Subversion Repositories openrisc_me

/*

 * JFFS2 -- Journalling Flash File System, Version 2.

 *

 * Copyright (C) 2001, 2002 Red Hat, Inc.

 *

 * Created by David Woodhouse <dwmw2@cambridge.redhat.com>

 *

 * For licensing information, see the file 'LICENCE' in this directory.

 *

 * $Id: file-ecos.c,v 1.1.1.1 2004-02-14 13:29:20 phoenix Exp $

 *

 */

#include <linux/kernel.h>

#include <linux/pagemap.h>

#include <linux/crc32.h>

#include "nodelist.h"

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;

        D1(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 = (char *)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);

        D1(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);

        UnlockPage(pg);

        return ret;

}

//int jffs2_readpage (struct file *filp, struct page *pg)

int jffs2_readpage (struct inode *d_inode, struct page *pg)

{

        //      struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode);

        int ret;

        //      down(&f->sem);

        ret = jffs2_do_readpage_unlock(d_inode, pg);

        //      up(&f->sem);

        return ret;

}

//int jffs2_prepare_write (struct file *filp, struct page *pg, unsigned start, unsigned end)

int jffs2_prepare_write (struct inode *d_inode, struct page *pg, unsigned start, unsigned end)

{

        struct inode *inode = d_inode;

        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(cyg_timestamp());

                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, NULL);

                jffs2_complete_reservation(c);

                if (IS_ERR(fn)) {

                        ret = PTR_ERR(fn);

                        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);

                        up(&f->sem);

                        return ret;

                }

                inode->i_size = pageofs;

                up(&f->sem);

        }

        /* Read in the page if it wasn't already present, unless it's a whole page */

        // eCos has no concept of uptodate and by default always reads pages afresh

        if (!Page_Uptodate(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()\n"));

        return ret;

}

//int jffs2_commit_write (struct file *filp, struct page *pg, unsigned start, unsigned end)

int jffs2_commit_write (struct inode *d_inode, 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 = d_inode;

        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;

        int ret = 0;

        uint32_t writtenlen = 0;

        D1(printk(KERN_DEBUG "jffs2_commit_write(): ino #%lu, page at 0x%lx, range %d-%d\n",

                  inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end));

        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(cyg_timestamp());

        ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + start,

                                      (pg->index << PAGE_CACHE_SHIFT) + start,

                                      end - start, &writtenlen);

        if (ret) {

                /* There was an error writing. */

                SetPageError(pg);

        }

        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_ctime = inode->i_mtime = 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;

}