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root/fs/ufs/util.c

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DEFINITIONS

This source file includes following definitions.
  1. _ubh_bread_
  2. ubh_bread_uspi
  3. ubh_brelse
  4. ubh_brelse_uspi
  5. ubh_mark_buffer_dirty
  6. ubh_mark_buffer_uptodate
  7. ubh_ll_rw_block
  8. ubh_wait_on_buffer
  9. ubh_bforget
  10. ubh_buffer_dirty
  11. _ubh_ubhcpymem_
  12. _ubh_memcpyubh_
  13. ufs_get_inode_dev
  14. ufs_set_inode_dev
  15. ufs_get_locked_page

/*
 *  linux/fs/ufs/util.c
 *
 * Copyright (C) 1998
 * Daniel Pirkl <daniel.pirkl@email.cz>
 * Charles University, Faculty of Mathematics and Physics
 */
 
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/buffer_head.h>

#include "ufs_fs.h"
#include "ufs.h"
#include "swab.h"
#include "util.h"

struct ufs_buffer_head * _ubh_bread_ (struct ufs_sb_private_info * uspi,
        struct super_block *sb, u64 fragment, u64 size)
{
        struct ufs_buffer_head * ubh;
        unsigned i, j ;
        u64  count = 0;
        if (size & ~uspi->s_fmask)
                return NULL;
        count = size >> uspi->s_fshift;
        if (count > UFS_MAXFRAG)
                return NULL;
        ubh = (struct ufs_buffer_head *)
                kmalloc (sizeof (struct ufs_buffer_head), GFP_KERNEL);
        if (!ubh)
                return NULL;
        ubh->fragment = fragment;
        ubh->count = count;
        for (i = 0; i < count; i++)
                if (!(ubh->bh[i] = sb_bread(sb, fragment + i)))
                        goto failed;
        for (; i < UFS_MAXFRAG; i++)
                ubh->bh[i] = NULL;
        return ubh;
failed:
        for (j = 0; j < i; j++)
                brelse (ubh->bh[j]);
        kfree(ubh);
        return NULL;
}

struct ufs_buffer_head * ubh_bread_uspi (struct ufs_sb_private_info * uspi,
        struct super_block *sb, u64 fragment, u64 size)
{
        unsigned i, j;
        u64 count = 0;
        if (size & ~uspi->s_fmask)
                return NULL;
        count = size >> uspi->s_fshift;
        if (count <= 0 || count > UFS_MAXFRAG)
                return NULL;
        USPI_UBH(uspi)->fragment = fragment;
        USPI_UBH(uspi)->count = count;
        for (i = 0; i < count; i++)
                if (!(USPI_UBH(uspi)->bh[i] = sb_bread(sb, fragment + i)))
                        goto failed;
        for (; i < UFS_MAXFRAG; i++)
                USPI_UBH(uspi)->bh[i] = NULL;
        return USPI_UBH(uspi);
failed:
        for (j = 0; j < i; j++)
                brelse (USPI_UBH(uspi)->bh[j]);
        return NULL;
}

void ubh_brelse (struct ufs_buffer_head * ubh)
{
        unsigned i;
        if (!ubh)
                return;
        for (i = 0; i < ubh->count; i++)
                brelse (ubh->bh[i]);
        kfree (ubh);
}

void ubh_brelse_uspi (struct ufs_sb_private_info * uspi)
{
        unsigned i;
        if (!USPI_UBH(uspi))
                return;
        for ( i = 0; i < USPI_UBH(uspi)->count; i++ ) {
                brelse (USPI_UBH(uspi)->bh[i]);
                USPI_UBH(uspi)->bh[i] = NULL;
        }
}

void ubh_mark_buffer_dirty (struct ufs_buffer_head * ubh)
{
        unsigned i;
        if (!ubh)
                return;
        for ( i = 0; i < ubh->count; i++ )
                mark_buffer_dirty (ubh->bh[i]);
}

void ubh_mark_buffer_uptodate (struct ufs_buffer_head * ubh, int flag)
{
        unsigned i;
        if (!ubh)
                return;
        if (flag) {
                for ( i = 0; i < ubh->count; i++ )
                        set_buffer_uptodate (ubh->bh[i]);
        } else {
                for ( i = 0; i < ubh->count; i++ )
                        clear_buffer_uptodate (ubh->bh[i]);
        }
}

void ubh_ll_rw_block(int rw, struct ufs_buffer_head *ubh)
{
        if (!ubh)
                return;

        ll_rw_block(rw, ubh->count, ubh->bh);
}

void ubh_wait_on_buffer (struct ufs_buffer_head * ubh)
{
        unsigned i;
        if (!ubh)
                return;
        for ( i = 0; i < ubh->count; i++ )
                wait_on_buffer (ubh->bh[i]);
}

void ubh_bforget (struct ufs_buffer_head * ubh)
{
        unsigned i;
        if (!ubh) 
                return;
        for ( i = 0; i < ubh->count; i++ ) if ( ubh->bh[i] ) 
                bforget (ubh->bh[i]);
}
 
int ubh_buffer_dirty (struct ufs_buffer_head * ubh)
{
        unsigned i;
        unsigned result = 0;
        if (!ubh)
                return 0;
        for ( i = 0; i < ubh->count; i++ )
                result |= buffer_dirty(ubh->bh[i]);
        return result;
}

void _ubh_ubhcpymem_(struct ufs_sb_private_info * uspi, 
        unsigned char * mem, struct ufs_buffer_head * ubh, unsigned size)
{
        unsigned len, bhno;
        if (size > (ubh->count << uspi->s_fshift))
                size = ubh->count << uspi->s_fshift;
        bhno = 0;
        while (size) {
                len = min_t(unsigned int, size, uspi->s_fsize);
                memcpy (mem, ubh->bh[bhno]->b_data, len);
                mem += uspi->s_fsize;
                size -= len;
                bhno++;
        }
}

void _ubh_memcpyubh_(struct ufs_sb_private_info * uspi, 
        struct ufs_buffer_head * ubh, unsigned char * mem, unsigned size)
{
        unsigned len, bhno;
        if (size > (ubh->count << uspi->s_fshift))
                size = ubh->count << uspi->s_fshift;
        bhno = 0;
        while (size) {
                len = min_t(unsigned int, size, uspi->s_fsize);
                memcpy (ubh->bh[bhno]->b_data, mem, len);
                mem += uspi->s_fsize;
                size -= len;
                bhno++;
        }
}

dev_t
ufs_get_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi)
{
        __u32 fs32;
        dev_t dev;

        if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
                fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[1]);
        else
                fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[0]);
        switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
        case UFS_ST_SUNx86:
        case UFS_ST_SUN:
                if ((fs32 & 0xffff0000) == 0 ||
                    (fs32 & 0xffff0000) == 0xffff0000)
                        dev = old_decode_dev(fs32 & 0x7fff);
                else
                        dev = MKDEV(sysv_major(fs32), sysv_minor(fs32));
                break;

        default:
                dev = old_decode_dev(fs32);
                break;
        }
        return dev;
}

void
ufs_set_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi, dev_t dev)
{
        __u32 fs32;

        switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
        case UFS_ST_SUNx86:
        case UFS_ST_SUN:
                fs32 = sysv_encode_dev(dev);
                if ((fs32 & 0xffff8000) == 0) {
                        fs32 = old_encode_dev(dev);
                }
                break;

        default:
                fs32 = old_encode_dev(dev);
                break;
        }
        if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
                ufsi->i_u1.i_data[1] = cpu_to_fs32(sb, fs32);
        else
                ufsi->i_u1.i_data[0] = cpu_to_fs32(sb, fs32);
}

/**
 * ufs_get_locked_page() - locate, pin and lock a pagecache page, if not exist
 * read it from disk.
 * @mapping: the address_space to search
 * @index: the page index
 *
 * Locates the desired pagecache page, if not exist we'll read it,
 * locks it, increments its reference
 * count and returns its address.
 *
 */

struct page *ufs_get_locked_page(struct address_space *mapping,
                                 pgoff_t index)
{
        struct page *page;

        page = find_lock_page(mapping, index);
        if (!page) {
                page = read_mapping_page(mapping, index, NULL);

                if (IS_ERR(page)) {
                        printk(KERN_ERR "ufs_change_blocknr: "
                               "read_mapping_page error: ino %lu, index: %lu\n",
                               mapping->host->i_ino, index);
                        goto out;
                }

                lock_page(page);

                if (unlikely(page->mapping == NULL)) {
                        /* Truncate got there first */
                        unlock_page(page);
                        page_cache_release(page);
                        page = NULL;
                        goto out;
                }

                if (!PageUptodate(page) || PageError(page)) {
                        unlock_page(page);
                        page_cache_release(page);

                        printk(KERN_ERR "ufs_change_blocknr: "
                               "can not read page: ino %lu, index: %lu\n",
                               mapping->host->i_ino, index);

                        page = ERR_PTR(-EIO);
                }
        }
out:
        return page;
}

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