Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 *   Copyright (C) International Business Machines Corp., 2000-2004

 *   Portions Copyright (C) Christoph Hellwig, 2001-2002

 *

 *   This program is free software;  you can redistribute it and/or modify

 *   it under the terms of the GNU General Public License as published by

 *   the Free Software Foundation; either version 2 of the License, or

 *   (at your option) any later version.

 *

 *   This program is distributed in the hope that it will be useful,

 *   but WITHOUT ANY WARRANTY;  without even the implied warranty of

 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See

 *   the GNU General Public License for more details.

 *

 *   You should have received a copy of the GNU General Public License

 *   along with this program;  if not, write to the Free Software

 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

 */

#include <linux/fs.h>

#include <linux/mpage.h>

#include <linux/buffer_head.h>

#include <linux/pagemap.h>

#include <linux/quotaops.h>

#include "jfs_incore.h"

#include "jfs_inode.h"

#include "jfs_filsys.h"

#include "jfs_imap.h"

#include "jfs_extent.h"

#include "jfs_unicode.h"

#include "jfs_debug.h"

void jfs_read_inode(struct inode *inode)

{

        if (diRead(inode)) {

                make_bad_inode(inode);

                return;

        }

        if (S_ISREG(inode->i_mode)) {

                inode->i_op = &jfs_file_inode_operations;

                inode->i_fop = &jfs_file_operations;

                inode->i_mapping->a_ops = &jfs_aops;

        } else if (S_ISDIR(inode->i_mode)) {

                inode->i_op = &jfs_dir_inode_operations;

                inode->i_fop = &jfs_dir_operations;

        } else if (S_ISLNK(inode->i_mode)) {

                if (inode->i_size >= IDATASIZE) {

                        inode->i_op = &page_symlink_inode_operations;

                        inode->i_mapping->a_ops = &jfs_aops;

                } else

                        inode->i_op = &jfs_symlink_inode_operations;

        } else {

                inode->i_op = &jfs_file_inode_operations;

                init_special_inode(inode, inode->i_mode, inode->i_rdev);

        }

}

/*

 * Workhorse of both fsync & write_inode

 */

int jfs_commit_inode(struct inode *inode, int wait)

{

        int rc = 0;

        tid_t tid;

        static int noisy = 5;

        jfs_info("In jfs_commit_inode, inode = 0x%p", inode);

        /*

         * Don't commit if inode has been committed since last being

         * marked dirty, or if it has been deleted.

         */

        if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode))

                return 0;

        if (isReadOnly(inode)) {

                /* kernel allows writes to devices on read-only

                 * partitions and may think inode is dirty

                 */

                if (!special_file(inode->i_mode) && noisy) {

                        jfs_err("jfs_commit_inode(0x%p) called on "

                                   "read-only volume", inode);

                        jfs_err("Is remount racy?");

                        noisy--;

                }

                return 0;

        }

        tid = txBegin(inode->i_sb, COMMIT_INODE);

        mutex_lock(&JFS_IP(inode)->commit_mutex);

        /*

         * Retest inode state after taking commit_mutex

         */

        if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode))

                rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0);

        txEnd(tid);

        mutex_unlock(&JFS_IP(inode)->commit_mutex);

        return rc;

}

int jfs_write_inode(struct inode *inode, int wait)

{

        if (test_cflag(COMMIT_Nolink, inode))

                return 0;

        /*

         * If COMMIT_DIRTY is not set, the inode isn't really dirty.

         * It has been committed since the last change, but was still

         * on the dirty inode list.

         */

         if (!test_cflag(COMMIT_Dirty, inode)) {

                /* Make sure committed changes hit the disk */

                jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait);

                return 0;

         }

        if (jfs_commit_inode(inode, wait)) {

                jfs_err("jfs_write_inode: jfs_commit_inode failed!");

                return -EIO;

        } else

                return 0;

}

void jfs_delete_inode(struct inode *inode)

{

        jfs_info("In jfs_delete_inode, inode = 0x%p", inode);

        if (!is_bad_inode(inode) &&

            (JFS_IP(inode)->fileset == FILESYSTEM_I)) {

                truncate_inode_pages(&inode->i_data, 0);

                if (test_cflag(COMMIT_Freewmap, inode))

                        jfs_free_zero_link(inode);

                diFree(inode);

                /*

                 * Free the inode from the quota allocation.

                 */

                DQUOT_INIT(inode);

                DQUOT_FREE_INODE(inode);

                DQUOT_DROP(inode);

        }

        clear_inode(inode);

}

void jfs_dirty_inode(struct inode *inode)

{

        static int noisy = 5;

        if (isReadOnly(inode)) {

                if (!special_file(inode->i_mode) && noisy) {

                        /* kernel allows writes to devices on read-only

                         * partitions and may try to mark inode dirty

                         */

                        jfs_err("jfs_dirty_inode called on read-only volume");

                        jfs_err("Is remount racy?");

                        noisy--;

                }

                return;

        }

        set_cflag(COMMIT_Dirty, inode);

}

int jfs_get_block(struct inode *ip, sector_t lblock,

                  struct buffer_head *bh_result, int create)

{

        s64 lblock64 = lblock;

        int rc = 0;

        xad_t xad;

        s64 xaddr;

        int xflag;

        s32 xlen = bh_result->b_size >> ip->i_blkbits;

        /*

         * Take appropriate lock on inode

         */

        if (create)

                IWRITE_LOCK(ip, RDWRLOCK_NORMAL);

        else

                IREAD_LOCK(ip, RDWRLOCK_NORMAL);

        if (((lblock64 << ip->i_sb->s_blocksize_bits) < ip->i_size) &&

            (!xtLookup(ip, lblock64, xlen, &xflag, &xaddr, &xlen, 0)) &&

            xaddr) {

                if (xflag & XAD_NOTRECORDED) {

                        if (!create)

                                /*

                                 * Allocated but not recorded, read treats

                                 * this as a hole

                                 */

                                goto unlock;

#ifdef _JFS_4K

                        XADoffset(&xad, lblock64);

                        XADlength(&xad, xlen);

                        XADaddress(&xad, xaddr);

#else                           /* _JFS_4K */

                        /*

                         * As long as block size = 4K, this isn't a problem.

                         * We should mark the whole page not ABNR, but how

                         * will we know to mark the other blocks BH_New?

                         */

                        BUG();

#endif                          /* _JFS_4K */

                        rc = extRecord(ip, &xad);

                        if (rc)

                                goto unlock;

                        set_buffer_new(bh_result);

                }

                map_bh(bh_result, ip->i_sb, xaddr);

                bh_result->b_size = xlen << ip->i_blkbits;

                goto unlock;

        }

        if (!create)

                goto unlock;

        /*

         * Allocate a new block

         */

#ifdef _JFS_4K

        if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad)))

                goto unlock;

        rc = extAlloc(ip, xlen, lblock64, &xad, false);

        if (rc)

                goto unlock;

        set_buffer_new(bh_result);

        map_bh(bh_result, ip->i_sb, addressXAD(&xad));

        bh_result->b_size = lengthXAD(&xad) << ip->i_blkbits;

#else                           /* _JFS_4K */

        /*

         * We need to do whatever it takes to keep all but the last buffers

         * in 4K pages - see jfs_write.c

         */

        BUG();

#endif                          /* _JFS_4K */

      unlock:

        /*

         * Release lock on inode

         */

        if (create)

                IWRITE_UNLOCK(ip);

        else

                IREAD_UNLOCK(ip);

        return rc;

}

static int jfs_writepage(struct page *page, struct writeback_control *wbc)

{

        return block_write_full_page(page, jfs_get_block, wbc);

}

static int jfs_writepages(struct address_space *mapping,

                        struct writeback_control *wbc)

{

        return mpage_writepages(mapping, wbc, jfs_get_block);

}

static int jfs_readpage(struct file *file, struct page *page)

{

        return mpage_readpage(page, jfs_get_block);

}

static int jfs_readpages(struct file *file, struct address_space *mapping,

                struct list_head *pages, unsigned nr_pages)

{

        return mpage_readpages(mapping, pages, nr_pages, jfs_get_block);

}

static int jfs_write_begin(struct file *file, struct address_space *mapping,

                                loff_t pos, unsigned len, unsigned flags,

                                struct page **pagep, void **fsdata)

{

        return nobh_write_begin(file, mapping, pos, len, flags, pagep, fsdata,

                                jfs_get_block);

}

static sector_t jfs_bmap(struct address_space *mapping, sector_t block)

{

        return generic_block_bmap(mapping, block, jfs_get_block);

}

static ssize_t jfs_direct_IO(int rw, struct kiocb *iocb,

        const struct iovec *iov, loff_t offset, unsigned long nr_segs)

{

        struct file *file = iocb->ki_filp;

        struct inode *inode = file->f_mapping->host;

        return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,

                                offset, nr_segs, jfs_get_block, NULL);

}

const struct address_space_operations jfs_aops = {

        .readpage       = jfs_readpage,

        .readpages      = jfs_readpages,

        .writepage      = jfs_writepage,

        .writepages     = jfs_writepages,

        .sync_page      = block_sync_page,

        .write_begin    = jfs_write_begin,

        .write_end      = nobh_write_end,

        .bmap           = jfs_bmap,

        .direct_IO      = jfs_direct_IO,

};

/*

 * Guts of jfs_truncate.  Called with locks already held.  Can be called

 * with directory for truncating directory index table.

 */

void jfs_truncate_nolock(struct inode *ip, loff_t length)

{

        loff_t newsize;

        tid_t tid;

        ASSERT(length >= 0);

        if (test_cflag(COMMIT_Nolink, ip)) {

                xtTruncate(0, ip, length, COMMIT_WMAP);

                return;

        }

        do {

                tid = txBegin(ip->i_sb, 0);

                /*

                 * The commit_mutex cannot be taken before txBegin.

                 * txBegin may block and there is a chance the inode

                 * could be marked dirty and need to be committed

                 * before txBegin unblocks

                 */

                mutex_lock(&JFS_IP(ip)->commit_mutex);

                newsize = xtTruncate(tid, ip, length,

                                     COMMIT_TRUNCATE | COMMIT_PWMAP);

                if (newsize < 0) {

                        txEnd(tid);

                        mutex_unlock(&JFS_IP(ip)->commit_mutex);

                        break;

                }

                ip->i_mtime = ip->i_ctime = CURRENT_TIME;

                mark_inode_dirty(ip);

                txCommit(tid, 1, &ip, 0);

                txEnd(tid);

                mutex_unlock(&JFS_IP(ip)->commit_mutex);

        } while (newsize > length);     /* Truncate isn't always atomic */

}

void jfs_truncate(struct inode *ip)

{

        jfs_info("jfs_truncate: size = 0x%lx", (ulong) ip->i_size);

        nobh_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block);

        IWRITE_LOCK(ip, RDWRLOCK_NORMAL);

        jfs_truncate_nolock(ip, ip->i_size);

        IWRITE_UNLOCK(ip);

}