aboutsummaryrefslogtreecommitdiffstats
path: root/fs/autofs4/root.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/autofs4/root.c')
-rw-r--r--fs/autofs4/root.c23
1 files changed, 22 insertions, 1 deletions
diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index c7ff35774344..d196712c4b94 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -490,6 +490,7 @@ static int autofs4_dir_symlink(struct inode *dir,
490{ 490{
491 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb); 491 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
492 struct autofs_info *ino = autofs4_dentry_ino(dentry); 492 struct autofs_info *ino = autofs4_dentry_ino(dentry);
493 struct autofs_info *p_ino;
493 struct inode *inode; 494 struct inode *inode;
494 char *cp; 495 char *cp;
495 496
@@ -523,6 +524,10 @@ static int autofs4_dir_symlink(struct inode *dir,
523 524
524 dentry->d_fsdata = ino; 525 dentry->d_fsdata = ino;
525 ino->dentry = dget(dentry); 526 ino->dentry = dget(dentry);
527 atomic_inc(&ino->count);
528 p_ino = autofs4_dentry_ino(dentry->d_parent);
529 if (p_ino && dentry->d_parent != dentry)
530 atomic_inc(&p_ino->count);
526 ino->inode = inode; 531 ino->inode = inode;
527 532
528 dir->i_mtime = CURRENT_TIME; 533 dir->i_mtime = CURRENT_TIME;
@@ -549,11 +554,17 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)
549{ 554{
550 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb); 555 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
551 struct autofs_info *ino = autofs4_dentry_ino(dentry); 556 struct autofs_info *ino = autofs4_dentry_ino(dentry);
557 struct autofs_info *p_ino;
552 558
553 /* This allows root to remove symlinks */ 559 /* This allows root to remove symlinks */
554 if ( !autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) ) 560 if ( !autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) )
555 return -EACCES; 561 return -EACCES;
556 562
563 if (atomic_dec_and_test(&ino->count)) {
564 p_ino = autofs4_dentry_ino(dentry->d_parent);
565 if (p_ino && dentry->d_parent != dentry)
566 atomic_dec(&p_ino->count);
567 }
557 dput(ino->dentry); 568 dput(ino->dentry);
558 569
559 dentry->d_inode->i_size = 0; 570 dentry->d_inode->i_size = 0;
@@ -570,6 +581,7 @@ static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)
570{ 581{
571 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb); 582 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
572 struct autofs_info *ino = autofs4_dentry_ino(dentry); 583 struct autofs_info *ino = autofs4_dentry_ino(dentry);
584 struct autofs_info *p_ino;
573 585
574 if (!autofs4_oz_mode(sbi)) 586 if (!autofs4_oz_mode(sbi))
575 return -EACCES; 587 return -EACCES;
@@ -584,8 +596,12 @@ static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)
584 spin_unlock(&dentry->d_lock); 596 spin_unlock(&dentry->d_lock);
585 spin_unlock(&dcache_lock); 597 spin_unlock(&dcache_lock);
586 598
599 if (atomic_dec_and_test(&ino->count)) {
600 p_ino = autofs4_dentry_ino(dentry->d_parent);
601 if (p_ino && dentry->d_parent != dentry)
602 atomic_dec(&p_ino->count);
603 }
587 dput(ino->dentry); 604 dput(ino->dentry);
588
589 dentry->d_inode->i_size = 0; 605 dentry->d_inode->i_size = 0;
590 dentry->d_inode->i_nlink = 0; 606 dentry->d_inode->i_nlink = 0;
591 607
@@ -599,6 +615,7 @@ static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, int mode)
599{ 615{
600 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb); 616 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
601 struct autofs_info *ino = autofs4_dentry_ino(dentry); 617 struct autofs_info *ino = autofs4_dentry_ino(dentry);
618 struct autofs_info *p_ino;
602 struct inode *inode; 619 struct inode *inode;
603 620
604 if ( !autofs4_oz_mode(sbi) ) 621 if ( !autofs4_oz_mode(sbi) )
@@ -621,6 +638,10 @@ static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, int mode)
621 638
622 dentry->d_fsdata = ino; 639 dentry->d_fsdata = ino;
623 ino->dentry = dget(dentry); 640 ino->dentry = dget(dentry);
641 atomic_inc(&ino->count);
642 p_ino = autofs4_dentry_ino(dentry->d_parent);
643 if (p_ino && dentry->d_parent != dentry)
644 atomic_inc(&p_ino->count);
624 ino->inode = inode; 645 ino->inode = inode;
625 dir->i_nlink++; 646 dir->i_nlink++;
626 dir->i_mtime = CURRENT_TIME; 647 dir->i_mtime = CURRENT_TIME;
generated by cgit v1.2.2 (git 2.25.0) at 2025-03-07 11:10:09 -0500
class="hl kwb">struct dentry *dentry = NULL; const char *name = "?"; if (!list_empty(&inode->i_dentry)) { dentry = list_entry(inode->i_dentry.next, struct dentry, d_alias); if (dentry && dentry->d_name.name) name = (const char *) dentry->d_name.name; } if (inode->i_ino || strcmp(inode->i_sb->s_id, "bdev")) printk(KERN_DEBUG "%s(%d): dirtied inode %lu (%s) on %s\n", current->comm, task_pid_nr(current), inode->i_ino, name, inode->i_sb->s_id); } spin_lock(&inode_lock); if ((inode->i_state & flags) != flags) { const int was_dirty = inode->i_state & I_DIRTY; inode->i_state |= flags; /* * If the inode is being synced, just update its dirty state. * The unlocker will place the inode on the appropriate * superblock list, based upon its state. */ if (inode->i_state & I_SYNC) goto out; /* * Only add valid (hashed) inodes to the superblock's * dirty list. Add blockdev inodes as well. */ if (!S_ISBLK(inode->i_mode)) { if (hlist_unhashed(&inode->i_hash)) goto out; } if (inode->i_state & (I_FREEING|I_CLEAR)) goto out; /* * If the inode was already on s_dirty/s_io/s_more_io, don't * reposition it (that would break s_dirty time-ordering). */ if (!was_dirty) { inode->dirtied_when = jiffies; list_move(&inode->i_list, &sb->s_dirty); } } out: spin_unlock(&inode_lock); } EXPORT_SYMBOL(__mark_inode_dirty); static int write_inode(struct inode *inode, int sync) { if (inode->i_sb->s_op->write_inode && !is_bad_inode(inode)) return inode->i_sb->s_op->write_inode(inode, sync); return 0; } /* * Redirty an inode: set its when-it-was dirtied timestamp and move it to the * furthest end of its superblock's dirty-inode list. * * Before stamping the inode's ->dirtied_when, we check to see whether it is * already the most-recently-dirtied inode on the s_dirty list. If that is * the case then the inode must have been redirtied while it was being written * out and we don't reset its dirtied_when. */ static void redirty_tail(struct inode *inode) { struct super_block *sb = inode->i_sb; if (!list_empty(&sb->s_dirty)) { struct inode *tail_inode; tail_inode = list_entry(sb->s_dirty.next, struct inode, i_list); if (!time_after_eq(inode->dirtied_when, tail_inode->dirtied_when)) inode->dirtied_when = jiffies; } list_move(&inode->i_list, &sb->s_dirty); } /* * requeue inode for re-scanning after sb->s_io list is exhausted. */ static void requeue_io(struct inode *inode) { list_move(&inode->i_list, &inode->i_sb->s_more_io); } static void inode_sync_complete(struct inode *inode) { /* * Prevent speculative execution through spin_unlock(&inode_lock); */ smp_mb(); wake_up_bit(&inode->i_state, __I_SYNC); } /* * Move expired dirty inodes from @delaying_queue to @dispatch_queue. */ static void move_expired_inodes(struct list_head *delaying_queue, struct list_head *dispatch_queue, unsigned long *older_than_this) { while (!list_empty(delaying_queue)) { struct inode *inode = list_entry(delaying_queue->prev, struct inode, i_list); if (older_than_this && time_after(inode->dirtied_when, *older_than_this)) break; list_move(&inode->i_list, dispatch_queue); } } /* * Queue all expired dirty inodes for io, eldest first. */ static void queue_io(struct super_block *sb, unsigned long *older_than_this) { list_splice_init(&sb->s_more_io, sb->s_io.prev); move_expired_inodes(&sb->s_dirty, &sb->s_io, older_than_this); } int sb_has_dirty_inodes(struct super_block *sb) { return !list_empty(&sb->s_dirty) || !list_empty(&sb->s_io) || !list_empty(&sb->s_more_io); } EXPORT_SYMBOL(sb_has_dirty_inodes); /* * Write a single inode's dirty pages and inode data out to disk. * If `wait' is set, wait on the writeout. * * The whole writeout design is quite complex and fragile. We want to avoid * starvation of particular inodes when others are being redirtied, prevent * livelocks, etc. * * Called under inode_lock. */ static int __sync_single_inode(struct inode *inode, struct writeback_control *wbc) { unsigned dirty; struct address_space *mapping = inode->i_mapping; int wait = wbc->sync_mode == WB_SYNC_ALL; int ret; BUG_ON(inode->i_state & I_SYNC); /* Set I_SYNC, reset I_DIRTY */ dirty = inode->i_state & I_DIRTY; inode->i_state |= I_SYNC; inode->i_state &= ~I_DIRTY; spin_unlock(&inode_lock); ret = do_writepages(mapping, wbc); /* Don't write the inode if only I_DIRTY_PAGES was set */ if (dirty & (I_DIRTY_SYNC | I_DIRTY_DATASYNC)) { int err = write_inode(inode, wait); if (ret == 0) ret = err; } if (wait) { int err = filemap_fdatawait(mapping); if (ret == 0) ret = err; } spin_lock(&inode_lock); inode->i_state &= ~I_SYNC; if (!(inode->i_state & I_FREEING)) { if (!(inode->i_state & I_DIRTY) && mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) { /* * We didn't write back all the pages. nfs_writepages() * sometimes bales out without doing anything. Redirty * the inode; Move it from s_io onto s_more_io/s_dirty. */ /* * akpm: if the caller was the kupdate function we put * this inode at the head of s_dirty so it gets first * consideration. Otherwise, move it to the tail, for * the reasons described there. I'm not really sure * how much sense this makes. Presumably I had a good * reasons for doing it this way, and I'd rather not * muck with it at present. */ if (wbc->for_kupdate) { /* * For the kupdate function we move the inode * to s_more_io so it will get more writeout as * soon as the queue becomes uncongested. */ inode->i_state |= I_DIRTY_PAGES; if (wbc->nr_to_write <= 0) { /* * slice used up: queue for next turn */ requeue_io(inode); } else { /* * somehow blocked: retry later */ redirty_tail(inode); } } else { /* * Otherwise fully redirty the inode so that * other inodes on this superblock will get some * writeout. Otherwise heavy writing to one * file would indefinitely suspend writeout of * all the other files. */ inode->i_state |= I_DIRTY_PAGES; redirty_tail(inode); } } else if (inode->i_state & I_DIRTY) { /* * Someone redirtied the inode while were writing back * the pages. */ redirty_tail(inode); } else if (atomic_read(&inode->i_count)) { /* * The inode is clean, inuse */ list_move(&inode->i_list, &inode_in_use); } else { /* * The inode is clean, unused */ list_move(&inode->i_list, &inode_unused); } } inode_sync_complete(inode); return ret; } /* * Write out an inode's dirty pages. Called under inode_lock. Either the * caller has ref on the inode (either via __iget or via syscall against an fd) * or the inode has I_WILL_FREE set (via generic_forget_inode) */ static int __writeback_single_inode(struct inode *inode, struct writeback_control *wbc) { wait_queue_head_t *wqh; if (!atomic_read(&inode->i_count)) WARN_ON(!(inode->i_state & (I_WILL_FREE|I_FREEING))); else WARN_ON(inode->i_state & I_WILL_FREE); if ((wbc->sync_mode != WB_SYNC_ALL) && (inode->i_state & I_SYNC)) { /* * We're skipping this inode because it's locked, and we're not * doing writeback-for-data-integrity. Move it to s_more_io so * that writeback can proceed with the other inodes on s_io. * We'll have another go at writing back this inode when we * completed a full scan of s_io. */ requeue_io(inode); return 0; } /* * It's a data-integrity sync. We must wait. */ if (inode->i_state & I_SYNC) { DEFINE_WAIT_BIT(wq, &inode->i_state, __I_SYNC); wqh = bit_waitqueue(&inode->i_state, __I_SYNC); do { spin_unlock(&inode_lock); __wait_on_bit(wqh, &wq, inode_wait, TASK_UNINTERRUPTIBLE); spin_lock(&inode_lock); } while (inode->i_state & I_SYNC); } return __sync_single_inode(inode, wbc); } /* * Write out a superblock's list of dirty inodes. A wait will be performed * upon no inodes, all inodes or the final one, depending upon sync_mode. * * If older_than_this is non-NULL, then only write out inodes which * had their first dirtying at a time earlier than *older_than_this. * * If we're a pdlfush thread, then implement pdflush collision avoidance * against the entire list. * * WB_SYNC_HOLD is a hack for sys_sync(): reattach the inode to sb->s_dirty so * that it can be located for waiting on in __writeback_single_inode(). * * If `bdi' is non-zero then we're being asked to writeback a specific queue. * This function assumes that the blockdev superblock's inodes are backed by * a variety of queues, so all inodes are searched. For other superblocks, * assume that all inodes are backed by the same queue. * * FIXME: this linear search could get expensive with many fileystems. But * how to fix? We need to go from an address_space to all inodes which share * a queue with that address_space. (Easy: have a global "dirty superblocks" * list). * * The inodes to be written are parked on sb->s_io. They are moved back onto * sb->s_dirty as they are selected for writing. This way, none can be missed * on the writer throttling path, and we get decent balancing between many * throttled threads: we don't want them all piling up on inode_sync_wait. */ void generic_sync_sb_inodes(struct super_block *sb, struct writeback_control *wbc) { const unsigned long start = jiffies; /* livelock avoidance */ spin_lock(&inode_lock); if (!wbc->for_kupdate || list_empty(&sb->s_io)) queue_io(sb, wbc->older_than_this); while (!list_empty(&sb->s_io)) { struct inode *inode = list_entry(sb->s_io.prev, struct inode, i_list); struct address_space *mapping = inode->i_mapping; struct backing_dev_info *bdi = mapping->backing_dev_info; long pages_skipped; if (!bdi_cap_writeback_dirty(bdi)) { redirty_tail(inode); if (sb_is_blkdev_sb(sb)) { /* * Dirty memory-backed blockdev: the ramdisk * driver does this. Skip just this inode */ continue; } /* * Dirty memory-backed inode against a filesystem other * than the kernel-internal bdev filesystem. Skip the * entire superblock. */ break; } if (wbc->nonblocking && bdi_write_congested(bdi)) { wbc->encountered_congestion = 1; if (!sb_is_blkdev_sb(sb)) break; /* Skip a congested fs */ requeue_io(inode); continue; /* Skip a congested blockdev */ } if (wbc->bdi && bdi != wbc->bdi) { if (!sb_is_blkdev_sb(sb)) break; /* fs has the wrong queue */ requeue_io(inode); continue; /* blockdev has wrong queue */ } /* Was this inode dirtied after sync_sb_inodes was called? */ if (time_after(inode->dirtied_when, start)) break; /* Is another pdflush already flushing this queue? */ if (current_is_pdflush() && !writeback_acquire(bdi)) break; BUG_ON(inode->i_state & I_FREEING); __iget(inode); pages_skipped = wbc->pages_skipped; __writeback_single_inode(inode, wbc); if (wbc->sync_mode == WB_SYNC_HOLD) { inode->dirtied_when = jiffies; list_move(&inode->i_list, &sb->s_dirty); } if (current_is_pdflush()) writeback_release(bdi); if (wbc->pages_skipped != pages_skipped) { /* * writeback is not making progress due to locked * buffers. Skip this inode for now. */ redirty_tail(inode); } spin_unlock(&inode_lock); iput(inode); cond_resched(); spin_lock(&inode_lock); if (wbc->nr_to_write <= 0) { wbc->more_io = 1; break; } if (!list_empty(&sb->s_more_io)) wbc->more_io = 1; } spin_unlock(&inode_lock); return; /* Leave any unwritten inodes on s_io */ } EXPORT_SYMBOL_GPL(generic_sync_sb_inodes); static void sync_sb_inodes(struct super_block *sb, struct writeback_control *wbc) { generic_sync_sb_inodes(sb, wbc); } /* * Start writeback of dirty pagecache data against all unlocked inodes. * * Note: * We don't need to grab a reference to superblock here. If it has non-empty * ->s_dirty it's hadn't been killed yet and kill_super() won't proceed * past sync_inodes_sb() until the ->s_dirty/s_io/s_more_io lists are all * empty. Since __sync_single_inode() regains inode_lock before it finally moves * inode from superblock lists we are OK. * * If `older_than_this' is non-zero then only flush inodes which have a * flushtime older than *older_than_this. * * If `bdi' is non-zero then we will scan the first inode against each * superblock until we find the matching ones. One group will be the dirty * inodes against a filesystem. Then when we hit the dummy blockdev superblock, * sync_sb_inodes will seekout the blockdev which matches `bdi'. Maybe not * super-efficient but we're about to do a ton of I/O... */ void writeback_inodes(struct writeback_control *wbc) { struct super_block *sb; might_sleep(); spin_lock(&sb_lock); restart: list_for_each_entry_reverse(sb, &super_blocks, s_list) { if (sb_has_dirty_inodes(sb)) { /* we're making our own get_super here */ sb->s_count++; spin_unlock(&sb_lock); /* * If we can't get the readlock, there's no sense in * waiting around, most of the time the FS is going to * be unmounted by the time it is released. */ if (down_read_trylock(&sb->s_umount)) { if (sb->s_root) sync_sb_inodes(sb, wbc); up_read(&sb->s_umount); } spin_lock(&sb_lock); if (__put_super_and_need_restart(sb)) goto restart; } if (wbc->nr_to_write <= 0) break; } spin_unlock(&sb_lock); } /* * writeback and wait upon the filesystem's dirty inodes. The caller will * do this in two passes - one to write, and one to wait. WB_SYNC_HOLD is * used to park the written inodes on sb->s_dirty for the wait pass. * * A finite limit is set on the number of pages which will be written. * To prevent infinite livelock of sys_sync(). * * We add in the number of potentially dirty inodes, because each inode write * can dirty pagecache in the underlying blockdev. */ void sync_inodes_sb(struct super_block *sb, int wait) { struct writeback_control wbc = { .sync_mode = wait ? WB_SYNC_ALL : WB_SYNC_HOLD, .range_start = 0, .range_end = LLONG_MAX, }; unsigned long nr_dirty = global_page_state(NR_FILE_DIRTY); unsigned long nr_unstable = global_page_state(NR_UNSTABLE_NFS); wbc.nr_to_write = nr_dirty + nr_unstable + (inodes_stat.nr_inodes - inodes_stat.nr_unused) + nr_dirty + nr_unstable; wbc.nr_to_write += wbc.nr_to_write / 2; /* Bit more for luck */ sync_sb_inodes(sb, &wbc); } /* * Rather lame livelock avoidance. */ static void set_sb_syncing(int val) { struct super_block *sb; spin_lock(&sb_lock); list_for_each_entry_reverse(sb, &super_blocks, s_list) sb->s_syncing = val; spin_unlock(&sb_lock); } /** * sync_inodes - writes all inodes to disk * @wait: wait for completion * * sync_inodes() goes through each super block's dirty inode list, writes the * inodes out, waits on the writeout and puts the inodes back on the normal * list. * * This is for sys_sync(). fsync_dev() uses the same algorithm. The subtle * part of the sync functions is that the blockdev "superblock" is processed * last. This is because the write_inode() function of a typical fs will * perform no I/O, but will mark buffers in the blockdev mapping as dirty. * What we want to do is to perform all that dirtying first, and then write * back all those inode blocks via the blockdev mapping in one sweep. So the * additional (somewhat redundant) sync_blockdev() calls here are to make * sure that really happens. Because if we call sync_inodes_sb(wait=1) with * outstanding dirty inodes, the writeback goes block-at-a-time within the * filesystem's write_inode(). This is extremely slow. */ static void __sync_inodes(int wait) { struct super_block *sb; spin_lock(&sb_lock); restart: list_for_each_entry(sb, &super_blocks, s_list) { if (sb->s_syncing) continue;