino = autofs4_dentry_ino(new);
+			ino->last_used = jiffies;
+			dput(path->dentry);
+			path->dentry = new;
+		}
 	}
 	return path->dentry;
 }