/* Copyright (C) 2005-2009 Red Hat Inc. Copyright (C) 2006 Intel Corporation. This file is part of systemtap, and is free software. You can redistribute it and/or modify it under the terms of the GNU General Public License (GPL); either version 2, or (at your option) any later version. */ #ifndef _SYS_SDT_H #define _SYS_SDT_H 1 #include #include #if _LP64 #define STAP_PROBE_STRUCT_ARG(arg) \ __uint64_t arg #else #define STAP_PROBE_STRUCT_ARG(arg) \ long arg __attribute__ ((aligned(8))) #endif #define STAP_SENTINEL 0x31425250 #define STAP_PROBE_STRUCT(probe,argc) \ struct _probe_ ## probe \ { \ int probe_type; \ STAP_PROBE_STRUCT_ARG (probe_name); \ STAP_PROBE_STRUCT_ARG (probe_arg); \ }; \ static char probe ## _ ## probe_name [strlen(#probe)+1] \ __attribute__ ((section (".probes"))) \ = #probe; \ static volatile struct _probe_ ## probe _probe_ ## probe __attribute__ ((section (".probes"))) = {STAP_SENTINEL,(size_t)& probe ## _ ## probe_name[0],argc}; /* The goto _probe_ prevents the label from "drifting" */ #define STAP_LABEL_REF(probe, label) \ if (__builtin_expect(_probe_ ## probe.probe_type < 0, 0)) \ goto label /* These baroque macros are used to create a unique label */ #define STAP_CONCAT(a,b) a ## b #define STAP_LABEL_PREFIX(p) _stapprobe1_ ## p /* __COUNTER__ is not present in gcc 4.1 */ #if __GNUC__ == 4 && __GNUC_MINOR__ >= 3 #define STAP_COUNTER STAP_CONCAT(__,COUNTER__) #else #define STAP_COUNTER STAP_CONCAT(__,LINE__) #endif #define STAP_LABEL(a,b) STAP_CONCAT(a,b) #define STAP_PROBE_(probe,label) \ do { \ label: \ asm volatile ("nop"); \ STAP_PROBE_STRUCT(probe,(size_t)&& label) \ STAP_LABEL_REF(probe,label);} while (0) #define STAP_PROBE1_(probe,label,parm1) \ do { \ volatile typeof((parm1)) arg1 __attribute__ ((unused)); \ STAP_PROBE_STRUCT(probe,(size_t)&& label) \ STAP_LABEL_REF(probe,label); \ arg1 = parm1; \ label: \ asm volatile ("nop /* %0 */" :: "X"( arg1)); } while (0) #define STAP_PROBE2_(probe,label,parm1,parm2) \ do { \ volatile typeof((parm1)) arg1 __attribute__ ((unused)); \ volatile typeof((parm2)) arg2 __attribute__ ((unused)); \ STAP_PROBE_STRUCT(probe,(size_t)&& label) \ STAP_LABEL_REF(probe,label); \ arg1 = parm1; \ arg2 = parm2; \ label: \ asm volatile ("nop /* %0 %1 */" :: "X"(arg1), "X"(arg2)); } while (0) #define STAP_PROBE3_(probe,label,parm1,parm2,parm3) \ do { \ volatile typeof((parm1)) arg1 __attribute__ ((unused)); \ volatile typeof((parm2)) arg2 __attribute__ ((unused)); \ volatile typeof((parm3)) arg3 __attribute__ ((unused)); \ STAP_PROBE_STRUCT(probe,(size_t)&& label) \ STAP_LABEL_REF(probe,label); \ arg1 = parm1; \ arg2 = parm2; \ arg3 = parm3; \ label: \ asm volatile ("nop /* %0 %1 %2 */" :: "X"(arg1), "X"(arg2), "X"(arg3)); } while (0) #define STAP_PROBE4_(probe,label,parm1,parm2,parm3,parm4) \ do { \ volatile typeof((parm1)) arg1 __attribute__ ((unused)); \ volatile typeof((parm2)) arg2 __attribute__ ((unused)); \ volatile typeof((parm3)) arg3 __attribute__ ((unused)); \ volatile typeof((parm4)) arg4 __attribute__ ((unused)); \ STAP_PROBE_STRUCT(probe,(size_t)&& label) \ STAP_LABEL_REF(probe,label); \ arg1 = parm1; \ arg2 = parm2; \ arg3 = parm3; \ arg4 = parm4; \ label: \ asm volatile ("nop /* %0 %1 %2 %3 */" :: "X"(arg1), "X"(arg2), "X"(arg3), "X"(arg4)); } while (0) #define STAP_PROBE5_(probe,label,parm1,parm2,parm3,parm4,parm5) \ do { \ volatile typeof((parm1)) arg1 __attribute__ ((unused)); \ volatile typeof((parm2)) arg2 __attribute__ ((unused)); \ volatile typeof((parm3)) arg3 __attribute__ ((unused)); \ volatile typeof((parm4)) arg4 __attribute__ ((unused)); \ volatile typeof((parm5)) arg5 __attribute__ ((unused)); \ STAP_PROBE_STRUCT(probe,(size_t)&& label) \ STAP_LABEL_REF(probe,label); \ arg1 = parm1; \ arg2 = parm2; \ arg3 = parm3; \ arg4 = parm4; \ arg5 = parm5; \ label: \ asm volatile ("nop /* %0 %1 %2 %3 %4 */" :: "X"(arg1), "X"(arg2), "X"(arg3), "X"(arg4), "X"(arg5)); } while (0) #define STAP_PROBE6_(probe,label,parm1,parm2,parm3,parm4,parm5,parm6) \ do { \ volatile typeof((parm1)) arg1 __attribute__ ((unused)); \ volatile typeof((parm2)) arg2 __attribute__ ((unused)); \ volatile typeof((parm3)) arg3 __attribute__ ((unused)); \ volatile typeof((parm4)) arg4 __attribute__ ((unused)); \ volatile typeof((parm5)) arg5 __attribute__ ((unused)); \ volatile typeof((parm6)) arg6 __attribute__ ((unused)); \ STAP_PROBE_STRUCT(probe,(size_t)&& label) \ STAP_LABEL_REF(probe,label); \ arg1 = parm1; \ arg2 = parm2; \ arg3 = parm3; \ arg4 = parm4; \ arg5 = parm5; \ arg6 = parm6; \ label: \ asm volatile ("nop" :: "X"(arg1), "X"(arg2), "X"(arg3), "X"(arg4), "X"(arg5), "X"(arg6)); } while (0) #define STAP_PROBE7_(probe,label,parm1,parm2,parm3,parm4,parm5,parm6,parm7) \ do { \ volatile typeof((parm1)) arg1 __attribute__ ((unused)); \ volatile typeof((parm2)) arg2 __attribute__ ((unused)); \ volatile typeof((parm3)) arg3 __attribute__ ((unused)); \ volatile typeof((parm4)) arg4 __attribute__ ((unused)); \ volatile typeof((parm5)) arg5 __attribute__ ((unused)); \ volatile typeof((parm6)) arg6 __attribute__ ((unused)); \ volatile typeof((parm7)) arg7 __attribute__ ((unused)); \ STAP_PROBE_STRUCT(probe,(size_t)&& label) \ STAP_LABEL_REF(probe,label); \ arg1 = parm1; \ arg2 = parm2; \ arg3 = parm3; \ arg4 = parm4; \ arg5 = parm5; \ arg6 = parm6; \ arg7 = parm7; \ label: \ asm volatile ("nop" :: "X"(arg1), "X"(arg2), "X"(arg3), "X"(arg4), "X"(arg5), "X"(arg6), "X"(arg7)); } while (0) #define STAP_PROBE8_(probe,label,parm1,parm2,parm3,parm4,parm5,parm6,parm7,parm8) \ do { \ volatile typeof((parm1)) arg1 __attribute__ ((unused)); \ volatile typeof((parm2)) arg2 __attribute__ ((unused)); \ volatile typeof((parm3)) arg3 __attribute__ ((unused)); \ volatile typeof((parm4)) arg4 __attribute__ ((unused)); \ volatile typeof((parm5)) arg5 __attribute__ ((unused)); \ volatile typeof((parm6)) arg6 __attribute__ ((unused)); \ volatile typeof((parm7)) arg7 __attribute__ ((unused)); \ volatile typeof((parm8)) arg8 __attribute__ ((unused)); \ STAP_PROBE_STRUCT(probe,(size_t)&& label) \ STAP_LABEL_REF(probe,label); \ arg1 = parm1; \ arg2 = parm2; \ arg3 = parm3; \ arg4 = parm4; \ arg5 = parm5; \ arg6 = parm6; \ arg7 = parm7; \ arg8 = parm8; \ label: \ asm volatile ("nop" :: "X"(arg1), "X"(arg2), "X"(arg3), "X"(arg4), "X"(arg5), "X"(arg6), "X"(arg7), "X"(arg8)); } while (0) #define STAP_PROBE9_(probe,label,parm1,parm2,parm3,parm4,parm5,parm6,parm7,parm8,parm9) \ do { \ volatile typeof((parm1)) arg1 __attribute__ ((unused)); \ volatile typeof((parm2)) arg2 __attribute__ ((unused)); \ volatile typeof((parm3)) arg3 __attribute__ ((unused)); \ volatile typeof((parm4)) arg4 __attribute__ ((unused)); \ volatile typeof((parm5)) arg5 __attribute__ ((unused)); \ volatile typeof((parm6)) arg6 __attribute__ ((unused)); \ volatile typeof((parm7)) arg7 __attribute__ ((unused)); \ volatile typeof((parm8)) arg8 __attribute__ ((unused)); \ volatile typeof((parm9)) arg9 __attribute__ ((unused)); \ STAP_PROBE_STRUCT(probe,(size_t)&& label) \ STAP_LABEL_REF(probe,label); \ arg1 = parm1; \ arg2 = parm2; \ arg3 = parm3; \ arg4 = parm4; \ arg5 = parm5; \ arg6 = parm6; \ arg7 = parm7; \ arg8 = parm8; \ arg9 = parm9; \ label: \ asm volatile ("nop" :: "X"(arg1), "X"(arg2), "X"(arg3), "X"(arg4), "X"(arg5), "X"(arg6), "X"(arg7), "X"(arg8), "X"(arg9)); } while (0) #define STAP_PROBE10_(probe,label,parm1,parm2,parm3,parm4,parm5,parm6,parm7,parm8,parm9,parm10) \ do { \ volatile typeof((parm1)) arg1 __attribute__ ((unused)); \ volatile typeof((parm2)) arg2 __attribute__ ((unused)); \ volatile typeof((parm3)) arg3 __attribute__ ((unused)); \ volatile typeof((parm4)) arg4 __attribute__ ((unused)); \ volatile typeof((parm5)) arg5 __attribute__ ((unused)); \ volatile typeof((parm6)) arg6 __attribute__ ((unused)); \ volatile typeof((parm7)) arg7 __attribute__ ((unused)); \ volatile typeof((parm8)) arg8 __attribute__ ((unused)); \ volatile typeof((parm9)) arg9 __attribute__ ((unused)); \ volatile typeof((parm10)) arg10 __attribute__ ((unused)); \ STAP_PROBE_STRUCT(probe,(size_t)&& label) \ STAP_LABEL_REF(probe,label); \ arg1 = parm1; \ arg2 = parm2; \ arg3 = parm3; \ arg4 = parm4; \ arg5 = parm5; \ arg6 = parm6; \ arg7 = parm7; \ arg8 = parm8; \ arg9 = parm9; \ arg10 = parm10; \ label: \ asm volatile ("nop" :: "X"(arg1), "X"(arg2), "X"(arg3), "X"(arg4), "X"(arg5), "X"(arg6), "X"(arg7), "X"(arg8), "X"(arg9), "X"(arg10)); } while (0) #define STAP_PROBE(provider,probe) \ STAP_PROBE_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER)) #define STAP_PROBE1(provider,probe,...) \ STAP_PROBE1_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER),__VA_ARGS__) #define STAP_PROBE2(provider,probe,...) \ STAP_PROBE2_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER),__VA_ARGS__) #define STAP_PROBE3(provider,probe,...) \ STAP_PROBE3_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER),__VA_ARGS__) #define STAP_PROBE4(provider,probe,...) \ STAP_PROBE4_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER),__VA_ARGS__) #define STAP_PROBE5(provider,probe,...) \ STAP_PROBE5_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER),__VA_ARGS__) #define STAP_PROBE6(provider,probe,...) \ STAP_PROBE6_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER),__VA_ARGS__) #define STAP_PROBE7(provider,probe,...) \ STAP_PROBE7_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER),__VA_ARGS__) #define STAP_PROBE8(provider,probe,...) \ STAP_PROBE8_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER),__VA_ARGS__) #define STAP_PROBE9(provider,probe,...) \ STAP_PROBE9_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER),__VA_ARGS__) #define STAP_PROBE10(provider,probe,...) \ STAP_PROBE10_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER),__VA_ARGS__) #define DTRACE_PROBE(provider,probe) \ STAP_PROBE(provider,probe) #define DTRACE_PROBE1(provider,probe,parm1) \ STAP_PROBE1(provider,probe,parm1) #define DTRACE_PROBE2(provider,probe,parm1,parm2) \ STAP_PROBE2(provider,probe,parm1,parm2) #define DTRACE_PROBE3(provider,probe,parm1,parm2,parm3) \ STAP_PROBE3(provider,probe,parm1,parm2,parm3) #define DTRACE_PROBE4(provider,probe,parm1,parm2,parm3,parm4) \ STAP_PROBE4(provider,probe,parm1,parm2,parm3,parm4) #define DTRACE_PROBE5(provider,probe,parm1,parm2,parm3,parm4,parm5) \ STAP_PROBE5(provider,probe,parm1,parm2,parm3,parm4,parm5) #define DTRACE_PROBE6(provider,probe,parm1,parm2,parm3,parm4,parm5,parm6) \ STAP_PROBE6(provider,probe,parm1,parm2,parm3,parm4,parm5,parm6) #define DTRACE_PROBE7(provider,probe,parm1,parm2,parm3,parm4,parm5,parm6,parm7) \ STAP_PROBE7(provider,probe,parm1,parm2,parm3,parm4,parm5,parm6,parm7) #define DTRACE_PROBE8(provider,probe,parm1,parm2,parm3,parm4,parm5,parm6,parm7,parm8) \ STAP_PROBE8(provider,probe,parm1,parm2,parm3,parm4,parm5,parm6,parm7,parm8) #define DTRACE_PROBE9(provider,probe,parm1,parm2,parm3,parm4,parm5,parm6,parm7,parm8,parm9) \ STAP_PROBE9(provider,probe,parm1,parm2,parm3,parm4,parm5,parm6,parm7,parm8,parm9) #endif /* sys/sdt.h */ n223' href='#n223'>223 224 225 226 227 228 229 230 231 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/*
 * linux/fs/inode.c
 *
 * (C) 1997 Linus Torvalds
 */

#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/dcache.h>
#include <linux/init.h>
#include <linux/quotaops.h>
#include <linux/slab.h>
#include <linux/writeback.h>
#include <linux/module.h>
#include <linux/backing-dev.h>
#include <linux/wait.h>
#include <linux/hash.h>
#include <linux/swap.h>
#include <linux/security.h>
#include <linux/pagemap.h>
#include <linux/cdev.h>
#include <linux/bootmem.h>
#include <linux/inotify.h>
#include <linux/mount.h>

/*
 * This is needed for the following functions:
 *  - inode_has_buffers
 *  - invalidate_inode_buffers
 *  - invalidate_bdev
 *
 * FIXME: remove all knowledge of the buffer layer from this file
 */
#include <linux/buffer_head.h>

/*
 * New inode.c implementation.
 *
 * This implementation has the basic premise of trying
 * to be extremely low-overhead and SMP-safe, yet be
 * simple enough to be "obviously correct".
 *
 * Famous last words.
 */

/* inode dynamic allocation 1999, Andrea Arcangeli <andrea@suse.de> */

/* #define INODE_PARANOIA 1 */
/* #define INODE_DEBUG 1 */

/*
 * Inode lookup is no longer as critical as it used to be:
 * most of the lookups are going to be through the dcache.
 */
#define I_HASHBITS	i_hash_shift
#define I_HASHMASK	i_hash_mask

static unsigned int i_hash_mask __read_mostly;
static unsigned int i_hash_shift __read_mostly;

/*
 * Each inode can be on two separate lists. One is
 * the hash list of the inode, used for lookups. The
 * other linked list is the "type" list:
 *  "in_use" - valid inode, i_count > 0, i_nlink > 0
 *  "dirty"  - as "in_use" but also dirty
 *  "unused" - valid inode, i_count = 0
 *
 * A "dirty" list is maintained for each super block,
 * allowing for low-overhead inode sync() operations.
 */

LIST_HEAD(inode_in_use);
LIST_HEAD(inode_unused);
static struct hlist_head *inode_hashtable __read_mostly;

/*
 * A simple spinlock to protect the list manipulations.
 *
 * NOTE! You also have to own the lock if you change
 * the i_state of an inode while it is in use..
 */
DEFINE_SPINLOCK(inode_lock);

/*
 * iprune_mutex provides exclusion between the kswapd or try_to_free_pages
 * icache shrinking path, and the umount path.  Without this exclusion,
 * by the time prune_icache calls iput for the inode whose pages it has
 * been invalidating, or by the time it calls clear_inode & destroy_inode
 * from its final dispose_list, the struct super_block they refer to
 * (for inode->i_sb->s_op) may already have been freed and reused.
 */
static DEFINE_MUTEX(iprune_mutex);

/*
 * Statistics gathering..
 */
struct inodes_stat_t inodes_stat;

static struct kmem_cache * inode_cachep __read_mostly;

static struct inode *alloc_inode(struct super_block *sb)
{
	static const struct address_space_operations empty_aops;
	static struct inode_operations empty_iops;
	static const struct file_operations empty_fops;
	struct inode *inode;

	if (sb->s_op->alloc_inode)
		inode = sb->s_op->alloc_inode(sb);
	else
		inode = (struct inode *) kmem_cache_alloc(inode_cachep, GFP_KERNEL);

	if (inode) {
		struct address_space * const mapping = &inode->i_data;

		inode->i_sb = sb;
		inode->i_blkbits = sb->s_blocksize_bits;
		inode->i_flags = 0;
		atomic_set(&inode->i_count, 1);
		inode->i_op = &empty_iops;
		inode->i_fop = &empty_fops;
		inode->i_nlink = 1;
		atomic_set(&inode->i_writecount, 0);
		inode->i_size = 0;
		inode->i_blocks = 0;
		inode->i_bytes = 0;
		inode->i_generation = 0;
#ifdef CONFIG_QUOTA
		memset(&inode->i_dquot, 0, sizeof(inode->i_dquot));
#endif
		inode->i_pipe = NULL;
		inode->i_bdev = NULL;
		inode->i_cdev = NULL;
		inode->i_rdev = 0;
		inode->dirtied_when = 0;
		if (security_inode_alloc(inode)) {
			if (inode->i_sb->s_op->destroy_inode)
				inode->i_sb->s_op->destroy_inode(inode);
			else
				kmem_cache_free(inode_cachep, (inode));
			return NULL;
		}

		mapping->a_ops = &empty_aops;
 		mapping->host = inode;
		mapping->flags = 0;
		mapping_set_gfp_mask(mapping, GFP_HIGHUSER_PAGECACHE);
		mapping->assoc_mapping = NULL;
		mapping->backing_dev_info = &default_backing_dev_info;

		/*
		 * If the block_device provides a backing_dev_info for client
		 * inodes then use that.  Otherwise the inode share the bdev's
		 * backing_dev_info.
		 */
		if (sb->s_bdev) {
			struct backing_dev_info *bdi;

			bdi = sb->s_bdev->bd_inode_backing_dev_info;
			if (!bdi)
				bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info;
			mapping->backing_dev_info = bdi;
		}
		inode->i_private = NULL;
		inode->i_mapping = mapping;
	}
	return inode;
}

void destroy_inode(struct inode *inode) 
{
	BUG_ON(inode_has_buffers(inode));
	security_inode_free(inode);
	if (inode->i_sb->s_op->destroy_inode)
		inode->i_sb->s_op->destroy_inode(inode);
	else
		kmem_cache_free(inode_cachep, (inode));
}


/*
 * These are initializations that only need to be done
 * once, because the fields are idempotent across use
 * of the inode, so let the slab aware of that.
 */
void inode_init_once(struct inode *inode)
{
	memset(inode, 0, sizeof(*inode));
	INIT_HLIST_NODE(&inode->i_hash);
	INIT_LIST_HEAD(&inode->i_dentry);
	INIT_LIST_HEAD(&inode->i_devices);
	mutex_init(&inode->i_mutex);
	init_rwsem(&inode->i_alloc_sem);
	INIT_RADIX_TREE(&inode->i_data.page_tree, GFP_ATOMIC);
	rwlock_init(&inode->i_data.tree_lock);
	spin_lock_init(&inode->i_data.i_mmap_lock);
	INIT_LIST_HEAD(&inode->i_data.private_list);
	spin_lock_init(&inode->i_data.private_lock);
	INIT_RAW_PRIO_TREE_ROOT(&inode->i_data.i_mmap);
	INIT_LIST_HEAD(&inode->i_data.i_mmap_nonlinear);
	spin_lock_init(&inode->i_lock);
	i_size_ordered_init(inode);
#ifdef CONFIG_INOTIFY
	INIT_LIST_HEAD(&inode->inotify_watches);
	mutex_init(&inode->inotify_mutex);
#endif
}

EXPORT_SYMBOL(inode_init_once);

static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags)
{
	struct inode * inode = (struct inode *) foo;

	inode_init_once(inode);
}

/*
 * inode_lock must be held
 */
void __iget(struct inode * inode)
{
	if (atomic_read(&inode->i_count)) {
		atomic_inc(&inode->i_count);
		return;
	}
	atomic_inc(&inode->i_count);
	if (!(inode->i_state & (I_DIRTY|I_LOCK)))
		list_move(&inode->i_list, &inode_in_use);
	inodes_stat.nr_unused--;
}

/**
 * clear_inode - clear an inode
 * @inode: inode to clear
 *
 * This is called by the filesystem to tell us
 * that the inode is no longer useful. We just
 * terminate it with extreme prejudice.
 */
void clear_inode(struct inode *inode)
{
	might_sleep();
	invalidate_inode_buffers(inode);
       
	BUG_ON(inode->i_data.nrpages);
	BUG_ON(!(inode->i_state & I_FREEING));
	BUG_ON(inode->i_state & I_CLEAR);
	wait_on_inode(inode);
	DQUOT_DROP(inode);
	if (inode->i_sb->s_op->clear_inode)
		inode->i_sb->s_op->clear_inode(inode);
	if (S_ISBLK(inode->i_mode) && inode->i_bdev)
		bd_forget(inode);
	if (S_ISCHR(inode->i_mode) && inode->i_cdev)
		cd_forget(inode);
	inode->i_state = I_CLEAR;
}

EXPORT_SYMBOL(clear_inode);

/*
 * dispose_list - dispose of the contents of a local list
 * @head: the head of the list to free
 *
 * Dispose-list gets a local list with local inodes in it, so it doesn't
 * need to worry about list corruption and SMP locks.
 */
static void dispose_list(struct list_head *head)
{
	int nr_disposed = 0;

	while (!list_empty(head)) {
		struct inode *inode;

		inode = list_first_entry(head, struct inode, i_list);
		list_del(&inode->i_list);

		if (inode->i_data.nrpages)
			truncate_inode_pages(&inode->i_data, 0);
		clear_inode(inode);

		spin_lock(&inode_lock);
		hlist_del_init(&inode->i_hash);
		list_del_init(&inode->i_sb_list);
		spin_unlock(&inode_lock);

		wake_up_inode(inode);
		destroy_inode(inode);
		nr_disposed++;
	}
	spin_lock(&inode_lock);
	inodes_stat.nr_inodes -= nr_disposed;
	spin_unlock(&inode_lock);
}

/*
 * Invalidate all inodes for a device.
 */
static int invalidate_list(struct list_head *head, struct list_head *dispose)
{
	struct list_head *next;
	int busy = 0, count = 0;

	next = head->next;
	for (;;) {