/* * JFFS2 -- Journalling Flash File System, Version 2. * * Copyright (C) 2001-2003 Red Hat, Inc. * * Created by David Woodhouse <dwmw2@redhat.com> * * For licensing information, see the file 'LICENCE' in this directory. * * $Id: file.c,v 1.98 2004/03/19 16:41:09 dwmw2 Exp $ * */#include <linux/version.h>#include <linux/kernel.h>#include <linux/slab.h>#include <linux/fs.h>#include <linux/time.h>#include <linux/pagemap.h>#include <linux/highmem.h>#include <linux/crc32.h>#include <linux/jffs2.h>#include "nodelist.h"extern int generic_file_open(struct inode *, struct file *) __attribute__((weak));extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) __attribute__((weak));int jffs2_fsync(struct file *filp, struct dentry *dentry, int datasync){	struct inode *inode = dentry->d_inode;	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);	/* Trigger GC to flush any pending writes for this inode */	jffs2_flush_wbuf_gc(c, inode->i_ino);				return 0;	}struct file_operations jffs2_file_operations ={	.llseek =	generic_file_llseek,	.open =		generic_file_open,	.read =		generic_file_read,	.write =	generic_file_write,	.ioctl =	jffs2_ioctl,	.mmap =		generic_file_readonly_mmap,	.fsync =	jffs2_fsync,#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,29)	.sendfile =	generic_file_sendfile#endif};/* jffs2_file_inode_operations */struct inode_operations jffs2_file_inode_operations ={	.setattr =	jffs2_setattr};struct address_space_operations jffs2_file_address_operations ={	.readpage =	jffs2_readpage,	.prepare_write =jffs2_prepare_write,	.commit_write =	jffs2_commit_write};int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg){	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);	unsigned char *pg_buf;	int ret;	D2(printk(KERN_DEBUG "jffs2_do_readpage_nolock(): ino #%lu, page at offset 0x%lx\n", inode->i_ino, pg->index << PAGE_CACHE_SHIFT));	if (!PageLocked(pg))                PAGE_BUG(pg);	pg_buf = kmap(pg);	/* FIXME: Can kmap fail? */	ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE);	if (ret) {		ClearPageUptodate(pg);		SetPageError(pg);	} else {		SetPageUptodate(pg);		ClearPageError(pg);	}	flush_dcache_page(pg);	kunmap(pg);	D2(printk(KERN_DEBUG "readpage finished\n"));	return 0;}int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg){	int ret = jffs2_do_readpage_nolock(inode, pg);	unlock_page(pg);	return ret;}int jffs2_readpage (struct file *filp, struct page *pg){	struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host);	int ret;		down(&f->sem);	ret = jffs2_do_readpage_unlock(pg->mapping->host, pg);	up(&f->sem);	return ret;}int jffs2_prepare_write (struct file *filp, struct page *pg, unsigned start, unsigned end){	struct inode *inode = pg->mapping->host;	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);	uint32_t pageofs = pg->index << PAGE_CACHE_SHIFT;	int ret = 0;	D1(printk(KERN_DEBUG "jffs2_prepare_write()\n"));	if (pageofs > inode->i_size) {		/* Make new hole frag from old EOF to new page */		struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);		struct jffs2_raw_inode ri;		struct jffs2_full_dnode *fn;		uint32_t phys_ofs, alloc_len;				D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",			  (unsigned int)inode->i_size, pageofs));		ret = jffs2_reserve_space(c, sizeof(ri), &phys_ofs, &alloc_len, ALLOC_NORMAL);		if (ret)			return ret;		down(&f->sem);		memset(&ri, 0, sizeof(ri));		ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);		ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);		ri.totlen = cpu_to_je32(sizeof(ri));		ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));		ri.ino = cpu_to_je32(f->inocache->ino);		ri.version = cpu_to_je32(++f->highest_version);		ri.mode = cpu_to_jemode(inode->i_mode);		ri.uid = cpu_to_je16(inode->i_uid);		ri.gid = cpu_to_je16(inode->i_gid);		ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));		ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds());		ri.offset = cpu_to_je32(inode->i_size);		ri.dsize = cpu_to_je32(pageofs - inode->i_size);		ri.csize = cpu_to_je32(0);		ri.compr = JFFS2_COMPR_ZERO;		ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));		ri.data_crc = cpu_to_je32(0);				fn = jffs2_write_dnode(c, f, &ri, NULL, 0, phys_ofs, ALLOC_NORMAL);		if (IS_ERR(fn)) {			ret = PTR_ERR(fn);			jffs2_complete_reservation(c);			up(&f->sem);			return ret;		}		ret = jffs2_add_full_dnode_to_inode(c, f, fn);		if (f->metadata) {			jffs2_mark_node_obsolete(c, f->metadata->raw);			jffs2_free_full_dnode(f->metadata);			f->metadata = NULL;		}		if (ret) {			D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in prepare_write, returned %d\n", ret));			jffs2_mark_node_obsolete(c, fn->raw);			jffs2_free_full_dnode(fn);			jffs2_complete_reservation(c);			up(&f->sem);			return ret;		}		jffs2_complete_reservation(c);		inode->i_size = pageofs;		up(&f->sem);	}		/* Read in the page if it wasn't already present, unless it's a whole page */	if (!PageUptodate(pg) && (start || end < PAGE_CACHE_SIZE)) {		down(&f->sem);		ret = jffs2_do_readpage_nolock(inode, pg);		up(&f->sem);	}	D1(printk(KERN_DEBUG "end prepare_write(). pg->flags %lx\n", pg->flags));	return ret;}int jffs2_commit_write (struct file *filp, struct page *pg, unsigned start, unsigned end){	/* Actually commit the write from the page cache page we're looking at.	 * For now, we write the full page out each time. It sucks, but it's simple	 */	struct inode *inode = pg->mapping->host;	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);	struct jffs2_raw_inode *ri;	unsigned aligned_start = start & ~3;	int ret = 0;	uint32_t writtenlen = 0;	D1(printk(KERN_DEBUG "jffs2_commit_write(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n",		  inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, pg->flags));	if (!start && end == PAGE_CACHE_SIZE) {		/* We need to avoid deadlock with page_cache_read() in		   jffs2_garbage_collect_pass(). So we have to mark the		   page up to date, to prevent page_cache_read() from 		   trying to re-lock it. */		SetPageUptodate(pg);	}	ri = jffs2_alloc_raw_inode();	if (!ri) {		D1(printk(KERN_DEBUG "jffs2_commit_write(): Allocation of raw inode failed\n"));		return -ENOMEM;	}	/* Set the fields that the generic jffs2_write_inode_range() code can't find */	ri->ino = cpu_to_je32(inode->i_ino);	ri->mode = cpu_to_jemode(inode->i_mode);	ri->uid = cpu_to_je16(inode->i_uid);	ri->gid = cpu_to_je16(inode->i_gid);	ri->isize = cpu_to_je32((uint32_t)inode->i_size);	ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds());	/* In 2.4, it was already kmapped by generic_file_write(). Doesn't	   hurt to do it again. The alternative is ifdefs, which are ugly. */	kmap(pg);	ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start,				      (pg->index << PAGE_CACHE_SHIFT) + aligned_start,				      end - aligned_start, &writtenlen);	kunmap(pg);	if (ret) {		/* There was an error writing. */		SetPageError(pg);	}		/* Adjust writtenlen for the padding we did, so we don't confuse our caller */	if (writtenlen < (start&3))		writtenlen = 0;	else		writtenlen -= (start&3);	if (writtenlen) {		if (inode->i_size < (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen) {			inode->i_size = (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen;			inode->i_blocks = (inode->i_size + 511) >> 9;						inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime));		}	}	jffs2_free_raw_inode(ri);	if (start+writtenlen < end) {		/* generic_file_write has written more to the page cache than we've		   actually written to the medium. Mark the page !Uptodate so that 		   it gets reread */		D1(printk(KERN_DEBUG "jffs2_commit_write(): Not all bytes written. Marking page !uptodate\n"));		SetPageError(pg);		ClearPageUptodate(pg);	}	D1(printk(KERN_DEBUG "jffs2_commit_write() returning %d\n",writtenlen?writtenlen:ret));	return writtenlen?writtenlen:ret;}