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authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /ANDROID_3.4.5/fs/autofs4/expire.c
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'ANDROID_3.4.5/fs/autofs4/expire.c')
-rw-r--r--ANDROID_3.4.5/fs/autofs4/expire.c590
1 files changed, 0 insertions, 590 deletions
diff --git a/ANDROID_3.4.5/fs/autofs4/expire.c b/ANDROID_3.4.5/fs/autofs4/expire.c
deleted file mode 100644
index 1feb68ec..00000000
--- a/ANDROID_3.4.5/fs/autofs4/expire.c
+++ /dev/null
@@ -1,590 +0,0 @@
-/* -*- c -*- --------------------------------------------------------------- *
- *
- * linux/fs/autofs/expire.c
- *
- * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
- * Copyright 1999-2000 Jeremy Fitzhardinge <jeremy@goop.org>
- * Copyright 2001-2006 Ian Kent <raven@themaw.net>
- *
- * This file is part of the Linux kernel and is made available under
- * the terms of the GNU General Public License, version 2, or at your
- * option, any later version, incorporated herein by reference.
- *
- * ------------------------------------------------------------------------- */
-
-#include "autofs_i.h"
-
-static unsigned long now;
-
-/* Check if a dentry can be expired */
-static inline int autofs4_can_expire(struct dentry *dentry,
- unsigned long timeout, int do_now)
-{
- struct autofs_info *ino = autofs4_dentry_ino(dentry);
-
- /* dentry in the process of being deleted */
- if (ino == NULL)
- return 0;
-
- if (!do_now) {
- /* Too young to die */
- if (!timeout || time_after(ino->last_used + timeout, now))
- return 0;
-
- /* update last_used here :-
- - obviously makes sense if it is in use now
- - less obviously, prevents rapid-fire expire
- attempts if expire fails the first time */
- ino->last_used = now;
- }
- return 1;
-}
-
-/* Check a mount point for busyness */
-static int autofs4_mount_busy(struct vfsmount *mnt, struct dentry *dentry)
-{
- struct dentry *top = dentry;
- struct path path = {.mnt = mnt, .dentry = dentry};
- int status = 1;
-
- DPRINTK("dentry %p %.*s",
- dentry, (int)dentry->d_name.len, dentry->d_name.name);
-
- path_get(&path);
-
- if (!follow_down_one(&path))
- goto done;
-
- if (is_autofs4_dentry(path.dentry)) {
- struct autofs_sb_info *sbi = autofs4_sbi(path.dentry->d_sb);
-
- /* This is an autofs submount, we can't expire it */
- if (autofs_type_indirect(sbi->type))
- goto done;
-
- /*
- * Otherwise it's an offset mount and we need to check
- * if we can umount its mount, if there is one.
- */
- if (!d_mountpoint(path.dentry)) {
- status = 0;
- goto done;
- }
- }
-
- /* Update the expiry counter if fs is busy */
- if (!may_umount_tree(path.mnt)) {
- struct autofs_info *ino = autofs4_dentry_ino(top);
- ino->last_used = jiffies;
- goto done;
- }
-
- status = 0;
-done:
- DPRINTK("returning = %d", status);
- path_put(&path);
- return status;
-}
-
-/*
- * Calculate and dget next entry in the subdirs list under root.
- */
-static struct dentry *get_next_positive_subdir(struct dentry *prev,
- struct dentry *root)
-{
- struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb);
- struct list_head *next;
- struct dentry *p, *q;
-
- spin_lock(&sbi->lookup_lock);
-
- if (prev == NULL) {
- spin_lock(&root->d_lock);
- prev = dget_dlock(root);
- next = prev->d_subdirs.next;
- p = prev;
- goto start;
- }
-
- p = prev;
- spin_lock(&p->d_lock);
-again:
- next = p->d_u.d_child.next;
-start:
- if (next == &root->d_subdirs) {
- spin_unlock(&p->d_lock);
- spin_unlock(&sbi->lookup_lock);
- dput(prev);
- return NULL;
- }
-
- q = list_entry(next, struct dentry, d_u.d_child);
-
- spin_lock_nested(&q->d_lock, DENTRY_D_LOCK_NESTED);
- /* Negative dentry - try next */
- if (!simple_positive(q)) {
- spin_unlock(&p->d_lock);
- lock_set_subclass(&q->d_lock.dep_map, 0, _RET_IP_);
- p = q;
- goto again;
- }
- dget_dlock(q);
- spin_unlock(&q->d_lock);
- spin_unlock(&p->d_lock);
- spin_unlock(&sbi->lookup_lock);
-
- dput(prev);
-
- return q;
-}
-
-/*
- * Calculate and dget next entry in top down tree traversal.
- */
-static struct dentry *get_next_positive_dentry(struct dentry *prev,
- struct dentry *root)
-{
- struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb);
- struct list_head *next;
- struct dentry *p, *ret;
-
- if (prev == NULL)
- return dget(root);
-
- spin_lock(&sbi->lookup_lock);
-relock:
- p = prev;
- spin_lock(&p->d_lock);
-again:
- next = p->d_subdirs.next;
- if (next == &p->d_subdirs) {
- while (1) {
- struct dentry *parent;
-
- if (p == root) {
- spin_unlock(&p->d_lock);
- spin_unlock(&sbi->lookup_lock);
- dput(prev);
- return NULL;
- }
-
- parent = p->d_parent;
- if (!spin_trylock(&parent->d_lock)) {
- spin_unlock(&p->d_lock);
- cpu_relax();
- goto relock;
- }
- spin_unlock(&p->d_lock);
- next = p->d_u.d_child.next;
- p = parent;
- if (next != &parent->d_subdirs)
- break;
- }
- }
- ret = list_entry(next, struct dentry, d_u.d_child);
-
- spin_lock_nested(&ret->d_lock, DENTRY_D_LOCK_NESTED);
- /* Negative dentry - try next */
- if (!simple_positive(ret)) {
- spin_unlock(&p->d_lock);
- lock_set_subclass(&ret->d_lock.dep_map, 0, _RET_IP_);
- p = ret;
- goto again;
- }
- dget_dlock(ret);
- spin_unlock(&ret->d_lock);
- spin_unlock(&p->d_lock);
- spin_unlock(&sbi->lookup_lock);
-
- dput(prev);
-
- return ret;
-}
-
-/*
- * Check a direct mount point for busyness.
- * Direct mounts have similar expiry semantics to tree mounts.
- * The tree is not busy iff no mountpoints are busy and there are no
- * autofs submounts.
- */
-static int autofs4_direct_busy(struct vfsmount *mnt,
- struct dentry *top,
- unsigned long timeout,
- int do_now)
-{
- DPRINTK("top %p %.*s",
- top, (int) top->d_name.len, top->d_name.name);
-
- /* If it's busy update the expiry counters */
- if (!may_umount_tree(mnt)) {
- struct autofs_info *ino = autofs4_dentry_ino(top);
- if (ino)
- ino->last_used = jiffies;
- return 1;
- }
-
- /* Timeout of a direct mount is determined by its top dentry */
- if (!autofs4_can_expire(top, timeout, do_now))
- return 1;
-
- return 0;
-}
-
-/* Check a directory tree of mount points for busyness
- * The tree is not busy iff no mountpoints are busy
- */
-static int autofs4_tree_busy(struct vfsmount *mnt,
- struct dentry *top,
- unsigned long timeout,
- int do_now)
-{
- struct autofs_info *top_ino = autofs4_dentry_ino(top);
- struct dentry *p;
-
- DPRINTK("top %p %.*s",
- top, (int)top->d_name.len, top->d_name.name);
-
- /* Negative dentry - give up */
- if (!simple_positive(top))
- return 1;
-
- p = NULL;
- while ((p = get_next_positive_dentry(p, top))) {
- DPRINTK("dentry %p %.*s",
- p, (int) p->d_name.len, p->d_name.name);
-
- /*
- * Is someone visiting anywhere in the subtree ?
- * If there's no mount we need to check the usage
- * count for the autofs dentry.
- * If the fs is busy update the expiry counter.
- */
- if (d_mountpoint(p)) {
- if (autofs4_mount_busy(mnt, p)) {
- top_ino->last_used = jiffies;
- dput(p);
- return 1;
- }
- } else {
- struct autofs_info *ino = autofs4_dentry_ino(p);
- unsigned int ino_count = atomic_read(&ino->count);
-
- /*
- * Clean stale dentries below that have not been
- * invalidated after a mount fail during lookup
- */
- d_invalidate(p);
-
- /* allow for dget above and top is already dgot */
- if (p == top)
- ino_count += 2;
- else
- ino_count++;
-
- if (p->d_count > ino_count) {
- top_ino->last_used = jiffies;
- dput(p);
- return 1;
- }
- }
- }
-
- /* Timeout of a tree mount is ultimately determined by its top dentry */
- if (!autofs4_can_expire(top, timeout, do_now))
- return 1;
-
- return 0;
-}
-
-static struct dentry *autofs4_check_leaves(struct vfsmount *mnt,
- struct dentry *parent,
- unsigned long timeout,
- int do_now)
-{
- struct dentry *p;
-
- DPRINTK("parent %p %.*s",
- parent, (int)parent->d_name.len, parent->d_name.name);
-
- p = NULL;
- while ((p = get_next_positive_dentry(p, parent))) {
- DPRINTK("dentry %p %.*s",
- p, (int) p->d_name.len, p->d_name.name);
-
- if (d_mountpoint(p)) {
- /* Can we umount this guy */
- if (autofs4_mount_busy(mnt, p))
- continue;
-
- /* Can we expire this guy */
- if (autofs4_can_expire(p, timeout, do_now))
- return p;
- }
- }
- return NULL;
-}
-
-/* Check if we can expire a direct mount (possibly a tree) */
-struct dentry *autofs4_expire_direct(struct super_block *sb,
- struct vfsmount *mnt,
- struct autofs_sb_info *sbi,
- int how)
-{
- unsigned long timeout;
- struct dentry *root = dget(sb->s_root);
- int do_now = how & AUTOFS_EXP_IMMEDIATE;
- struct autofs_info *ino;
-
- if (!root)
- return NULL;
-
- now = jiffies;
- timeout = sbi->exp_timeout;
-
- spin_lock(&sbi->fs_lock);
- ino = autofs4_dentry_ino(root);
- /* No point expiring a pending mount */
- if (ino->flags & AUTOFS_INF_PENDING)
- goto out;
- if (!autofs4_direct_busy(mnt, root, timeout, do_now)) {
- struct autofs_info *ino = autofs4_dentry_ino(root);
- ino->flags |= AUTOFS_INF_EXPIRING;
- init_completion(&ino->expire_complete);
- spin_unlock(&sbi->fs_lock);
- return root;
- }
-out:
- spin_unlock(&sbi->fs_lock);
- dput(root);
-
- return NULL;
-}
-
-/*
- * 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_u.d_child);
- spin_unlock(&expired->d_lock);
- spin_unlock(&expired->d_parent->d_lock);
- spin_unlock(&sbi->lookup_lock);
- return expired;
-}
-
-int autofs4_expire_wait(struct dentry *dentry)
-{
- struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
- struct autofs_info *ino = autofs4_dentry_ino(dentry);
- int status;
-
- /* Block on any pending expire */
- spin_lock(&sbi->fs_lock);
- if (ino->flags & AUTOFS_INF_EXPIRING) {
- spin_unlock(&sbi->fs_lock);
-
- DPRINTK("waiting for expire %p name=%.*s",
- dentry, dentry->d_name.len, dentry->d_name.name);
-
- status = autofs4_wait(sbi, dentry, NFY_NONE);
- wait_for_completion(&ino->expire_complete);
-
- DPRINTK("expire done status=%d", status);
-
- if (d_unhashed(dentry))
- return -EAGAIN;
-
- return status;
- }
- spin_unlock(&sbi->fs_lock);
-
- return 0;
-}
-
-/* Perform an expiry operation */
-int autofs4_expire_run(struct super_block *sb,
- struct vfsmount *mnt,
- struct autofs_sb_info *sbi,
- struct autofs_packet_expire __user *pkt_p)
-{
- struct autofs_packet_expire pkt;
- struct autofs_info *ino;
- struct dentry *dentry;
- int ret = 0;
-
- memset(&pkt,0,sizeof pkt);
-
- pkt.hdr.proto_version = sbi->version;
- pkt.hdr.type = autofs_ptype_expire;
-
- if ((dentry = autofs4_expire_indirect(sb, mnt, sbi, 0)) == NULL)
- return -EAGAIN;
-
- pkt.len = dentry->d_name.len;
- memcpy(pkt.name, dentry->d_name.name, pkt.len);
- pkt.name[pkt.len] = '\0';
- dput(dentry);
-
- if ( copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire)) )
- ret = -EFAULT;
-
- spin_lock(&sbi->fs_lock);
- ino = autofs4_dentry_ino(dentry);
- ino->flags &= ~AUTOFS_INF_EXPIRING;
- complete_all(&ino->expire_complete);
- spin_unlock(&sbi->fs_lock);
-
- return ret;
-}
-
-int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt,
- struct autofs_sb_info *sbi, int when)
-{
- struct dentry *dentry;
- int ret = -EAGAIN;
-
- if (autofs_type_trigger(sbi->type))
- dentry = autofs4_expire_direct(sb, mnt, sbi, when);
- else
- dentry = autofs4_expire_indirect(sb, mnt, sbi, when);
-
- if (dentry) {
- struct autofs_info *ino = autofs4_dentry_ino(dentry);
-
- /* This is synchronous because it makes the daemon a
- little easier */
- ret = autofs4_wait(sbi, dentry, NFY_EXPIRE);
-
- spin_lock(&sbi->fs_lock);
- ino->flags &= ~AUTOFS_INF_EXPIRING;
- spin_lock(&dentry->d_lock);
- if (!ret) {
- if ((IS_ROOT(dentry) ||
- (autofs_type_indirect(sbi->type) &&
- IS_ROOT(dentry->d_parent))) &&
- !(dentry->d_flags & DCACHE_NEED_AUTOMOUNT))
- __managed_dentry_set_automount(dentry);
- }
- spin_unlock(&dentry->d_lock);
- complete_all(&ino->expire_complete);
- spin_unlock(&sbi->fs_lock);
- dput(dentry);
- }
-
- return ret;
-}
-
-/* Call repeatedly until it returns -EAGAIN, meaning there's nothing
- more to be done */
-int autofs4_expire_multi(struct super_block *sb, struct vfsmount *mnt,
- struct autofs_sb_info *sbi, int __user *arg)
-{
- int do_now = 0;
-
- if (arg && get_user(do_now, arg))
- return -EFAULT;
-
- return autofs4_do_expire_multi(sb, mnt, sbi, do_now);
-}
-