diff --git a/include/linux/fs.h b/include/linux/fs.h index 6abcd0b72ae0..1d1838de6882 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -478,6 +478,16 @@ static inline void i_mmap_unlock_write(struct address_space *mapping) up_write(&mapping->i_mmap_rwsem); } +static inline void i_mmap_lock_read(struct address_space *mapping) +{ + down_read(&mapping->i_mmap_rwsem); +} + +static inline void i_mmap_unlock_read(struct address_space *mapping) +{ + up_read(&mapping->i_mmap_rwsem); +} + /* * Might pages of this file be mapped into userspace? */ diff --git a/mm/rmap.c b/mm/rmap.c index 18247f89f1a8..14ad2b3b0f54 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1690,7 +1690,8 @@ static int rmap_walk_file(struct page *page, struct rmap_walk_control *rwc) if (!mapping) return ret; - i_mmap_lock_write(mapping); + + i_mmap_lock_read(mapping); vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) { unsigned long address = vma_address(page, vma); @@ -1711,9 +1712,8 @@ static int rmap_walk_file(struct page *page, struct rmap_walk_control *rwc) goto done; ret = rwc->file_nonlinear(page, mapping, rwc->arg); - done: - i_mmap_unlock_write(mapping); + i_mmap_unlock_read(mapping); return ret; }