Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751330Ab3IGIg7 (ORCPT ); Sat, 7 Sep 2013 04:36:59 -0400 Received: from mail-ee0-f54.google.com ([74.125.83.54]:43791 "EHLO mail-ee0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751121Ab3IGIg4 (ORCPT ); Sat, 7 Sep 2013 04:36:56 -0400 Message-ID: <522AE403.7070103@gmail.com> Date: Sat, 07 Sep 2013 10:29:55 +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: Vladimir Davydov , linux-kernel@vger.kernel.org Subject: [PATCH 13/19] pramfs: xip operations 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: 4499 Lines: 181 Add xip operations. Signed-off-by: Marco Stornelli --- fs/pramfs/xip.c | 119 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/pramfs/xip.h | 33 +++++++++++++++ 2 files changed, 152 insertions(+), 0 deletions(-) create mode 100644 fs/pramfs/xip.c create mode 100644 fs/pramfs/xip.h diff --git a/fs/pramfs/xip.c b/fs/pramfs/xip.c new file mode 100644 index 0000000..26b8afe --- /dev/null +++ b/fs/pramfs/xip.c @@ -0,0 +1,119 @@ +/* + * BRIEF DESCRIPTION + * + * XIP operations. + * + * Copyright 2009-2011 Marco Stornelli + * 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 +#include "pram.h" +#include "xip.h" + +/* + * Wrappers. We need to use the rcu read lock to avoid + * concurrent truncate operation. No problem for write because we held + * i_mutex. + */ +ssize_t pram_xip_file_read(struct file *filp, char __user *buf, + size_t len, loff_t *ppos) +{ + ssize_t res; + rcu_read_lock(); + res = xip_file_read(filp, buf, len, ppos); + rcu_read_unlock(); + return res; +} + +static int pram_xip_file_fault(struct vm_area_struct *vma, struct vm_fault *vmf) +{ + int ret = 0; + rcu_read_lock(); + ret = xip_file_fault(vma, vmf); + rcu_read_unlock(); + return ret; +} + +static const struct vm_operations_struct pram_xip_vm_ops = { + .fault = pram_xip_file_fault, + .page_mkwrite = filemap_page_mkwrite, + .remap_pages = generic_file_remap_pages, +}; + +int pram_xip_file_mmap(struct file * file, struct vm_area_struct * vma) +{ + BUG_ON(!file->f_mapping->a_ops->get_xip_mem); + + file_accessed(file); + vma->vm_ops = &pram_xip_vm_ops; + vma->vm_flags |= VM_MIXEDMAP; + return 0; +} + +static int pram_find_and_alloc_blocks(struct inode *inode, sector_t iblock, + sector_t *data_block, int create) +{ + int err = -EIO; + u64 block; + + block = pram_find_data_block(inode, iblock); + + if (!block) { + if (!create) { + err = -ENODATA; + goto err; + } + + err = pram_alloc_blocks(inode, iblock, 1); + if (err) + goto err; + + block = pram_find_data_block(inode, iblock); + if (!block) { + err = -ENODATA; + goto err; + } + } + + *data_block = block; + err = 0; + + err: + return err; +} + +static inline int __pram_get_block(struct inode *inode, pgoff_t pgoff, + int create, sector_t *result) +{ + int rc = 0; + + rc = pram_find_and_alloc_blocks(inode, (sector_t)pgoff, result, create); + + if (rc == -ENODATA) + BUG_ON(create); + + return rc; +} + +int pram_get_xip_mem(struct address_space *mapping, pgoff_t pgoff, int create, + void **kmem, unsigned long *pfn) +{ + int rc; + sector_t block = 0; + + /* first, retrieve the block */ + rc = __pram_get_block(mapping->host, pgoff, create, &block); + if (rc) + goto exit; + + *kmem = pram_get_block(mapping->host->i_sb, block); + *pfn = pram_get_pfn(mapping->host->i_sb, block); + +exit: + return rc; +} diff --git a/fs/pramfs/xip.h b/fs/pramfs/xip.h new file mode 100644 index 0000000..5bd82f2 --- /dev/null +++ b/fs/pramfs/xip.h @@ -0,0 +1,33 @@ +/* + * BRIEF DESCRIPTION + * + * XIP operations. + * + * Copyright 2009-2011 Marco Stornelli + * 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. + */ + +#ifdef CONFIG_PRAMFS_XIP +int pram_get_xip_mem(struct address_space *, pgoff_t, int, void **, + unsigned long *); +ssize_t pram_xip_file_read(struct file *filp, char __user *buf, + size_t len, loff_t *ppos); +int pram_xip_file_mmap(struct file * file, struct vm_area_struct * vma); +static inline int pram_use_xip(struct super_block *sb) +{ + struct pram_sb_info *sbi = PRAM_SB(sb); + return sbi->s_mount_opt & PRAM_MOUNT_XIP; +} +#define mapping_is_xip(map) (map->a_ops->get_xip_mem) + +#else + +#define mapping_is_xip(map) 0 +#define pram_use_xip(sb) 0 +#define pram_get_xip_mem NULL +#define pram_xip_file_read NULL +#define pram_xip_file_mmap NULL + +#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/