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fs/inode.c
48.7 KB
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/* |
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* (C) 1997 Linus Torvalds |
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* (C) 1999 Andrea Arcangeli <andrea@suse.de> (dynamic inode allocation) |
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*/ |
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#include <linux/export.h> |
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#include <linux/fs.h> #include <linux/mm.h> |
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#include <linux/backing-dev.h> |
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#include <linux/hash.h> #include <linux/swap.h> #include <linux/security.h> |
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#include <linux/cdev.h> #include <linux/bootmem.h> |
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#include <linux/fsnotify.h> |
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#include <linux/mount.h> |
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#include <linux/posix_acl.h> |
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#include <linux/prefetch.h> |
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#include <linux/buffer_head.h> /* for inode_has_buffers */ |
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#include <linux/ratelimit.h> |
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#include "internal.h" |
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/* |
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* Inode locking rules: |
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* * inode->i_lock protects: * inode->i_state, inode->i_hash, __iget() |
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* inode->i_sb->s_inode_lru_lock protects: |
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* inode->i_sb->s_inode_lru, inode->i_lru |
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* inode_sb_list_lock protects: * sb->s_inodes, inode->i_sb_list |
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* bdi->wb.list_lock protects: |
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* bdi->wb.b_{dirty,io,more_io}, inode->i_wb_list |
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* inode_hash_lock protects: * inode_hashtable, inode->i_hash |
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* * Lock ordering: |
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* * inode_sb_list_lock * inode->i_lock |
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* inode->i_sb->s_inode_lru_lock |
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* |
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* bdi->wb.list_lock |
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* inode->i_lock |
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* * inode_hash_lock * inode_sb_list_lock * inode->i_lock * * iunique_lock * inode_hash_lock |
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*/ |
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static unsigned int i_hash_mask __read_mostly; static unsigned int i_hash_shift __read_mostly; |
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static struct hlist_head *inode_hashtable __read_mostly; static __cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_hash_lock); |
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|
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__cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_sb_list_lock); |
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/* |
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* Empty aops. Can be used for the cases where the user does not * define any of the address_space operations. */ const struct address_space_operations empty_aops = { }; EXPORT_SYMBOL(empty_aops); /* |
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* Statistics gathering.. */ struct inodes_stat_t inodes_stat; |
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static DEFINE_PER_CPU(unsigned int, nr_inodes); |
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static DEFINE_PER_CPU(unsigned int, nr_unused); |
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|
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static struct kmem_cache *inode_cachep __read_mostly; |
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|
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static int get_nr_inodes(void) |
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{ |
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int i; int sum = 0; for_each_possible_cpu(i) sum += per_cpu(nr_inodes, i); return sum < 0 ? 0 : sum; |
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} static inline int get_nr_inodes_unused(void) { |
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int i; int sum = 0; for_each_possible_cpu(i) sum += per_cpu(nr_unused, i); return sum < 0 ? 0 : sum; |
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} int get_nr_dirty_inodes(void) { |
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/* not actually dirty inodes, but a wild approximation */ |
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int nr_dirty = get_nr_inodes() - get_nr_inodes_unused(); return nr_dirty > 0 ? nr_dirty : 0; |
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} /* * Handle nr_inode sysctl */ #ifdef CONFIG_SYSCTL int proc_nr_inodes(ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { inodes_stat.nr_inodes = get_nr_inodes(); |
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inodes_stat.nr_unused = get_nr_inodes_unused(); |
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return proc_dointvec(table, write, buffer, lenp, ppos); } #endif |
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/** * inode_init_always - perform inode structure intialisation |
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* @sb: superblock inode belongs to * @inode: inode to initialise |
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* * These are initializations that need to be done on every inode * allocation as the fields are not initialised by slab allocation. */ |
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int inode_init_always(struct super_block *sb, struct inode *inode) |
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{ |
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static const struct inode_operations empty_iops; |
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static const struct file_operations empty_fops; |
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struct address_space *const mapping = &inode->i_data; |
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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; |
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inode->__i_nlink = 1; |
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inode->i_opflags = 0; |
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i_uid_write(inode, 0); i_gid_write(inode, 0); |
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atomic_set(&inode->i_writecount, 0); inode->i_size = 0; inode->i_blocks = 0; inode->i_bytes = 0; inode->i_generation = 0; |
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#ifdef CONFIG_QUOTA |
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memset(&inode->i_dquot, 0, sizeof(inode->i_dquot)); |
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#endif |
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inode->i_pipe = NULL; inode->i_bdev = NULL; inode->i_cdev = NULL; inode->i_rdev = 0; inode->dirtied_when = 0; |
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if (security_inode_alloc(inode)) |
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goto out; |
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spin_lock_init(&inode->i_lock); lockdep_set_class(&inode->i_lock, &sb->s_type->i_lock_key); mutex_init(&inode->i_mutex); lockdep_set_class(&inode->i_mutex, &sb->s_type->i_mutex_key); |
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atomic_set(&inode->i_dio_count, 0); |
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mapping->a_ops = &empty_aops; mapping->host = inode; mapping->flags = 0; |
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mapping_set_gfp_mask(mapping, GFP_HIGHUSER_MOVABLE); |
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mapping->private_data = NULL; |
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mapping->backing_dev_info = &default_backing_dev_info; mapping->writeback_index = 0; /* * 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; |
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bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info; |
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mapping->backing_dev_info = bdi; } inode->i_private = NULL; inode->i_mapping = mapping; |
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INIT_HLIST_HEAD(&inode->i_dentry); /* buggered by rcu freeing */ |
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#ifdef CONFIG_FS_POSIX_ACL inode->i_acl = inode->i_default_acl = ACL_NOT_CACHED; #endif |
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|
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#ifdef CONFIG_FSNOTIFY inode->i_fsnotify_mask = 0; #endif |
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this_cpu_inc(nr_inodes); |
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|
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return 0; |
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out: return -ENOMEM; |
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} |
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EXPORT_SYMBOL(inode_init_always); static struct inode *alloc_inode(struct super_block *sb) { struct inode *inode; if (sb->s_op->alloc_inode) inode = sb->s_op->alloc_inode(sb); else inode = kmem_cache_alloc(inode_cachep, GFP_KERNEL); |
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if (!inode) return NULL; if (unlikely(inode_init_always(sb, 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; } return inode; |
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} |
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void free_inode_nonrcu(struct inode *inode) { kmem_cache_free(inode_cachep, inode); } EXPORT_SYMBOL(free_inode_nonrcu); |
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void __destroy_inode(struct inode *inode) |
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{ |
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BUG_ON(inode_has_buffers(inode)); |
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security_inode_free(inode); |
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fsnotify_inode_delete(inode); |
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if (!inode->i_nlink) { WARN_ON(atomic_long_read(&inode->i_sb->s_remove_count) == 0); atomic_long_dec(&inode->i_sb->s_remove_count); } |
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#ifdef CONFIG_FS_POSIX_ACL if (inode->i_acl && inode->i_acl != ACL_NOT_CACHED) posix_acl_release(inode->i_acl); if (inode->i_default_acl && inode->i_default_acl != ACL_NOT_CACHED) posix_acl_release(inode->i_default_acl); #endif |
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this_cpu_dec(nr_inodes); |
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} EXPORT_SYMBOL(__destroy_inode); |
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static void i_callback(struct rcu_head *head) { struct inode *inode = container_of(head, struct inode, i_rcu); |
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kmem_cache_free(inode_cachep, inode); } |
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static void destroy_inode(struct inode *inode) |
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{ |
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BUG_ON(!list_empty(&inode->i_lru)); |
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__destroy_inode(inode); |
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if (inode->i_sb->s_op->destroy_inode) inode->i_sb->s_op->destroy_inode(inode); else |
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call_rcu(&inode->i_rcu, i_callback); |
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} |
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/** * drop_nlink - directly drop an inode's link count * @inode: inode * * This is a low-level filesystem helper to replace any * direct filesystem manipulation of i_nlink. In cases * where we are attempting to track writes to the * filesystem, a decrement to zero means an imminent * write when the file is truncated and actually unlinked * on the filesystem. */ void drop_nlink(struct inode *inode) { WARN_ON(inode->i_nlink == 0); inode->__i_nlink--; if (!inode->i_nlink) atomic_long_inc(&inode->i_sb->s_remove_count); } EXPORT_SYMBOL(drop_nlink); /** * clear_nlink - directly zero an inode's link count * @inode: inode * * This is a low-level filesystem helper to replace any * direct filesystem manipulation of i_nlink. See * drop_nlink() for why we care about i_nlink hitting zero. */ void clear_nlink(struct inode *inode) { if (inode->i_nlink) { inode->__i_nlink = 0; atomic_long_inc(&inode->i_sb->s_remove_count); } } EXPORT_SYMBOL(clear_nlink); /** * set_nlink - directly set an inode's link count * @inode: inode * @nlink: new nlink (should be non-zero) * * This is a low-level filesystem helper to replace any * direct filesystem manipulation of i_nlink. */ void set_nlink(struct inode *inode, unsigned int nlink) { if (!nlink) { |
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clear_nlink(inode); } else { /* Yes, some filesystems do change nlink from zero to one */ if (inode->i_nlink == 0) atomic_long_dec(&inode->i_sb->s_remove_count); inode->__i_nlink = nlink; } } EXPORT_SYMBOL(set_nlink); /** * inc_nlink - directly increment an inode's link count * @inode: inode * * This is a low-level filesystem helper to replace any * direct filesystem manipulation of i_nlink. Currently, * it is only here for parity with dec_nlink(). */ void inc_nlink(struct inode *inode) { if (WARN_ON(inode->i_nlink == 0)) atomic_long_dec(&inode->i_sb->s_remove_count); inode->__i_nlink++; } EXPORT_SYMBOL(inc_nlink); |
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void address_space_init_once(struct address_space *mapping) { memset(mapping, 0, sizeof(*mapping)); INIT_RADIX_TREE(&mapping->page_tree, GFP_ATOMIC); spin_lock_init(&mapping->tree_lock); |
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mutex_init(&mapping->i_mmap_mutex); |
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INIT_LIST_HEAD(&mapping->private_list); spin_lock_init(&mapping->private_lock); |
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mapping->i_mmap = RB_ROOT; |
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INIT_LIST_HEAD(&mapping->i_mmap_nonlinear); |
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} EXPORT_SYMBOL(address_space_init_once); |
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/* * 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); |
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INIT_LIST_HEAD(&inode->i_devices); |
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INIT_LIST_HEAD(&inode->i_wb_list); INIT_LIST_HEAD(&inode->i_lru); |
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address_space_init_once(&inode->i_data); |
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i_size_ordered_init(inode); |
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#ifdef CONFIG_FSNOTIFY |
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INIT_HLIST_HEAD(&inode->i_fsnotify_marks); |
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#endif |
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} |
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EXPORT_SYMBOL(inode_init_once); |
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static void init_once(void *foo) |
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{ |
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struct inode *inode = (struct inode *) foo; |
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|
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inode_init_once(inode); |
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} /* |
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* inode->i_lock must be held |
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*/ |
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void __iget(struct inode *inode) |
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{ |
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atomic_inc(&inode->i_count); } |
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|
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/* * get additional reference to inode; caller must already hold one. */ void ihold(struct inode *inode) { WARN_ON(atomic_inc_return(&inode->i_count) < 2); } EXPORT_SYMBOL(ihold); |
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static void inode_lru_list_add(struct inode *inode) { |
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spin_lock(&inode->i_sb->s_inode_lru_lock); |
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if (list_empty(&inode->i_lru)) { |
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list_add(&inode->i_lru, &inode->i_sb->s_inode_lru); inode->i_sb->s_nr_inodes_unused++; |
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this_cpu_inc(nr_unused); |
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} |
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spin_unlock(&inode->i_sb->s_inode_lru_lock); |
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} |
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/* * Add inode to LRU if needed (inode is unused and clean). * * Needs inode->i_lock held. */ void inode_add_lru(struct inode *inode) { if (!(inode->i_state & (I_DIRTY | I_SYNC | I_FREEING | I_WILL_FREE)) && !atomic_read(&inode->i_count) && inode->i_sb->s_flags & MS_ACTIVE) inode_lru_list_add(inode); } |
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static void inode_lru_list_del(struct inode *inode) { |
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spin_lock(&inode->i_sb->s_inode_lru_lock); |
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if (!list_empty(&inode->i_lru)) { list_del_init(&inode->i_lru); |
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inode->i_sb->s_nr_inodes_unused--; |
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this_cpu_dec(nr_unused); |
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} |
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spin_unlock(&inode->i_sb->s_inode_lru_lock); |
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} |
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/** * inode_sb_list_add - add inode to the superblock list of inodes * @inode: inode to add */ void inode_sb_list_add(struct inode *inode) { |
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spin_lock(&inode_sb_list_lock); list_add(&inode->i_sb_list, &inode->i_sb->s_inodes); spin_unlock(&inode_sb_list_lock); |
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} EXPORT_SYMBOL_GPL(inode_sb_list_add); |
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static inline void inode_sb_list_del(struct inode *inode) |
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{ |
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if (!list_empty(&inode->i_sb_list)) { spin_lock(&inode_sb_list_lock); list_del_init(&inode->i_sb_list); spin_unlock(&inode_sb_list_lock); } |
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} |
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static unsigned long hash(struct super_block *sb, unsigned long hashval) { unsigned long tmp; tmp = (hashval * (unsigned long)sb) ^ (GOLDEN_RATIO_PRIME + hashval) / L1_CACHE_BYTES; |
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tmp = tmp ^ ((tmp ^ GOLDEN_RATIO_PRIME) >> i_hash_shift); return tmp & i_hash_mask; |
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} /** * __insert_inode_hash - hash an inode * @inode: unhashed inode * @hashval: unsigned long value used to locate this object in the * inode_hashtable. * * Add an inode to the inode hash for this superblock. */ void __insert_inode_hash(struct inode *inode, unsigned long hashval) { |
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struct hlist_head *b = inode_hashtable + hash(inode->i_sb, hashval); |
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spin_lock(&inode_hash_lock); |
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spin_lock(&inode->i_lock); |
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hlist_add_head(&inode->i_hash, b); |
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spin_unlock(&inode->i_lock); |
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spin_unlock(&inode_hash_lock); |
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} EXPORT_SYMBOL(__insert_inode_hash); /** |
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* __remove_inode_hash - remove an inode from the hash |
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* @inode: inode to unhash * * Remove an inode from the superblock. */ |
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void __remove_inode_hash(struct inode *inode) |
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{ |
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spin_lock(&inode_hash_lock); |
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spin_lock(&inode->i_lock); |
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hlist_del_init(&inode->i_hash); |
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spin_unlock(&inode->i_lock); |
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spin_unlock(&inode_hash_lock); |
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} |
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EXPORT_SYMBOL(__remove_inode_hash); |
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|
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void clear_inode(struct inode *inode) |
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{ might_sleep(); |
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/* * We have to cycle tree_lock here because reclaim can be still in the * process of removing the last page (in __delete_from_page_cache()) * and we must not free mapping under it. */ spin_lock_irq(&inode->i_data.tree_lock); |
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BUG_ON(inode->i_data.nrpages); |
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spin_unlock_irq(&inode->i_data.tree_lock); |
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BUG_ON(!list_empty(&inode->i_data.private_list)); BUG_ON(!(inode->i_state & I_FREEING)); BUG_ON(inode->i_state & I_CLEAR); |
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/* don't need i_lock here, no concurrent mods to i_state */ |
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495 496 |
inode->i_state = I_FREEING | I_CLEAR; } |
dbd5768f8
|
497 |
EXPORT_SYMBOL(clear_inode); |
b0683aa63
|
498 |
|
b2b2af8e6
|
499 500 501 502 503 504 505 506 507 508 509 510 511 |
/* * Free the inode passed in, removing it from the lists it is still connected * to. We remove any pages still attached to the inode and wait for any IO that * is still in progress before finally destroying the inode. * * An inode must already be marked I_FREEING so that we avoid the inode being * moved back onto lists if we race with other code that manipulates the lists * (e.g. writeback_single_inode). The caller is responsible for setting this. * * An inode must already be removed from the LRU list before being evicted from * the cache. This should occur atomically with setting the I_FREEING state * flag, so no inodes here should ever be on the LRU when being evicted. */ |
644da5960
|
512 |
static void evict(struct inode *inode) |
b4272d4c8
|
513 514 |
{ const struct super_operations *op = inode->i_sb->s_op; |
b2b2af8e6
|
515 516 |
BUG_ON(!(inode->i_state & I_FREEING)); BUG_ON(!list_empty(&inode->i_lru)); |
b12362bdb
|
517 518 |
if (!list_empty(&inode->i_wb_list)) inode_wb_list_del(inode); |
55fa6091d
|
519 |
inode_sb_list_del(inode); |
169ebd901
|
520 521 522 523 524 525 526 |
/* * Wait for flusher thread to be done with the inode so that filesystem * does not start destroying it while writeback is still running. Since * the inode has I_FREEING set, flusher thread won't start new work on * the inode. We just have to wait for running writeback to finish. */ inode_wait_for_writeback(inode); |
7994e6f72
|
527 |
|
be7ce4161
|
528 529 |
if (op->evict_inode) { op->evict_inode(inode); |
b4272d4c8
|
530 531 532 |
} else { if (inode->i_data.nrpages) truncate_inode_pages(&inode->i_data, 0); |
dbd5768f8
|
533 |
clear_inode(inode); |
b4272d4c8
|
534 |
} |
661074e91
|
535 536 537 538 |
if (S_ISBLK(inode->i_mode) && inode->i_bdev) bd_forget(inode); if (S_ISCHR(inode->i_mode) && inode->i_cdev) cd_forget(inode); |
b2b2af8e6
|
539 540 541 542 543 544 545 546 547 |
remove_inode_hash(inode); spin_lock(&inode->i_lock); wake_up_bit(&inode->i_state, __I_NEW); BUG_ON(inode->i_state != (I_FREEING | I_CLEAR)); spin_unlock(&inode->i_lock); destroy_inode(inode); |
b4272d4c8
|
548 |
} |
1da177e4c
|
549 550 551 552 553 554 555 556 557 |
/* * 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) { |
1da177e4c
|
558 559 |
while (!list_empty(head)) { struct inode *inode; |
7ccf19a80
|
560 561 |
inode = list_first_entry(head, struct inode, i_lru); list_del_init(&inode->i_lru); |
1da177e4c
|
562 |
|
644da5960
|
563 |
evict(inode); |
1da177e4c
|
564 |
} |
1da177e4c
|
565 |
} |
a03187867
|
566 |
/** |
63997e98a
|
567 568 569 570 571 572 573 |
* evict_inodes - evict all evictable inodes for a superblock * @sb: superblock to operate on * * Make sure that no inodes with zero refcount are retained. This is * called by superblock shutdown after having MS_ACTIVE flag removed, * so any inode reaching zero refcount during or after that call will * be immediately evicted. |
1da177e4c
|
574 |
*/ |
63997e98a
|
575 |
void evict_inodes(struct super_block *sb) |
1da177e4c
|
576 |
{ |
63997e98a
|
577 578 |
struct inode *inode, *next; LIST_HEAD(dispose); |
1da177e4c
|
579 |
|
55fa6091d
|
580 |
spin_lock(&inode_sb_list_lock); |
63997e98a
|
581 582 |
list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) { if (atomic_read(&inode->i_count)) |
aabb8fdb4
|
583 |
continue; |
250df6ed2
|
584 585 586 587 |
spin_lock(&inode->i_lock); if (inode->i_state & (I_NEW | I_FREEING | I_WILL_FREE)) { spin_unlock(&inode->i_lock); |
1da177e4c
|
588 |
continue; |
250df6ed2
|
589 |
} |
63997e98a
|
590 591 |
inode->i_state |= I_FREEING; |
02afc410f
|
592 |
inode_lru_list_del(inode); |
250df6ed2
|
593 |
spin_unlock(&inode->i_lock); |
02afc410f
|
594 |
list_add(&inode->i_lru, &dispose); |
1da177e4c
|
595 |
} |
55fa6091d
|
596 |
spin_unlock(&inode_sb_list_lock); |
63997e98a
|
597 598 |
dispose_list(&dispose); |
1da177e4c
|
599 |
} |
1da177e4c
|
600 |
/** |
a03187867
|
601 602 |
* invalidate_inodes - attempt to free all inodes on a superblock * @sb: superblock to operate on |
93b270f76
|
603 |
* @kill_dirty: flag to guide handling of dirty inodes |
1da177e4c
|
604 |
* |
a03187867
|
605 606 |
* Attempts to free all inodes for a given superblock. If there were any * busy inodes return a non-zero value, else zero. |
93b270f76
|
607 608 |
* If @kill_dirty is set, discard dirty inodes too, otherwise treat * them as busy. |
1da177e4c
|
609 |
*/ |
93b270f76
|
610 |
int invalidate_inodes(struct super_block *sb, bool kill_dirty) |
1da177e4c
|
611 |
{ |
cffbc8aa3
|
612 |
int busy = 0; |
a03187867
|
613 614 |
struct inode *inode, *next; LIST_HEAD(dispose); |
1da177e4c
|
615 |
|
55fa6091d
|
616 |
spin_lock(&inode_sb_list_lock); |
a03187867
|
617 |
list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) { |
250df6ed2
|
618 619 620 |
spin_lock(&inode->i_lock); if (inode->i_state & (I_NEW | I_FREEING | I_WILL_FREE)) { spin_unlock(&inode->i_lock); |
aabb8fdb4
|
621 |
continue; |
250df6ed2
|
622 |
} |
93b270f76
|
623 |
if (inode->i_state & I_DIRTY && !kill_dirty) { |
250df6ed2
|
624 |
spin_unlock(&inode->i_lock); |
93b270f76
|
625 626 627 |
busy = 1; continue; } |
99a389192
|
628 |
if (atomic_read(&inode->i_count)) { |
250df6ed2
|
629 |
spin_unlock(&inode->i_lock); |
99a389192
|
630 |
busy = 1; |
1da177e4c
|
631 632 |
continue; } |
99a389192
|
633 |
|
99a389192
|
634 |
inode->i_state |= I_FREEING; |
02afc410f
|
635 |
inode_lru_list_del(inode); |
250df6ed2
|
636 |
spin_unlock(&inode->i_lock); |
02afc410f
|
637 |
list_add(&inode->i_lru, &dispose); |
1da177e4c
|
638 |
} |
55fa6091d
|
639 |
spin_unlock(&inode_sb_list_lock); |
1da177e4c
|
640 |
|
a03187867
|
641 |
dispose_list(&dispose); |
1da177e4c
|
642 643 644 |
return busy; } |
1da177e4c
|
645 646 647 |
static int can_unuse(struct inode *inode) { |
9e38d86ff
|
648 |
if (inode->i_state & ~I_REFERENCED) |
1da177e4c
|
649 650 651 652 653 654 655 656 657 658 659 |
return 0; if (inode_has_buffers(inode)) return 0; if (atomic_read(&inode->i_count)) return 0; if (inode->i_data.nrpages) return 0; return 1; } /* |
b0d40c92a
|
660 661 662 663 |
* Walk the superblock inode LRU for freeable inodes and attempt to free them. * This is called from the superblock shrinker function with a number of inodes * to trim from the LRU. Inodes to be freed are moved to a temporary list and * then are freed outside inode_lock by dispose_list(). |
1da177e4c
|
664 665 |
* * Any inodes which are pinned purely because of attached pagecache have their |
9e38d86ff
|
666 667 |
* pagecache removed. If the inode has metadata buffers attached to * mapping->private_list then try to remove them. |
1da177e4c
|
668 |
* |
9e38d86ff
|
669 670 671 672 673 674 675 |
* If the inode has the I_REFERENCED flag set, then it means that it has been * used recently - the flag is set in iput_final(). When we encounter such an * inode, clear the flag and move it to the back of the LRU so it gets another * pass through the LRU before it gets reclaimed. This is necessary because of * the fact we are doing lazy LRU updates to minimise lock contention so the * LRU does not have strict ordering. Hence we don't want to reclaim inodes * with this flag set because they are the inodes that are out of order. |
1da177e4c
|
676 |
*/ |
b0d40c92a
|
677 |
void prune_icache_sb(struct super_block *sb, int nr_to_scan) |
1da177e4c
|
678 679 |
{ LIST_HEAD(freeable); |
1da177e4c
|
680 681 |
int nr_scanned; unsigned long reap = 0; |
09cc9fc7a
|
682 |
spin_lock(&sb->s_inode_lru_lock); |
b0d40c92a
|
683 |
for (nr_scanned = nr_to_scan; nr_scanned >= 0; nr_scanned--) { |
1da177e4c
|
684 |
struct inode *inode; |
98b745c64
|
685 |
if (list_empty(&sb->s_inode_lru)) |
1da177e4c
|
686 |
break; |
98b745c64
|
687 |
inode = list_entry(sb->s_inode_lru.prev, struct inode, i_lru); |
1da177e4c
|
688 |
|
9e38d86ff
|
689 |
/* |
09cc9fc7a
|
690 |
* we are inverting the sb->s_inode_lru_lock/inode->i_lock here, |
02afc410f
|
691 692 693 694 |
* so use a trylock. If we fail to get the lock, just move the * inode to the back of the list so we don't spin on it. */ if (!spin_trylock(&inode->i_lock)) { |
62a3ddef6
|
695 |
list_move_tail(&inode->i_lru, &sb->s_inode_lru); |
02afc410f
|
696 697 698 699 |
continue; } /* |
9e38d86ff
|
700 701 702 703 704 |
* Referenced or dirty inodes are still in use. Give them * another pass through the LRU as we canot reclaim them now. */ if (atomic_read(&inode->i_count) || (inode->i_state & ~I_REFERENCED)) { |
7ccf19a80
|
705 |
list_del_init(&inode->i_lru); |
f283c86af
|
706 |
spin_unlock(&inode->i_lock); |
98b745c64
|
707 |
sb->s_nr_inodes_unused--; |
fcb94f72d
|
708 |
this_cpu_dec(nr_unused); |
9e38d86ff
|
709 710 711 712 713 |
continue; } /* recently referenced inodes get one more pass */ if (inode->i_state & I_REFERENCED) { |
9e38d86ff
|
714 |
inode->i_state &= ~I_REFERENCED; |
98b745c64
|
715 |
list_move(&inode->i_lru, &sb->s_inode_lru); |
f283c86af
|
716 |
spin_unlock(&inode->i_lock); |
1da177e4c
|
717 718 719 720 |
continue; } if (inode_has_buffers(inode) || inode->i_data.nrpages) { __iget(inode); |
250df6ed2
|
721 |
spin_unlock(&inode->i_lock); |
09cc9fc7a
|
722 |
spin_unlock(&sb->s_inode_lru_lock); |
1da177e4c
|
723 |
if (remove_inode_buffers(inode)) |
fc0ecff69
|
724 725 |
reap += invalidate_mapping_pages(&inode->i_data, 0, -1); |
1da177e4c
|
726 |
iput(inode); |
09cc9fc7a
|
727 |
spin_lock(&sb->s_inode_lru_lock); |
1da177e4c
|
728 |
|
98b745c64
|
729 |
if (inode != list_entry(sb->s_inode_lru.next, |
7ccf19a80
|
730 |
struct inode, i_lru)) |
1da177e4c
|
731 |
continue; /* wrong inode or list_empty */ |
02afc410f
|
732 733 734 |
/* avoid lock inversions with trylock */ if (!spin_trylock(&inode->i_lock)) continue; |
250df6ed2
|
735 736 |
if (!can_unuse(inode)) { spin_unlock(&inode->i_lock); |
1da177e4c
|
737 |
continue; |
250df6ed2
|
738 |
} |
1da177e4c
|
739 |
} |
7ef0d7377
|
740 |
WARN_ON(inode->i_state & I_NEW); |
1da177e4c
|
741 |
inode->i_state |= I_FREEING; |
250df6ed2
|
742 |
spin_unlock(&inode->i_lock); |
7ccf19a80
|
743 |
|
7ccf19a80
|
744 |
list_move(&inode->i_lru, &freeable); |
98b745c64
|
745 |
sb->s_nr_inodes_unused--; |
fcb94f72d
|
746 |
this_cpu_dec(nr_unused); |
1da177e4c
|
747 |
} |
f8891e5e1
|
748 749 750 751 |
if (current_is_kswapd()) __count_vm_events(KSWAPD_INODESTEAL, reap); else __count_vm_events(PGINODESTEAL, reap); |
09cc9fc7a
|
752 |
spin_unlock(&sb->s_inode_lru_lock); |
5f8aefd44
|
753 754 |
if (current->reclaim_state) current->reclaim_state->reclaimed_slab += reap; |
1da177e4c
|
755 756 |
dispose_list(&freeable); |
1da177e4c
|
757 |
} |
1da177e4c
|
758 759 760 |
static void __wait_on_freeing_inode(struct inode *inode); /* * Called with the inode lock held. |
1da177e4c
|
761 |
*/ |
6b3304b53
|
762 763 764 765 |
static struct inode *find_inode(struct super_block *sb, struct hlist_head *head, int (*test)(struct inode *, void *), void *data) |
1da177e4c
|
766 767 |
{ struct hlist_node *node; |
6b3304b53
|
768 |
struct inode *inode = NULL; |
1da177e4c
|
769 770 |
repeat: |
c5c8be3ce
|
771 |
hlist_for_each_entry(inode, node, head, i_hash) { |
67a23c494
|
772 773 774 |
spin_lock(&inode->i_lock); if (inode->i_sb != sb) { spin_unlock(&inode->i_lock); |
1da177e4c
|
775 |
continue; |
67a23c494
|
776 777 778 |
} if (!test(inode, data)) { spin_unlock(&inode->i_lock); |
1da177e4c
|
779 |
continue; |
67a23c494
|
780 |
} |
a4ffdde6e
|
781 |
if (inode->i_state & (I_FREEING|I_WILL_FREE)) { |
1da177e4c
|
782 783 784 |
__wait_on_freeing_inode(inode); goto repeat; } |
f7899bd54
|
785 |
__iget(inode); |
250df6ed2
|
786 |
spin_unlock(&inode->i_lock); |
f7899bd54
|
787 |
return inode; |
1da177e4c
|
788 |
} |
f7899bd54
|
789 |
return NULL; |
1da177e4c
|
790 791 792 793 794 795 |
} /* * find_inode_fast is the fast path version of find_inode, see the comment at * iget_locked for details. */ |
6b3304b53
|
796 797 |
static struct inode *find_inode_fast(struct super_block *sb, struct hlist_head *head, unsigned long ino) |
1da177e4c
|
798 799 |
{ struct hlist_node *node; |
6b3304b53
|
800 |
struct inode *inode = NULL; |
1da177e4c
|
801 802 |
repeat: |
c5c8be3ce
|
803 |
hlist_for_each_entry(inode, node, head, i_hash) { |
67a23c494
|
804 805 806 |
spin_lock(&inode->i_lock); if (inode->i_ino != ino) { spin_unlock(&inode->i_lock); |
1da177e4c
|
807 |
continue; |
67a23c494
|
808 809 810 |
} if (inode->i_sb != sb) { spin_unlock(&inode->i_lock); |
1da177e4c
|
811 |
continue; |
67a23c494
|
812 |
} |
a4ffdde6e
|
813 |
if (inode->i_state & (I_FREEING|I_WILL_FREE)) { |
1da177e4c
|
814 815 816 |
__wait_on_freeing_inode(inode); goto repeat; } |
f7899bd54
|
817 |
__iget(inode); |
250df6ed2
|
818 |
spin_unlock(&inode->i_lock); |
f7899bd54
|
819 |
return inode; |
1da177e4c
|
820 |
} |
f7899bd54
|
821 |
return NULL; |
8290c35f8
|
822 |
} |
f991bd2e1
|
823 824 825 826 |
/* * Each cpu owns a range of LAST_INO_BATCH numbers. * 'shared_last_ino' is dirtied only once out of LAST_INO_BATCH allocations, * to renew the exhausted range. |
8290c35f8
|
827 |
* |
f991bd2e1
|
828 829 830 831 832 833 834 835 836 |
* This does not significantly increase overflow rate because every CPU can * consume at most LAST_INO_BATCH-1 unused inode numbers. So there is * NR_CPUS*(LAST_INO_BATCH-1) wastage. At 4096 and 1024, this is ~0.1% of the * 2^32 range, and is a worst-case. Even a 50% wastage would only increase * overflow rate by 2x, which does not seem too significant. * * On a 32bit, non LFS stat() call, glibc will generate an EOVERFLOW * error if st_ino won't fit in target struct field. Use 32bit counter * here to attempt to avoid that. |
8290c35f8
|
837 |
*/ |
f991bd2e1
|
838 839 |
#define LAST_INO_BATCH 1024 static DEFINE_PER_CPU(unsigned int, last_ino); |
85fe4025c
|
840 |
unsigned int get_next_ino(void) |
8290c35f8
|
841 |
{ |
f991bd2e1
|
842 843 |
unsigned int *p = &get_cpu_var(last_ino); unsigned int res = *p; |
8290c35f8
|
844 |
|
f991bd2e1
|
845 846 847 848 849 850 851 852 853 854 855 856 |
#ifdef CONFIG_SMP if (unlikely((res & (LAST_INO_BATCH-1)) == 0)) { static atomic_t shared_last_ino; int next = atomic_add_return(LAST_INO_BATCH, &shared_last_ino); res = next - LAST_INO_BATCH; } #endif *p = ++res; put_cpu_var(last_ino); return res; |
8290c35f8
|
857 |
} |
85fe4025c
|
858 |
EXPORT_SYMBOL(get_next_ino); |
8290c35f8
|
859 |
|
1da177e4c
|
860 |
/** |
a209dfc7b
|
861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 |
* new_inode_pseudo - obtain an inode * @sb: superblock * * Allocates a new inode for given superblock. * Inode wont be chained in superblock s_inodes list * This means : * - fs can't be unmount * - quotas, fsnotify, writeback can't work */ struct inode *new_inode_pseudo(struct super_block *sb) { struct inode *inode = alloc_inode(sb); if (inode) { spin_lock(&inode->i_lock); inode->i_state = 0; spin_unlock(&inode->i_lock); INIT_LIST_HEAD(&inode->i_sb_list); } return inode; } /** |
1da177e4c
|
884 885 886 |
* new_inode - obtain an inode * @sb: superblock * |
769848c03
|
887 |
* Allocates a new inode for given superblock. The default gfp_mask |
3c1d43787
|
888 |
* for allocations related to inode->i_mapping is GFP_HIGHUSER_MOVABLE. |
769848c03
|
889 890 891 892 893 |
* If HIGHMEM pages are unsuitable or it is known that pages allocated * for the page cache are not reclaimable or migratable, * mapping_set_gfp_mask() must be called with suitable flags on the * newly created inode's mapping * |
1da177e4c
|
894 895 896 |
*/ struct inode *new_inode(struct super_block *sb) { |
6b3304b53
|
897 |
struct inode *inode; |
1da177e4c
|
898 |
|
55fa6091d
|
899 |
spin_lock_prefetch(&inode_sb_list_lock); |
6b3304b53
|
900 |
|
a209dfc7b
|
901 902 |
inode = new_inode_pseudo(sb); if (inode) |
55fa6091d
|
903 |
inode_sb_list_add(inode); |
1da177e4c
|
904 905 |
return inode; } |
1da177e4c
|
906 |
EXPORT_SYMBOL(new_inode); |
14358e6dd
|
907 |
#ifdef CONFIG_DEBUG_LOCK_ALLOC |
e096d0c7e
|
908 909 |
void lockdep_annotate_inode_mutex_key(struct inode *inode) { |
a3314a0ed
|
910 |
if (S_ISDIR(inode->i_mode)) { |
1e89a5e15
|
911 |
struct file_system_type *type = inode->i_sb->s_type; |
9a7aa12f3
|
912 |
/* Set new key only if filesystem hasn't already changed it */ |
978d6d8c4
|
913 |
if (lockdep_match_class(&inode->i_mutex, &type->i_mutex_key)) { |
9a7aa12f3
|
914 915 916 917 918 919 920 921 |
/* * ensure nobody is actually holding i_mutex */ mutex_destroy(&inode->i_mutex); mutex_init(&inode->i_mutex); lockdep_set_class(&inode->i_mutex, &type->i_mutex_dir_key); } |
1e89a5e15
|
922 |
} |
e096d0c7e
|
923 924 |
} EXPORT_SYMBOL(lockdep_annotate_inode_mutex_key); |
14358e6dd
|
925 |
#endif |
e096d0c7e
|
926 927 928 929 930 931 932 933 934 935 936 |
/** * unlock_new_inode - clear the I_NEW state and wake up any waiters * @inode: new inode to unlock * * Called when the inode is fully initialised to clear the new state of the * inode and wake up anyone waiting for the inode to finish initialisation. */ void unlock_new_inode(struct inode *inode) { lockdep_annotate_inode_mutex_key(inode); |
250df6ed2
|
937 |
spin_lock(&inode->i_lock); |
eaff8079d
|
938 939 |
WARN_ON(!(inode->i_state & I_NEW)); inode->i_state &= ~I_NEW; |
310fa7a36
|
940 |
smp_mb(); |
250df6ed2
|
941 942 |
wake_up_bit(&inode->i_state, __I_NEW); spin_unlock(&inode->i_lock); |
1da177e4c
|
943 |
} |
1da177e4c
|
944 |
EXPORT_SYMBOL(unlock_new_inode); |
0b2d0724e
|
945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 |
/** * iget5_locked - obtain an inode from a mounted file system * @sb: super block of file system * @hashval: hash value (usually inode number) to get * @test: callback used for comparisons between inodes * @set: callback used to initialize a new struct inode * @data: opaque data pointer to pass to @test and @set * * Search for the inode specified by @hashval and @data in the inode cache, * and if present it is return it with an increased reference count. This is * a generalized version of iget_locked() for file systems where the inode * number is not sufficient for unique identification of an inode. * * If the inode is not in cache, allocate a new inode and return it locked, * hashed, and with the I_NEW flag set. The file system gets to fill it in * before unlocking it via unlock_new_inode(). |
1da177e4c
|
961 |
* |
0b2d0724e
|
962 963 |
* Note both @test and @set are called with the inode_hash_lock held, so can't * sleep. |
1da177e4c
|
964 |
*/ |
0b2d0724e
|
965 966 967 |
struct inode *iget5_locked(struct super_block *sb, unsigned long hashval, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *data) |
1da177e4c
|
968 |
{ |
0b2d0724e
|
969 |
struct hlist_head *head = inode_hashtable + hash(sb, hashval); |
6b3304b53
|
970 |
struct inode *inode; |
1da177e4c
|
971 |
|
0b2d0724e
|
972 973 974 975 976 977 978 979 |
spin_lock(&inode_hash_lock); inode = find_inode(sb, head, test, data); spin_unlock(&inode_hash_lock); if (inode) { wait_on_inode(inode); return inode; } |
1da177e4c
|
980 981 |
inode = alloc_inode(sb); if (inode) { |
6b3304b53
|
982 |
struct inode *old; |
1da177e4c
|
983 |
|
67a23c494
|
984 |
spin_lock(&inode_hash_lock); |
1da177e4c
|
985 986 987 988 989 |
/* We released the lock, so.. */ old = find_inode(sb, head, test, data); if (!old) { if (set(inode, data)) goto set_failed; |
250df6ed2
|
990 991 |
spin_lock(&inode->i_lock); inode->i_state = I_NEW; |
646ec4615
|
992 |
hlist_add_head(&inode->i_hash, head); |
250df6ed2
|
993 |
spin_unlock(&inode->i_lock); |
55fa6091d
|
994 |
inode_sb_list_add(inode); |
67a23c494
|
995 |
spin_unlock(&inode_hash_lock); |
1da177e4c
|
996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 |
/* Return the locked inode with I_NEW set, the * caller is responsible for filling in the contents */ return inode; } /* * Uhhuh, somebody else created the same inode under * us. Use the old inode instead of the one we just * allocated. */ |
67a23c494
|
1008 |
spin_unlock(&inode_hash_lock); |
1da177e4c
|
1009 1010 1011 1012 1013 1014 1015 |
destroy_inode(inode); inode = old; wait_on_inode(inode); } return inode; set_failed: |
67a23c494
|
1016 |
spin_unlock(&inode_hash_lock); |
1da177e4c
|
1017 1018 1019 |
destroy_inode(inode); return NULL; } |
0b2d0724e
|
1020 |
EXPORT_SYMBOL(iget5_locked); |
1da177e4c
|
1021 |
|
0b2d0724e
|
1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 |
/** * iget_locked - obtain an inode from a mounted file system * @sb: super block of file system * @ino: inode number to get * * Search for the inode specified by @ino in the inode cache and if present * return it with an increased reference count. This is for file systems * where the inode number is sufficient for unique identification of an inode. * * If the inode is not in cache, allocate a new inode and return it locked, * hashed, and with the I_NEW flag set. The file system gets to fill it in * before unlocking it via unlock_new_inode(). |
1da177e4c
|
1034 |
*/ |
0b2d0724e
|
1035 |
struct inode *iget_locked(struct super_block *sb, unsigned long ino) |
1da177e4c
|
1036 |
{ |
0b2d0724e
|
1037 |
struct hlist_head *head = inode_hashtable + hash(sb, ino); |
6b3304b53
|
1038 |
struct inode *inode; |
1da177e4c
|
1039 |
|
0b2d0724e
|
1040 1041 1042 1043 1044 1045 1046 |
spin_lock(&inode_hash_lock); inode = find_inode_fast(sb, head, ino); spin_unlock(&inode_hash_lock); if (inode) { wait_on_inode(inode); return inode; } |
1da177e4c
|
1047 1048 |
inode = alloc_inode(sb); if (inode) { |
6b3304b53
|
1049 |
struct inode *old; |
1da177e4c
|
1050 |
|
67a23c494
|
1051 |
spin_lock(&inode_hash_lock); |
1da177e4c
|
1052 1053 1054 1055 |
/* We released the lock, so.. */ old = find_inode_fast(sb, head, ino); if (!old) { inode->i_ino = ino; |
250df6ed2
|
1056 1057 |
spin_lock(&inode->i_lock); inode->i_state = I_NEW; |
646ec4615
|
1058 |
hlist_add_head(&inode->i_hash, head); |
250df6ed2
|
1059 |
spin_unlock(&inode->i_lock); |
55fa6091d
|
1060 |
inode_sb_list_add(inode); |
67a23c494
|
1061 |
spin_unlock(&inode_hash_lock); |
1da177e4c
|
1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 |
/* Return the locked inode with I_NEW set, the * caller is responsible for filling in the contents */ return inode; } /* * Uhhuh, somebody else created the same inode under * us. Use the old inode instead of the one we just * allocated. */ |
67a23c494
|
1074 |
spin_unlock(&inode_hash_lock); |
1da177e4c
|
1075 1076 1077 1078 1079 1080 |
destroy_inode(inode); inode = old; wait_on_inode(inode); } return inode; } |
0b2d0724e
|
1081 |
EXPORT_SYMBOL(iget_locked); |
1da177e4c
|
1082 |
|
ad5e195ac
|
1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 |
/* * search the inode cache for a matching inode number. * If we find one, then the inode number we are trying to * allocate is not unique and so we should not use it. * * Returns 1 if the inode number is unique, 0 if it is not. */ static int test_inode_iunique(struct super_block *sb, unsigned long ino) { struct hlist_head *b = inode_hashtable + hash(sb, ino); struct hlist_node *node; struct inode *inode; |
67a23c494
|
1095 |
spin_lock(&inode_hash_lock); |
ad5e195ac
|
1096 |
hlist_for_each_entry(inode, node, b, i_hash) { |
67a23c494
|
1097 1098 |
if (inode->i_ino == ino && inode->i_sb == sb) { spin_unlock(&inode_hash_lock); |
ad5e195ac
|
1099 |
return 0; |
67a23c494
|
1100 |
} |
ad5e195ac
|
1101 |
} |
67a23c494
|
1102 |
spin_unlock(&inode_hash_lock); |
ad5e195ac
|
1103 1104 1105 |
return 1; } |
1da177e4c
|
1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 |
/** * iunique - get a unique inode number * @sb: superblock * @max_reserved: highest reserved inode number * * Obtain an inode number that is unique on the system for a given * superblock. This is used by file systems that have no natural * permanent inode numbering system. An inode number is returned that * is higher than the reserved limit but unique. * * BUGS: * With a large number of inodes live on the file system this function * currently becomes quite slow. */ ino_t iunique(struct super_block *sb, ino_t max_reserved) { |
866b04fcc
|
1122 1123 1124 1125 1126 |
/* * On a 32bit, non LFS stat() call, glibc will generate an EOVERFLOW * error if st_ino won't fit in target struct field. Use 32bit counter * here to attempt to avoid that. */ |
ad5e195ac
|
1127 |
static DEFINE_SPINLOCK(iunique_lock); |
866b04fcc
|
1128 |
static unsigned int counter; |
1da177e4c
|
1129 |
ino_t res; |
3361c7beb
|
1130 |
|
ad5e195ac
|
1131 |
spin_lock(&iunique_lock); |
3361c7beb
|
1132 1133 1134 |
do { if (counter <= max_reserved) counter = max_reserved + 1; |
1da177e4c
|
1135 |
res = counter++; |
ad5e195ac
|
1136 1137 |
} while (!test_inode_iunique(sb, res)); spin_unlock(&iunique_lock); |
1da177e4c
|
1138 |
|
3361c7beb
|
1139 1140 |
return res; } |
1da177e4c
|
1141 1142 1143 1144 |
EXPORT_SYMBOL(iunique); struct inode *igrab(struct inode *inode) { |
250df6ed2
|
1145 1146 |
spin_lock(&inode->i_lock); if (!(inode->i_state & (I_FREEING|I_WILL_FREE))) { |
1da177e4c
|
1147 |
__iget(inode); |
250df6ed2
|
1148 1149 1150 |
spin_unlock(&inode->i_lock); } else { spin_unlock(&inode->i_lock); |
1da177e4c
|
1151 1152 1153 1154 1155 1156 |
/* * Handle the case where s_op->clear_inode is not been * called yet, and somebody is calling igrab * while the inode is getting freed. */ inode = NULL; |
250df6ed2
|
1157 |
} |
1da177e4c
|
1158 1159 |
return inode; } |
1da177e4c
|
1160 1161 1162 |
EXPORT_SYMBOL(igrab); /** |
0b2d0724e
|
1163 |
* ilookup5_nowait - search for an inode in the inode cache |
1da177e4c
|
1164 |
* @sb: super block of file system to search |
0b2d0724e
|
1165 |
* @hashval: hash value (usually inode number) to search for |
1da177e4c
|
1166 1167 |
* @test: callback used for comparisons between inodes * @data: opaque data pointer to pass to @test |
1da177e4c
|
1168 |
* |
0b2d0724e
|
1169 |
* Search for the inode specified by @hashval and @data in the inode cache. |
1da177e4c
|
1170 1171 1172 |
* If the inode is in the cache, the inode is returned with an incremented * reference count. * |
0b2d0724e
|
1173 1174 |
* Note: I_NEW is not waited upon so you have to be very careful what you do * with the returned inode. You probably should be using ilookup5() instead. |
1da177e4c
|
1175 |
* |
b6d0ad686
|
1176 |
* Note2: @test is called with the inode_hash_lock held, so can't sleep. |
1da177e4c
|
1177 |
*/ |
0b2d0724e
|
1178 1179 |
struct inode *ilookup5_nowait(struct super_block *sb, unsigned long hashval, int (*test)(struct inode *, void *), void *data) |
1da177e4c
|
1180 |
{ |
0b2d0724e
|
1181 |
struct hlist_head *head = inode_hashtable + hash(sb, hashval); |
1da177e4c
|
1182 |
struct inode *inode; |
67a23c494
|
1183 |
spin_lock(&inode_hash_lock); |
1da177e4c
|
1184 |
inode = find_inode(sb, head, test, data); |
67a23c494
|
1185 |
spin_unlock(&inode_hash_lock); |
88bd5121d
|
1186 |
|
0b2d0724e
|
1187 |
return inode; |
88bd5121d
|
1188 |
} |
88bd5121d
|
1189 1190 1191 1192 1193 1194 1195 1196 1197 |
EXPORT_SYMBOL(ilookup5_nowait); /** * ilookup5 - search for an inode in the inode cache * @sb: super block of file system to search * @hashval: hash value (usually inode number) to search for * @test: callback used for comparisons between inodes * @data: opaque data pointer to pass to @test * |
0b2d0724e
|
1198 1199 1200 |
* Search for the inode specified by @hashval and @data in the inode cache, * and if the inode is in the cache, return the inode with an incremented * reference count. Waits on I_NEW before returning the inode. |
88bd5121d
|
1201 |
* returned with an incremented reference count. |
1da177e4c
|
1202 |
* |
0b2d0724e
|
1203 1204 |
* This is a generalized version of ilookup() for file systems where the * inode number is not sufficient for unique identification of an inode. |
1da177e4c
|
1205 |
* |
0b2d0724e
|
1206 |
* Note: @test is called with the inode_hash_lock held, so can't sleep. |
1da177e4c
|
1207 1208 1209 1210 |
*/ struct inode *ilookup5(struct super_block *sb, unsigned long hashval, int (*test)(struct inode *, void *), void *data) { |
0b2d0724e
|
1211 |
struct inode *inode = ilookup5_nowait(sb, hashval, test, data); |
1da177e4c
|
1212 |
|
0b2d0724e
|
1213 1214 1215 |
if (inode) wait_on_inode(inode); return inode; |
1da177e4c
|
1216 |
} |
1da177e4c
|
1217 1218 1219 1220 1221 1222 1223 |
EXPORT_SYMBOL(ilookup5); /** * ilookup - search for an inode in the inode cache * @sb: super block of file system to search * @ino: inode number to search for * |
0b2d0724e
|
1224 1225 |
* Search for the inode @ino in the inode cache, and if the inode is in the * cache, the inode is returned with an incremented reference count. |
1da177e4c
|
1226 1227 1228 1229 |
*/ struct inode *ilookup(struct super_block *sb, unsigned long ino) { struct hlist_head *head = inode_hashtable + hash(sb, ino); |
1da177e4c
|
1230 |
struct inode *inode; |
0b2d0724e
|
1231 1232 1233 |
spin_lock(&inode_hash_lock); inode = find_inode_fast(sb, head, ino); spin_unlock(&inode_hash_lock); |
1da177e4c
|
1234 |
|
1da177e4c
|
1235 |
if (inode) |
0b2d0724e
|
1236 1237 |
wait_on_inode(inode); return inode; |
1da177e4c
|
1238 |
} |
0b2d0724e
|
1239 |
EXPORT_SYMBOL(ilookup); |
1da177e4c
|
1240 |
|
261bca86e
|
1241 1242 1243 1244 1245 |
int insert_inode_locked(struct inode *inode) { struct super_block *sb = inode->i_sb; ino_t ino = inode->i_ino; struct hlist_head *head = inode_hashtable + hash(sb, ino); |
261bca86e
|
1246 |
|
261bca86e
|
1247 |
while (1) { |
72a43d63c
|
1248 1249 |
struct hlist_node *node; struct inode *old = NULL; |
67a23c494
|
1250 |
spin_lock(&inode_hash_lock); |
72a43d63c
|
1251 1252 1253 1254 1255 |
hlist_for_each_entry(old, node, head, i_hash) { if (old->i_ino != ino) continue; if (old->i_sb != sb) continue; |
250df6ed2
|
1256 1257 1258 |
spin_lock(&old->i_lock); if (old->i_state & (I_FREEING|I_WILL_FREE)) { spin_unlock(&old->i_lock); |
72a43d63c
|
1259 |
continue; |
250df6ed2
|
1260 |
} |
72a43d63c
|
1261 1262 1263 |
break; } if (likely(!node)) { |
250df6ed2
|
1264 1265 |
spin_lock(&inode->i_lock); inode->i_state |= I_NEW; |
261bca86e
|
1266 |
hlist_add_head(&inode->i_hash, head); |
250df6ed2
|
1267 |
spin_unlock(&inode->i_lock); |
67a23c494
|
1268 |
spin_unlock(&inode_hash_lock); |
261bca86e
|
1269 1270 1271 |
return 0; } __iget(old); |
250df6ed2
|
1272 |
spin_unlock(&old->i_lock); |
67a23c494
|
1273 |
spin_unlock(&inode_hash_lock); |
261bca86e
|
1274 |
wait_on_inode(old); |
1d3382cbf
|
1275 |
if (unlikely(!inode_unhashed(old))) { |
261bca86e
|
1276 1277 1278 1279 1280 1281 |
iput(old); return -EBUSY; } iput(old); } } |
261bca86e
|
1282 1283 1284 1285 1286 1287 1288 |
EXPORT_SYMBOL(insert_inode_locked); int insert_inode_locked4(struct inode *inode, unsigned long hashval, int (*test)(struct inode *, void *), void *data) { struct super_block *sb = inode->i_sb; struct hlist_head *head = inode_hashtable + hash(sb, hashval); |
261bca86e
|
1289 |
|
261bca86e
|
1290 |
while (1) { |
72a43d63c
|
1291 1292 |
struct hlist_node *node; struct inode *old = NULL; |
67a23c494
|
1293 |
spin_lock(&inode_hash_lock); |
72a43d63c
|
1294 1295 1296 1297 1298 |
hlist_for_each_entry(old, node, head, i_hash) { if (old->i_sb != sb) continue; if (!test(old, data)) continue; |
250df6ed2
|
1299 1300 1301 |
spin_lock(&old->i_lock); if (old->i_state & (I_FREEING|I_WILL_FREE)) { spin_unlock(&old->i_lock); |
72a43d63c
|
1302 |
continue; |
250df6ed2
|
1303 |
} |
72a43d63c
|
1304 1305 1306 |
break; } if (likely(!node)) { |
250df6ed2
|
1307 1308 |
spin_lock(&inode->i_lock); inode->i_state |= I_NEW; |
261bca86e
|
1309 |
hlist_add_head(&inode->i_hash, head); |
250df6ed2
|
1310 |
spin_unlock(&inode->i_lock); |
67a23c494
|
1311 |
spin_unlock(&inode_hash_lock); |
261bca86e
|
1312 1313 1314 |
return 0; } __iget(old); |
250df6ed2
|
1315 |
spin_unlock(&old->i_lock); |
67a23c494
|
1316 |
spin_unlock(&inode_hash_lock); |
261bca86e
|
1317 |
wait_on_inode(old); |
1d3382cbf
|
1318 |
if (unlikely(!inode_unhashed(old))) { |
261bca86e
|
1319 1320 1321 1322 1323 1324 |
iput(old); return -EBUSY; } iput(old); } } |
261bca86e
|
1325 |
EXPORT_SYMBOL(insert_inode_locked4); |
1da177e4c
|
1326 |
|
45321ac54
|
1327 1328 1329 1330 1331 |
int generic_delete_inode(struct inode *inode) { return 1; } EXPORT_SYMBOL(generic_delete_inode); |
1da177e4c
|
1332 |
/* |
45321ac54
|
1333 1334 |
* Called when we're dropping the last reference * to an inode. |
22fe40421
|
1335 |
* |
45321ac54
|
1336 1337 1338 1339 1340 |
* Call the FS "drop_inode()" function, defaulting to * the legacy UNIX filesystem behaviour. If it tells * us to evict inode, do so. Otherwise, retain inode * in cache if fs is alive, sync and evict if fs is * shutting down. |
22fe40421
|
1341 |
*/ |
45321ac54
|
1342 |
static void iput_final(struct inode *inode) |
1da177e4c
|
1343 1344 |
{ struct super_block *sb = inode->i_sb; |
45321ac54
|
1345 1346 |
const struct super_operations *op = inode->i_sb->s_op; int drop; |
250df6ed2
|
1347 |
WARN_ON(inode->i_state & I_NEW); |
e7f590970
|
1348 |
if (op->drop_inode) |
45321ac54
|
1349 1350 1351 |
drop = op->drop_inode(inode); else drop = generic_drop_inode(inode); |
1da177e4c
|
1352 |
|
b2b2af8e6
|
1353 1354 |
if (!drop && (sb->s_flags & MS_ACTIVE)) { inode->i_state |= I_REFERENCED; |
4eff96dd5
|
1355 |
inode_add_lru(inode); |
b2b2af8e6
|
1356 |
spin_unlock(&inode->i_lock); |
b2b2af8e6
|
1357 1358 |
return; } |
45321ac54
|
1359 |
if (!drop) { |
991114c6f
|
1360 |
inode->i_state |= I_WILL_FREE; |
250df6ed2
|
1361 |
spin_unlock(&inode->i_lock); |
1da177e4c
|
1362 |
write_inode_now(inode, 1); |
250df6ed2
|
1363 |
spin_lock(&inode->i_lock); |
7ef0d7377
|
1364 |
WARN_ON(inode->i_state & I_NEW); |
991114c6f
|
1365 |
inode->i_state &= ~I_WILL_FREE; |
1da177e4c
|
1366 |
} |
7ccf19a80
|
1367 |
|
991114c6f
|
1368 |
inode->i_state |= I_FREEING; |
c4ae0c654
|
1369 1370 |
if (!list_empty(&inode->i_lru)) inode_lru_list_del(inode); |
b2b2af8e6
|
1371 |
spin_unlock(&inode->i_lock); |
b2b2af8e6
|
1372 |
|
644da5960
|
1373 |
evict(inode); |
1da177e4c
|
1374 |
} |
1da177e4c
|
1375 |
/** |
6b3304b53
|
1376 |
* iput - put an inode |
1da177e4c
|
1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 |
* @inode: inode to put * * Puts an inode, dropping its usage count. If the inode use count hits * zero, the inode is then freed and may also be destroyed. * * Consequently, iput() can sleep. */ void iput(struct inode *inode) { if (inode) { |
a4ffdde6e
|
1387 |
BUG_ON(inode->i_state & I_CLEAR); |
1da177e4c
|
1388 |
|
f283c86af
|
1389 |
if (atomic_dec_and_lock(&inode->i_count, &inode->i_lock)) |
1da177e4c
|
1390 1391 1392 |
iput_final(inode); } } |
1da177e4c
|
1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 |
EXPORT_SYMBOL(iput); /** * bmap - find a block number in a file * @inode: inode of file * @block: block to find * * Returns the block number on the device holding the inode that * is the disk block number for the block of the file requested. * That is, asked for block 4 of inode 1 the function will return the |
6b3304b53
|
1403 |
* disk block relative to the disk start that holds that block of the |
1da177e4c
|
1404 1405 |
* file. */ |
6b3304b53
|
1406 |
sector_t bmap(struct inode *inode, sector_t block) |
1da177e4c
|
1407 1408 1409 1410 1411 1412 |
{ sector_t res = 0; if (inode->i_mapping->a_ops->bmap) res = inode->i_mapping->a_ops->bmap(inode->i_mapping, block); return res; } |
1da177e4c
|
1413 |
EXPORT_SYMBOL(bmap); |
11ff6f05f
|
1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 |
/* * With relative atime, only update atime if the previous atime is * earlier than either the ctime or mtime or if at least a day has * passed since the last atime update. */ static int relatime_need_update(struct vfsmount *mnt, struct inode *inode, struct timespec now) { if (!(mnt->mnt_flags & MNT_RELATIME)) return 1; /* * Is mtime younger than atime? If yes, update atime: */ if (timespec_compare(&inode->i_mtime, &inode->i_atime) >= 0) return 1; /* * Is ctime younger than atime? If yes, update atime: */ if (timespec_compare(&inode->i_ctime, &inode->i_atime) >= 0) return 1; /* * Is the previous atime value older than a day? If yes, * update atime: */ if ((long)(now.tv_sec - inode->i_atime.tv_sec) >= 24*60*60) return 1; /* * Good, we can skip the atime update: */ return 0; } |
c3b2da314
|
1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 |
/* * This does the actual work of updating an inodes time or version. Must have * had called mnt_want_write() before calling this. */ static int update_time(struct inode *inode, struct timespec *time, int flags) { if (inode->i_op->update_time) return inode->i_op->update_time(inode, time, flags); if (flags & S_ATIME) inode->i_atime = *time; if (flags & S_VERSION) inode_inc_iversion(inode); if (flags & S_CTIME) inode->i_ctime = *time; if (flags & S_MTIME) inode->i_mtime = *time; mark_inode_dirty_sync(inode); return 0; } |
1da177e4c
|
1467 |
/** |
869243a0f
|
1468 |
* touch_atime - update the access time |
185553b22
|
1469 |
* @path: the &struct path to update |
1da177e4c
|
1470 1471 1472 1473 1474 |
* * Update the accessed time on an inode and mark it for writeback. * This function automatically handles read only file systems and media, * as well as the "noatime" flag and inode specific "noatime" markers. */ |
68ac1234f
|
1475 |
void touch_atime(struct path *path) |
1da177e4c
|
1476 |
{ |
68ac1234f
|
1477 1478 |
struct vfsmount *mnt = path->mnt; struct inode *inode = path->dentry->d_inode; |
1da177e4c
|
1479 |
struct timespec now; |
cdb70f3f7
|
1480 |
if (inode->i_flags & S_NOATIME) |
b12536c27
|
1481 |
return; |
37756ced1
|
1482 |
if (IS_NOATIME(inode)) |
b12536c27
|
1483 |
return; |
b22761384
|
1484 |
if ((inode->i_sb->s_flags & MS_NODIRATIME) && S_ISDIR(inode->i_mode)) |
b12536c27
|
1485 |
return; |
47ae32d6a
|
1486 |
|
cdb70f3f7
|
1487 |
if (mnt->mnt_flags & MNT_NOATIME) |
b12536c27
|
1488 |
return; |
cdb70f3f7
|
1489 |
if ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)) |
b12536c27
|
1490 |
return; |
1da177e4c
|
1491 1492 |
now = current_fs_time(inode->i_sb); |
11ff6f05f
|
1493 1494 |
if (!relatime_need_update(mnt, inode, now)) |
b12536c27
|
1495 |
return; |
11ff6f05f
|
1496 |
|
47ae32d6a
|
1497 |
if (timespec_equal(&inode->i_atime, &now)) |
b12536c27
|
1498 |
return; |
5d37e9e6d
|
1499 |
if (!sb_start_write_trylock(inode->i_sb)) |
b12536c27
|
1500 |
return; |
47ae32d6a
|
1501 |
|
5d37e9e6d
|
1502 1503 |
if (__mnt_want_write(mnt)) goto skip_update; |
c3b2da314
|
1504 1505 1506 1507 1508 1509 |
/* * File systems can error out when updating inodes if they need to * allocate new space to modify an inode (such is the case for * Btrfs), but since we touch atime while walking down the path we * really don't care if we failed to update the atime of the file, * so just ignore the return value. |
2bc556528
|
1510 1511 |
* We may also fail on filesystems that have the ability to make parts * of the fs read only, e.g. subvolumes in Btrfs. |
c3b2da314
|
1512 1513 |
*/ update_time(inode, &now, S_ATIME); |
5d37e9e6d
|
1514 1515 1516 |
__mnt_drop_write(mnt); skip_update: sb_end_write(inode->i_sb); |
1da177e4c
|
1517 |
} |
869243a0f
|
1518 |
EXPORT_SYMBOL(touch_atime); |
1da177e4c
|
1519 |
|
3ed37648e
|
1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 |
/* * The logic we want is * * if suid or (sgid and xgrp) * remove privs */ int should_remove_suid(struct dentry *dentry) { umode_t mode = dentry->d_inode->i_mode; int kill = 0; /* suid always must be killed */ if (unlikely(mode & S_ISUID)) kill = ATTR_KILL_SUID; /* * sgid without any exec bits is just a mandatory locking mark; leave * it alone. If some exec bits are set, it's a real sgid; kill it. */ if (unlikely((mode & S_ISGID) && (mode & S_IXGRP))) kill |= ATTR_KILL_SGID; if (unlikely(kill && !capable(CAP_FSETID) && S_ISREG(mode))) return kill; return 0; } EXPORT_SYMBOL(should_remove_suid); static int __remove_suid(struct dentry *dentry, int kill) { struct iattr newattrs; newattrs.ia_valid = ATTR_FORCE | kill; return notify_change(dentry, &newattrs); } int file_remove_suid(struct file *file) { struct dentry *dentry = file->f_path.dentry; struct inode *inode = dentry->d_inode; int killsuid; int killpriv; int error = 0; /* Fast path for nothing security related */ if (IS_NOSEC(inode)) return 0; killsuid = should_remove_suid(dentry); killpriv = security_inode_need_killpriv(dentry); if (killpriv < 0) return killpriv; if (killpriv) error = security_inode_killpriv(dentry); if (!error && killsuid) error = __remove_suid(dentry, killsuid); if (!error && (inode->i_sb->s_flags & MS_NOSEC)) inode->i_flags |= S_NOSEC; return error; } EXPORT_SYMBOL(file_remove_suid); |
1da177e4c
|
1584 |
/** |
870f48179
|
1585 1586 |
* file_update_time - update mtime and ctime time * @file: file accessed |
1da177e4c
|
1587 |
* |
870f48179
|
1588 1589 1590 1591 |
* Update the mtime and ctime members of an inode and mark the inode * for writeback. Note that this function is meant exclusively for * usage in the file write path of filesystems, and filesystems may * choose to explicitly ignore update via this function with the |
2eadfc0ed
|
1592 |
* S_NOCMTIME inode flag, e.g. for network filesystem where these |
c3b2da314
|
1593 1594 |
* timestamps are handled by the server. This can return an error for * file systems who need to allocate space in order to update an inode. |
1da177e4c
|
1595 |
*/ |
c3b2da314
|
1596 |
int file_update_time(struct file *file) |
1da177e4c
|
1597 |
{ |
0f7fc9e4d
|
1598 |
struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4c
|
1599 |
struct timespec now; |
c3b2da314
|
1600 1601 |
int sync_it = 0; int ret; |
1da177e4c
|
1602 |
|
ce06e0b21
|
1603 |
/* First try to exhaust all avenues to not sync */ |
1da177e4c
|
1604 |
if (IS_NOCMTIME(inode)) |
c3b2da314
|
1605 |
return 0; |
20ddee2c7
|
1606 |
|
1da177e4c
|
1607 |
now = current_fs_time(inode->i_sb); |
ce06e0b21
|
1608 1609 |
if (!timespec_equal(&inode->i_mtime, &now)) sync_it = S_MTIME; |
1da177e4c
|
1610 |
|
ce06e0b21
|
1611 1612 |
if (!timespec_equal(&inode->i_ctime, &now)) sync_it |= S_CTIME; |
870f48179
|
1613 |
|
ce06e0b21
|
1614 1615 |
if (IS_I_VERSION(inode)) sync_it |= S_VERSION; |
7a224228e
|
1616 |
|
ce06e0b21
|
1617 |
if (!sync_it) |
c3b2da314
|
1618 |
return 0; |
ce06e0b21
|
1619 1620 |
/* Finally allowed to write? Takes lock. */ |
eb04c2828
|
1621 |
if (__mnt_want_write_file(file)) |
c3b2da314
|
1622 |
return 0; |
ce06e0b21
|
1623 |
|
c3b2da314
|
1624 |
ret = update_time(inode, &now, sync_it); |
eb04c2828
|
1625 |
__mnt_drop_write_file(file); |
c3b2da314
|
1626 1627 |
return ret; |
1da177e4c
|
1628 |
} |
870f48179
|
1629 |
EXPORT_SYMBOL(file_update_time); |
1da177e4c
|
1630 1631 1632 1633 1634 1635 1636 1637 1638 |
int inode_needs_sync(struct inode *inode) { if (IS_SYNC(inode)) return 1; if (S_ISDIR(inode->i_mode) && IS_DIRSYNC(inode)) return 1; return 0; } |
1da177e4c
|
1639 |
EXPORT_SYMBOL(inode_needs_sync); |
1da177e4c
|
1640 1641 1642 1643 1644 |
int inode_wait(void *word) { schedule(); return 0; } |
d44dab8d1
|
1645 |
EXPORT_SYMBOL(inode_wait); |
1da177e4c
|
1646 1647 |
/* |
168a9fd6a
|
1648 1649 1650 1651 1652 1653 |
* If we try to find an inode in the inode hash while it is being * deleted, we have to wait until the filesystem completes its * deletion before reporting that it isn't found. This function waits * until the deletion _might_ have completed. Callers are responsible * to recheck inode state. * |
eaff8079d
|
1654 |
* It doesn't matter if I_NEW is not set initially, a call to |
250df6ed2
|
1655 1656 |
* wake_up_bit(&inode->i_state, __I_NEW) after removing from the hash list * will DTRT. |
1da177e4c
|
1657 1658 1659 1660 |
*/ static void __wait_on_freeing_inode(struct inode *inode) { wait_queue_head_t *wq; |
eaff8079d
|
1661 1662 |
DEFINE_WAIT_BIT(wait, &inode->i_state, __I_NEW); wq = bit_waitqueue(&inode->i_state, __I_NEW); |
1da177e4c
|
1663 |
prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE); |
250df6ed2
|
1664 |
spin_unlock(&inode->i_lock); |
67a23c494
|
1665 |
spin_unlock(&inode_hash_lock); |
1da177e4c
|
1666 1667 |
schedule(); finish_wait(wq, &wait.wait); |
67a23c494
|
1668 |
spin_lock(&inode_hash_lock); |
1da177e4c
|
1669 |
} |
1da177e4c
|
1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 |
static __initdata unsigned long ihash_entries; static int __init set_ihash_entries(char *str) { if (!str) return 0; ihash_entries = simple_strtoul(str, &str, 0); return 1; } __setup("ihash_entries=", set_ihash_entries); /* * Initialize the waitqueues and inode hash table. */ void __init inode_init_early(void) { |
074b85175
|
1685 |
unsigned int loop; |
1da177e4c
|
1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 |
/* If hashes are distributed across NUMA nodes, defer * hash allocation until vmalloc space is available. */ if (hashdist) return; inode_hashtable = alloc_large_system_hash("Inode-cache", sizeof(struct hlist_head), ihash_entries, 14, HASH_EARLY, &i_hash_shift, &i_hash_mask, |
31fe62b95
|
1701 |
0, |
1da177e4c
|
1702 |
0); |
074b85175
|
1703 |
for (loop = 0; loop < (1U << i_hash_shift); loop++) |
1da177e4c
|
1704 1705 |
INIT_HLIST_HEAD(&inode_hashtable[loop]); } |
74bf17cff
|
1706 |
void __init inode_init(void) |
1da177e4c
|
1707 |
{ |
074b85175
|
1708 |
unsigned int loop; |
1da177e4c
|
1709 1710 |
/* inode slab cache */ |
b0196009d
|
1711 1712 1713 1714 1715 |
inode_cachep = kmem_cache_create("inode_cache", sizeof(struct inode), 0, (SLAB_RECLAIM_ACCOUNT|SLAB_PANIC| SLAB_MEM_SPREAD), |
20c2df83d
|
1716 |
init_once); |
1da177e4c
|
1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 |
/* Hash may have been set up in inode_init_early */ if (!hashdist) return; inode_hashtable = alloc_large_system_hash("Inode-cache", sizeof(struct hlist_head), ihash_entries, 14, 0, &i_hash_shift, &i_hash_mask, |
31fe62b95
|
1730 |
0, |
1da177e4c
|
1731 |
0); |
074b85175
|
1732 |
for (loop = 0; loop < (1U << i_hash_shift); loop++) |
1da177e4c
|
1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 |
INIT_HLIST_HEAD(&inode_hashtable[loop]); } void init_special_inode(struct inode *inode, umode_t mode, dev_t rdev) { inode->i_mode = mode; if (S_ISCHR(mode)) { inode->i_fop = &def_chr_fops; inode->i_rdev = rdev; } else if (S_ISBLK(mode)) { inode->i_fop = &def_blk_fops; inode->i_rdev = rdev; } else if (S_ISFIFO(mode)) inode->i_fop = &def_fifo_fops; else if (S_ISSOCK(mode)) inode->i_fop = &bad_sock_fops; else |
af0d9ae81
|
1750 1751 1752 1753 |
printk(KERN_DEBUG "init_special_inode: bogus i_mode (%o) for" " inode %s:%lu ", mode, inode->i_sb->s_id, inode->i_ino); |
1da177e4c
|
1754 1755 |
} EXPORT_SYMBOL(init_special_inode); |
a1bd120d1
|
1756 1757 |
/** |
eaae668d0
|
1758 |
* inode_init_owner - Init uid,gid,mode for new inode according to posix standards |
a1bd120d1
|
1759 1760 1761 1762 1763 |
* @inode: New inode * @dir: Directory inode * @mode: mode of the new inode */ void inode_init_owner(struct inode *inode, const struct inode *dir, |
62bb10917
|
1764 |
umode_t mode) |
a1bd120d1
|
1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 |
{ inode->i_uid = current_fsuid(); if (dir && dir->i_mode & S_ISGID) { inode->i_gid = dir->i_gid; if (S_ISDIR(mode)) mode |= S_ISGID; } else inode->i_gid = current_fsgid(); inode->i_mode = mode; } EXPORT_SYMBOL(inode_init_owner); |
e795b7179
|
1776 |
|
2e1496707
|
1777 1778 1779 1780 1781 1782 |
/** * inode_owner_or_capable - check current task permissions to inode * @inode: inode being checked * * Return true if current either has CAP_FOWNER to the inode, or * owns the file. |
e795b7179
|
1783 |
*/ |
2e1496707
|
1784 |
bool inode_owner_or_capable(const struct inode *inode) |
e795b7179
|
1785 |
{ |
92361636e
|
1786 |
if (uid_eq(current_fsuid(), inode->i_uid)) |
e795b7179
|
1787 |
return true; |
1a48e2ac0
|
1788 |
if (inode_capable(inode, CAP_FOWNER)) |
e795b7179
|
1789 1790 1791 |
return true; return false; } |
2e1496707
|
1792 |
EXPORT_SYMBOL(inode_owner_or_capable); |
1d59d61f6
|
1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 |
/* * Direct i/o helper functions */ static void __inode_dio_wait(struct inode *inode) { wait_queue_head_t *wq = bit_waitqueue(&inode->i_state, __I_DIO_WAKEUP); DEFINE_WAIT_BIT(q, &inode->i_state, __I_DIO_WAKEUP); do { prepare_to_wait(wq, &q.wait, TASK_UNINTERRUPTIBLE); if (atomic_read(&inode->i_dio_count)) schedule(); } while (atomic_read(&inode->i_dio_count)); finish_wait(wq, &q.wait); } /** * inode_dio_wait - wait for outstanding DIO requests to finish * @inode: inode to wait for * * Waits for all pending direct I/O requests to finish so that we can * proceed with a truncate or equivalent operation. * * Must be called under a lock that serializes taking new references * to i_dio_count, usually by inode->i_mutex. */ void inode_dio_wait(struct inode *inode) { if (atomic_read(&inode->i_dio_count)) __inode_dio_wait(inode); } EXPORT_SYMBOL(inode_dio_wait); /* * inode_dio_done - signal finish of a direct I/O requests * @inode: inode the direct I/O happens on * * This is called once we've finished processing a direct I/O request, * and is used to wake up callers waiting for direct I/O to be quiesced. */ void inode_dio_done(struct inode *inode) { if (atomic_dec_and_test(&inode->i_dio_count)) wake_up_bit(&inode->i_state, __I_DIO_WAKEUP); } EXPORT_SYMBOL(inode_dio_done); |