Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751295Ab3IGI3k (ORCPT ); Sat, 7 Sep 2013 04:29:40 -0400 Received: from mail-ea0-f173.google.com ([209.85.215.173]:56617 "EHLO mail-ea0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751123Ab3IGI3h (ORCPT ); Sat, 7 Sep 2013 04:29:37 -0400 Message-ID: <522AE24C.6060903@gmail.com> Date: Sat, 07 Sep 2013 10:22:36 +0200 From: Marco Stornelli User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130620 Thunderbird/17.0.7 MIME-Version: 1.0 To: Linux FS Devel CC: linux-kernel@vger.kernel.org, Vladimir Davydov Subject: [PATCH 08/19] pramfs: file operations for dirs Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6853 Lines: 247 Add file operations for dirs. Signed-off-by: Marco Stornelli --- fs/pramfs/dir.c | 226 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 226 insertions(+), 0 deletions(-) create mode 100644 fs/pramfs/dir.c diff --git a/fs/pramfs/dir.c b/fs/pramfs/dir.c new file mode 100644 index 0000000..137a592 --- /dev/null +++ b/fs/pramfs/dir.c @@ -0,0 +1,226 @@ +/* + * BRIEF DESCRIPTION + * + * File operations for directories. + * + * Copyright 2009-2011 Marco Stornelli + * Copyright 2003 Sony Corporation + * Copyright 2003 Matsushita Electric Industrial Co., Ltd. + * 2003-2004 (c) MontaVista Software, Inc. , Steve Longerbeam + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include +#include +#include "pram.h" + +/* + * Parent is locked. + */ +int pram_add_link(struct dentry *dentry, struct inode *inode) +{ + struct inode *dir = dentry->d_parent->d_inode; + struct pram_inode *pidir, *pi, *pitail = NULL; + u64 tail_ino, prev_ino; + + const char *name = dentry->d_name.name; + + int namelen = min_t(unsigned int, dentry->d_name.len, PRAM_NAME_LEN); + + pidir = pram_get_inode(dir->i_sb, dir->i_ino); + + mutex_lock(&PRAM_I(dir)->i_link_mutex); + + pi = pram_get_inode(dir->i_sb, inode->i_ino); + + dir->i_mtime = dir->i_ctime = CURRENT_TIME; + + tail_ino = be64_to_cpu(pidir->i_type.dir.tail); + if (tail_ino != 0) { + pitail = pram_get_inode(dir->i_sb, tail_ino); + pram_memunlock_inode(dir->i_sb, pitail); + pitail->i_d.d_next = cpu_to_be64(inode->i_ino); + pram_memlock_inode(dir->i_sb, pitail); + + prev_ino = tail_ino; + + pram_memunlock_inode(dir->i_sb, pidir); + pidir->i_type.dir.tail = cpu_to_be64(inode->i_ino); + pidir->i_mtime = cpu_to_be32(dir->i_mtime.tv_sec); + pidir->i_ctime = cpu_to_be32(dir->i_ctime.tv_sec); + pram_memlock_inode(dir->i_sb, pidir); + } else { + /* the directory is empty */ + prev_ino = 0; + + pram_memunlock_inode(dir->i_sb, pidir); + pidir->i_type.dir.tail = cpu_to_be64(inode->i_ino); + pidir->i_type.dir.head = cpu_to_be64(inode->i_ino); + pidir->i_mtime = cpu_to_be32(dir->i_mtime.tv_sec); + pidir->i_ctime = cpu_to_be32(dir->i_ctime.tv_sec); + pram_memlock_inode(dir->i_sb, pidir); + } + + + pram_memunlock_inode(dir->i_sb, pi); + pi->i_d.d_prev = cpu_to_be64(prev_ino); + pi->i_d.d_parent = cpu_to_be64(dir->i_ino); + memcpy(pi->i_d.d_name, name, namelen); + pi->i_d.d_name[namelen] = '\0'; + pram_memlock_inode(dir->i_sb, pi); + mutex_unlock(&PRAM_I(dir)->i_link_mutex); + return 0; +} + +int pram_remove_link(struct inode *inode) +{ + struct super_block *sb = inode->i_sb; + struct pram_inode *prev = NULL; + struct pram_inode *next = NULL; + struct pram_inode *pidir, *pi; + struct inode *dir = NULL; + + pi = pram_get_inode(sb, inode->i_ino); + pidir = pram_get_inode(sb, be64_to_cpu(pi->i_d.d_parent)); + if (!pidir) + return -EACCES; + + dir = pram_iget(inode->i_sb, be64_to_cpu(pi->i_d.d_parent)); + if (IS_ERR(dir)) + return -EACCES; + mutex_lock(&PRAM_I(dir)->i_link_mutex); + + if (inode->i_ino == be64_to_cpu(pidir->i_type.dir.head)) { + /* first inode in directory */ + next = pram_get_inode(sb, be64_to_cpu(pi->i_d.d_next)); + + if (next) { + pram_memunlock_inode(sb, next); + next->i_d.d_prev = 0; + pram_memlock_inode(sb, next); + + pram_memunlock_inode(sb, pidir); + pidir->i_type.dir.head = pi->i_d.d_next; + } else { + pram_memunlock_inode(sb, pidir); + pidir->i_type.dir.head = 0; + pidir->i_type.dir.tail = 0; + } + pram_memlock_inode(sb, pidir); + } else if (inode->i_ino == be64_to_cpu(pidir->i_type.dir.tail)) { + /* last inode in directory */ + prev = pram_get_inode(sb, be64_to_cpu(pi->i_d.d_prev)); + + pram_memunlock_inode(sb, prev); + prev->i_d.d_next = 0; + pram_memlock_inode(sb, prev); + + pram_memunlock_inode(sb, pidir); + pidir->i_type.dir.tail = pi->i_d.d_prev; + pram_memlock_inode(sb, pidir); + } else { + /* somewhere in the middle */ + prev = pram_get_inode(sb, be64_to_cpu(pi->i_d.d_prev)); + next = pram_get_inode(sb, be64_to_cpu(pi->i_d.d_next)); + + if (prev && next) { + pram_memunlock_inode(sb, prev); + prev->i_d.d_next = pi->i_d.d_next; + pram_memlock_inode(sb, prev); + + pram_memunlock_inode(sb, next); + next->i_d.d_prev = pi->i_d.d_prev; + pram_memlock_inode(sb, next); + } + } + + pram_memunlock_inode(sb, pi); + pi->i_d.d_next = 0; + pi->i_d.d_prev = 0; + pi->i_d.d_parent = 0; + pram_memlock_inode(sb, pi); + mutex_unlock(&PRAM_I(dir)->i_link_mutex); + iput(dir); + + return 0; +} + +#define DT2IF(dt) (((dt) << 12) & S_IFMT) +#define IF2DT(sif) (((sif) & S_IFMT) >> 12) + +static int pram_readdir(struct file *file, struct dir_context *ctx) +{ + struct inode *inode = file_inode(file); + struct super_block *sb = inode->i_sb; + struct pram_inode *pi; + int namelen, ret = 0; + char *name; + ino_t ino; + + pi = pram_get_inode(sb, inode->i_ino); + + switch ((u32)file->f_pos) { + case 0: + ret = dir_emit_dot(file, ctx); + ctx->pos = 1; + return ret; + case 1: + ret = dir_emit(ctx, "..", 2, be64_to_cpu(pi->i_d.d_parent), + DT_DIR); + mutex_lock(&PRAM_I(inode)->i_link_mutex); + ino = be64_to_cpu(pi->i_type.dir.head); + mutex_unlock(&PRAM_I(inode)->i_link_mutex); + ctx->pos = ino ? ino : 2; + return ret; + case 2: + mutex_lock(&PRAM_I(inode)->i_link_mutex); + ino = be64_to_cpu(pi->i_type.dir.head); + if (ino) { + ctx->pos = ino; + pi = pram_get_inode(sb, ino); + break; + } else { + /* the directory is empty */ + ctx->pos = 2; + mutex_unlock(&PRAM_I(inode)->i_link_mutex); + return 0; + } + case 3: + return 0; + default: + mutex_lock(&PRAM_I(inode)->i_link_mutex); + ino = file->f_pos; + pi = pram_get_inode(sb, ino); + break; + } + + while (pi && !be16_to_cpu(pi->i_links_count)) { + ino = ctx->pos = be64_to_cpu(pi->i_d.d_next); + pi = pram_get_inode(sb, ino); + } + + if (pi) { + name = pi->i_d.d_name; + namelen = strlen(name); + + ret = dir_emit(ctx, name, namelen, + ino, IF2DT(be16_to_cpu(pi->i_mode))); + ctx->pos = pi->i_d.d_next ? be64_to_cpu(pi->i_d.d_next) : 3; + } else + ctx->pos = 3; + + mutex_unlock(&PRAM_I(inode)->i_link_mutex); + return ret; +} + +const struct file_operations pram_dir_operations = { + .read = generic_read_dir, + .iterate = pram_readdir, + .fsync = noop_fsync, + .unlocked_ioctl = pram_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = pram_compat_ioctl, +#endif +}; -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/