| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * linux/fs/ext2/inode.c |
| * |
| * Copyright (C) 1992, 1993, 1994, 1995 |
| * Remy Card (card@masi.ibp.fr) |
| * Laboratoire MASI - Institut Blaise Pascal |
| * Universite Pierre et Marie Curie (Paris VI) |
| * |
| * from |
| * |
| * linux/fs/minix/inode.c |
| * |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| * |
| * Goal-directed block allocation by Stephen Tweedie |
| * (sct@dcs.ed.ac.uk), 1993, 1998 |
| * Big-endian to little-endian byte-swapping/bitmaps by |
| * David S. Miller (davem@caip.rutgers.edu), 1995 |
| * 64-bit file support on 64-bit platforms by Jakub Jelinek |
| * (jj@sunsite.ms.mff.cuni.cz) |
| * |
| * Assorted race fixes, rewrite of ext2_get_block() by Al Viro, 2000 |
| */ |
| |
| #include <linux/time.h> |
| #include <linux/highuid.h> |
| #include <linux/pagemap.h> |
| #include <linux/dax.h> |
| #include <linux/blkdev.h> |
| #include <linux/quotaops.h> |
| #include <linux/writeback.h> |
| #include <linux/buffer_head.h> |
| #include <linux/mpage.h> |
| #include <linux/fiemap.h> |
| #include <linux/iomap.h> |
| #include <linux/namei.h> |
| #include <linux/uio.h> |
| #include "ext2.h" |
| #include "acl.h" |
| #include "xattr.h" |
| |
| static int __ext2_write_inode(struct inode *inode, int do_sync); |
| |
| /* |
| * Test whether an inode is a fast symlink. |
| */ |
| static inline int ext2_inode_is_fast_symlink(struct inode *inode) |
| { |
| int ea_blocks = EXT2_I(inode)->i_file_acl ? |
| (inode->i_sb->s_blocksize >> 9) : 0; |
| |
| return (S_ISLNK(inode->i_mode) && |
| inode->i_blocks - ea_blocks == 0); |
| } |
| |
| static void ext2_truncate_blocks(struct inode *inode, loff_t offset); |
| |
| static void ext2_write_failed(struct address_space *mapping, loff_t to) |
| { |
| struct inode *inode = mapping->host; |
| |
| if (to > inode->i_size) { |
| truncate_pagecache(inode, inode->i_size); |
| ext2_truncate_blocks(inode, inode->i_size); |
| } |
| } |
| |
| /* |
| * Called at the last iput() if i_nlink is zero. |
| */ |
| void ext2_evict_inode(struct inode * inode) |
| { |
| struct ext2_block_alloc_info *rsv; |
| int want_delete = 0; |
| |
| if (!inode->i_nlink && !is_bad_inode(inode)) { |
| want_delete = 1; |
| dquot_initialize(inode); |
| } else { |
| dquot_drop(inode); |
| } |
| |
| truncate_inode_pages_final(&inode->i_data); |
| |
| if (want_delete) { |
| sb_start_intwrite(inode->i_sb); |
| /* set dtime */ |
| EXT2_I(inode)->i_dtime = ktime_get_real_seconds(); |
| mark_inode_dirty(inode); |
| __ext2_write_inode(inode, inode_needs_sync(inode)); |
| /* truncate to 0 */ |
| inode->i_size = 0; |
| if (inode->i_blocks) |
| ext2_truncate_blocks(inode, 0); |
| ext2_xattr_delete_inode(inode); |
| } |
| |
| invalidate_inode_buffers(inode); |
| clear_inode(inode); |
| |
| ext2_discard_reservation(inode); |
| rsv = EXT2_I(inode)->i_block_alloc_info; |
| EXT2_I(inode)->i_block_alloc_info = NULL; |
| if (unlikely(rsv)) |
| kfree(rsv); |
| |
| if (want_delete) { |
| ext2_free_inode(inode); |
| sb_end_intwrite(inode->i_sb); |
| } |
| } |
| |
| typedef struct { |
| __le32 *p; |
| __le32 key; |
| struct buffer_head *bh; |
| } Indirect; |
| |
| static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v) |
| { |
| p->key = *(p->p = v); |
| p->bh = bh; |
| } |
| |
| static inline int verify_chain(Indirect *from, Indirect *to) |
| { |
| while (from <= to && from->key == *from->p) |
| from++; |
| return (from > to); |
| } |
| |
| /** |
| * ext2_block_to_path - parse the block number into array of offsets |
| * @inode: inode in question (we are only interested in its superblock) |
| * @i_block: block number to be parsed |
| * @offsets: array to store the offsets in |
| * @boundary: set this non-zero if the referred-to block is likely to be |
| * followed (on disk) by an indirect block. |
| * To store the locations of file's data ext2 uses a data structure common |
| * for UNIX filesystems - tree of pointers anchored in the inode, with |
| * data blocks at leaves and indirect blocks in intermediate nodes. |
| * This function translates the block number into path in that tree - |
| * return value is the path length and @offsets[n] is the offset of |
| * pointer to (n+1)th node in the nth one. If @block is out of range |
| * (negative or too large) warning is printed and zero returned. |
| * |
| * Note: function doesn't find node addresses, so no IO is needed. All |
| * we need to know is the capacity of indirect blocks (taken from the |
| * inode->i_sb). |
| */ |
| |
| /* |
| * Portability note: the last comparison (check that we fit into triple |
| * indirect block) is spelled differently, because otherwise on an |
| * architecture with 32-bit longs and 8Kb pages we might get into trouble |
| * if our filesystem had 8Kb blocks. We might use long long, but that would |
| * kill us on x86. Oh, well, at least the sign propagation does not matter - |
| * i_block would have to be negative in the very beginning, so we would not |
| * get there at all. |
| */ |
| |
| static int ext2_block_to_path(struct inode *inode, |
| long i_block, int offsets[4], int *boundary) |
| { |
| int ptrs = EXT2_ADDR_PER_BLOCK(inode->i_sb); |
| int ptrs_bits = EXT2_ADDR_PER_BLOCK_BITS(inode->i_sb); |
| const long direct_blocks = EXT2_NDIR_BLOCKS, |
| indirect_blocks = ptrs, |
| double_blocks = (1 << (ptrs_bits * 2)); |
| int n = 0; |
| int final = 0; |
| |
| if (i_block < 0) { |
| ext2_msg(inode->i_sb, KERN_WARNING, |
| "warning: %s: block < 0", __func__); |
| } else if (i_block < direct_blocks) { |
| offsets[n++] = i_block; |
| final = direct_blocks; |
| } else if ( (i_block -= direct_blocks) < indirect_blocks) { |
| offsets[n++] = EXT2_IND_BLOCK; |
| offsets[n++] = i_block; |
| final = ptrs; |
| } else if ((i_block -= indirect_blocks) < double_blocks) { |
| offsets[n++] = EXT2_DIND_BLOCK; |
| offsets[n++] = i_block >> ptrs_bits; |
| offsets[n++] = i_block & (ptrs - 1); |
| final = ptrs; |
| } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) { |
| offsets[n++] = EXT2_TIND_BLOCK; |
| offsets[n++] = i_block >> (ptrs_bits * 2); |
| offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1); |
| offsets[n++] = i_block & (ptrs - 1); |
| final = ptrs; |
| } else { |
| ext2_msg(inode->i_sb, KERN_WARNING, |
| "warning: %s: block is too big", __func__); |
| } |
| if (boundary) |
| *boundary = final - 1 - (i_block & (ptrs - 1)); |
| |
| return n; |
| } |
| |
| /** |
| * ext2_get_branch - read the chain of indirect blocks leading to data |
| * @inode: inode in question |
| * @depth: depth of the chain (1 - direct pointer, etc.) |
| * @offsets: offsets of pointers in inode/indirect blocks |
| * @chain: place to store the result |
| * @err: here we store the error value |
| * |
| * Function fills the array of triples <key, p, bh> and returns %NULL |
| * if everything went OK or the pointer to the last filled triple |
| * (incomplete one) otherwise. Upon the return chain[i].key contains |
| * the number of (i+1)-th block in the chain (as it is stored in memory, |
| * i.e. little-endian 32-bit), chain[i].p contains the address of that |
| * number (it points into struct inode for i==0 and into the bh->b_data |
| * for i>0) and chain[i].bh points to the buffer_head of i-th indirect |
| * block for i>0 and NULL for i==0. In other words, it holds the block |
| * numbers of the chain, addresses they were taken from (and where we can |
| * verify that chain did not change) and buffer_heads hosting these |
| * numbers. |
| * |
| * Function stops when it stumbles upon zero pointer (absent block) |
| * (pointer to last triple returned, *@err == 0) |
| * or when it gets an IO error reading an indirect block |
| * (ditto, *@err == -EIO) |
| * or when it notices that chain had been changed while it was reading |
| * (ditto, *@err == -EAGAIN) |
| * or when it reads all @depth-1 indirect blocks successfully and finds |
| * the whole chain, all way to the data (returns %NULL, *err == 0). |
| */ |
| static Indirect *ext2_get_branch(struct inode *inode, |
| int depth, |
| int *offsets, |
| Indirect chain[4], |
| int *err) |
| { |
| struct super_block *sb = inode->i_sb; |
| Indirect *p = chain; |
| struct buffer_head *bh; |
| |
| *err = 0; |
| /* i_data is not going away, no lock needed */ |
| add_chain (chain, NULL, EXT2_I(inode)->i_data + *offsets); |
| if (!p->key) |
| goto no_block; |
| while (--depth) { |
| bh = sb_bread(sb, le32_to_cpu(p->key)); |
| if (!bh) |
| goto failure; |
| read_lock(&EXT2_I(inode)->i_meta_lock); |
| if (!verify_chain(chain, p)) |
| goto changed; |
| add_chain(++p, bh, (__le32*)bh->b_data + *++offsets); |
| read_unlock(&EXT2_I(inode)->i_meta_lock); |
| if (!p->key) |
| goto no_block; |
| } |
| return NULL; |
| |
| changed: |
| read_unlock(&EXT2_I(inode)->i_meta_lock); |
| brelse(bh); |
| *err = -EAGAIN; |
| goto no_block; |
| failure: |
| *err = -EIO; |
| no_block: |
| return p; |
| } |
| |
| /** |
| * ext2_find_near - find a place for allocation with sufficient locality |
| * @inode: owner |
| * @ind: descriptor of indirect block. |
| * |
| * This function returns the preferred place for block allocation. |
| * It is used when heuristic for sequential allocation fails. |
| * Rules are: |
| * + if there is a block to the left of our position - allocate near it. |
| * + if pointer will live in indirect block - allocate near that block. |
| * + if pointer will live in inode - allocate in the same cylinder group. |
| * |
| * In the latter case we colour the starting block by the callers PID to |
| * prevent it from clashing with concurrent allocations for a different inode |
| * in the same block group. The PID is used here so that functionally related |
| * files will be close-by on-disk. |
| * |
| * Caller must make sure that @ind is valid and will stay that way. |
| */ |
| |
| static ext2_fsblk_t ext2_find_near(struct inode *inode, Indirect *ind) |
| { |
| struct ext2_inode_info *ei = EXT2_I(inode); |
| __le32 *start = ind->bh ? (__le32 *) ind->bh->b_data : ei->i_data; |
| __le32 *p; |
| ext2_fsblk_t bg_start; |
| ext2_fsblk_t colour; |
| |
| /* Try to find previous block */ |
| for (p = ind->p - 1; p >= start; p--) |
| if (*p) |
| return le32_to_cpu(*p); |
| |
| /* No such thing, so let's try location of indirect block */ |
| if (ind->bh) |
| return ind->bh->b_blocknr; |
| |
| /* |
| * It is going to be referred from inode itself? OK, just put it into |
| * the same cylinder group then. |
| */ |
| bg_start = ext2_group_first_block_no(inode->i_sb, ei->i_block_group); |
| colour = (current->pid % 16) * |
| (EXT2_BLOCKS_PER_GROUP(inode->i_sb) / 16); |
| return bg_start + colour; |
| } |
| |
| /** |
| * ext2_find_goal - find a preferred place for allocation. |
| * @inode: owner |
| * @block: block we want |
| * @partial: pointer to the last triple within a chain |
| * |
| * Returns preferred place for a block (the goal). |
| */ |
| |
| static inline ext2_fsblk_t ext2_find_goal(struct inode *inode, long block, |
| Indirect *partial) |
| { |
| struct ext2_block_alloc_info *block_i; |
| |
| block_i = EXT2_I(inode)->i_block_alloc_info; |
| |
| /* |
| * try the heuristic for sequential allocation, |
| * failing that at least try to get decent locality. |
| */ |
| if (block_i && (block == block_i->last_alloc_logical_block + 1) |
| && (block_i->last_alloc_physical_block != 0)) { |
| return block_i->last_alloc_physical_block + 1; |
| } |
| |
| return ext2_find_near(inode, partial); |
| } |
| |
| /** |
| * ext2_blks_to_allocate: Look up the block map and count the number |
| * of direct blocks need to be allocated for the given branch. |
| * |
| * @branch: chain of indirect blocks |
| * @k: number of blocks need for indirect blocks |
| * @blks: number of data blocks to be mapped. |
| * @blocks_to_boundary: the offset in the indirect block |
| * |
| * return the number of direct blocks to allocate. |
| */ |
| static int |
| ext2_blks_to_allocate(Indirect * branch, int k, unsigned long blks, |
| int blocks_to_boundary) |
| { |
| unsigned long count = 0; |
| |
| /* |
| * Simple case, [t,d]Indirect block(s) has not allocated yet |
| * then it's clear blocks on that path have not allocated |
| */ |
| if (k > 0) { |
| /* right now don't hanel cross boundary allocation */ |
| if (blks < blocks_to_boundary + 1) |
| count += blks; |
| else |
| count += blocks_to_boundary + 1; |
| return count; |
| } |
| |
| count++; |
| while (count < blks && count <= blocks_to_boundary |
| && le32_to_cpu(*(branch[0].p + count)) == 0) { |
| count++; |
| } |
| return count; |
| } |
| |
| /** |
| * ext2_alloc_blocks: multiple allocate blocks needed for a branch |
| * @indirect_blks: the number of blocks need to allocate for indirect |
| * blocks |
| * @blks: the number of blocks need to allocate for direct blocks |
| * @new_blocks: on return it will store the new block numbers for |
| * the indirect blocks(if needed) and the first direct block, |
| */ |
| static int ext2_alloc_blocks(struct inode *inode, |
| ext2_fsblk_t goal, int indirect_blks, int blks, |
| ext2_fsblk_t new_blocks[4], int *err) |
| { |
| int target, i; |
| unsigned long count = 0; |
| int index = 0; |
| ext2_fsblk_t current_block = 0; |
| int ret = 0; |
| |
| /* |
| * Here we try to allocate the requested multiple blocks at once, |
| * on a best-effort basis. |
| * To build a branch, we should allocate blocks for |
| * the indirect blocks(if not allocated yet), and at least |
| * the first direct block of this branch. That's the |
| * minimum number of blocks need to allocate(required) |
| */ |
| target = blks + indirect_blks; |
| |
| while (1) { |
| count = target; |
| /* allocating blocks for indirect blocks and direct blocks */ |
| current_block = ext2_new_blocks(inode,goal,&count,err); |
| 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 |
| * @indirect_blks: depth of the chain (number of blocks to allocate) |
| * @blks: number of allocated direct blocks |
| * @goal: preferred place for allocation |
| * @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(inode); |
| 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, |
| u32 *bno, bool *new, bool *boundary, |
| int create) |
| { |
| int err; |
| 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; |
| |
| BUG_ON(maxblocks == 0); |
| |
| depth = ext2_block_to_path(inode,iblock,offsets,&blocks_to_boundary); |
| |
| if (depth == 0) |
| return -EIO; |
| |
| 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); |
| 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; |
| partial = chain + depth - 1; |
| 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); |
| goto got_it; |
| } |
| |
| if (err) { |
| mutex_unlock(&ei->truncate_mutex); |
| goto cleanup; |
| } |
| } |
| |
| /* |
| * 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 total 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 (IS_DAX(inode)) { |
| /* |
| * We must unmap blocks before zeroing so that writeback cannot |
| * overwrite zeros with stale data from block device page cache. |
| */ |
| clean_bdev_aliases(inode->i_sb->s_bdev, |
| le32_to_cpu(chain[depth-1].key), |
| count); |
| /* |
| * block must be initialised before we put it in the tree |
| * so that it's not found by another thread before it's |
| * initialised |
| */ |
| err = sb_issue_zeroout(inode->i_sb, |
| le32_to_cpu(chain[depth-1].key), count, |
| GFP_NOFS); |
| if (err) { |
| mutex_unlock(&ei->truncate_mutex); |
| goto cleanup; |
| } |
| } |
| *new = true; |
| |
| ext2_splice_branch(inode, iblock, partial, indirect_blks, count); |
| mutex_unlock(&ei->truncate_mutex); |
| got_it: |
| if (count > blocks_to_boundary) |
| *boundary = true; |
| err = count; |
| /* Clean up and exit */ |
| partial = chain + depth - 1; /* the whole chain */ |
| cleanup: |
| while (partial > chain) { |
| brelse(partial->bh); |
| partial--; |
| } |
| if (err > 0) |
| *bno = le32_to_cpu(chain[depth-1].key); |
| 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; |
| bool new = false, boundary = false; |
| u32 bno; |
| int ret; |
| |
| ret = ext2_get_blocks(inode, iblock, max_blocks, &bno, &new, &boundary, |
| create); |
| if (ret <= 0) |
| return ret; |
| |
| map_bh(bh_result, inode->i_sb, bno); |
| bh_result->b_size = (ret << inode->i_blkbits); |
| if (new) |
| set_buffer_new(bh_result); |
| if (boundary) |
| set_buffer_boundary(bh_result); |
| return 0; |
| |
| } |
| |
| static int ext2_iomap_begin(struct inode *inode, loff_t offset, loff_t length, |
| unsigned flags, struct iomap *iomap, struct iomap *srcmap) |
| { |
| unsigned int blkbits = inode->i_blkbits; |
| unsigned long first_block = offset >> blkbits; |
| unsigned long max_blocks = (length + (1 << blkbits) - 1) >> blkbits; |
| struct ext2_sb_info *sbi = EXT2_SB(inode->i_sb); |
| bool new = false, boundary = false; |
| u32 bno; |
| int ret; |
| |
| ret = ext2_get_blocks(inode, first_block, max_blocks, |
| &bno, &new, &boundary, flags & IOMAP_WRITE); |
| if (ret < 0) |
| return ret; |
| |
| iomap->flags = 0; |
| iomap->offset = (u64)first_block << blkbits; |
| if (flags & IOMAP_DAX) |
| iomap->dax_dev = sbi->s_daxdev; |
| else |
| iomap->bdev = inode->i_sb->s_bdev; |
| |
| if (ret == 0) { |
| iomap->type = IOMAP_HOLE; |
| iomap->addr = IOMAP_NULL_ADDR; |
| iomap->length = 1 << blkbits; |
| } else { |
| iomap->type = IOMAP_MAPPED; |
| iomap->addr = (u64)bno << blkbits; |
| if (flags & IOMAP_DAX) |
| iomap->addr += sbi->s_dax_part_off; |
| iomap->length = (u64)ret << blkbits; |
| iomap->flags |= IOMAP_F_MERGED; |
| } |
| |
| if (new) |
| iomap->flags |= IOMAP_F_NEW; |
| return 0; |
| } |
| |
| static int |
| ext2_iomap_end(struct inode *inode, loff_t offset, loff_t length, |
| ssize_t written, unsigned flags, struct iomap *iomap) |
| { |
| if (iomap->type == IOMAP_MAPPED && |
| written < length && |
| (flags & IOMAP_WRITE)) |
| ext2_write_failed(inode->i_mapping, offset + length); |
| return 0; |
| } |
| |
| const struct iomap_ops ext2_iomap_ops = { |
| .iomap_begin = ext2_iomap_begin, |
| .iomap_end = ext2_iomap_end, |
| }; |
| |
| int ext2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, |
| u64 start, u64 len) |
| { |
| int ret; |
| |
| inode_lock(inode); |
| len = min_t(u64, len, i_size_read(inode)); |
| ret = iomap_fiemap(inode, fieinfo, start, len, &ext2_iomap_ops); |
| inode_unlock(inode); |
| |
| return ret; |
| } |
| |
| static int ext2_writepage(struct page *page, struct writeback_control *wbc) |
| { |
| return block_write_full_page(page, ext2_get_block, wbc); |
| } |
| |
| static int ext2_read_folio(struct file *file, struct folio *folio) |
| { |
| return mpage_read_folio(folio, ext2_get_block); |
| } |
| |
| static void ext2_readahead(struct readahead_control *rac) |
| { |
| mpage_readahead(rac, ext2_get_block); |
| } |
| |
| static int |
| ext2_write_begin(struct file *file, struct address_space *mapping, |
| loff_t pos, unsigned len, struct page **pagep, void **fsdata) |
| { |
| int ret; |
| |
| ret = block_write_begin(mapping, pos, len, 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, struct page **pagep, void **fsdata) |
| { |
| int ret; |
| |
| ret = nobh_write_begin(mapping, pos, len, 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(struct kiocb *iocb, struct iov_iter *iter) |
| { |
| struct file *file = iocb->ki_filp; |
| struct address_space *mapping = file->f_mapping; |
| struct inode *inode = mapping->host; |
| size_t count = iov_iter_count(iter); |
| loff_t offset = iocb->ki_pos; |
| ssize_t ret; |
| |
| ret = blockdev_direct_IO(iocb, inode, iter, ext2_get_block); |
| if (ret < 0 && iov_iter_rw(iter) == WRITE) |
| ext2_write_failed(mapping, offset + count); |
| return ret; |
| } |
| |
| static int |
| ext2_writepages(struct address_space *mapping, struct writeback_control *wbc) |
| { |
| return mpage_writepages(mapping, wbc, ext2_get_block); |
| } |
| |
| static int |
| ext2_dax_writepages(struct address_space *mapping, struct writeback_control *wbc) |
| { |
| struct ext2_sb_info *sbi = EXT2_SB(mapping->host->i_sb); |
| |
| return dax_writeback_mapping_range(mapping, sbi->s_daxdev, wbc); |
| } |
| |
| const struct address_space_operations ext2_aops = { |
| .dirty_folio = block_dirty_folio, |
| .invalidate_folio = block_invalidate_folio, |
| .read_folio = ext2_read_folio, |
| .readahead = ext2_readahead, |
| .writepage = ext2_writepage, |
| .write_begin = ext2_write_begin, |
| .write_end = ext2_write_end, |
| .bmap = ext2_bmap, |
| .direct_IO = ext2_direct_IO, |
| .writepages = ext2_writepages, |
| .migrate_folio = buffer_migrate_folio, |
| .is_partially_uptodate = block_is_partially_uptodate, |
| .error_remove_page = generic_error_remove_page, |
| }; |
| |
| const struct address_space_operations ext2_nobh_aops = { |
| .dirty_folio = block_dirty_folio, |
| .invalidate_folio = block_invalidate_folio, |
| .read_folio = ext2_read_folio, |
| .readahead = ext2_readahead, |
| .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, |
| .migrate_folio = buffer_migrate_folio, |
| .error_remove_page = generic_error_remove_page, |
| }; |
| |
| static const struct address_space_operations ext2_dax_aops = { |
| .writepages = ext2_dax_writepages, |
| .direct_IO = noop_direct_IO, |
| .dirty_folio = noop_dirty_folio, |
| }; |
| |
| /* |
| * 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); |
| } |
| |
| /* mapping->invalidate_lock must be held when calling this function */ |
| 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); |
| |
| #ifdef CONFIG_FS_DAX |
| WARN_ON(!rwsem_is_locked(&inode->i_mapping->invalidate_lock)); |
| #endif |
| |
| 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); |
| } |
| fallthrough; |
| 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); |
| } |
| fallthrough; |
| 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); |
| } |
| break; |
| case EXT2_TIND_BLOCK: |
| ; |
| } |
| |
| ext2_discard_reservation(inode); |
| |
| mutex_unlock(&ei->truncate_mutex); |
| } |
| |
| static void ext2_truncate_blocks(struct inode *inode, loff_t offset) |
| { |
| 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; |
| |
| filemap_invalidate_lock(inode->i_mapping); |
| __ext2_truncate_blocks(inode, offset); |
| filemap_invalidate_unlock(inode->i_mapping); |
| } |
| |
| 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 (IS_DAX(inode)) { |
| error = dax_zero_range(inode, newsize, |
| PAGE_ALIGN(newsize) - newsize, NULL, |
| &ext2_iomap_ops); |
| } 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; |
| |
| filemap_invalidate_lock(inode->i_mapping); |
| truncate_setsize(inode, newsize); |
| __ext2_truncate_blocks(inode, newsize); |
| filemap_invalidate_unlock(inode->i_mapping); |
| |
| inode->i_mtime = inode->i_ctime = current_time(inode); |
| 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 | S_DAX); |
| 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; |
| if (test_opt(inode->i_sb, DAX) && S_ISREG(inode->i_mode)) |
| inode->i_flags |= S_DAX; |
| } |
| |
| void ext2_set_file_ops(struct inode *inode) |
| { |
| inode->i_op = &ext2_file_inode_operations; |
| inode->i_fop = &ext2_file_operations; |
| if (IS_DAX(inode)) |
| inode->i_mapping->a_ops = &ext2_dax_aops; |
| else if (test_opt(inode->i_sb, NOBH)) |
| inode->i_mapping->a_ops = &ext2_nobh_aops; |
| else |
| inode->i_mapping->a_ops = &ext2_aops; |
| } |
| |
| struct inode *ext2_iget (struct super_block *sb, unsigned long ino) |
| { |
| struct ext2_inode_info *ei; |
| struct buffer_head * bh = NULL; |
| 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 */ |
| 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); |
| ext2_set_inode_flags(inode); |
| 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 (ei->i_file_acl && |
| !ext2_data_block_valid(EXT2_SB(sb), ei->i_file_acl, 1)) { |
| ext2_error(sb, "ext2_iget", "bad extended attribute block %u", |
| ei->i_file_acl); |
| ret = -EFSCORRUPTED; |
| goto bad_inode; |
| } |
| |
| 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); |
| if (i_size_read(inode) < 0) { |
| ret = -EFSCORRUPTED; |
| goto bad_inode; |
| } |
| 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)) { |
| ext2_set_file_ops(inode); |
| } 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_link = (char *)ei->i_data; |
| 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; |
| inode_nohighmem(inode); |
| 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); |
| unlock_new_inode(inode); |
| return inode; |
| |
| bad_inode: |
| brelse(bh); |
| 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 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); |
| |
| 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_sync_super(sb, EXT2_SB(sb)->s_es, 1); |
| } |
| } |
| } |
| |
| 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_getattr(struct user_namespace *mnt_userns, const struct path *path, |
| struct kstat *stat, u32 request_mask, unsigned int query_flags) |
| { |
| struct inode *inode = d_inode(path->dentry); |
| struct ext2_inode_info *ei = EXT2_I(inode); |
| unsigned int flags; |
| |
| flags = ei->i_flags & EXT2_FL_USER_VISIBLE; |
| if (flags & EXT2_APPEND_FL) |
| stat->attributes |= STATX_ATTR_APPEND; |
| if (flags & EXT2_COMPR_FL) |
| stat->attributes |= STATX_ATTR_COMPRESSED; |
| if (flags & EXT2_IMMUTABLE_FL) |
| stat->attributes |= STATX_ATTR_IMMUTABLE; |
| if (flags & EXT2_NODUMP_FL) |
| stat->attributes |= STATX_ATTR_NODUMP; |
| stat->attributes_mask |= (STATX_ATTR_APPEND | |
| STATX_ATTR_COMPRESSED | |
| STATX_ATTR_ENCRYPTED | |
| STATX_ATTR_IMMUTABLE | |
| STATX_ATTR_NODUMP); |
| |
| generic_fillattr(&init_user_ns, inode, stat); |
| return 0; |
| } |
| |
| int ext2_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, |
| struct iattr *iattr) |
| { |
| struct inode *inode = d_inode(dentry); |
| int error; |
| |
| error = setattr_prepare(&init_user_ns, dentry, iattr); |
| if (error) |
| return error; |
| |
| if (is_quota_modification(inode, iattr)) { |
| error = dquot_initialize(inode); |
| if (error) |
| return error; |
| } |
| 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(&init_user_ns, inode, iattr); |
| if (iattr->ia_valid & ATTR_MODE) |
| error = posix_acl_chmod(&init_user_ns, inode, inode->i_mode); |
| mark_inode_dirty(inode); |
| |
| return error; |
| } |