X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Ffs%2Finode.c;h=1be5f9003eb38852f68957fcd287cdd5b820b310;hb=b46c26876daa6e47072270bba7e0635cbcc5002d;hp=6e342cadef81b321f65ccd363ad9499862da9f0c;hpb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;p=kvmfornfv.git diff --git a/kernel/fs/inode.c b/kernel/fs/inode.c index 6e342cade..1be5f9003 100644 --- a/kernel/fs/inode.c +++ b/kernel/fs/inode.c @@ -28,16 +28,16 @@ * inode->i_state, inode->i_hash, __iget() * Inode LRU list locks protect: * inode->i_sb->s_inode_lru, inode->i_lru - * inode_sb_list_lock protects: - * sb->s_inodes, inode->i_sb_list + * inode->i_sb->s_inode_list_lock protects: + * inode->i_sb->s_inodes, inode->i_sb_list * bdi->wb.list_lock protects: - * bdi->wb.b_{dirty,io,more_io,dirty_time}, inode->i_wb_list + * bdi->wb.b_{dirty,io,more_io,dirty_time}, inode->i_io_list * inode_hash_lock protects: * inode_hashtable, inode->i_hash * * Lock ordering: * - * inode_sb_list_lock + * inode->i_sb->s_inode_list_lock * inode->i_lock * Inode LRU list locks * @@ -45,7 +45,7 @@ * inode->i_lock * * inode_hash_lock - * inode_sb_list_lock + * inode->i_sb->s_inode_list_lock * inode->i_lock * * iunique_lock @@ -57,8 +57,6 @@ static unsigned int i_hash_shift __read_mostly; static struct hlist_head *inode_hashtable __read_mostly; static __cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_hash_lock); -__cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_sb_list_lock); - /* * Empty aops. Can be used for the cases where the user does not * define any of the address_space operations. @@ -152,6 +150,7 @@ int inode_init_always(struct super_block *sb, struct inode *inode) inode->i_pipe = NULL; inode->i_bdev = NULL; inode->i_cdev = NULL; + inode->i_link = NULL; inode->i_rdev = 0; inode->dirtied_when = 0; @@ -223,6 +222,7 @@ EXPORT_SYMBOL(free_inode_nonrcu); void __destroy_inode(struct inode *inode) { BUG_ON(inode_has_buffers(inode)); + inode_detach_wb(inode); security_inode_free(inode); fsnotify_inode_delete(inode); locks_free_lock_context(inode->i_flctx); @@ -357,7 +357,7 @@ void inode_init_once(struct inode *inode) memset(inode, 0, sizeof(*inode)); INIT_HLIST_NODE(&inode->i_hash); INIT_LIST_HEAD(&inode->i_devices); - INIT_LIST_HEAD(&inode->i_wb_list); + INIT_LIST_HEAD(&inode->i_io_list); INIT_LIST_HEAD(&inode->i_lru); address_space_init_once(&inode->i_data); i_size_ordered_init(inode); @@ -424,18 +424,18 @@ static void inode_lru_list_del(struct inode *inode) */ void inode_sb_list_add(struct inode *inode) { - spin_lock(&inode_sb_list_lock); + spin_lock(&inode->i_sb->s_inode_list_lock); list_add(&inode->i_sb_list, &inode->i_sb->s_inodes); - spin_unlock(&inode_sb_list_lock); + spin_unlock(&inode->i_sb->s_inode_list_lock); } EXPORT_SYMBOL_GPL(inode_sb_list_add); static inline void inode_sb_list_del(struct inode *inode) { if (!list_empty(&inode->i_sb_list)) { - spin_lock(&inode_sb_list_lock); + spin_lock(&inode->i_sb->s_inode_list_lock); list_del_init(&inode->i_sb_list); - spin_unlock(&inode_sb_list_lock); + spin_unlock(&inode->i_sb->s_inode_list_lock); } } @@ -525,8 +525,8 @@ static void evict(struct inode *inode) BUG_ON(!(inode->i_state & I_FREEING)); BUG_ON(!list_empty(&inode->i_lru)); - if (!list_empty(&inode->i_wb_list)) - inode_wb_list_del(inode); + if (!list_empty(&inode->i_io_list)) + inode_io_list_del(inode); inode_sb_list_del(inode); @@ -575,6 +575,7 @@ static void dispose_list(struct list_head *head) list_del_init(&inode->i_lru); evict(inode); + cond_resched(); } } @@ -592,7 +593,8 @@ void evict_inodes(struct super_block *sb) struct inode *inode, *next; LIST_HEAD(dispose); - spin_lock(&inode_sb_list_lock); +again: + spin_lock(&sb->s_inode_list_lock); list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) { if (atomic_read(&inode->i_count)) continue; @@ -607,8 +609,20 @@ void evict_inodes(struct super_block *sb) inode_lru_list_del(inode); spin_unlock(&inode->i_lock); list_add(&inode->i_lru, &dispose); + + /* + * We can have a ton of inodes to evict at unmount time given + * enough memory, check to see if we need to go to sleep for a + * bit so we don't livelock. + */ + if (need_resched()) { + spin_unlock(&sb->s_inode_list_lock); + cond_resched(); + dispose_list(&dispose); + goto again; + } } - spin_unlock(&inode_sb_list_lock); + spin_unlock(&sb->s_inode_list_lock); dispose_list(&dispose); } @@ -629,7 +643,7 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty) struct inode *inode, *next; LIST_HEAD(dispose); - spin_lock(&inode_sb_list_lock); + spin_lock(&sb->s_inode_list_lock); list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) { spin_lock(&inode->i_lock); if (inode->i_state & (I_NEW | I_FREEING | I_WILL_FREE)) { @@ -652,7 +666,7 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty) spin_unlock(&inode->i_lock); list_add(&inode->i_lru, &dispose); } - spin_unlock(&inode_sb_list_lock); + spin_unlock(&sb->s_inode_list_lock); dispose_list(&dispose); @@ -839,7 +853,11 @@ unsigned int get_next_ino(void) } #endif - *p = ++res; + res++; + /* get_next_ino should not provide a 0 inode number */ + if (unlikely(!res)) + res++; + *p = res; put_cpu_var(last_ino); return res; } @@ -884,7 +902,7 @@ struct inode *new_inode(struct super_block *sb) { struct inode *inode; - spin_lock_prefetch(&inode_sb_list_lock); + spin_lock_prefetch(&sb->s_inode_list_lock); inode = new_inode_pseudo(sb); if (inode) @@ -1579,41 +1597,53 @@ static int update_time(struct inode *inode, struct timespec *time, int flags) /** * touch_atime - update the access time * @path: the &struct path to update + * @inode: inode to update * * 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. */ -void touch_atime(const struct path *path) +bool atime_needs_update(const struct path *path, struct inode *inode) { struct vfsmount *mnt = path->mnt; - struct inode *inode = d_inode(path->dentry); struct timespec now; if (inode->i_flags & S_NOATIME) - return; + return false; if (IS_NOATIME(inode)) - return; + return false; if ((inode->i_sb->s_flags & MS_NODIRATIME) && S_ISDIR(inode->i_mode)) - return; + return false; if (mnt->mnt_flags & MNT_NOATIME) - return; + return false; if ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)) - return; + return false; now = current_fs_time(inode->i_sb); if (!relatime_need_update(mnt, inode, now)) - return; + return false; if (timespec_equal(&inode->i_atime, &now)) + return false; + + return true; +} + +void touch_atime(const struct path *path) +{ + struct vfsmount *mnt = path->mnt; + struct inode *inode = d_inode(path->dentry); + struct timespec now; + + if (!atime_needs_update(path, inode)) return; if (!sb_start_write_trylock(inode->i_sb)) return; - if (__mnt_want_write(mnt)) + if (__mnt_want_write(mnt) != 0) goto skip_update; /* * File systems can error out when updating inodes if they need to @@ -1624,6 +1654,7 @@ void touch_atime(const struct path *path) * We may also fail on filesystems that have the ability to make parts * of the fs read only, e.g. subvolumes in Btrfs. */ + now = current_fs_time(inode->i_sb); update_time(inode, &now, S_ATIME); __mnt_drop_write(mnt); skip_update: @@ -1660,7 +1691,31 @@ int should_remove_suid(struct dentry *dentry) } EXPORT_SYMBOL(should_remove_suid); -static int __remove_suid(struct dentry *dentry, int kill) +/* + * Return mask of changes for notify_change() that need to be done as a + * response to write or truncate. Return 0 if nothing has to be changed. + * Negative value on error (change should be denied). + */ +int dentry_needs_remove_privs(struct dentry *dentry) +{ + struct inode *inode = d_inode(dentry); + int mask = 0; + int ret; + + if (IS_NOSEC(inode)) + return 0; + + mask = should_remove_suid(dentry); + ret = security_inode_need_killpriv(dentry); + if (ret < 0) + return ret; + if (ret) + mask |= ATTR_KILL_PRIV; + return mask; +} +EXPORT_SYMBOL(dentry_needs_remove_privs); + +static int __remove_privs(struct dentry *dentry, int kill) { struct iattr newattrs; @@ -1672,33 +1727,32 @@ static int __remove_suid(struct dentry *dentry, int kill) return notify_change(dentry, &newattrs, NULL); } -int file_remove_suid(struct file *file) +/* + * Remove special file priviledges (suid, capabilities) when file is written + * to or truncated. + */ +int file_remove_privs(struct file *file) { struct dentry *dentry = file->f_path.dentry; struct inode *inode = d_inode(dentry); - int killsuid; - int killpriv; + int kill; 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); + kill = file_needs_remove_privs(file); + if (kill < 0) + return kill; + if (kill) + error = __remove_privs(dentry, kill); if (!error) inode_has_no_xattr(inode); return error; } -EXPORT_SYMBOL(file_remove_suid); +EXPORT_SYMBOL(file_remove_privs); /** * file_update_time - update mtime and ctime time @@ -1953,9 +2007,8 @@ EXPORT_SYMBOL(inode_dio_wait); * inode is being instantiated). The reason for the cmpxchg() loop * --- which wouldn't be necessary if all code paths which modify * i_flags actually followed this rule, is that there is at least one - * code path which doesn't today --- for example, - * __generic_file_aio_write() calls file_remove_suid() without holding - * i_mutex --- so we use cmpxchg() out of an abundance of caution. + * code path which doesn't today so we use cmpxchg() out of an abundance + * of caution. * * In the long run, i_mutex is overkill, and we should probably look * at using the i_lock spinlock to protect i_flags, and then make sure