struct dentry *autofs4_expire_indirect(struct super_block *sb, struct vfsmount *mnt, struct autofs_sb_info *sbi, int how) { unsigned long timeout; struct dentry *root = sb->s_root; struct dentry *dentry; struct dentry *expired = NULL; int do_now = how & AUTOFS_EXP_IMMEDIATE; int exp_leaves = how & AUTOFS_EXP_LEAVES; struct autofs_info *ino; unsigned int ino_count; if (!root) return NULL; now = jiffies; timeout = sbi->exp_timeout; dentry = NULL; while ((dentry = get_next_positive_subdir(dentry, root))) { spin_lock(&sbi->fs_lock); ino = autofs4_dentry_ino(dentry); if (ino->flags & AUTOFS_INF_PENDING) goto next; if (d_mountpoint(dentry)) { DPRINTK("checking mountpoint %p %.*s", dentry, (int)dentry->d_name.len, dentry->d_name.name); ino_count = atomic_read(&ino->count) + 2; if (dentry->d_count > ino_count) goto next; if (autofs4_mount_busy(mnt, dentry)) goto next; if (autofs4_can_expire(dentry, timeout, do_now)) { expired = dentry; goto found; } goto next; } if (simple_empty(dentry)) goto next; if (!exp_leaves) { ino_count = atomic_read(&ino->count) + 1; if (dentry->d_count > ino_count) goto next; if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) { expired = dentry; goto found; } } else { ino_count = atomic_read(&ino->count) + 1; if (dentry->d_count > ino_count) goto next; expired = autofs4_check_leaves(mnt, dentry, timeout, do_now); if (expired) { dput(dentry); goto found; } } next: spin_unlock(&sbi->fs_lock); } return NULL; found: DPRINTK("returning %p %.*s", expired, (int)expired->d_name.len, expired->d_name.name); ino = autofs4_dentry_ino(expired); ino->flags |= AUTOFS_INF_EXPIRING; init_completion(&ino->expire_complete); spin_unlock(&sbi->fs_lock); spin_lock(&sbi->lookup_lock); spin_lock(&expired->d_parent->d_lock); spin_lock_nested(&expired->d_lock, DENTRY_D_LOCK_NESTED); list_move(&expired->d_parent->d_subdirs, &expired->d_u.d_child); spin_unlock(&expired->d_lock); spin_unlock(&expired->d_parent->d_lock); spin_unlock(&sbi->lookup_lock); return expired; }
/* * Find an eligible tree to time-out * A tree is eligible if :- * - it is unused by any user process * - it has been unused for exp_timeout time */ struct dentry *autofs4_expire_indirect(struct super_block *sb, struct vfsmount *mnt, struct autofs_sb_info *sbi, int how) { unsigned long timeout; struct dentry *root = sb->s_root; struct dentry *dentry; struct dentry *expired; struct dentry *found; struct autofs_info *ino; if (!root) return NULL; now = jiffies; timeout = sbi->exp_timeout; dentry = NULL; while ((dentry = get_next_positive_subdir(dentry, root))) { int flags = how; spin_lock(&sbi->fs_lock); ino = autofs4_dentry_ino(dentry); if (ino->flags & AUTOFS_INF_WANT_EXPIRE) { spin_unlock(&sbi->fs_lock); continue; } spin_unlock(&sbi->fs_lock); expired = should_expire(dentry, mnt, timeout, flags); if (!expired) continue; spin_lock(&sbi->fs_lock); ino = autofs4_dentry_ino(expired); ino->flags |= AUTOFS_INF_WANT_EXPIRE; spin_unlock(&sbi->fs_lock); synchronize_rcu(); /* Make sure a reference is not taken on found if * things have changed. */ flags &= ~AUTOFS_EXP_LEAVES; found = should_expire(expired, mnt, timeout, how); if (!found || found != expired) /* Something has changed, continue */ goto next; if (expired != dentry) dput(dentry); spin_lock(&sbi->fs_lock); goto found; next: spin_lock(&sbi->fs_lock); ino->flags &= ~AUTOFS_INF_WANT_EXPIRE; spin_unlock(&sbi->fs_lock); if (expired != dentry) dput(expired); } return NULL; found: pr_debug("returning %p %pd\n", expired, expired); ino->flags |= AUTOFS_INF_EXPIRING; init_completion(&ino->expire_complete); spin_unlock(&sbi->fs_lock); return expired; }
/* * Find an eligible tree to time-out * A tree is eligible if :- * - it is unused by any user process * - it has been unused for exp_timeout time */ struct dentry *autofs4_expire_indirect(struct super_block *sb, struct vfsmount *mnt, struct autofs_sb_info *sbi, int how) { unsigned long timeout; struct dentry *root = sb->s_root; struct dentry *dentry; struct dentry *expired = NULL; int do_now = how & AUTOFS_EXP_IMMEDIATE; int exp_leaves = how & AUTOFS_EXP_LEAVES; struct autofs_info *ino; unsigned int ino_count; if (!root) return NULL; now = jiffies; timeout = sbi->exp_timeout; dentry = NULL; while ((dentry = get_next_positive_subdir(dentry, root))) { spin_lock(&sbi->fs_lock); ino = autofs4_dentry_ino(dentry); /* No point expiring a pending mount */ if (ino->flags & AUTOFS_INF_PENDING) goto next; /* * Case 1: (i) indirect mount or top level pseudo direct mount * (autofs-4.1). * (ii) indirect mount with offset mount, check the "/" * offset (autofs-5.0+). */ if (d_mountpoint(dentry)) { DPRINTK("checking mountpoint %p %.*s", dentry, (int)dentry->d_name.len, dentry->d_name.name); /* Path walk currently on this dentry? */ ino_count = atomic_read(&ino->count) + 2; if (dentry->d_count > ino_count) goto next; /* Can we umount this guy */ if (autofs4_mount_busy(mnt, dentry)) goto next; /* Can we expire this guy */ if (autofs4_can_expire(dentry, timeout, do_now)) { expired = dentry; goto found; } goto next; } if (simple_empty(dentry)) goto next; /* Case 2: tree mount, expire iff entire tree is not busy */ if (!exp_leaves) { /* Path walk currently on this dentry? */ ino_count = atomic_read(&ino->count) + 1; if (dentry->d_count > ino_count) goto next; if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) { expired = dentry; goto found; } /* * Case 3: pseudo direct mount, expire individual leaves * (autofs-4.1). */ } else { /* Path walk currently on this dentry? */ ino_count = atomic_read(&ino->count) + 1; if (dentry->d_count > ino_count) goto next; expired = autofs4_check_leaves(mnt, dentry, timeout, do_now); if (expired) { dput(dentry); goto found; } } next: spin_unlock(&sbi->fs_lock); } return NULL; found: DPRINTK("returning %p %.*s", expired, (int)expired->d_name.len, expired->d_name.name); ino = autofs4_dentry_ino(expired); ino->flags |= AUTOFS_INF_EXPIRING; init_completion(&ino->expire_complete); spin_unlock(&sbi->fs_lock); spin_lock(&sbi->lookup_lock); spin_lock(&expired->d_parent->d_lock); spin_lock_nested(&expired->d_lock, DENTRY_D_LOCK_NESTED); list_move(&expired->d_parent->d_subdirs, &expired->d_child); spin_unlock(&expired->d_lock); spin_unlock(&expired->d_parent->d_lock); spin_unlock(&sbi->lookup_lock); return expired; }