diff options
Diffstat (limited to 'fs/ext2/inode.c')
| -rw-r--r-- | fs/ext2/inode.c | 1671 |
1 files changed, 1671 insertions, 0 deletions
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c new file mode 100644 index 000000000..314b415ee --- /dev/null +++ b/fs/ext2/inode.c @@ -0,0 +1,1671 @@ +// 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); + +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: Allocate multiple blocks needed for a branch. + * @inode: Owner. + * @goal: Preferred place for allocation. + * @indirect_blks: The number of blocks needed 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. + * @err: Error pointer. + * + * Return: Number of blocks allocated. + */ +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, 0); + 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_set_ctime_current(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; + bool create = flags & IOMAP_WRITE; + + /* + * For writes that could fill holes inside i_size on a + * DIO_SKIP_HOLES filesystem we forbid block creations: only + * overwrites are permitted. + */ + if ((flags & IOMAP_DIRECT) && + (first_block << blkbits) < i_size_read(inode)) + create = 0; + + /* + * Writes that span EOF might trigger an IO size update on completion, + * so consider them to be dirty for the purposes of O_DSYNC even if + * there is no other metadata changes pending or have been made here. + */ + if ((flags & IOMAP_WRITE) && offset + length > i_size_read(inode)) + iomap->flags |= IOMAP_F_DIRTY; + + ret = ext2_get_blocks(inode, first_block, max_blocks, + &bno, &new, &boundary, create); + 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) { + /* + * Switch to buffered-io for writing to holes in a non-extent + * based filesystem to avoid stale data exposure problem. + */ + if (!create && (flags & IOMAP_WRITE) && (flags & IOMAP_DIRECT)) + return -ENOTBLK; + 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) +{ + /* + * Switch to buffered-io in case of any error. + * Blocks allocated can be used by the buffered-io path. + */ + if ((flags & IOMAP_DIRECT) && (flags & IOMAP_WRITE) && written == 0) + return -ENOTBLK; + + 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_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 sector_t ext2_bmap(struct address_space *mapping, sector_t block) +{ + return generic_block_bmap(mapping,block,ext2_get_block); +} + +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, + .write_begin = ext2_write_begin, + .write_end = ext2_write_end, + .bmap = ext2_bmap, + .direct_IO = noop_direct_IO, + .writepages = ext2_writepages, + .migrate_folio = buffer_migrate_folio, + .is_partially_uptodate = block_is_partially_uptodate, + .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) +{ + ext2_fsblk_t block_to_free = 0, count = 0; + ext2_fsblk_t 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; + ext2_fsblk_t 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_truncate_page(inode, newsize, NULL, + &ext2_iomap_ops); + 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_set_ctime_current(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 + 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_set_ctime(inode, (signed)le32_to_cpu(raw_inode->i_ctime), 0); + inode->i_mtime.tv_sec = (signed)le32_to_cpu(raw_inode->i_mtime); + inode->i_atime.tv_nsec = inode->i_mtime.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; + 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); + 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_get_ctime(inode).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 mnt_idmap *idmap, 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(&nop_mnt_idmap, request_mask, inode, stat); + return 0; +} + +int ext2_setattr(struct mnt_idmap *idmap, struct dentry *dentry, + struct iattr *iattr) +{ + struct inode *inode = d_inode(dentry); + int error; + + error = setattr_prepare(&nop_mnt_idmap, dentry, iattr); + if (error) + return error; + + if (is_quota_modification(&nop_mnt_idmap, inode, iattr)) { + error = dquot_initialize(inode); + if (error) + return error; + } + if (i_uid_needs_update(&nop_mnt_idmap, iattr, inode) || + i_gid_needs_update(&nop_mnt_idmap, iattr, inode)) { + error = dquot_transfer(&nop_mnt_idmap, 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(&nop_mnt_idmap, inode, iattr); + if (iattr->ia_valid & ATTR_MODE) + error = posix_acl_chmod(&nop_mnt_idmap, dentry, inode->i_mode); + mark_inode_dirty(inode); + + return error; +} |