1317 lines
32 KiB
C
1317 lines
32 KiB
C
/*
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* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
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* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
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*
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* This copyrighted material is made available to anyone wishing to use,
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* modify, copy, or redistribute it subject to the terms and conditions
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* of the GNU General Public License version 2.
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*/
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#include <linux/spinlock.h>
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#include <linux/completion.h>
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#include <linux/buffer_head.h>
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#include <linux/blkdev.h>
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#include <linux/gfs2_ondisk.h>
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#include <linux/crc32.h>
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#include "gfs2.h"
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#include "incore.h"
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#include "bmap.h"
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#include "glock.h"
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#include "inode.h"
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#include "meta_io.h"
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#include "quota.h"
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#include "rgrp.h"
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#include "super.h"
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#include "trans.h"
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#include "dir.h"
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#include "util.h"
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#include "trace_gfs2.h"
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/* This doesn't need to be that large as max 64 bit pointers in a 4k
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* block is 512, so __u16 is fine for that. It saves stack space to
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* keep it small.
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*/
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struct metapath {
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struct buffer_head *mp_bh[GFS2_MAX_META_HEIGHT];
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__u16 mp_list[GFS2_MAX_META_HEIGHT];
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};
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struct strip_mine {
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int sm_first;
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unsigned int sm_height;
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};
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/**
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* gfs2_unstuffer_page - unstuff a stuffed inode into a block cached by a page
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* @ip: the inode
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* @dibh: the dinode buffer
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* @block: the block number that was allocated
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* @page: The (optional) page. This is looked up if @page is NULL
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*
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* Returns: errno
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*/
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static int gfs2_unstuffer_page(struct gfs2_inode *ip, struct buffer_head *dibh,
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u64 block, struct page *page)
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{
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struct inode *inode = &ip->i_inode;
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struct buffer_head *bh;
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int release = 0;
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if (!page || page->index) {
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page = grab_cache_page(inode->i_mapping, 0);
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if (!page)
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return -ENOMEM;
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release = 1;
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}
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if (!PageUptodate(page)) {
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void *kaddr = kmap(page);
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u64 dsize = i_size_read(inode);
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if (dsize > (dibh->b_size - sizeof(struct gfs2_dinode)))
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dsize = dibh->b_size - sizeof(struct gfs2_dinode);
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memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize);
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memset(kaddr + dsize, 0, PAGE_CACHE_SIZE - dsize);
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kunmap(page);
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SetPageUptodate(page);
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}
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if (!page_has_buffers(page))
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create_empty_buffers(page, 1 << inode->i_blkbits,
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(1 << BH_Uptodate));
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bh = page_buffers(page);
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if (!buffer_mapped(bh))
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map_bh(bh, inode->i_sb, block);
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set_buffer_uptodate(bh);
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if (!gfs2_is_jdata(ip))
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mark_buffer_dirty(bh);
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if (!gfs2_is_writeback(ip))
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gfs2_trans_add_bh(ip->i_gl, bh, 0);
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if (release) {
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unlock_page(page);
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page_cache_release(page);
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}
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return 0;
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}
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/**
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* gfs2_unstuff_dinode - Unstuff a dinode when the data has grown too big
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* @ip: The GFS2 inode to unstuff
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* @page: The (optional) page. This is looked up if the @page is NULL
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*
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* This routine unstuffs a dinode and returns it to a "normal" state such
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* that the height can be grown in the traditional way.
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*
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* Returns: errno
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*/
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int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page)
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{
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struct buffer_head *bh, *dibh;
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struct gfs2_dinode *di;
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u64 block = 0;
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int isdir = gfs2_is_dir(ip);
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int error;
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down_write(&ip->i_rw_mutex);
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error = gfs2_meta_inode_buffer(ip, &dibh);
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if (error)
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goto out;
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if (i_size_read(&ip->i_inode)) {
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/* Get a free block, fill it with the stuffed data,
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and write it out to disk */
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unsigned int n = 1;
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error = gfs2_alloc_block(ip, &block, &n);
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if (error)
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goto out_brelse;
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if (isdir) {
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gfs2_trans_add_unrevoke(GFS2_SB(&ip->i_inode), block, 1);
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error = gfs2_dir_get_new_buffer(ip, block, &bh);
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if (error)
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goto out_brelse;
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gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_meta_header),
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dibh, sizeof(struct gfs2_dinode));
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brelse(bh);
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} else {
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error = gfs2_unstuffer_page(ip, dibh, block, page);
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if (error)
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goto out_brelse;
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}
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}
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/* Set up the pointer to the new block */
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gfs2_trans_add_bh(ip->i_gl, dibh, 1);
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di = (struct gfs2_dinode *)dibh->b_data;
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gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
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if (i_size_read(&ip->i_inode)) {
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*(__be64 *)(di + 1) = cpu_to_be64(block);
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gfs2_add_inode_blocks(&ip->i_inode, 1);
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di->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
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}
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ip->i_height = 1;
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di->di_height = cpu_to_be16(1);
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out_brelse:
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brelse(dibh);
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out:
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up_write(&ip->i_rw_mutex);
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return error;
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}
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/**
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* find_metapath - Find path through the metadata tree
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* @sdp: The superblock
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* @mp: The metapath to return the result in
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* @block: The disk block to look up
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* @height: The pre-calculated height of the metadata tree
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*
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* This routine returns a struct metapath structure that defines a path
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* through the metadata of inode "ip" to get to block "block".
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*
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* Example:
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* Given: "ip" is a height 3 file, "offset" is 101342453, and this is a
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* filesystem with a blocksize of 4096.
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*
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* find_metapath() would return a struct metapath structure set to:
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* mp_offset = 101342453, mp_height = 3, mp_list[0] = 0, mp_list[1] = 48,
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* and mp_list[2] = 165.
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*
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* That means that in order to get to the block containing the byte at
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* offset 101342453, we would load the indirect block pointed to by pointer
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* 0 in the dinode. We would then load the indirect block pointed to by
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* pointer 48 in that indirect block. We would then load the data block
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* pointed to by pointer 165 in that indirect block.
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*
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* ----------------------------------------
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* | Dinode | |
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* | | 4|
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* | |0 1 2 3 4 5 9|
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* | | 6|
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* ----------------------------------------
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* |
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* |
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* V
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* ----------------------------------------
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* | Indirect Block |
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* | 5|
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* | 4 4 4 4 4 5 5 1|
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* |0 5 6 7 8 9 0 1 2|
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* ----------------------------------------
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* |
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* |
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* V
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* ----------------------------------------
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* | Indirect Block |
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* | 1 1 1 1 1 5|
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* | 6 6 6 6 6 1|
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* |0 3 4 5 6 7 2|
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* ----------------------------------------
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* |
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* |
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* V
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* ----------------------------------------
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* | Data block containing offset |
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* | 101342453 |
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* | |
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* | |
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* ----------------------------------------
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*
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*/
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static void find_metapath(const struct gfs2_sbd *sdp, u64 block,
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struct metapath *mp, unsigned int height)
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{
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unsigned int i;
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for (i = height; i--;)
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mp->mp_list[i] = do_div(block, sdp->sd_inptrs);
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}
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static inline unsigned int metapath_branch_start(const struct metapath *mp)
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{
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if (mp->mp_list[0] == 0)
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return 2;
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return 1;
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}
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/**
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* metapointer - Return pointer to start of metadata in a buffer
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* @height: The metadata height (0 = dinode)
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* @mp: The metapath
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*
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* Return a pointer to the block number of the next height of the metadata
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* tree given a buffer containing the pointer to the current height of the
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* metadata tree.
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*/
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static inline __be64 *metapointer(unsigned int height, const struct metapath *mp)
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{
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struct buffer_head *bh = mp->mp_bh[height];
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unsigned int head_size = (height > 0) ?
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sizeof(struct gfs2_meta_header) : sizeof(struct gfs2_dinode);
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return ((__be64 *)(bh->b_data + head_size)) + mp->mp_list[height];
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}
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static void gfs2_metapath_ra(struct gfs2_glock *gl,
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const struct buffer_head *bh, const __be64 *pos)
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{
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struct buffer_head *rabh;
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const __be64 *endp = (const __be64 *)(bh->b_data + bh->b_size);
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const __be64 *t;
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for (t = pos; t < endp; t++) {
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if (!*t)
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continue;
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rabh = gfs2_getbuf(gl, be64_to_cpu(*t), CREATE);
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if (trylock_buffer(rabh)) {
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if (!buffer_uptodate(rabh)) {
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rabh->b_end_io = end_buffer_read_sync;
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submit_bh(READA | REQ_META, rabh);
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continue;
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}
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unlock_buffer(rabh);
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}
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brelse(rabh);
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}
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}
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/**
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* lookup_metapath - Walk the metadata tree to a specific point
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* @ip: The inode
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* @mp: The metapath
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*
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* Assumes that the inode's buffer has already been looked up and
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* hooked onto mp->mp_bh[0] and that the metapath has been initialised
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* by find_metapath().
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*
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* If this function encounters part of the tree which has not been
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* allocated, it returns the current height of the tree at the point
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* at which it found the unallocated block. Blocks which are found are
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* added to the mp->mp_bh[] list.
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*
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* Returns: error or height of metadata tree
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*/
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static int lookup_metapath(struct gfs2_inode *ip, struct metapath *mp)
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{
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unsigned int end_of_metadata = ip->i_height - 1;
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unsigned int x;
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__be64 *ptr;
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u64 dblock;
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int ret;
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for (x = 0; x < end_of_metadata; x++) {
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ptr = metapointer(x, mp);
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dblock = be64_to_cpu(*ptr);
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if (!dblock)
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return x + 1;
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ret = gfs2_meta_indirect_buffer(ip, x+1, dblock, 0, &mp->mp_bh[x+1]);
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if (ret)
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return ret;
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}
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return ip->i_height;
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}
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static inline void release_metapath(struct metapath *mp)
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{
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int i;
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for (i = 0; i < GFS2_MAX_META_HEIGHT; i++) {
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if (mp->mp_bh[i] == NULL)
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break;
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brelse(mp->mp_bh[i]);
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}
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}
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/**
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* gfs2_extent_length - Returns length of an extent of blocks
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* @start: Start of the buffer
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* @len: Length of the buffer in bytes
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* @ptr: Current position in the buffer
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* @limit: Max extent length to return (0 = unlimited)
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* @eob: Set to 1 if we hit "end of block"
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*
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* If the first block is zero (unallocated) it will return the number of
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* unallocated blocks in the extent, otherwise it will return the number
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* of contiguous blocks in the extent.
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*
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* Returns: The length of the extent (minimum of one block)
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*/
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static inline unsigned int gfs2_extent_length(void *start, unsigned int len, __be64 *ptr, unsigned limit, int *eob)
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{
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const __be64 *end = (start + len);
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const __be64 *first = ptr;
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u64 d = be64_to_cpu(*ptr);
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*eob = 0;
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do {
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ptr++;
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if (ptr >= end)
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break;
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if (limit && --limit == 0)
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break;
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if (d)
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d++;
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} while(be64_to_cpu(*ptr) == d);
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if (ptr >= end)
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*eob = 1;
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return (ptr - first);
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}
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static inline void bmap_lock(struct gfs2_inode *ip, int create)
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{
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if (create)
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down_write(&ip->i_rw_mutex);
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else
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down_read(&ip->i_rw_mutex);
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}
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static inline void bmap_unlock(struct gfs2_inode *ip, int create)
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{
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if (create)
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up_write(&ip->i_rw_mutex);
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else
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up_read(&ip->i_rw_mutex);
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}
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static inline __be64 *gfs2_indirect_init(struct metapath *mp,
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struct gfs2_glock *gl, unsigned int i,
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unsigned offset, u64 bn)
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{
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__be64 *ptr = (__be64 *)(mp->mp_bh[i - 1]->b_data +
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((i > 1) ? sizeof(struct gfs2_meta_header) :
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sizeof(struct gfs2_dinode)));
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BUG_ON(i < 1);
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BUG_ON(mp->mp_bh[i] != NULL);
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mp->mp_bh[i] = gfs2_meta_new(gl, bn);
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gfs2_trans_add_bh(gl, mp->mp_bh[i], 1);
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gfs2_metatype_set(mp->mp_bh[i], GFS2_METATYPE_IN, GFS2_FORMAT_IN);
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gfs2_buffer_clear_tail(mp->mp_bh[i], sizeof(struct gfs2_meta_header));
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ptr += offset;
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*ptr = cpu_to_be64(bn);
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return ptr;
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}
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enum alloc_state {
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ALLOC_DATA = 0,
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ALLOC_GROW_DEPTH = 1,
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ALLOC_GROW_HEIGHT = 2,
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/* ALLOC_UNSTUFF = 3, TBD and rather complicated */
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};
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/**
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* gfs2_bmap_alloc - Build a metadata tree of the requested height
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* @inode: The GFS2 inode
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* @lblock: The logical starting block of the extent
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* @bh_map: This is used to return the mapping details
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* @mp: The metapath
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* @sheight: The starting height (i.e. whats already mapped)
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* @height: The height to build to
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* @maxlen: The max number of data blocks to alloc
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*
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* In this routine we may have to alloc:
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* i) Indirect blocks to grow the metadata tree height
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* ii) Indirect blocks to fill in lower part of the metadata tree
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* iii) Data blocks
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*
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* The function is in two parts. The first part works out the total
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* number of blocks which we need. The second part does the actual
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* allocation asking for an extent at a time (if enough contiguous free
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* blocks are available, there will only be one request per bmap call)
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* and uses the state machine to initialise the blocks in order.
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*
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* Returns: errno on error
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*/
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static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock,
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struct buffer_head *bh_map, struct metapath *mp,
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const unsigned int sheight,
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const unsigned int height,
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const unsigned int maxlen)
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{
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struct gfs2_inode *ip = GFS2_I(inode);
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struct gfs2_sbd *sdp = GFS2_SB(inode);
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struct super_block *sb = sdp->sd_vfs;
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struct buffer_head *dibh = mp->mp_bh[0];
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u64 bn, dblock = 0;
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unsigned n, i, blks, alloced = 0, iblks = 0, branch_start = 0;
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unsigned dblks = 0;
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unsigned ptrs_per_blk;
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const unsigned end_of_metadata = height - 1;
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int ret;
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int eob = 0;
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enum alloc_state state;
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__be64 *ptr;
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__be64 zero_bn = 0;
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|
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BUG_ON(sheight < 1);
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BUG_ON(dibh == NULL);
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|
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gfs2_trans_add_bh(ip->i_gl, dibh, 1);
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|
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if (height == sheight) {
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struct buffer_head *bh;
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/* Bottom indirect block exists, find unalloced extent size */
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ptr = metapointer(end_of_metadata, mp);
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bh = mp->mp_bh[end_of_metadata];
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dblks = gfs2_extent_length(bh->b_data, bh->b_size, ptr, maxlen,
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&eob);
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BUG_ON(dblks < 1);
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state = ALLOC_DATA;
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} else {
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/* Need to allocate indirect blocks */
|
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ptrs_per_blk = height > 1 ? sdp->sd_inptrs : sdp->sd_diptrs;
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dblks = min(maxlen, ptrs_per_blk - mp->mp_list[end_of_metadata]);
|
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if (height == ip->i_height) {
|
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/* Writing into existing tree, extend tree down */
|
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iblks = height - sheight;
|
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state = ALLOC_GROW_DEPTH;
|
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} else {
|
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/* Building up tree height */
|
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state = ALLOC_GROW_HEIGHT;
|
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iblks = height - ip->i_height;
|
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branch_start = metapath_branch_start(mp);
|
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iblks += (height - branch_start);
|
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}
|
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}
|
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|
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/* start of the second part of the function (state machine) */
|
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|
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blks = dblks + iblks;
|
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i = sheight;
|
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do {
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int error;
|
|
n = blks - alloced;
|
|
error = gfs2_alloc_block(ip, &bn, &n);
|
|
if (error)
|
|
return error;
|
|
alloced += n;
|
|
if (state != ALLOC_DATA || gfs2_is_jdata(ip))
|
|
gfs2_trans_add_unrevoke(sdp, bn, n);
|
|
switch (state) {
|
|
/* Growing height of tree */
|
|
case ALLOC_GROW_HEIGHT:
|
|
if (i == 1) {
|
|
ptr = (__be64 *)(dibh->b_data +
|
|
sizeof(struct gfs2_dinode));
|
|
zero_bn = *ptr;
|
|
}
|
|
for (; i - 1 < height - ip->i_height && n > 0; i++, n--)
|
|
gfs2_indirect_init(mp, ip->i_gl, i, 0, bn++);
|
|
if (i - 1 == height - ip->i_height) {
|
|
i--;
|
|
gfs2_buffer_copy_tail(mp->mp_bh[i],
|
|
sizeof(struct gfs2_meta_header),
|
|
dibh, sizeof(struct gfs2_dinode));
|
|
gfs2_buffer_clear_tail(dibh,
|
|
sizeof(struct gfs2_dinode) +
|
|
sizeof(__be64));
|
|
ptr = (__be64 *)(mp->mp_bh[i]->b_data +
|
|
sizeof(struct gfs2_meta_header));
|
|
*ptr = zero_bn;
|
|
state = ALLOC_GROW_DEPTH;
|
|
for(i = branch_start; i < height; i++) {
|
|
if (mp->mp_bh[i] == NULL)
|
|
break;
|
|
brelse(mp->mp_bh[i]);
|
|
mp->mp_bh[i] = NULL;
|
|
}
|
|
i = branch_start;
|
|
}
|
|
if (n == 0)
|
|
break;
|
|
/* Branching from existing tree */
|
|
case ALLOC_GROW_DEPTH:
|
|
if (i > 1 && i < height)
|
|
gfs2_trans_add_bh(ip->i_gl, mp->mp_bh[i-1], 1);
|
|
for (; i < height && n > 0; i++, n--)
|
|
gfs2_indirect_init(mp, ip->i_gl, i,
|
|
mp->mp_list[i-1], bn++);
|
|
if (i == height)
|
|
state = ALLOC_DATA;
|
|
if (n == 0)
|
|
break;
|
|
/* Tree complete, adding data blocks */
|
|
case ALLOC_DATA:
|
|
BUG_ON(n > dblks);
|
|
BUG_ON(mp->mp_bh[end_of_metadata] == NULL);
|
|
gfs2_trans_add_bh(ip->i_gl, mp->mp_bh[end_of_metadata], 1);
|
|
dblks = n;
|
|
ptr = metapointer(end_of_metadata, mp);
|
|
dblock = bn;
|
|
while (n-- > 0)
|
|
*ptr++ = cpu_to_be64(bn++);
|
|
if (buffer_zeronew(bh_map)) {
|
|
ret = sb_issue_zeroout(sb, dblock, dblks,
|
|
GFP_NOFS);
|
|
if (ret) {
|
|
fs_err(sdp,
|
|
"Failed to zero data buffers\n");
|
|
clear_buffer_zeronew(bh_map);
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
} while ((state != ALLOC_DATA) || !dblock);
|
|
|
|
ip->i_height = height;
|
|
gfs2_add_inode_blocks(&ip->i_inode, alloced);
|
|
gfs2_dinode_out(ip, mp->mp_bh[0]->b_data);
|
|
map_bh(bh_map, inode->i_sb, dblock);
|
|
bh_map->b_size = dblks << inode->i_blkbits;
|
|
set_buffer_new(bh_map);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* gfs2_block_map - Map a block from an inode to a disk block
|
|
* @inode: The inode
|
|
* @lblock: The logical block number
|
|
* @bh_map: The bh to be mapped
|
|
* @create: True if its ok to alloc blocks to satify the request
|
|
*
|
|
* Sets buffer_mapped() if successful, sets buffer_boundary() if a
|
|
* read of metadata will be required before the next block can be
|
|
* mapped. Sets buffer_new() if new blocks were allocated.
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
int gfs2_block_map(struct inode *inode, sector_t lblock,
|
|
struct buffer_head *bh_map, int create)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
struct gfs2_sbd *sdp = GFS2_SB(inode);
|
|
unsigned int bsize = sdp->sd_sb.sb_bsize;
|
|
const unsigned int maxlen = bh_map->b_size >> inode->i_blkbits;
|
|
const u64 *arr = sdp->sd_heightsize;
|
|
__be64 *ptr;
|
|
u64 size;
|
|
struct metapath mp;
|
|
int ret;
|
|
int eob;
|
|
unsigned int len;
|
|
struct buffer_head *bh;
|
|
u8 height;
|
|
|
|
BUG_ON(maxlen == 0);
|
|
|
|
memset(mp.mp_bh, 0, sizeof(mp.mp_bh));
|
|
bmap_lock(ip, create);
|
|
clear_buffer_mapped(bh_map);
|
|
clear_buffer_new(bh_map);
|
|
clear_buffer_boundary(bh_map);
|
|
trace_gfs2_bmap(ip, bh_map, lblock, create, 1);
|
|
if (gfs2_is_dir(ip)) {
|
|
bsize = sdp->sd_jbsize;
|
|
arr = sdp->sd_jheightsize;
|
|
}
|
|
|
|
ret = gfs2_meta_inode_buffer(ip, &mp.mp_bh[0]);
|
|
if (ret)
|
|
goto out;
|
|
|
|
height = ip->i_height;
|
|
size = (lblock + 1) * bsize;
|
|
while (size > arr[height])
|
|
height++;
|
|
find_metapath(sdp, lblock, &mp, height);
|
|
ret = 1;
|
|
if (height > ip->i_height || gfs2_is_stuffed(ip))
|
|
goto do_alloc;
|
|
ret = lookup_metapath(ip, &mp);
|
|
if (ret < 0)
|
|
goto out;
|
|
if (ret != ip->i_height)
|
|
goto do_alloc;
|
|
ptr = metapointer(ip->i_height - 1, &mp);
|
|
if (*ptr == 0)
|
|
goto do_alloc;
|
|
map_bh(bh_map, inode->i_sb, be64_to_cpu(*ptr));
|
|
bh = mp.mp_bh[ip->i_height - 1];
|
|
len = gfs2_extent_length(bh->b_data, bh->b_size, ptr, maxlen, &eob);
|
|
bh_map->b_size = (len << inode->i_blkbits);
|
|
if (eob)
|
|
set_buffer_boundary(bh_map);
|
|
ret = 0;
|
|
out:
|
|
release_metapath(&mp);
|
|
trace_gfs2_bmap(ip, bh_map, lblock, create, ret);
|
|
bmap_unlock(ip, create);
|
|
return ret;
|
|
|
|
do_alloc:
|
|
/* All allocations are done here, firstly check create flag */
|
|
if (!create) {
|
|
BUG_ON(gfs2_is_stuffed(ip));
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
|
|
/* At this point ret is the tree depth of already allocated blocks */
|
|
ret = gfs2_bmap_alloc(inode, lblock, bh_map, &mp, ret, height, maxlen);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Deprecated: do not use in new code
|
|
*/
|
|
int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen)
|
|
{
|
|
struct buffer_head bh = { .b_state = 0, .b_blocknr = 0 };
|
|
int ret;
|
|
int create = *new;
|
|
|
|
BUG_ON(!extlen);
|
|
BUG_ON(!dblock);
|
|
BUG_ON(!new);
|
|
|
|
bh.b_size = 1 << (inode->i_blkbits + (create ? 0 : 5));
|
|
ret = gfs2_block_map(inode, lblock, &bh, create);
|
|
*extlen = bh.b_size >> inode->i_blkbits;
|
|
*dblock = bh.b_blocknr;
|
|
if (buffer_new(&bh))
|
|
*new = 1;
|
|
else
|
|
*new = 0;
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* do_strip - Look for a layer a particular layer of the file and strip it off
|
|
* @ip: the inode
|
|
* @dibh: the dinode buffer
|
|
* @bh: A buffer of pointers
|
|
* @top: The first pointer in the buffer
|
|
* @bottom: One more than the last pointer
|
|
* @height: the height this buffer is at
|
|
* @data: a pointer to a struct strip_mine
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
static int do_strip(struct gfs2_inode *ip, struct buffer_head *dibh,
|
|
struct buffer_head *bh, __be64 *top, __be64 *bottom,
|
|
unsigned int height, struct strip_mine *sm)
|
|
{
|
|
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
|
|
struct gfs2_rgrp_list rlist;
|
|
u64 bn, bstart;
|
|
u32 blen, btotal;
|
|
__be64 *p;
|
|
unsigned int rg_blocks = 0;
|
|
int metadata;
|
|
unsigned int revokes = 0;
|
|
int x;
|
|
int error = 0;
|
|
|
|
if (!*top)
|
|
sm->sm_first = 0;
|
|
|
|
if (height != sm->sm_height)
|
|
return 0;
|
|
|
|
if (sm->sm_first) {
|
|
top++;
|
|
sm->sm_first = 0;
|
|
}
|
|
|
|
metadata = (height != ip->i_height - 1);
|
|
if (metadata)
|
|
revokes = (height) ? sdp->sd_inptrs : sdp->sd_diptrs;
|
|
else if (ip->i_depth)
|
|
revokes = sdp->sd_inptrs;
|
|
|
|
if (error)
|
|
return error;
|
|
|
|
memset(&rlist, 0, sizeof(struct gfs2_rgrp_list));
|
|
bstart = 0;
|
|
blen = 0;
|
|
|
|
for (p = top; p < bottom; p++) {
|
|
if (!*p)
|
|
continue;
|
|
|
|
bn = be64_to_cpu(*p);
|
|
|
|
if (bstart + blen == bn)
|
|
blen++;
|
|
else {
|
|
if (bstart)
|
|
gfs2_rlist_add(ip, &rlist, bstart);
|
|
|
|
bstart = bn;
|
|
blen = 1;
|
|
}
|
|
}
|
|
|
|
if (bstart)
|
|
gfs2_rlist_add(ip, &rlist, bstart);
|
|
else
|
|
goto out; /* Nothing to do */
|
|
|
|
gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE);
|
|
|
|
for (x = 0; x < rlist.rl_rgrps; x++) {
|
|
struct gfs2_rgrpd *rgd;
|
|
rgd = rlist.rl_ghs[x].gh_gl->gl_object;
|
|
rg_blocks += rgd->rd_length;
|
|
}
|
|
|
|
error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs);
|
|
if (error)
|
|
goto out_rlist;
|
|
|
|
error = gfs2_trans_begin(sdp, rg_blocks + RES_DINODE +
|
|
RES_INDIRECT + RES_STATFS + RES_QUOTA,
|
|
revokes);
|
|
if (error)
|
|
goto out_rg_gunlock;
|
|
|
|
down_write(&ip->i_rw_mutex);
|
|
|
|
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
|
|
gfs2_trans_add_bh(ip->i_gl, bh, 1);
|
|
|
|
bstart = 0;
|
|
blen = 0;
|
|
btotal = 0;
|
|
|
|
for (p = top; p < bottom; p++) {
|
|
if (!*p)
|
|
continue;
|
|
|
|
bn = be64_to_cpu(*p);
|
|
|
|
if (bstart + blen == bn)
|
|
blen++;
|
|
else {
|
|
if (bstart) {
|
|
__gfs2_free_blocks(ip, bstart, blen, metadata);
|
|
btotal += blen;
|
|
}
|
|
|
|
bstart = bn;
|
|
blen = 1;
|
|
}
|
|
|
|
*p = 0;
|
|
gfs2_add_inode_blocks(&ip->i_inode, -1);
|
|
}
|
|
if (bstart) {
|
|
__gfs2_free_blocks(ip, bstart, blen, metadata);
|
|
btotal += blen;
|
|
}
|
|
|
|
gfs2_statfs_change(sdp, 0, +btotal, 0);
|
|
gfs2_quota_change(ip, -(s64)btotal, ip->i_inode.i_uid,
|
|
ip->i_inode.i_gid);
|
|
|
|
ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
|
|
|
|
gfs2_dinode_out(ip, dibh->b_data);
|
|
|
|
up_write(&ip->i_rw_mutex);
|
|
|
|
gfs2_trans_end(sdp);
|
|
|
|
out_rg_gunlock:
|
|
gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs);
|
|
out_rlist:
|
|
gfs2_rlist_free(&rlist);
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* recursive_scan - recursively scan through the end of a file
|
|
* @ip: the inode
|
|
* @dibh: the dinode buffer
|
|
* @mp: the path through the metadata to the point to start
|
|
* @height: the height the recursion is at
|
|
* @block: the indirect block to look at
|
|
* @first: 1 if this is the first block
|
|
* @sm: data opaque to this function to pass to @bc
|
|
*
|
|
* When this is first called @height and @block should be zero and
|
|
* @first should be 1.
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
static int recursive_scan(struct gfs2_inode *ip, struct buffer_head *dibh,
|
|
struct metapath *mp, unsigned int height,
|
|
u64 block, int first, struct strip_mine *sm)
|
|
{
|
|
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
|
|
struct buffer_head *bh = NULL;
|
|
__be64 *top, *bottom;
|
|
u64 bn;
|
|
int error;
|
|
int mh_size = sizeof(struct gfs2_meta_header);
|
|
|
|
if (!height) {
|
|
error = gfs2_meta_inode_buffer(ip, &bh);
|
|
if (error)
|
|
return error;
|
|
dibh = bh;
|
|
|
|
top = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + mp->mp_list[0];
|
|
bottom = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + sdp->sd_diptrs;
|
|
} else {
|
|
error = gfs2_meta_indirect_buffer(ip, height, block, 0, &bh);
|
|
if (error)
|
|
return error;
|
|
|
|
top = (__be64 *)(bh->b_data + mh_size) +
|
|
(first ? mp->mp_list[height] : 0);
|
|
|
|
bottom = (__be64 *)(bh->b_data + mh_size) + sdp->sd_inptrs;
|
|
}
|
|
|
|
error = do_strip(ip, dibh, bh, top, bottom, height, sm);
|
|
if (error)
|
|
goto out;
|
|
|
|
if (height < ip->i_height - 1) {
|
|
|
|
gfs2_metapath_ra(ip->i_gl, bh, top);
|
|
|
|
for (; top < bottom; top++, first = 0) {
|
|
if (!*top)
|
|
continue;
|
|
|
|
bn = be64_to_cpu(*top);
|
|
|
|
error = recursive_scan(ip, dibh, mp, height + 1, bn,
|
|
first, sm);
|
|
if (error)
|
|
break;
|
|
}
|
|
}
|
|
out:
|
|
brelse(bh);
|
|
return error;
|
|
}
|
|
|
|
|
|
/**
|
|
* gfs2_block_truncate_page - Deal with zeroing out data for truncate
|
|
*
|
|
* This is partly borrowed from ext3.
|
|
*/
|
|
static int gfs2_block_truncate_page(struct address_space *mapping, loff_t from)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
unsigned long index = from >> PAGE_CACHE_SHIFT;
|
|
unsigned offset = from & (PAGE_CACHE_SIZE-1);
|
|
unsigned blocksize, iblock, length, pos;
|
|
struct buffer_head *bh;
|
|
struct page *page;
|
|
int err;
|
|
|
|
page = grab_cache_page(mapping, index);
|
|
if (!page)
|
|
return 0;
|
|
|
|
blocksize = inode->i_sb->s_blocksize;
|
|
length = blocksize - (offset & (blocksize - 1));
|
|
iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
|
|
|
|
if (!page_has_buffers(page))
|
|
create_empty_buffers(page, blocksize, 0);
|
|
|
|
/* Find the buffer that contains "offset" */
|
|
bh = page_buffers(page);
|
|
pos = blocksize;
|
|
while (offset >= pos) {
|
|
bh = bh->b_this_page;
|
|
iblock++;
|
|
pos += blocksize;
|
|
}
|
|
|
|
err = 0;
|
|
|
|
if (!buffer_mapped(bh)) {
|
|
gfs2_block_map(inode, iblock, bh, 0);
|
|
/* unmapped? It's a hole - nothing to do */
|
|
if (!buffer_mapped(bh))
|
|
goto unlock;
|
|
}
|
|
|
|
/* Ok, it's mapped. Make sure it's up-to-date */
|
|
if (PageUptodate(page))
|
|
set_buffer_uptodate(bh);
|
|
|
|
if (!buffer_uptodate(bh)) {
|
|
err = -EIO;
|
|
ll_rw_block(READ, 1, &bh);
|
|
wait_on_buffer(bh);
|
|
/* Uhhuh. Read error. Complain and punt. */
|
|
if (!buffer_uptodate(bh))
|
|
goto unlock;
|
|
err = 0;
|
|
}
|
|
|
|
if (!gfs2_is_writeback(ip))
|
|
gfs2_trans_add_bh(ip->i_gl, bh, 0);
|
|
|
|
zero_user(page, offset, length);
|
|
mark_buffer_dirty(bh);
|
|
unlock:
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
return err;
|
|
}
|
|
|
|
static int trunc_start(struct inode *inode, u64 oldsize, u64 newsize)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
struct gfs2_sbd *sdp = GFS2_SB(inode);
|
|
struct address_space *mapping = inode->i_mapping;
|
|
struct buffer_head *dibh;
|
|
int journaled = gfs2_is_jdata(ip);
|
|
int error;
|
|
|
|
error = gfs2_trans_begin(sdp,
|
|
RES_DINODE + (journaled ? RES_JDATA : 0), 0);
|
|
if (error)
|
|
return error;
|
|
|
|
error = gfs2_meta_inode_buffer(ip, &dibh);
|
|
if (error)
|
|
goto out;
|
|
|
|
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
|
|
|
|
if (gfs2_is_stuffed(ip)) {
|
|
gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode) + newsize);
|
|
} else {
|
|
if (newsize & (u64)(sdp->sd_sb.sb_bsize - 1)) {
|
|
error = gfs2_block_truncate_page(mapping, newsize);
|
|
if (error)
|
|
goto out_brelse;
|
|
}
|
|
ip->i_diskflags |= GFS2_DIF_TRUNC_IN_PROG;
|
|
}
|
|
|
|
i_size_write(inode, newsize);
|
|
ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
|
|
gfs2_dinode_out(ip, dibh->b_data);
|
|
|
|
truncate_pagecache(inode, oldsize, newsize);
|
|
out_brelse:
|
|
brelse(dibh);
|
|
out:
|
|
gfs2_trans_end(sdp);
|
|
return error;
|
|
}
|
|
|
|
static int trunc_dealloc(struct gfs2_inode *ip, u64 size)
|
|
{
|
|
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
|
|
unsigned int height = ip->i_height;
|
|
u64 lblock;
|
|
struct metapath mp;
|
|
int error;
|
|
|
|
if (!size)
|
|
lblock = 0;
|
|
else
|
|
lblock = (size - 1) >> sdp->sd_sb.sb_bsize_shift;
|
|
|
|
find_metapath(sdp, lblock, &mp, ip->i_height);
|
|
if (!gfs2_alloc_get(ip))
|
|
return -ENOMEM;
|
|
|
|
error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
|
|
if (error)
|
|
goto out;
|
|
|
|
while (height--) {
|
|
struct strip_mine sm;
|
|
sm.sm_first = !!size;
|
|
sm.sm_height = height;
|
|
|
|
error = recursive_scan(ip, NULL, &mp, 0, 0, 1, &sm);
|
|
if (error)
|
|
break;
|
|
}
|
|
|
|
gfs2_quota_unhold(ip);
|
|
|
|
out:
|
|
gfs2_alloc_put(ip);
|
|
return error;
|
|
}
|
|
|
|
static int trunc_end(struct gfs2_inode *ip)
|
|
{
|
|
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
|
|
struct buffer_head *dibh;
|
|
int error;
|
|
|
|
error = gfs2_trans_begin(sdp, RES_DINODE, 0);
|
|
if (error)
|
|
return error;
|
|
|
|
down_write(&ip->i_rw_mutex);
|
|
|
|
error = gfs2_meta_inode_buffer(ip, &dibh);
|
|
if (error)
|
|
goto out;
|
|
|
|
if (!i_size_read(&ip->i_inode)) {
|
|
ip->i_height = 0;
|
|
ip->i_goal = ip->i_no_addr;
|
|
gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
|
|
}
|
|
ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
|
|
ip->i_diskflags &= ~GFS2_DIF_TRUNC_IN_PROG;
|
|
|
|
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
|
|
gfs2_dinode_out(ip, dibh->b_data);
|
|
brelse(dibh);
|
|
|
|
out:
|
|
up_write(&ip->i_rw_mutex);
|
|
gfs2_trans_end(sdp);
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* do_shrink - make a file smaller
|
|
* @inode: the inode
|
|
* @oldsize: the current inode size
|
|
* @newsize: the size to make the file
|
|
*
|
|
* Called with an exclusive lock on @inode. The @size must
|
|
* be equal to or smaller than the current inode size.
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
static int do_shrink(struct inode *inode, u64 oldsize, u64 newsize)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
int error;
|
|
|
|
error = trunc_start(inode, oldsize, newsize);
|
|
if (error < 0)
|
|
return error;
|
|
if (gfs2_is_stuffed(ip))
|
|
return 0;
|
|
|
|
error = trunc_dealloc(ip, newsize);
|
|
if (error == 0)
|
|
error = trunc_end(ip);
|
|
|
|
return error;
|
|
}
|
|
|
|
void gfs2_trim_blocks(struct inode *inode)
|
|
{
|
|
u64 size = inode->i_size;
|
|
int ret;
|
|
|
|
ret = do_shrink(inode, size, size);
|
|
WARN_ON(ret != 0);
|
|
}
|
|
|
|
/**
|
|
* do_grow - Touch and update inode size
|
|
* @inode: The inode
|
|
* @size: The new size
|
|
*
|
|
* This function updates the timestamps on the inode and
|
|
* may also increase the size of the inode. This function
|
|
* must not be called with @size any smaller than the current
|
|
* inode size.
|
|
*
|
|
* Although it is not strictly required to unstuff files here,
|
|
* earlier versions of GFS2 have a bug in the stuffed file reading
|
|
* code which will result in a buffer overrun if the size is larger
|
|
* than the max stuffed file size. In order to prevent this from
|
|
* occurring, such files are unstuffed, but in other cases we can
|
|
* just update the inode size directly.
|
|
*
|
|
* Returns: 0 on success, or -ve on error
|
|
*/
|
|
|
|
static int do_grow(struct inode *inode, u64 size)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
struct gfs2_sbd *sdp = GFS2_SB(inode);
|
|
struct buffer_head *dibh;
|
|
struct gfs2_alloc *al = NULL;
|
|
int error;
|
|
|
|
if (gfs2_is_stuffed(ip) &&
|
|
(size > (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)))) {
|
|
al = gfs2_alloc_get(ip);
|
|
if (al == NULL)
|
|
return -ENOMEM;
|
|
|
|
error = gfs2_quota_lock_check(ip);
|
|
if (error)
|
|
goto do_grow_alloc_put;
|
|
|
|
al->al_requested = 1;
|
|
error = gfs2_inplace_reserve(ip);
|
|
if (error)
|
|
goto do_grow_qunlock;
|
|
}
|
|
|
|
error = gfs2_trans_begin(sdp, RES_DINODE + RES_STATFS + RES_RG_BIT, 0);
|
|
if (error)
|
|
goto do_grow_release;
|
|
|
|
if (al) {
|
|
error = gfs2_unstuff_dinode(ip, NULL);
|
|
if (error)
|
|
goto do_end_trans;
|
|
}
|
|
|
|
error = gfs2_meta_inode_buffer(ip, &dibh);
|
|
if (error)
|
|
goto do_end_trans;
|
|
|
|
i_size_write(inode, size);
|
|
ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
|
|
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
|
|
gfs2_dinode_out(ip, dibh->b_data);
|
|
brelse(dibh);
|
|
|
|
do_end_trans:
|
|
gfs2_trans_end(sdp);
|
|
do_grow_release:
|
|
if (al) {
|
|
gfs2_inplace_release(ip);
|
|
do_grow_qunlock:
|
|
gfs2_quota_unlock(ip);
|
|
do_grow_alloc_put:
|
|
gfs2_alloc_put(ip);
|
|
}
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* gfs2_setattr_size - make a file a given size
|
|
* @inode: the inode
|
|
* @newsize: the size to make the file
|
|
*
|
|
* The file size can grow, shrink, or stay the same size. This
|
|
* is called holding i_mutex and an exclusive glock on the inode
|
|
* in question.
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
int gfs2_setattr_size(struct inode *inode, u64 newsize)
|
|
{
|
|
int ret;
|
|
u64 oldsize;
|
|
|
|
BUG_ON(!S_ISREG(inode->i_mode));
|
|
|
|
ret = inode_newsize_ok(inode, newsize);
|
|
if (ret)
|
|
return ret;
|
|
|
|
inode_dio_wait(inode);
|
|
|
|
oldsize = inode->i_size;
|
|
if (newsize >= oldsize)
|
|
return do_grow(inode, newsize);
|
|
|
|
return do_shrink(inode, oldsize, newsize);
|
|
}
|
|
|
|
int gfs2_truncatei_resume(struct gfs2_inode *ip)
|
|
{
|
|
int error;
|
|
error = trunc_dealloc(ip, i_size_read(&ip->i_inode));
|
|
if (!error)
|
|
error = trunc_end(ip);
|
|
return error;
|
|
}
|
|
|
|
int gfs2_file_dealloc(struct gfs2_inode *ip)
|
|
{
|
|
return trunc_dealloc(ip, 0);
|
|
}
|
|
|
|
/**
|
|
* gfs2_write_alloc_required - figure out if a write will require an allocation
|
|
* @ip: the file being written to
|
|
* @offset: the offset to write to
|
|
* @len: the number of bytes being written
|
|
*
|
|
* Returns: 1 if an alloc is required, 0 otherwise
|
|
*/
|
|
|
|
int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset,
|
|
unsigned int len)
|
|
{
|
|
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
|
|
struct buffer_head bh;
|
|
unsigned int shift;
|
|
u64 lblock, lblock_stop, size;
|
|
u64 end_of_file;
|
|
|
|
if (!len)
|
|
return 0;
|
|
|
|
if (gfs2_is_stuffed(ip)) {
|
|
if (offset + len >
|
|
sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
shift = sdp->sd_sb.sb_bsize_shift;
|
|
BUG_ON(gfs2_is_dir(ip));
|
|
end_of_file = (i_size_read(&ip->i_inode) + sdp->sd_sb.sb_bsize - 1) >> shift;
|
|
lblock = offset >> shift;
|
|
lblock_stop = (offset + len + sdp->sd_sb.sb_bsize - 1) >> shift;
|
|
if (lblock_stop > end_of_file)
|
|
return 1;
|
|
|
|
size = (lblock_stop - lblock) << shift;
|
|
do {
|
|
bh.b_state = 0;
|
|
bh.b_size = size;
|
|
gfs2_block_map(&ip->i_inode, lblock, &bh, 0);
|
|
if (!buffer_mapped(&bh))
|
|
return 1;
|
|
size -= bh.b_size;
|
|
lblock += (bh.b_size >> ip->i_inode.i_blkbits);
|
|
} while(size > 0);
|
|
|
|
return 0;
|
|
}
|
|
|