diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index 28e202e89660..26837c3ca7f6 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -220,6 +220,7 @@ struct btrfs_inode { /* Hook into fs_info->delayed_iputs */ struct list_head delayed_iput; + struct rw_semaphore i_mmap_lock; struct inode vfs_inode; }; diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 5776026c532e..751ab9f80e4c 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3178,6 +3178,7 @@ extern const struct iomap_dio_ops btrfs_dio_ops; /* Inode locking type flags, by default the exclusive lock is taken */ #define BTRFS_ILOCK_SHARED (1U << 0) #define BTRFS_ILOCK_TRY (1U << 1) +#define BTRFS_ILOCK_MMAP (1U << 2) int btrfs_inode_lock(struct inode *inode, unsigned int ilock_flags); void btrfs_inode_unlock(struct inode *inode, unsigned int ilock_flags); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index df38540d7550..93f735ca96cf 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -102,6 +102,7 @@ static void __endio_write_update_ordered(struct btrfs_inode *inode, * BTRFS_ILOCK_SHARED - acquire a shared lock on the inode * BTRFS_ILOCK_TRY - try to acquire the lock, if fails on first attempt * return -EAGAIN + * BTRFS_ILOCK_MMAP - acquire a write lock on the i_mmap_lock */ int btrfs_inode_lock(struct inode *inode, unsigned int ilock_flags) { @@ -122,6 +123,8 @@ int btrfs_inode_lock(struct inode *inode, unsigned int ilock_flags) } inode_lock(inode); } + if (ilock_flags & BTRFS_ILOCK_MMAP) + down_write(&BTRFS_I(inode)->i_mmap_lock); return 0; } @@ -133,6 +136,8 @@ int btrfs_inode_lock(struct inode *inode, unsigned int ilock_flags) */ void btrfs_inode_unlock(struct inode *inode, unsigned int ilock_flags) { + if (ilock_flags & BTRFS_ILOCK_MMAP) + up_write(&BTRFS_I(inode)->i_mmap_lock); if (ilock_flags & BTRFS_ILOCK_SHARED) inode_unlock_shared(inode); else @@ -8540,6 +8545,7 @@ vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */ again: + down_read(&BTRFS_I(inode)->i_mmap_lock); lock_page(page); size = i_size_read(inode); @@ -8568,6 +8574,7 @@ vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) unlock_extent_cached(io_tree, page_start, page_end, &cached_state); unlock_page(page); + up_read(&BTRFS_I(inode)->i_mmap_lock); btrfs_start_ordered_extent(ordered, 1); btrfs_put_ordered_extent(ordered); goto again; @@ -8625,6 +8632,7 @@ vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit; unlock_extent_cached(io_tree, page_start, page_end, &cached_state); + up_read(&BTRFS_I(inode)->i_mmap_lock); btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE); sb_end_pagefault(inode->i_sb); @@ -8633,6 +8641,7 @@ vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) out_unlock: unlock_page(page); + up_read(&BTRFS_I(inode)->i_mmap_lock); out: btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE); btrfs_delalloc_release_space(BTRFS_I(inode), data_reserved, page_start, @@ -8884,6 +8893,7 @@ struct inode *btrfs_alloc_inode(struct super_block *sb) INIT_LIST_HEAD(&ei->delalloc_inodes); INIT_LIST_HEAD(&ei->delayed_iput); RB_CLEAR_NODE(&ei->rb_node); + init_rwsem(&ei->i_mmap_lock); return inode; }