f2fs: readahead multi pages of directory for performance

[deliverable/linux.git] / fs / f2fs / dir.c

diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 7c9b17c0367581e4e7253e602b4e8f2b54e9cb0d..3581c2bde21b1f53ab2483b4df57c35ae6e88e19 100644 (file)
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -493,6 +493,7 @@ start:
 add_dentry:
        f2fs_wait_on_page_writeback(dentry_page, DATA);
 
+       down_write(&F2FS_I(inode)->i_sem);
        page = init_inode_metadata(inode, dir, name);
        if (IS_ERR(page)) {
                err = PTR_ERR(page);
@@ -515,6 +516,8 @@ add_dentry:
 
        update_parent_metadata(dir, inode, current_depth);
 fail:
+       up_write(&F2FS_I(inode)->i_sem);
+
        if (is_inode_flag_set(F2FS_I(dir), FI_UPDATE_DIR)) {
                update_inode_page(dir);
                clear_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
@@ -559,6 +562,8 @@ void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
        if (inode) {
                struct f2fs_sb_info *sbi = F2FS_SB(dir->i_sb);
 
+               down_write(&F2FS_I(inode)->i_sem);
+
                if (S_ISDIR(inode->i_mode)) {
                        drop_nlink(dir);
                        update_inode_page(dir);
@@ -569,6 +574,7 @@ void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
                        drop_nlink(inode);
                        i_size_write(inode, 0);
                }
+               up_write(&F2FS_I(inode)->i_sem);
                update_inode_page(inode);
 
                if (inode->i_nlink == 0)
@@ -631,11 +637,17 @@ static int f2fs_readdir(struct file *file, struct dir_context *ctx)
        struct f2fs_dentry_block *dentry_blk = NULL;
        struct f2fs_dir_entry *de = NULL;
        struct page *dentry_page = NULL;
+       struct file_ra_state *ra = &file->f_ra;
        unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
        unsigned char d_type = DT_UNKNOWN;
 
        bit_pos = ((unsigned long)ctx->pos % NR_DENTRY_IN_BLOCK);
 
+       /* readahead for multi pages of dir */
+       if (npages - n > 1 && !ra_has_index(ra, n))
+               page_cache_sync_readahead(inode->i_mapping, ra, file, n,
+                               min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES));
+
        for (; n < npages; n++) {
                dentry_page = get_lock_data_page(inode, n);
                if (IS_ERR(dentry_page))