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![Wang Shilong](/assets/img/avatar_default.png)
Add a necessary check when an io error happens. If io error happens,free the memory allocated and forget buffer head. Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com> Signed-off-by: Jan Kara <jack@suse.cz>
1568 lines
45 KiB
C
1568 lines
45 KiB
C
/*
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* linux/fs/ext2/inode.c
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*
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* Copyright (C) 1992, 1993, 1994, 1995
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* Remy Card (card@masi.ibp.fr)
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* Laboratoire MASI - Institut Blaise Pascal
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* Universite Pierre et Marie Curie (Paris VI)
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*
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* from
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*
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* linux/fs/minix/inode.c
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*
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* Goal-directed block allocation by Stephen Tweedie
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* (sct@dcs.ed.ac.uk), 1993, 1998
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* Big-endian to little-endian byte-swapping/bitmaps by
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* David S. Miller (davem@caip.rutgers.edu), 1995
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* 64-bit file support on 64-bit platforms by Jakub Jelinek
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* (jj@sunsite.ms.mff.cuni.cz)
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*
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* Assorted race fixes, rewrite of ext2_get_block() by Al Viro, 2000
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*/
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#include <linux/time.h>
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#include <linux/highuid.h>
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#include <linux/pagemap.h>
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#include <linux/quotaops.h>
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#include <linux/writeback.h>
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#include <linux/buffer_head.h>
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#include <linux/mpage.h>
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#include <linux/fiemap.h>
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#include <linux/namei.h>
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#include "ext2.h"
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#include "acl.h"
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#include "xip.h"
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static int __ext2_write_inode(struct inode *inode, int do_sync);
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/*
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* Test whether an inode is a fast symlink.
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*/
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static inline int ext2_inode_is_fast_symlink(struct inode *inode)
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{
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int ea_blocks = EXT2_I(inode)->i_file_acl ?
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(inode->i_sb->s_blocksize >> 9) : 0;
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return (S_ISLNK(inode->i_mode) &&
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inode->i_blocks - ea_blocks == 0);
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}
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static void ext2_truncate_blocks(struct inode *inode, loff_t offset);
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static void ext2_write_failed(struct address_space *mapping, loff_t to)
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{
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struct inode *inode = mapping->host;
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if (to > inode->i_size) {
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truncate_pagecache(inode, to, inode->i_size);
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ext2_truncate_blocks(inode, inode->i_size);
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}
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}
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/*
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* Called at the last iput() if i_nlink is zero.
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*/
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void ext2_evict_inode(struct inode * inode)
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{
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struct ext2_block_alloc_info *rsv;
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int want_delete = 0;
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if (!inode->i_nlink && !is_bad_inode(inode)) {
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want_delete = 1;
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dquot_initialize(inode);
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} else {
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dquot_drop(inode);
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}
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truncate_inode_pages(&inode->i_data, 0);
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if (want_delete) {
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sb_start_intwrite(inode->i_sb);
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/* set dtime */
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EXT2_I(inode)->i_dtime = get_seconds();
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mark_inode_dirty(inode);
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__ext2_write_inode(inode, inode_needs_sync(inode));
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/* truncate to 0 */
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inode->i_size = 0;
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if (inode->i_blocks)
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ext2_truncate_blocks(inode, 0);
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}
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invalidate_inode_buffers(inode);
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clear_inode(inode);
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ext2_discard_reservation(inode);
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rsv = EXT2_I(inode)->i_block_alloc_info;
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EXT2_I(inode)->i_block_alloc_info = NULL;
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if (unlikely(rsv))
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kfree(rsv);
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if (want_delete) {
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ext2_free_inode(inode);
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sb_end_intwrite(inode->i_sb);
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}
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}
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typedef struct {
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__le32 *p;
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__le32 key;
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struct buffer_head *bh;
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} Indirect;
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static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v)
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{
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p->key = *(p->p = v);
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p->bh = bh;
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}
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static inline int verify_chain(Indirect *from, Indirect *to)
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{
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while (from <= to && from->key == *from->p)
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from++;
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return (from > to);
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}
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/**
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* ext2_block_to_path - parse the block number into array of offsets
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* @inode: inode in question (we are only interested in its superblock)
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* @i_block: block number to be parsed
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* @offsets: array to store the offsets in
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* @boundary: set this non-zero if the referred-to block is likely to be
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* followed (on disk) by an indirect block.
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* To store the locations of file's data ext2 uses a data structure common
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* for UNIX filesystems - tree of pointers anchored in the inode, with
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* data blocks at leaves and indirect blocks in intermediate nodes.
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* This function translates the block number into path in that tree -
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* return value is the path length and @offsets[n] is the offset of
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* pointer to (n+1)th node in the nth one. If @block is out of range
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* (negative or too large) warning is printed and zero returned.
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*
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* Note: function doesn't find node addresses, so no IO is needed. All
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* we need to know is the capacity of indirect blocks (taken from the
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* inode->i_sb).
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*/
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/*
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* Portability note: the last comparison (check that we fit into triple
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* indirect block) is spelled differently, because otherwise on an
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* architecture with 32-bit longs and 8Kb pages we might get into trouble
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* if our filesystem had 8Kb blocks. We might use long long, but that would
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* kill us on x86. Oh, well, at least the sign propagation does not matter -
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* i_block would have to be negative in the very beginning, so we would not
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* get there at all.
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*/
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static int ext2_block_to_path(struct inode *inode,
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long i_block, int offsets[4], int *boundary)
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{
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int ptrs = EXT2_ADDR_PER_BLOCK(inode->i_sb);
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int ptrs_bits = EXT2_ADDR_PER_BLOCK_BITS(inode->i_sb);
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const long direct_blocks = EXT2_NDIR_BLOCKS,
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indirect_blocks = ptrs,
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double_blocks = (1 << (ptrs_bits * 2));
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int n = 0;
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int final = 0;
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if (i_block < 0) {
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ext2_msg(inode->i_sb, KERN_WARNING,
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"warning: %s: block < 0", __func__);
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} else if (i_block < direct_blocks) {
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offsets[n++] = i_block;
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final = direct_blocks;
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} else if ( (i_block -= direct_blocks) < indirect_blocks) {
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offsets[n++] = EXT2_IND_BLOCK;
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offsets[n++] = i_block;
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final = ptrs;
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} else if ((i_block -= indirect_blocks) < double_blocks) {
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offsets[n++] = EXT2_DIND_BLOCK;
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offsets[n++] = i_block >> ptrs_bits;
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offsets[n++] = i_block & (ptrs - 1);
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final = ptrs;
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} else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) {
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offsets[n++] = EXT2_TIND_BLOCK;
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offsets[n++] = i_block >> (ptrs_bits * 2);
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offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1);
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offsets[n++] = i_block & (ptrs - 1);
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final = ptrs;
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} else {
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ext2_msg(inode->i_sb, KERN_WARNING,
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"warning: %s: block is too big", __func__);
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}
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if (boundary)
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*boundary = final - 1 - (i_block & (ptrs - 1));
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return n;
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}
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/**
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* ext2_get_branch - read the chain of indirect blocks leading to data
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* @inode: inode in question
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* @depth: depth of the chain (1 - direct pointer, etc.)
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* @offsets: offsets of pointers in inode/indirect blocks
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* @chain: place to store the result
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* @err: here we store the error value
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*
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* Function fills the array of triples <key, p, bh> and returns %NULL
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* if everything went OK or the pointer to the last filled triple
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* (incomplete one) otherwise. Upon the return chain[i].key contains
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* the number of (i+1)-th block in the chain (as it is stored in memory,
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* i.e. little-endian 32-bit), chain[i].p contains the address of that
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* number (it points into struct inode for i==0 and into the bh->b_data
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* for i>0) and chain[i].bh points to the buffer_head of i-th indirect
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* block for i>0 and NULL for i==0. In other words, it holds the block
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* numbers of the chain, addresses they were taken from (and where we can
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* verify that chain did not change) and buffer_heads hosting these
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* numbers.
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*
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* Function stops when it stumbles upon zero pointer (absent block)
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* (pointer to last triple returned, *@err == 0)
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* or when it gets an IO error reading an indirect block
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* (ditto, *@err == -EIO)
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* or when it notices that chain had been changed while it was reading
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* (ditto, *@err == -EAGAIN)
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* or when it reads all @depth-1 indirect blocks successfully and finds
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* the whole chain, all way to the data (returns %NULL, *err == 0).
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*/
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static Indirect *ext2_get_branch(struct inode *inode,
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int depth,
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int *offsets,
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Indirect chain[4],
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int *err)
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{
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struct super_block *sb = inode->i_sb;
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Indirect *p = chain;
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struct buffer_head *bh;
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*err = 0;
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/* i_data is not going away, no lock needed */
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add_chain (chain, NULL, EXT2_I(inode)->i_data + *offsets);
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if (!p->key)
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goto no_block;
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while (--depth) {
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bh = sb_bread(sb, le32_to_cpu(p->key));
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if (!bh)
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goto failure;
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read_lock(&EXT2_I(inode)->i_meta_lock);
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if (!verify_chain(chain, p))
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goto changed;
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add_chain(++p, bh, (__le32*)bh->b_data + *++offsets);
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read_unlock(&EXT2_I(inode)->i_meta_lock);
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if (!p->key)
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goto no_block;
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}
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return NULL;
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changed:
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read_unlock(&EXT2_I(inode)->i_meta_lock);
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brelse(bh);
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*err = -EAGAIN;
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goto no_block;
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failure:
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*err = -EIO;
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no_block:
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return p;
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}
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/**
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* ext2_find_near - find a place for allocation with sufficient locality
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* @inode: owner
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* @ind: descriptor of indirect block.
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*
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* This function returns the preferred place for block allocation.
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* It is used when heuristic for sequential allocation fails.
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* Rules are:
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* + if there is a block to the left of our position - allocate near it.
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* + if pointer will live in indirect block - allocate near that block.
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* + if pointer will live in inode - allocate in the same cylinder group.
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*
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* In the latter case we colour the starting block by the callers PID to
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* prevent it from clashing with concurrent allocations for a different inode
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* in the same block group. The PID is used here so that functionally related
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* files will be close-by on-disk.
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*
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* Caller must make sure that @ind is valid and will stay that way.
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*/
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static ext2_fsblk_t ext2_find_near(struct inode *inode, Indirect *ind)
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{
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struct ext2_inode_info *ei = EXT2_I(inode);
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__le32 *start = ind->bh ? (__le32 *) ind->bh->b_data : ei->i_data;
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__le32 *p;
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ext2_fsblk_t bg_start;
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ext2_fsblk_t colour;
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/* Try to find previous block */
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for (p = ind->p - 1; p >= start; p--)
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if (*p)
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return le32_to_cpu(*p);
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/* No such thing, so let's try location of indirect block */
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if (ind->bh)
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return ind->bh->b_blocknr;
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/*
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* It is going to be referred from inode itself? OK, just put it into
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* the same cylinder group then.
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*/
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bg_start = ext2_group_first_block_no(inode->i_sb, ei->i_block_group);
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colour = (current->pid % 16) *
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(EXT2_BLOCKS_PER_GROUP(inode->i_sb) / 16);
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return bg_start + colour;
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}
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/**
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* ext2_find_goal - find a preferred place for allocation.
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* @inode: owner
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* @block: block we want
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* @partial: pointer to the last triple within a chain
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*
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* Returns preferred place for a block (the goal).
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*/
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static inline ext2_fsblk_t ext2_find_goal(struct inode *inode, long block,
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Indirect *partial)
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{
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struct ext2_block_alloc_info *block_i;
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block_i = EXT2_I(inode)->i_block_alloc_info;
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/*
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* try the heuristic for sequential allocation,
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* failing that at least try to get decent locality.
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*/
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if (block_i && (block == block_i->last_alloc_logical_block + 1)
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&& (block_i->last_alloc_physical_block != 0)) {
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return block_i->last_alloc_physical_block + 1;
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}
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return ext2_find_near(inode, partial);
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}
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|
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/**
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* ext2_blks_to_allocate: Look up the block map and count the number
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* of direct blocks need to be allocated for the given branch.
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*
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* @branch: chain of indirect blocks
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* @k: number of blocks need for indirect blocks
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* @blks: number of data blocks to be mapped.
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* @blocks_to_boundary: the offset in the indirect block
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*
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* return the total number of blocks to be allocate, including the
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* direct and indirect blocks.
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*/
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static int
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ext2_blks_to_allocate(Indirect * branch, int k, unsigned long blks,
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int blocks_to_boundary)
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{
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unsigned long count = 0;
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|
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/*
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* Simple case, [t,d]Indirect block(s) has not allocated yet
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* then it's clear blocks on that path have not allocated
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*/
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if (k > 0) {
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/* right now don't hanel cross boundary allocation */
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if (blks < blocks_to_boundary + 1)
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count += blks;
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else
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count += blocks_to_boundary + 1;
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return count;
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}
|
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|
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count++;
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while (count < blks && count <= blocks_to_boundary
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&& le32_to_cpu(*(branch[0].p + count)) == 0) {
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count++;
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}
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return count;
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}
|
|
|
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/**
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* ext2_alloc_blocks: multiple allocate blocks needed for a branch
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* @indirect_blks: the number of blocks need to allocate for indirect
|
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* blocks
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*
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* @new_blocks: on return it will store the new block numbers for
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* the indirect blocks(if needed) and the first direct block,
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* @blks: on return it will store the total number of allocated
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* direct blocks
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*/
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static int ext2_alloc_blocks(struct inode *inode,
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ext2_fsblk_t goal, int indirect_blks, int blks,
|
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ext2_fsblk_t new_blocks[4], int *err)
|
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{
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int target, i;
|
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unsigned long count = 0;
|
|
int index = 0;
|
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ext2_fsblk_t current_block = 0;
|
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int ret = 0;
|
|
|
|
/*
|
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* Here we try to allocate the requested multiple blocks at once,
|
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* on a best-effort basis.
|
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* To build a branch, we should allocate blocks for
|
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* the indirect blocks(if not allocated yet), and at least
|
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* the first direct block of this branch. That's the
|
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* minimum number of blocks need to allocate(required)
|
|
*/
|
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target = blks + indirect_blks;
|
|
|
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while (1) {
|
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count = target;
|
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/* allocating blocks for indirect blocks and direct blocks */
|
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current_block = ext2_new_blocks(inode,goal,&count,err);
|
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if (*err)
|
|
goto failed_out;
|
|
|
|
target -= count;
|
|
/* allocate blocks for indirect blocks */
|
|
while (index < indirect_blks && count) {
|
|
new_blocks[index++] = current_block++;
|
|
count--;
|
|
}
|
|
|
|
if (count > 0)
|
|
break;
|
|
}
|
|
|
|
/* save the new block number for the first direct block */
|
|
new_blocks[index] = current_block;
|
|
|
|
/* total number of blocks allocated for direct blocks */
|
|
ret = count;
|
|
*err = 0;
|
|
return ret;
|
|
failed_out:
|
|
for (i = 0; i <index; i++)
|
|
ext2_free_blocks(inode, new_blocks[i], 1);
|
|
if (index)
|
|
mark_inode_dirty(inode);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* ext2_alloc_branch - allocate and set up a chain of blocks.
|
|
* @inode: owner
|
|
* @num: depth of the chain (number of blocks to allocate)
|
|
* @offsets: offsets (in the blocks) to store the pointers to next.
|
|
* @branch: place to store the chain in.
|
|
*
|
|
* This function allocates @num blocks, zeroes out all but the last one,
|
|
* links them into chain and (if we are synchronous) writes them to disk.
|
|
* In other words, it prepares a branch that can be spliced onto the
|
|
* inode. It stores the information about that chain in the branch[], in
|
|
* the same format as ext2_get_branch() would do. We are calling it after
|
|
* we had read the existing part of chain and partial points to the last
|
|
* triple of that (one with zero ->key). Upon the exit we have the same
|
|
* picture as after the successful ext2_get_block(), except that in one
|
|
* place chain is disconnected - *branch->p is still zero (we did not
|
|
* set the last link), but branch->key contains the number that should
|
|
* be placed into *branch->p to fill that gap.
|
|
*
|
|
* If allocation fails we free all blocks we've allocated (and forget
|
|
* their buffer_heads) and return the error value the from failed
|
|
* ext2_alloc_block() (normally -ENOSPC). Otherwise we set the chain
|
|
* as described above and return 0.
|
|
*/
|
|
|
|
static int ext2_alloc_branch(struct inode *inode,
|
|
int indirect_blks, int *blks, ext2_fsblk_t goal,
|
|
int *offsets, Indirect *branch)
|
|
{
|
|
int blocksize = inode->i_sb->s_blocksize;
|
|
int i, n = 0;
|
|
int err = 0;
|
|
struct buffer_head *bh;
|
|
int num;
|
|
ext2_fsblk_t new_blocks[4];
|
|
ext2_fsblk_t current_block;
|
|
|
|
num = ext2_alloc_blocks(inode, goal, indirect_blks,
|
|
*blks, new_blocks, &err);
|
|
if (err)
|
|
return err;
|
|
|
|
branch[0].key = cpu_to_le32(new_blocks[0]);
|
|
/*
|
|
* metadata blocks and data blocks are allocated.
|
|
*/
|
|
for (n = 1; n <= indirect_blks; n++) {
|
|
/*
|
|
* Get buffer_head for parent block, zero it out
|
|
* and set the pointer to new one, then send
|
|
* parent to disk.
|
|
*/
|
|
bh = sb_getblk(inode->i_sb, new_blocks[n-1]);
|
|
if (unlikely(!bh)) {
|
|
err = -ENOMEM;
|
|
goto failed;
|
|
}
|
|
branch[n].bh = bh;
|
|
lock_buffer(bh);
|
|
memset(bh->b_data, 0, blocksize);
|
|
branch[n].p = (__le32 *) bh->b_data + offsets[n];
|
|
branch[n].key = cpu_to_le32(new_blocks[n]);
|
|
*branch[n].p = branch[n].key;
|
|
if ( n == indirect_blks) {
|
|
current_block = new_blocks[n];
|
|
/*
|
|
* End of chain, update the last new metablock of
|
|
* the chain to point to the new allocated
|
|
* data blocks numbers
|
|
*/
|
|
for (i=1; i < num; i++)
|
|
*(branch[n].p + i) = cpu_to_le32(++current_block);
|
|
}
|
|
set_buffer_uptodate(bh);
|
|
unlock_buffer(bh);
|
|
mark_buffer_dirty_inode(bh, inode);
|
|
/* We used to sync bh here if IS_SYNC(inode).
|
|
* But we now rely upon generic_write_sync()
|
|
* and b_inode_buffers. But not for directories.
|
|
*/
|
|
if (S_ISDIR(inode->i_mode) && IS_DIRSYNC(inode))
|
|
sync_dirty_buffer(bh);
|
|
}
|
|
*blks = num;
|
|
return err;
|
|
|
|
failed:
|
|
for (i = 1; i < n; i++)
|
|
bforget(branch[i].bh);
|
|
for (i = 0; i < indirect_blks; i++)
|
|
ext2_free_blocks(inode, new_blocks[i], 1);
|
|
ext2_free_blocks(inode, new_blocks[i], num);
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* ext2_splice_branch - splice the allocated branch onto inode.
|
|
* @inode: owner
|
|
* @block: (logical) number of block we are adding
|
|
* @where: location of missing link
|
|
* @num: number of indirect blocks we are adding
|
|
* @blks: number of direct blocks we are adding
|
|
*
|
|
* This function fills the missing link and does all housekeeping needed in
|
|
* inode (->i_blocks, etc.). In case of success we end up with the full
|
|
* chain to new block and return 0.
|
|
*/
|
|
static void ext2_splice_branch(struct inode *inode,
|
|
long block, Indirect *where, int num, int blks)
|
|
{
|
|
int i;
|
|
struct ext2_block_alloc_info *block_i;
|
|
ext2_fsblk_t current_block;
|
|
|
|
block_i = EXT2_I(inode)->i_block_alloc_info;
|
|
|
|
/* XXX LOCKING probably should have i_meta_lock ?*/
|
|
/* That's it */
|
|
|
|
*where->p = where->key;
|
|
|
|
/*
|
|
* Update the host buffer_head or inode to point to more just allocated
|
|
* direct blocks blocks
|
|
*/
|
|
if (num == 0 && blks > 1) {
|
|
current_block = le32_to_cpu(where->key) + 1;
|
|
for (i = 1; i < blks; i++)
|
|
*(where->p + i ) = cpu_to_le32(current_block++);
|
|
}
|
|
|
|
/*
|
|
* update the most recently allocated logical & physical block
|
|
* in i_block_alloc_info, to assist find the proper goal block for next
|
|
* allocation
|
|
*/
|
|
if (block_i) {
|
|
block_i->last_alloc_logical_block = block + blks - 1;
|
|
block_i->last_alloc_physical_block =
|
|
le32_to_cpu(where[num].key) + blks - 1;
|
|
}
|
|
|
|
/* We are done with atomic stuff, now do the rest of housekeeping */
|
|
|
|
/* had we spliced it onto indirect block? */
|
|
if (where->bh)
|
|
mark_buffer_dirty_inode(where->bh, inode);
|
|
|
|
inode->i_ctime = CURRENT_TIME_SEC;
|
|
mark_inode_dirty(inode);
|
|
}
|
|
|
|
/*
|
|
* Allocation strategy is simple: if we have to allocate something, we will
|
|
* have to go the whole way to leaf. So let's do it before attaching anything
|
|
* to tree, set linkage between the newborn blocks, write them if sync is
|
|
* required, recheck the path, free and repeat if check fails, otherwise
|
|
* set the last missing link (that will protect us from any truncate-generated
|
|
* removals - all blocks on the path are immune now) and possibly force the
|
|
* write on the parent block.
|
|
* That has a nice additional property: no special recovery from the failed
|
|
* allocations is needed - we simply release blocks and do not touch anything
|
|
* reachable from inode.
|
|
*
|
|
* `handle' can be NULL if create == 0.
|
|
*
|
|
* return > 0, # of blocks mapped or allocated.
|
|
* return = 0, if plain lookup failed.
|
|
* return < 0, error case.
|
|
*/
|
|
static int ext2_get_blocks(struct inode *inode,
|
|
sector_t iblock, unsigned long maxblocks,
|
|
struct buffer_head *bh_result,
|
|
int create)
|
|
{
|
|
int err = -EIO;
|
|
int offsets[4];
|
|
Indirect chain[4];
|
|
Indirect *partial;
|
|
ext2_fsblk_t goal;
|
|
int indirect_blks;
|
|
int blocks_to_boundary = 0;
|
|
int depth;
|
|
struct ext2_inode_info *ei = EXT2_I(inode);
|
|
int count = 0;
|
|
ext2_fsblk_t first_block = 0;
|
|
|
|
depth = ext2_block_to_path(inode,iblock,offsets,&blocks_to_boundary);
|
|
|
|
if (depth == 0)
|
|
return (err);
|
|
|
|
partial = ext2_get_branch(inode, depth, offsets, chain, &err);
|
|
/* Simplest case - block found, no allocation needed */
|
|
if (!partial) {
|
|
first_block = le32_to_cpu(chain[depth - 1].key);
|
|
clear_buffer_new(bh_result); /* What's this do? */
|
|
count++;
|
|
/*map more blocks*/
|
|
while (count < maxblocks && count <= blocks_to_boundary) {
|
|
ext2_fsblk_t blk;
|
|
|
|
if (!verify_chain(chain, chain + depth - 1)) {
|
|
/*
|
|
* Indirect block might be removed by
|
|
* truncate while we were reading it.
|
|
* Handling of that case: forget what we've
|
|
* got now, go to reread.
|
|
*/
|
|
err = -EAGAIN;
|
|
count = 0;
|
|
break;
|
|
}
|
|
blk = le32_to_cpu(*(chain[depth-1].p + count));
|
|
if (blk == first_block + count)
|
|
count++;
|
|
else
|
|
break;
|
|
}
|
|
if (err != -EAGAIN)
|
|
goto got_it;
|
|
}
|
|
|
|
/* Next simple case - plain lookup or failed read of indirect block */
|
|
if (!create || err == -EIO)
|
|
goto cleanup;
|
|
|
|
mutex_lock(&ei->truncate_mutex);
|
|
/*
|
|
* If the indirect block is missing while we are reading
|
|
* the chain(ext2_get_branch() returns -EAGAIN err), or
|
|
* if the chain has been changed after we grab the semaphore,
|
|
* (either because another process truncated this branch, or
|
|
* another get_block allocated this branch) re-grab the chain to see if
|
|
* the request block has been allocated or not.
|
|
*
|
|
* Since we already block the truncate/other get_block
|
|
* at this point, we will have the current copy of the chain when we
|
|
* splice the branch into the tree.
|
|
*/
|
|
if (err == -EAGAIN || !verify_chain(chain, partial)) {
|
|
while (partial > chain) {
|
|
brelse(partial->bh);
|
|
partial--;
|
|
}
|
|
partial = ext2_get_branch(inode, depth, offsets, chain, &err);
|
|
if (!partial) {
|
|
count++;
|
|
mutex_unlock(&ei->truncate_mutex);
|
|
if (err)
|
|
goto cleanup;
|
|
clear_buffer_new(bh_result);
|
|
goto got_it;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Okay, we need to do block allocation. Lazily initialize the block
|
|
* allocation info here if necessary
|
|
*/
|
|
if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info))
|
|
ext2_init_block_alloc_info(inode);
|
|
|
|
goal = ext2_find_goal(inode, iblock, partial);
|
|
|
|
/* the number of blocks need to allocate for [d,t]indirect blocks */
|
|
indirect_blks = (chain + depth) - partial - 1;
|
|
/*
|
|
* Next look up the indirect map to count the totoal number of
|
|
* direct blocks to allocate for this branch.
|
|
*/
|
|
count = ext2_blks_to_allocate(partial, indirect_blks,
|
|
maxblocks, blocks_to_boundary);
|
|
/*
|
|
* XXX ???? Block out ext2_truncate while we alter the tree
|
|
*/
|
|
err = ext2_alloc_branch(inode, indirect_blks, &count, goal,
|
|
offsets + (partial - chain), partial);
|
|
|
|
if (err) {
|
|
mutex_unlock(&ei->truncate_mutex);
|
|
goto cleanup;
|
|
}
|
|
|
|
if (ext2_use_xip(inode->i_sb)) {
|
|
/*
|
|
* we need to clear the block
|
|
*/
|
|
err = ext2_clear_xip_target (inode,
|
|
le32_to_cpu(chain[depth-1].key));
|
|
if (err) {
|
|
mutex_unlock(&ei->truncate_mutex);
|
|
goto cleanup;
|
|
}
|
|
}
|
|
|
|
ext2_splice_branch(inode, iblock, partial, indirect_blks, count);
|
|
mutex_unlock(&ei->truncate_mutex);
|
|
set_buffer_new(bh_result);
|
|
got_it:
|
|
map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key));
|
|
if (count > blocks_to_boundary)
|
|
set_buffer_boundary(bh_result);
|
|
err = count;
|
|
/* Clean up and exit */
|
|
partial = chain + depth - 1; /* the whole chain */
|
|
cleanup:
|
|
while (partial > chain) {
|
|
brelse(partial->bh);
|
|
partial--;
|
|
}
|
|
return err;
|
|
}
|
|
|
|
int ext2_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create)
|
|
{
|
|
unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
|
|
int ret = ext2_get_blocks(inode, iblock, max_blocks,
|
|
bh_result, create);
|
|
if (ret > 0) {
|
|
bh_result->b_size = (ret << inode->i_blkbits);
|
|
ret = 0;
|
|
}
|
|
return ret;
|
|
|
|
}
|
|
|
|
int ext2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
|
|
u64 start, u64 len)
|
|
{
|
|
return generic_block_fiemap(inode, fieinfo, start, len,
|
|
ext2_get_block);
|
|
}
|
|
|
|
static int ext2_writepage(struct page *page, struct writeback_control *wbc)
|
|
{
|
|
return block_write_full_page(page, ext2_get_block, wbc);
|
|
}
|
|
|
|
static int ext2_readpage(struct file *file, struct page *page)
|
|
{
|
|
return mpage_readpage(page, ext2_get_block);
|
|
}
|
|
|
|
static int
|
|
ext2_readpages(struct file *file, struct address_space *mapping,
|
|
struct list_head *pages, unsigned nr_pages)
|
|
{
|
|
return mpage_readpages(mapping, pages, nr_pages, ext2_get_block);
|
|
}
|
|
|
|
static int
|
|
ext2_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata)
|
|
{
|
|
int ret;
|
|
|
|
ret = block_write_begin(mapping, pos, len, flags, pagep,
|
|
ext2_get_block);
|
|
if (ret < 0)
|
|
ext2_write_failed(mapping, pos + len);
|
|
return ret;
|
|
}
|
|
|
|
static int ext2_write_end(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
int ret;
|
|
|
|
ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
|
|
if (ret < len)
|
|
ext2_write_failed(mapping, pos + len);
|
|
return ret;
|
|
}
|
|
|
|
static int
|
|
ext2_nobh_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata)
|
|
{
|
|
int ret;
|
|
|
|
ret = nobh_write_begin(mapping, pos, len, flags, pagep, fsdata,
|
|
ext2_get_block);
|
|
if (ret < 0)
|
|
ext2_write_failed(mapping, pos + len);
|
|
return ret;
|
|
}
|
|
|
|
static int ext2_nobh_writepage(struct page *page,
|
|
struct writeback_control *wbc)
|
|
{
|
|
return nobh_writepage(page, ext2_get_block, wbc);
|
|
}
|
|
|
|
static sector_t ext2_bmap(struct address_space *mapping, sector_t block)
|
|
{
|
|
return generic_block_bmap(mapping,block,ext2_get_block);
|
|
}
|
|
|
|
static ssize_t
|
|
ext2_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 address_space *mapping = file->f_mapping;
|
|
struct inode *inode = mapping->host;
|
|
ssize_t ret;
|
|
|
|
ret = blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
|
|
ext2_get_block);
|
|
if (ret < 0 && (rw & WRITE))
|
|
ext2_write_failed(mapping, offset + iov_length(iov, nr_segs));
|
|
return ret;
|
|
}
|
|
|
|
static int
|
|
ext2_writepages(struct address_space *mapping, struct writeback_control *wbc)
|
|
{
|
|
return mpage_writepages(mapping, wbc, ext2_get_block);
|
|
}
|
|
|
|
const struct address_space_operations ext2_aops = {
|
|
.readpage = ext2_readpage,
|
|
.readpages = ext2_readpages,
|
|
.writepage = ext2_writepage,
|
|
.write_begin = ext2_write_begin,
|
|
.write_end = ext2_write_end,
|
|
.bmap = ext2_bmap,
|
|
.direct_IO = ext2_direct_IO,
|
|
.writepages = ext2_writepages,
|
|
.migratepage = buffer_migrate_page,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
const struct address_space_operations ext2_aops_xip = {
|
|
.bmap = ext2_bmap,
|
|
.get_xip_mem = ext2_get_xip_mem,
|
|
};
|
|
|
|
const struct address_space_operations ext2_nobh_aops = {
|
|
.readpage = ext2_readpage,
|
|
.readpages = ext2_readpages,
|
|
.writepage = ext2_nobh_writepage,
|
|
.write_begin = ext2_nobh_write_begin,
|
|
.write_end = nobh_write_end,
|
|
.bmap = ext2_bmap,
|
|
.direct_IO = ext2_direct_IO,
|
|
.writepages = ext2_writepages,
|
|
.migratepage = buffer_migrate_page,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
/*
|
|
* Probably it should be a library function... search for first non-zero word
|
|
* or memcmp with zero_page, whatever is better for particular architecture.
|
|
* Linus?
|
|
*/
|
|
static inline int all_zeroes(__le32 *p, __le32 *q)
|
|
{
|
|
while (p < q)
|
|
if (*p++)
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* ext2_find_shared - find the indirect blocks for partial truncation.
|
|
* @inode: inode in question
|
|
* @depth: depth of the affected branch
|
|
* @offsets: offsets of pointers in that branch (see ext2_block_to_path)
|
|
* @chain: place to store the pointers to partial indirect blocks
|
|
* @top: place to the (detached) top of branch
|
|
*
|
|
* This is a helper function used by ext2_truncate().
|
|
*
|
|
* When we do truncate() we may have to clean the ends of several indirect
|
|
* blocks but leave the blocks themselves alive. Block is partially
|
|
* truncated if some data below the new i_size is referred from it (and
|
|
* it is on the path to the first completely truncated data block, indeed).
|
|
* We have to free the top of that path along with everything to the right
|
|
* of the path. Since no allocation past the truncation point is possible
|
|
* until ext2_truncate() finishes, we may safely do the latter, but top
|
|
* of branch may require special attention - pageout below the truncation
|
|
* point might try to populate it.
|
|
*
|
|
* We atomically detach the top of branch from the tree, store the block
|
|
* number of its root in *@top, pointers to buffer_heads of partially
|
|
* truncated blocks - in @chain[].bh and pointers to their last elements
|
|
* that should not be removed - in @chain[].p. Return value is the pointer
|
|
* to last filled element of @chain.
|
|
*
|
|
* The work left to caller to do the actual freeing of subtrees:
|
|
* a) free the subtree starting from *@top
|
|
* b) free the subtrees whose roots are stored in
|
|
* (@chain[i].p+1 .. end of @chain[i].bh->b_data)
|
|
* c) free the subtrees growing from the inode past the @chain[0].p
|
|
* (no partially truncated stuff there).
|
|
*/
|
|
|
|
static Indirect *ext2_find_shared(struct inode *inode,
|
|
int depth,
|
|
int offsets[4],
|
|
Indirect chain[4],
|
|
__le32 *top)
|
|
{
|
|
Indirect *partial, *p;
|
|
int k, err;
|
|
|
|
*top = 0;
|
|
for (k = depth; k > 1 && !offsets[k-1]; k--)
|
|
;
|
|
partial = ext2_get_branch(inode, k, offsets, chain, &err);
|
|
if (!partial)
|
|
partial = chain + k-1;
|
|
/*
|
|
* If the branch acquired continuation since we've looked at it -
|
|
* fine, it should all survive and (new) top doesn't belong to us.
|
|
*/
|
|
write_lock(&EXT2_I(inode)->i_meta_lock);
|
|
if (!partial->key && *partial->p) {
|
|
write_unlock(&EXT2_I(inode)->i_meta_lock);
|
|
goto no_top;
|
|
}
|
|
for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--)
|
|
;
|
|
/*
|
|
* OK, we've found the last block that must survive. The rest of our
|
|
* branch should be detached before unlocking. However, if that rest
|
|
* of branch is all ours and does not grow immediately from the inode
|
|
* it's easier to cheat and just decrement partial->p.
|
|
*/
|
|
if (p == chain + k - 1 && p > chain) {
|
|
p->p--;
|
|
} else {
|
|
*top = *p->p;
|
|
*p->p = 0;
|
|
}
|
|
write_unlock(&EXT2_I(inode)->i_meta_lock);
|
|
|
|
while(partial > p)
|
|
{
|
|
brelse(partial->bh);
|
|
partial--;
|
|
}
|
|
no_top:
|
|
return partial;
|
|
}
|
|
|
|
/**
|
|
* ext2_free_data - free a list of data blocks
|
|
* @inode: inode we are dealing with
|
|
* @p: array of block numbers
|
|
* @q: points immediately past the end of array
|
|
*
|
|
* We are freeing all blocks referred from that array (numbers are
|
|
* stored as little-endian 32-bit) and updating @inode->i_blocks
|
|
* appropriately.
|
|
*/
|
|
static inline void ext2_free_data(struct inode *inode, __le32 *p, __le32 *q)
|
|
{
|
|
unsigned long block_to_free = 0, count = 0;
|
|
unsigned long nr;
|
|
|
|
for ( ; p < q ; p++) {
|
|
nr = le32_to_cpu(*p);
|
|
if (nr) {
|
|
*p = 0;
|
|
/* accumulate blocks to free if they're contiguous */
|
|
if (count == 0)
|
|
goto free_this;
|
|
else if (block_to_free == nr - count)
|
|
count++;
|
|
else {
|
|
ext2_free_blocks (inode, block_to_free, count);
|
|
mark_inode_dirty(inode);
|
|
free_this:
|
|
block_to_free = nr;
|
|
count = 1;
|
|
}
|
|
}
|
|
}
|
|
if (count > 0) {
|
|
ext2_free_blocks (inode, block_to_free, count);
|
|
mark_inode_dirty(inode);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* ext2_free_branches - free an array of branches
|
|
* @inode: inode we are dealing with
|
|
* @p: array of block numbers
|
|
* @q: pointer immediately past the end of array
|
|
* @depth: depth of the branches to free
|
|
*
|
|
* We are freeing all blocks referred from these branches (numbers are
|
|
* stored as little-endian 32-bit) and updating @inode->i_blocks
|
|
* appropriately.
|
|
*/
|
|
static void ext2_free_branches(struct inode *inode, __le32 *p, __le32 *q, int depth)
|
|
{
|
|
struct buffer_head * bh;
|
|
unsigned long nr;
|
|
|
|
if (depth--) {
|
|
int addr_per_block = EXT2_ADDR_PER_BLOCK(inode->i_sb);
|
|
for ( ; p < q ; p++) {
|
|
nr = le32_to_cpu(*p);
|
|
if (!nr)
|
|
continue;
|
|
*p = 0;
|
|
bh = sb_bread(inode->i_sb, nr);
|
|
/*
|
|
* A read failure? Report error and clear slot
|
|
* (should be rare).
|
|
*/
|
|
if (!bh) {
|
|
ext2_error(inode->i_sb, "ext2_free_branches",
|
|
"Read failure, inode=%ld, block=%ld",
|
|
inode->i_ino, nr);
|
|
continue;
|
|
}
|
|
ext2_free_branches(inode,
|
|
(__le32*)bh->b_data,
|
|
(__le32*)bh->b_data + addr_per_block,
|
|
depth);
|
|
bforget(bh);
|
|
ext2_free_blocks(inode, nr, 1);
|
|
mark_inode_dirty(inode);
|
|
}
|
|
} else
|
|
ext2_free_data(inode, p, q);
|
|
}
|
|
|
|
static void __ext2_truncate_blocks(struct inode *inode, loff_t offset)
|
|
{
|
|
__le32 *i_data = EXT2_I(inode)->i_data;
|
|
struct ext2_inode_info *ei = EXT2_I(inode);
|
|
int addr_per_block = EXT2_ADDR_PER_BLOCK(inode->i_sb);
|
|
int offsets[4];
|
|
Indirect chain[4];
|
|
Indirect *partial;
|
|
__le32 nr = 0;
|
|
int n;
|
|
long iblock;
|
|
unsigned blocksize;
|
|
blocksize = inode->i_sb->s_blocksize;
|
|
iblock = (offset + blocksize-1) >> EXT2_BLOCK_SIZE_BITS(inode->i_sb);
|
|
|
|
n = ext2_block_to_path(inode, iblock, offsets, NULL);
|
|
if (n == 0)
|
|
return;
|
|
|
|
/*
|
|
* From here we block out all ext2_get_block() callers who want to
|
|
* modify the block allocation tree.
|
|
*/
|
|
mutex_lock(&ei->truncate_mutex);
|
|
|
|
if (n == 1) {
|
|
ext2_free_data(inode, i_data+offsets[0],
|
|
i_data + EXT2_NDIR_BLOCKS);
|
|
goto do_indirects;
|
|
}
|
|
|
|
partial = ext2_find_shared(inode, n, offsets, chain, &nr);
|
|
/* Kill the top of shared branch (already detached) */
|
|
if (nr) {
|
|
if (partial == chain)
|
|
mark_inode_dirty(inode);
|
|
else
|
|
mark_buffer_dirty_inode(partial->bh, inode);
|
|
ext2_free_branches(inode, &nr, &nr+1, (chain+n-1) - partial);
|
|
}
|
|
/* Clear the ends of indirect blocks on the shared branch */
|
|
while (partial > chain) {
|
|
ext2_free_branches(inode,
|
|
partial->p + 1,
|
|
(__le32*)partial->bh->b_data+addr_per_block,
|
|
(chain+n-1) - partial);
|
|
mark_buffer_dirty_inode(partial->bh, inode);
|
|
brelse (partial->bh);
|
|
partial--;
|
|
}
|
|
do_indirects:
|
|
/* Kill the remaining (whole) subtrees */
|
|
switch (offsets[0]) {
|
|
default:
|
|
nr = i_data[EXT2_IND_BLOCK];
|
|
if (nr) {
|
|
i_data[EXT2_IND_BLOCK] = 0;
|
|
mark_inode_dirty(inode);
|
|
ext2_free_branches(inode, &nr, &nr+1, 1);
|
|
}
|
|
case EXT2_IND_BLOCK:
|
|
nr = i_data[EXT2_DIND_BLOCK];
|
|
if (nr) {
|
|
i_data[EXT2_DIND_BLOCK] = 0;
|
|
mark_inode_dirty(inode);
|
|
ext2_free_branches(inode, &nr, &nr+1, 2);
|
|
}
|
|
case EXT2_DIND_BLOCK:
|
|
nr = i_data[EXT2_TIND_BLOCK];
|
|
if (nr) {
|
|
i_data[EXT2_TIND_BLOCK] = 0;
|
|
mark_inode_dirty(inode);
|
|
ext2_free_branches(inode, &nr, &nr+1, 3);
|
|
}
|
|
case EXT2_TIND_BLOCK:
|
|
;
|
|
}
|
|
|
|
ext2_discard_reservation(inode);
|
|
|
|
mutex_unlock(&ei->truncate_mutex);
|
|
}
|
|
|
|
static void ext2_truncate_blocks(struct inode *inode, loff_t offset)
|
|
{
|
|
/*
|
|
* XXX: it seems like a bug here that we don't allow
|
|
* IS_APPEND inode to have blocks-past-i_size trimmed off.
|
|
* review and fix this.
|
|
*
|
|
* Also would be nice to be able to handle IO errors and such,
|
|
* but that's probably too much to ask.
|
|
*/
|
|
if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
|
|
S_ISLNK(inode->i_mode)))
|
|
return;
|
|
if (ext2_inode_is_fast_symlink(inode))
|
|
return;
|
|
if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
|
|
return;
|
|
__ext2_truncate_blocks(inode, offset);
|
|
}
|
|
|
|
static int ext2_setsize(struct inode *inode, loff_t newsize)
|
|
{
|
|
int error;
|
|
|
|
if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
|
|
S_ISLNK(inode->i_mode)))
|
|
return -EINVAL;
|
|
if (ext2_inode_is_fast_symlink(inode))
|
|
return -EINVAL;
|
|
if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
|
|
return -EPERM;
|
|
|
|
inode_dio_wait(inode);
|
|
|
|
if (mapping_is_xip(inode->i_mapping))
|
|
error = xip_truncate_page(inode->i_mapping, newsize);
|
|
else if (test_opt(inode->i_sb, NOBH))
|
|
error = nobh_truncate_page(inode->i_mapping,
|
|
newsize, ext2_get_block);
|
|
else
|
|
error = block_truncate_page(inode->i_mapping,
|
|
newsize, ext2_get_block);
|
|
if (error)
|
|
return error;
|
|
|
|
truncate_setsize(inode, newsize);
|
|
__ext2_truncate_blocks(inode, newsize);
|
|
|
|
inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
|
|
if (inode_needs_sync(inode)) {
|
|
sync_mapping_buffers(inode->i_mapping);
|
|
sync_inode_metadata(inode, 1);
|
|
} else {
|
|
mark_inode_dirty(inode);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct ext2_inode *ext2_get_inode(struct super_block *sb, ino_t ino,
|
|
struct buffer_head **p)
|
|
{
|
|
struct buffer_head * bh;
|
|
unsigned long block_group;
|
|
unsigned long block;
|
|
unsigned long offset;
|
|
struct ext2_group_desc * gdp;
|
|
|
|
*p = NULL;
|
|
if ((ino != EXT2_ROOT_INO && ino < EXT2_FIRST_INO(sb)) ||
|
|
ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
|
|
goto Einval;
|
|
|
|
block_group = (ino - 1) / EXT2_INODES_PER_GROUP(sb);
|
|
gdp = ext2_get_group_desc(sb, block_group, NULL);
|
|
if (!gdp)
|
|
goto Egdp;
|
|
/*
|
|
* Figure out the offset within the block group inode table
|
|
*/
|
|
offset = ((ino - 1) % EXT2_INODES_PER_GROUP(sb)) * EXT2_INODE_SIZE(sb);
|
|
block = le32_to_cpu(gdp->bg_inode_table) +
|
|
(offset >> EXT2_BLOCK_SIZE_BITS(sb));
|
|
if (!(bh = sb_bread(sb, block)))
|
|
goto Eio;
|
|
|
|
*p = bh;
|
|
offset &= (EXT2_BLOCK_SIZE(sb) - 1);
|
|
return (struct ext2_inode *) (bh->b_data + offset);
|
|
|
|
Einval:
|
|
ext2_error(sb, "ext2_get_inode", "bad inode number: %lu",
|
|
(unsigned long) ino);
|
|
return ERR_PTR(-EINVAL);
|
|
Eio:
|
|
ext2_error(sb, "ext2_get_inode",
|
|
"unable to read inode block - inode=%lu, block=%lu",
|
|
(unsigned long) ino, block);
|
|
Egdp:
|
|
return ERR_PTR(-EIO);
|
|
}
|
|
|
|
void ext2_set_inode_flags(struct inode *inode)
|
|
{
|
|
unsigned int flags = EXT2_I(inode)->i_flags;
|
|
|
|
inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
|
|
if (flags & EXT2_SYNC_FL)
|
|
inode->i_flags |= S_SYNC;
|
|
if (flags & EXT2_APPEND_FL)
|
|
inode->i_flags |= S_APPEND;
|
|
if (flags & EXT2_IMMUTABLE_FL)
|
|
inode->i_flags |= S_IMMUTABLE;
|
|
if (flags & EXT2_NOATIME_FL)
|
|
inode->i_flags |= S_NOATIME;
|
|
if (flags & EXT2_DIRSYNC_FL)
|
|
inode->i_flags |= S_DIRSYNC;
|
|
}
|
|
|
|
/* Propagate flags from i_flags to EXT2_I(inode)->i_flags */
|
|
void ext2_get_inode_flags(struct ext2_inode_info *ei)
|
|
{
|
|
unsigned int flags = ei->vfs_inode.i_flags;
|
|
|
|
ei->i_flags &= ~(EXT2_SYNC_FL|EXT2_APPEND_FL|
|
|
EXT2_IMMUTABLE_FL|EXT2_NOATIME_FL|EXT2_DIRSYNC_FL);
|
|
if (flags & S_SYNC)
|
|
ei->i_flags |= EXT2_SYNC_FL;
|
|
if (flags & S_APPEND)
|
|
ei->i_flags |= EXT2_APPEND_FL;
|
|
if (flags & S_IMMUTABLE)
|
|
ei->i_flags |= EXT2_IMMUTABLE_FL;
|
|
if (flags & S_NOATIME)
|
|
ei->i_flags |= EXT2_NOATIME_FL;
|
|
if (flags & S_DIRSYNC)
|
|
ei->i_flags |= EXT2_DIRSYNC_FL;
|
|
}
|
|
|
|
struct inode *ext2_iget (struct super_block *sb, unsigned long ino)
|
|
{
|
|
struct ext2_inode_info *ei;
|
|
struct buffer_head * bh;
|
|
struct ext2_inode *raw_inode;
|
|
struct inode *inode;
|
|
long ret = -EIO;
|
|
int n;
|
|
uid_t i_uid;
|
|
gid_t i_gid;
|
|
|
|
inode = iget_locked(sb, ino);
|
|
if (!inode)
|
|
return ERR_PTR(-ENOMEM);
|
|
if (!(inode->i_state & I_NEW))
|
|
return inode;
|
|
|
|
ei = EXT2_I(inode);
|
|
ei->i_block_alloc_info = NULL;
|
|
|
|
raw_inode = ext2_get_inode(inode->i_sb, ino, &bh);
|
|
if (IS_ERR(raw_inode)) {
|
|
ret = PTR_ERR(raw_inode);
|
|
goto bad_inode;
|
|
}
|
|
|
|
inode->i_mode = le16_to_cpu(raw_inode->i_mode);
|
|
i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
|
|
i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
|
|
if (!(test_opt (inode->i_sb, NO_UID32))) {
|
|
i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
|
|
i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
|
|
}
|
|
i_uid_write(inode, i_uid);
|
|
i_gid_write(inode, i_gid);
|
|
set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
|
|
inode->i_size = le32_to_cpu(raw_inode->i_size);
|
|
inode->i_atime.tv_sec = (signed)le32_to_cpu(raw_inode->i_atime);
|
|
inode->i_ctime.tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime);
|
|
inode->i_mtime.tv_sec = (signed)le32_to_cpu(raw_inode->i_mtime);
|
|
inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = 0;
|
|
ei->i_dtime = le32_to_cpu(raw_inode->i_dtime);
|
|
/* We now have enough fields to check if the inode was active or not.
|
|
* This is needed because nfsd might try to access dead inodes
|
|
* the test is that same one that e2fsck uses
|
|
* NeilBrown 1999oct15
|
|
*/
|
|
if (inode->i_nlink == 0 && (inode->i_mode == 0 || ei->i_dtime)) {
|
|
/* this inode is deleted */
|
|
brelse (bh);
|
|
ret = -ESTALE;
|
|
goto bad_inode;
|
|
}
|
|
inode->i_blocks = le32_to_cpu(raw_inode->i_blocks);
|
|
ei->i_flags = le32_to_cpu(raw_inode->i_flags);
|
|
ei->i_faddr = le32_to_cpu(raw_inode->i_faddr);
|
|
ei->i_frag_no = raw_inode->i_frag;
|
|
ei->i_frag_size = raw_inode->i_fsize;
|
|
ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
|
|
ei->i_dir_acl = 0;
|
|
if (S_ISREG(inode->i_mode))
|
|
inode->i_size |= ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32;
|
|
else
|
|
ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl);
|
|
ei->i_dtime = 0;
|
|
inode->i_generation = le32_to_cpu(raw_inode->i_generation);
|
|
ei->i_state = 0;
|
|
ei->i_block_group = (ino - 1) / EXT2_INODES_PER_GROUP(inode->i_sb);
|
|
ei->i_dir_start_lookup = 0;
|
|
|
|
/*
|
|
* NOTE! The in-memory inode i_data array is in little-endian order
|
|
* even on big-endian machines: we do NOT byteswap the block numbers!
|
|
*/
|
|
for (n = 0; n < EXT2_N_BLOCKS; n++)
|
|
ei->i_data[n] = raw_inode->i_block[n];
|
|
|
|
if (S_ISREG(inode->i_mode)) {
|
|
inode->i_op = &ext2_file_inode_operations;
|
|
if (ext2_use_xip(inode->i_sb)) {
|
|
inode->i_mapping->a_ops = &ext2_aops_xip;
|
|
inode->i_fop = &ext2_xip_file_operations;
|
|
} else if (test_opt(inode->i_sb, NOBH)) {
|
|
inode->i_mapping->a_ops = &ext2_nobh_aops;
|
|
inode->i_fop = &ext2_file_operations;
|
|
} else {
|
|
inode->i_mapping->a_ops = &ext2_aops;
|
|
inode->i_fop = &ext2_file_operations;
|
|
}
|
|
} else if (S_ISDIR(inode->i_mode)) {
|
|
inode->i_op = &ext2_dir_inode_operations;
|
|
inode->i_fop = &ext2_dir_operations;
|
|
if (test_opt(inode->i_sb, NOBH))
|
|
inode->i_mapping->a_ops = &ext2_nobh_aops;
|
|
else
|
|
inode->i_mapping->a_ops = &ext2_aops;
|
|
} else if (S_ISLNK(inode->i_mode)) {
|
|
if (ext2_inode_is_fast_symlink(inode)) {
|
|
inode->i_op = &ext2_fast_symlink_inode_operations;
|
|
nd_terminate_link(ei->i_data, inode->i_size,
|
|
sizeof(ei->i_data) - 1);
|
|
} else {
|
|
inode->i_op = &ext2_symlink_inode_operations;
|
|
if (test_opt(inode->i_sb, NOBH))
|
|
inode->i_mapping->a_ops = &ext2_nobh_aops;
|
|
else
|
|
inode->i_mapping->a_ops = &ext2_aops;
|
|
}
|
|
} else {
|
|
inode->i_op = &ext2_special_inode_operations;
|
|
if (raw_inode->i_block[0])
|
|
init_special_inode(inode, inode->i_mode,
|
|
old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
|
|
else
|
|
init_special_inode(inode, inode->i_mode,
|
|
new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
|
|
}
|
|
brelse (bh);
|
|
ext2_set_inode_flags(inode);
|
|
unlock_new_inode(inode);
|
|
return inode;
|
|
|
|
bad_inode:
|
|
iget_failed(inode);
|
|
return ERR_PTR(ret);
|
|
}
|
|
|
|
static int __ext2_write_inode(struct inode *inode, int do_sync)
|
|
{
|
|
struct ext2_inode_info *ei = EXT2_I(inode);
|
|
struct super_block *sb = inode->i_sb;
|
|
ino_t ino = inode->i_ino;
|
|
uid_t uid = i_uid_read(inode);
|
|
gid_t gid = i_gid_read(inode);
|
|
struct buffer_head * bh;
|
|
struct ext2_inode * raw_inode = ext2_get_inode(sb, ino, &bh);
|
|
int n;
|
|
int err = 0;
|
|
|
|
if (IS_ERR(raw_inode))
|
|
return -EIO;
|
|
|
|
/* For fields not not tracking in the in-memory inode,
|
|
* initialise them to zero for new inodes. */
|
|
if (ei->i_state & EXT2_STATE_NEW)
|
|
memset(raw_inode, 0, EXT2_SB(sb)->s_inode_size);
|
|
|
|
ext2_get_inode_flags(ei);
|
|
raw_inode->i_mode = cpu_to_le16(inode->i_mode);
|
|
if (!(test_opt(sb, NO_UID32))) {
|
|
raw_inode->i_uid_low = cpu_to_le16(low_16_bits(uid));
|
|
raw_inode->i_gid_low = cpu_to_le16(low_16_bits(gid));
|
|
/*
|
|
* Fix up interoperability with old kernels. Otherwise, old inodes get
|
|
* re-used with the upper 16 bits of the uid/gid intact
|
|
*/
|
|
if (!ei->i_dtime) {
|
|
raw_inode->i_uid_high = cpu_to_le16(high_16_bits(uid));
|
|
raw_inode->i_gid_high = cpu_to_le16(high_16_bits(gid));
|
|
} else {
|
|
raw_inode->i_uid_high = 0;
|
|
raw_inode->i_gid_high = 0;
|
|
}
|
|
} else {
|
|
raw_inode->i_uid_low = cpu_to_le16(fs_high2lowuid(uid));
|
|
raw_inode->i_gid_low = cpu_to_le16(fs_high2lowgid(gid));
|
|
raw_inode->i_uid_high = 0;
|
|
raw_inode->i_gid_high = 0;
|
|
}
|
|
raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
|
|
raw_inode->i_size = cpu_to_le32(inode->i_size);
|
|
raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
|
|
raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
|
|
raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
|
|
|
|
raw_inode->i_blocks = cpu_to_le32(inode->i_blocks);
|
|
raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
|
|
raw_inode->i_flags = cpu_to_le32(ei->i_flags);
|
|
raw_inode->i_faddr = cpu_to_le32(ei->i_faddr);
|
|
raw_inode->i_frag = ei->i_frag_no;
|
|
raw_inode->i_fsize = ei->i_frag_size;
|
|
raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl);
|
|
if (!S_ISREG(inode->i_mode))
|
|
raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl);
|
|
else {
|
|
raw_inode->i_size_high = cpu_to_le32(inode->i_size >> 32);
|
|
if (inode->i_size > 0x7fffffffULL) {
|
|
if (!EXT2_HAS_RO_COMPAT_FEATURE(sb,
|
|
EXT2_FEATURE_RO_COMPAT_LARGE_FILE) ||
|
|
EXT2_SB(sb)->s_es->s_rev_level ==
|
|
cpu_to_le32(EXT2_GOOD_OLD_REV)) {
|
|
/* If this is the first large file
|
|
* created, add a flag to the superblock.
|
|
*/
|
|
spin_lock(&EXT2_SB(sb)->s_lock);
|
|
ext2_update_dynamic_rev(sb);
|
|
EXT2_SET_RO_COMPAT_FEATURE(sb,
|
|
EXT2_FEATURE_RO_COMPAT_LARGE_FILE);
|
|
spin_unlock(&EXT2_SB(sb)->s_lock);
|
|
ext2_write_super(sb);
|
|
}
|
|
}
|
|
}
|
|
|
|
raw_inode->i_generation = cpu_to_le32(inode->i_generation);
|
|
if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
|
|
if (old_valid_dev(inode->i_rdev)) {
|
|
raw_inode->i_block[0] =
|
|
cpu_to_le32(old_encode_dev(inode->i_rdev));
|
|
raw_inode->i_block[1] = 0;
|
|
} else {
|
|
raw_inode->i_block[0] = 0;
|
|
raw_inode->i_block[1] =
|
|
cpu_to_le32(new_encode_dev(inode->i_rdev));
|
|
raw_inode->i_block[2] = 0;
|
|
}
|
|
} else for (n = 0; n < EXT2_N_BLOCKS; n++)
|
|
raw_inode->i_block[n] = ei->i_data[n];
|
|
mark_buffer_dirty(bh);
|
|
if (do_sync) {
|
|
sync_dirty_buffer(bh);
|
|
if (buffer_req(bh) && !buffer_uptodate(bh)) {
|
|
printk ("IO error syncing ext2 inode [%s:%08lx]\n",
|
|
sb->s_id, (unsigned long) ino);
|
|
err = -EIO;
|
|
}
|
|
}
|
|
ei->i_state &= ~EXT2_STATE_NEW;
|
|
brelse (bh);
|
|
return err;
|
|
}
|
|
|
|
int ext2_write_inode(struct inode *inode, struct writeback_control *wbc)
|
|
{
|
|
return __ext2_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
|
|
}
|
|
|
|
int ext2_setattr(struct dentry *dentry, struct iattr *iattr)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
int error;
|
|
|
|
error = inode_change_ok(inode, iattr);
|
|
if (error)
|
|
return error;
|
|
|
|
if (is_quota_modification(inode, iattr))
|
|
dquot_initialize(inode);
|
|
if ((iattr->ia_valid & ATTR_UID && !uid_eq(iattr->ia_uid, inode->i_uid)) ||
|
|
(iattr->ia_valid & ATTR_GID && !gid_eq(iattr->ia_gid, inode->i_gid))) {
|
|
error = dquot_transfer(inode, iattr);
|
|
if (error)
|
|
return error;
|
|
}
|
|
if (iattr->ia_valid & ATTR_SIZE && iattr->ia_size != inode->i_size) {
|
|
error = ext2_setsize(inode, iattr->ia_size);
|
|
if (error)
|
|
return error;
|
|
}
|
|
setattr_copy(inode, iattr);
|
|
if (iattr->ia_valid & ATTR_MODE)
|
|
error = ext2_acl_chmod(inode);
|
|
mark_inode_dirty(inode);
|
|
|
|
return error;
|
|
}
|