diff options
| -rw-r--r-- | fs/autofs/expire.c | 62 | ||||
| -rw-r--r-- | include/uapi/linux/auto_fs.h | 8 |
2 files changed, 55 insertions, 15 deletions
diff --git a/fs/autofs/expire.c b/fs/autofs/expire.c index dfb666c5b8a2..d441244b79df 100644 --- a/fs/autofs/expire.c +++ b/fs/autofs/expire.c @@ -29,7 +29,8 @@ static inline int autofs_can_expire(struct dentry *dentry, } /* Check a mount point for busyness */ -static int autofs_mount_busy(struct vfsmount *mnt, struct dentry *dentry) +static int autofs_mount_busy(struct vfsmount *mnt, + struct dentry *dentry, unsigned int how) { struct dentry *top = dentry; struct path path = {.mnt = mnt, .dentry = dentry}; @@ -50,6 +51,12 @@ static int autofs_mount_busy(struct vfsmount *mnt, struct dentry *dentry) goto done; } + /* Not a submount, has a forced expire been requested */ + if (how & AUTOFS_EXP_FORCED) { + status = 0; + goto done; + } + /* Update the expiry counter if fs is busy */ if (!may_umount_tree(path.mnt)) { struct autofs_info *ino; @@ -189,6 +196,10 @@ static int autofs_direct_busy(struct vfsmount *mnt, { pr_debug("top %p %pd\n", top, top); + /* Forced expire, user space handles busy mounts */ + if (how & AUTOFS_EXP_FORCED) + return 0; + /* If it's busy update the expiry counters */ if (!may_umount_tree(mnt)) { struct autofs_info *ino; @@ -235,7 +246,7 @@ static int autofs_tree_busy(struct vfsmount *mnt, * If the fs is busy update the expiry counter. */ if (d_mountpoint(p)) { - if (autofs_mount_busy(mnt, p)) { + if (autofs_mount_busy(mnt, p, how)) { top_ino->last_used = jiffies; dput(p); return 1; @@ -258,6 +269,10 @@ static int autofs_tree_busy(struct vfsmount *mnt, } } + /* Forced expire, user space handles busy mounts */ + if (how & AUTOFS_EXP_FORCED) + return 0; + /* Timeout of a tree mount is ultimately determined by its top dentry */ if (!autofs_can_expire(top, timeout, how)) return 1; @@ -280,9 +295,15 @@ static struct dentry *autofs_check_leaves(struct vfsmount *mnt, if (d_mountpoint(p)) { /* Can we umount this guy */ - if (autofs_mount_busy(mnt, p)) + if (autofs_mount_busy(mnt, p, how)) continue; + /* This isn't a submount so if a forced expire + * has been requested, user space handles busy + * mounts */ + if (how & AUTOFS_EXP_FORCED) + return p; + /* Can we expire this guy */ if (autofs_can_expire(p, timeout, how)) return p; @@ -361,9 +382,15 @@ static struct dentry *should_expire(struct dentry *dentry, pr_debug("checking mountpoint %p %pd\n", dentry, dentry); /* Can we umount this guy */ - if (autofs_mount_busy(mnt, dentry)) + if (autofs_mount_busy(mnt, dentry, how)) return NULL; + /* This isn't a submount so if a forced expire + * has been requested, user space handles busy + * mounts */ + if (how & AUTOFS_EXP_FORCED) + return dentry; + /* Can we expire this guy */ if (autofs_can_expire(dentry, timeout, how)) return dentry; @@ -372,6 +399,11 @@ static struct dentry *should_expire(struct dentry *dentry, if (d_really_is_positive(dentry) && d_is_symlink(dentry)) { pr_debug("checking symlink %p %pd\n", dentry, dentry); + + /* Forced expire, user space handles busy mounts */ + if (how & AUTOFS_EXP_FORCED) + return dentry; + /* * A symlink can't be "busy" in the usual sense so * just check last used for expire timeout. @@ -386,10 +418,13 @@ static struct dentry *should_expire(struct dentry *dentry, /* Case 2: tree mount, expire iff entire tree is not busy */ if (!(how & AUTOFS_EXP_LEAVES)) { - /* Path walk currently on this dentry? */ - ino_count = atomic_read(&ino->count) + 1; - if (d_count(dentry) > ino_count) - return NULL; + /* Not a forced expire? */ + if (!(how & AUTOFS_EXP_FORCED)) { + /* ref-walk currently on this dentry? */ + ino_count = atomic_read(&ino->count) + 1; + if (d_count(dentry) > ino_count) + return NULL; + } if (!autofs_tree_busy(mnt, dentry, timeout, how)) return dentry; @@ -398,12 +433,15 @@ static struct dentry *should_expire(struct dentry *dentry, * (autofs-4.1). */ } else { - /* Path walk currently on this dentry? */ struct dentry *expired; - ino_count = atomic_read(&ino->count) + 1; - if (d_count(dentry) > ino_count) - return NULL; + /* Not a forced expire? */ + if (!(how & AUTOFS_EXP_FORCED)) { + /* ref-walk currently on this dentry? */ + ino_count = atomic_read(&ino->count) + 1; + if (d_count(dentry) > ino_count) + return NULL; + } expired = autofs_check_leaves(mnt, dentry, timeout, how); if (expired) { diff --git a/include/uapi/linux/auto_fs.h b/include/uapi/linux/auto_fs.h index e13eec3dfb2f..df31aa9c9a8c 100644 --- a/include/uapi/linux/auto_fs.h +++ b/include/uapi/linux/auto_fs.h @@ -23,7 +23,7 @@ #define AUTOFS_MIN_PROTO_VERSION 3 #define AUTOFS_MAX_PROTO_VERSION 5 -#define AUTOFS_PROTO_SUBVERSION 2 +#define AUTOFS_PROTO_SUBVERSION 3 /* * The wait_queue_token (autofs_wqt_t) is part of a structure which is passed @@ -90,8 +90,10 @@ enum { /* autofs version 4 and later definitions */ /* Mask for expire behaviour */ -#define AUTOFS_EXP_IMMEDIATE 1 -#define AUTOFS_EXP_LEAVES 2 +#define AUTOFS_EXP_NORMAL 0x00 +#define AUTOFS_EXP_IMMEDIATE 0x01 +#define AUTOFS_EXP_LEAVES 0x02 +#define AUTOFS_EXP_FORCED 0x04 #define AUTOFS_TYPE_ANY 0U #define AUTOFS_TYPE_INDIRECT 1U |