From: Marco Stornelli <marco.stornelli@xxxxxxxxx> XIP operations. Signed-off-by: Marco Stornelli <marco.stornelli@xxxxxxxxx> --- diff --git a/fs/pramfs/xip.c b/fs/pramfs/xip.c new file mode 100644 index 0000000..9ad8caf --- /dev/null +++ b/fs/pramfs/xip.c @@ -0,0 +1,83 @@ +/* + * BRIEF DESCRIPTION + * + * XIP operations. + * + * Copyright 2009-2010 Marco Stornelli <marco.stornelli@xxxxxxxxx> + * 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 <linux/mm.h> +#include <linux/fs.h> +#include <linux/genhd.h> +#include <linux/buffer_head.h> +#include "pram.h" +#include "xip.h" + +static int pram_find_and_alloc_blocks(struct inode *inode, sector_t iblock, + sector_t *data_block, int create) +{ + int err = -EIO; + u64 block; + + mutex_lock(&PRAM_I(inode)->truncate_mutex); + + 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: + mutex_unlock(&PRAM_I(inode)->truncate_mutex); + 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; + + /* 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 = page_to_pfn(virt_to_page((unsigned long)*kmem)); + +exit: + return rc; +} diff --git a/fs/pramfs/xip.h b/fs/pramfs/xip.h new file mode 100644 index 0000000..797f1b0 --- /dev/null +++ b/fs/pramfs/xip.h @@ -0,0 +1,28 @@ +/* + * BRIEF DESCRIPTION + * + * XIP operations. + * + * Copyright 2009-2010 Marco Stornelli <marco.stornelli@xxxxxxxxx> + * 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 *); +static inline int pram_use_xip(struct super_block *sb) +{ + struct pram_sb_info *sbi = (struct pram_sb_info *)sb->s_fs_info; + return sbi->s_mount_opt & PRAM_MOUNT_XIP; +} +#define mapping_is_xip(map) unlikely(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 + +#endif -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html