Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1276 insertions, 0 deletions

diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
new file mode 100644
index 000000000000..b890be022496
--- /dev/null
+++ b/fs/ext2/inode.c
@@ -0,0 +1,1276 @@
+/*
+ *  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/smp_lock.h>
+#include <linux/time.h>
+#include <linux/highuid.h>
+#include <linux/pagemap.h>
+#include <linux/quotaops.h>
+#include <linux/module.h>
+#include <linux/writeback.h>
+#include <linux/buffer_head.h>
+#include <linux/mpage.h>
+#include "ext2.h"
+#include "acl.h"
+
+MODULE_AUTHOR("Remy Card and others");
+MODULE_DESCRIPTION("Second Extended Filesystem");
+MODULE_LICENSE("GPL");
+
+static int ext2_update_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);
+}
+
+/*
+ * Called at the last iput() if i_nlink is zero.
+ */
+void ext2_delete_inode (struct inode * inode)
+{
+        if (is_bad_inode(inode))
+                goto no_delete;
+        EXT2_I(inode)->i_dtime  = get_seconds();
+        mark_inode_dirty(inode);
+        ext2_update_inode(inode, inode_needs_sync(inode));
+
+        inode->i_size = 0;
+        if (inode->i_blocks)
+                ext2_truncate (inode);
+        ext2_free_inode (inode);
+
+        return;
+no_delete:
+        clear_inode(inode);     /* We must guarantee clearing of inode... */
+}
+
+void ext2_discard_prealloc (struct inode * inode)
+{
+#ifdef EXT2_PREALLOCATE
+        struct ext2_inode_info *ei = EXT2_I(inode);
+        write_lock(&ei->i_meta_lock);
+        if (ei->i_prealloc_count) {
+                unsigned short total = ei->i_prealloc_count;
+                unsigned long block = ei->i_prealloc_block;
+                ei->i_prealloc_count = 0;
+                ei->i_prealloc_block = 0;
+                write_unlock(&ei->i_meta_lock);
+                ext2_free_blocks (inode, block, total);
+                return;
+        } else
+                write_unlock(&ei->i_meta_lock);
+#endif
+}
+
+static int ext2_alloc_block (struct inode * inode, unsigned long goal, int *err)
+{
+#ifdef EXT2FS_DEBUG
+        static unsigned long alloc_hits, alloc_attempts;
+#endif
+        unsigned long result;
+
+
+#ifdef EXT2_PREALLOCATE
+        struct ext2_inode_info *ei = EXT2_I(inode);
+        write_lock(&ei->i_meta_lock);
+        if (ei->i_prealloc_count &&
+            (goal == ei->i_prealloc_block || goal + 1 == ei->i_prealloc_block))
+        {
+                result = ei->i_prealloc_block++;
+                ei->i_prealloc_count--;
+                write_unlock(&ei->i_meta_lock);
+                ext2_debug ("preallocation hit (%lu/%lu).\n",
+                            ++alloc_hits, ++alloc_attempts);
+        } else {
+                write_unlock(&ei->i_meta_lock);
+                ext2_discard_prealloc (inode);
+                ext2_debug ("preallocation miss (%lu/%lu).\n",
+                            alloc_hits, ++alloc_attempts);
+                if (S_ISREG(inode->i_mode))
+                        result = ext2_new_block (inode, goal, 
+                                 &ei->i_prealloc_count,
+                                 &ei->i_prealloc_block, err);
+                else
+                        result = ext2_new_block(inode, goal, NULL, NULL, err);
+        }
+#else
+        result = ext2_new_block (inode, goal, 0, 0, err);
+#endif
+        return result;
+}
+
+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_warning (inode->i_sb, "ext2_block_to_path", "block < 0");
+        } 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_warning (inode->i_sb, "ext2_block_to_path", "block > big");
+        }
+        if (boundary)
+                *boundary = (i_block & (ptrs - 1)) == (final - 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 prefered 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 unsigned long 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;
+        unsigned long bg_start;
+        unsigned long 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 refered from inode itself? OK, just put it into
+         * the same cylinder group then.
+         */
+        bg_start = (ei->i_block_group * EXT2_BLOCKS_PER_GROUP(inode->i_sb)) +
+                le32_to_cpu(EXT2_SB(inode->i_sb)->s_es->s_first_data_block);
+        colour = (current->pid % 16) *
+                        (EXT2_BLOCKS_PER_GROUP(inode->i_sb) / 16);
+        return bg_start + colour;
+}
+
+/**
+ *      ext2_find_goal - find a prefered place for allocation.
+ *      @inode: owner
+ *      @block:  block we want
+ *      @chain:  chain of indirect blocks
+ *      @partial: pointer to the last triple within a chain
+ *      @goal:  place to store the result.
+ *
+ *      Normally this function find the prefered place for block allocation,
+ *      stores it in *@goal and returns zero. If the branch had been changed
+ *      under us we return -EAGAIN.
+ */
+
+static inline int ext2_find_goal(struct inode *inode,
+                                 long block,
+                                 Indirect chain[4],
+                                 Indirect *partial,
+                                 unsigned long *goal)
+{
+        struct ext2_inode_info *ei = EXT2_I(inode);
+        write_lock(&ei->i_meta_lock);
+        if ((block == ei->i_next_alloc_block + 1) && ei->i_next_alloc_goal) {
+                ei->i_next_alloc_block++;
+                ei->i_next_alloc_goal++;
+        } 
+        if (verify_chain(chain, partial)) {
+                /*
+                 * try the heuristic for sequential allocation,
+                 * failing that at least try to get decent locality.
+                 */
+                if (block == ei->i_next_alloc_block)
+                        *goal = ei->i_next_alloc_goal;
+                if (!*goal)
+                        *goal = ext2_find_near(inode, partial);
+                write_unlock(&ei->i_meta_lock);
+                return 0;
+        }
+        write_unlock(&ei->i_meta_lock);
+        return -EAGAIN;
+}
+
+/**
+ *      ext2_alloc_branch - allocate and set up a chain of blocks.
+ *      @inode: owner
+ *      @num: depth of the chain (number of blocks to allocate)
+ *      @offsets: offsets (in the blocks) to store the pointers to next.
+ *      @branch: place to store the chain in.
+ *
+ *      This function allocates @num blocks, zeroes out all but the last one,
+ *      links them into chain and (if we are synchronous) writes them to disk.
+ *      In other words, it prepares a branch that can be spliced onto the
+ *      inode. It stores the information about that chain in the branch[], in
+ *      the same format as ext2_get_branch() would do. We are calling it after
+ *      we had read the existing part of chain and partial points to the last
+ *      triple of that (one with zero ->key). Upon the exit we have the same
+ *      picture as after the successful ext2_get_block(), excpet 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 num,
+                             unsigned long goal,
+                             int *offsets,
+                             Indirect *branch)
+{
+        int blocksize = inode->i_sb->s_blocksize;
+        int n = 0;
+        int err;
+        int i;
+        int parent = ext2_alloc_block(inode, goal, &err);
+
+        branch[0].key = cpu_to_le32(parent);
+        if (parent) for (n = 1; n < num; n++) {
+                struct buffer_head *bh;
+                /* Allocate the next block */
+                int nr = ext2_alloc_block(inode, parent, &err);
+                if (!nr)
+                        break;
+                branch[n].key = cpu_to_le32(nr);
+                /*
+                 * 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, parent);
+                lock_buffer(bh);
+                memset(bh->b_data, 0, blocksize);
+                branch[n].bh = bh;
+                branch[n].p = (__le32 *) bh->b_data + offsets[n];
+                *branch[n].p = branch[n].key;
+                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_osync_inode()
+                 * and b_inode_buffers.  But not for directories.
+                 */
+                if (S_ISDIR(inode->i_mode) && IS_DIRSYNC(inode))
+                        sync_dirty_buffer(bh);
+                parent = nr;
+        }
+        if (n == num)
+                return 0;
+
+        /* Allocation failed, free what we already allocated */
+        for (i = 1; i < n; i++)
+                bforget(branch[i].bh);
+        for (i = 0; i < n; i++)
+                ext2_free_blocks(inode, le32_to_cpu(branch[i].key), 1);
+        return err;
+}
+
+/**
+ *      ext2_splice_branch - splice the allocated branch onto inode.
+ *      @inode: owner
+ *      @block: (logical) number of block we are adding
+ *      @chain: chain of indirect blocks (with a missing link - see
+ *              ext2_alloc_branch)
+ *      @where: location of missing link
+ *      @num:   number of blocks we are adding
+ *
+ *      This function verifies that chain (up to the missing link) had not
+ *      changed, 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. Otherwise (== chain had been changed)
+ *      we free the new blocks (forgetting their buffer_heads, indeed) and
+ *      return -EAGAIN.
+ */
+
+static inline int ext2_splice_branch(struct inode *inode,
+                                     long block,
+                                     Indirect chain[4],
+                                     Indirect *where,
+                                     int num)
+{
+        struct ext2_inode_info *ei = EXT2_I(inode);
+        int i;
+
+        /* Verify that place we are splicing to is still there and vacant */
+
+        write_lock(&ei->i_meta_lock);
+        if (!verify_chain(chain, where-1) || *where->p)
+                goto changed;
+
+        /* That's it */
+
+        *where->p = where->key;
+        ei->i_next_alloc_block = block;
+        ei->i_next_alloc_goal = le32_to_cpu(where[num-1].key);
+
+        write_unlock(&ei->i_meta_lock);
+
+        /* We are done with atomic stuff, now do the rest of housekeeping */
+
+        inode->i_ctime = CURRENT_TIME_SEC;
+
+        /* had we spliced it onto indirect block? */
+        if (where->bh)
+                mark_buffer_dirty_inode(where->bh, inode);
+
+        mark_inode_dirty(inode);
+        return 0;
+
+changed:
+        write_unlock(&ei->i_meta_lock);
+        for (i = 1; i < num; i++)
+                bforget(where[i].bh);
+        for (i = 0; i < num; i++)
+                ext2_free_blocks(inode, le32_to_cpu(where[i].key), 1);
+        return -EAGAIN;
+}
+
+/*
+ * 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.
+ */
+
+int ext2_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create)
+{
+        int err = -EIO;
+        int offsets[4];
+        Indirect chain[4];
+        Indirect *partial;
+        unsigned long goal;
+        int left;
+        int boundary = 0;
+        int depth = ext2_block_to_path(inode, iblock, offsets, &boundary);
+
+        if (depth == 0)
+                goto out;
+
+reread:
+        partial = ext2_get_branch(inode, depth, offsets, chain, &err);
+
+        /* Simplest case - block found, no allocation needed */
+        if (!partial) {
+got_it:
+                map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key));
+                if (boundary)
+                        set_buffer_boundary(bh_result);
+                /* Clean up and exit */
+                partial = chain+depth-1; /* the whole chain */
+                goto cleanup;
+        }
+
+        /* Next simple case - plain lookup or failed read of indirect block */
+        if (!create || err == -EIO) {
+cleanup:
+                while (partial > chain) {
+                        brelse(partial->bh);
+                        partial--;
+                }
+out:
+                return err;
+        }
+
+        /*
+         * Indirect block might be removed by truncate while we were
+         * reading it. Handling of that case (forget what we've got and
+         * reread) is taken out of the main path.
+         */
+        if (err == -EAGAIN)
+                goto changed;
+
+        goal = 0;
+        if (ext2_find_goal(inode, iblock, chain, partial, &goal) < 0)
+                goto changed;
+
+        left = (chain + depth) - partial;
+        err = ext2_alloc_branch(inode, left, goal,
+                                        offsets+(partial-chain), partial);
+        if (err)
+                goto cleanup;
+
+        if (ext2_splice_branch(inode, iblock, chain, partial, left) < 0)
+                goto changed;
+
+        set_buffer_new(bh_result);
+        goto got_it;
+
+changed:
+        while (partial > chain) {
+                brelse(partial->bh);
+                partial--;
+        }
+        goto reread;
+}
+
+static int ext2_writepage(struct page *page, struct writeback_control *wbc)
+{
+        return block_write_full_page(page, ext2_get_block, wbc);
+}
+
+static int ext2_readpage(struct file *file, struct page *page)
+{
+        return mpage_readpage(page, ext2_get_block);
+}
+
+static int
+ext2_readpages(struct file *file, struct address_space *mapping,
+                struct list_head *pages, unsigned nr_pages)
+{
+        return mpage_readpages(mapping, pages, nr_pages, ext2_get_block);
+}
+
+static int
+ext2_prepare_write(struct file *file, struct page *page,
+                        unsigned from, unsigned to)
+{
+        return block_prepare_write(page,from,to,ext2_get_block);
+}
+
+static int
+ext2_nobh_prepare_write(struct file *file, struct page *page,
+                        unsigned from, unsigned to)
+{
+        return nobh_prepare_write(page,from,to,ext2_get_block);
+}
+
+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 int
+ext2_get_blocks(struct inode *inode, sector_t iblock, unsigned long max_blocks,
+                        struct buffer_head *bh_result, int create)
+{
+        int ret;
+
+        ret = ext2_get_block(inode, iblock, bh_result, create);
+        if (ret == 0)
+                bh_result->b_size = (1 << inode->i_blkbits);
+        return ret;
+}
+
+static ssize_t
+ext2_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
+                        loff_t offset, unsigned long nr_segs)
+{
+        struct file *file = iocb->ki_filp;
+        struct inode *inode = file->f_mapping->host;
+
+        return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
+                                offset, nr_segs, ext2_get_blocks, NULL);
+}
+
+static int
+ext2_writepages(struct address_space *mapping, struct writeback_control *wbc)
+{
+        return mpage_writepages(mapping, wbc, ext2_get_block);
+}
+
+struct address_space_operations ext2_aops = {
+        .readpage               = ext2_readpage,
+        .readpages              = ext2_readpages,
+        .writepage              = ext2_writepage,
+        .sync_page              = block_sync_page,
+        .prepare_write          = ext2_prepare_write,
+        .commit_write           = generic_commit_write,
+        .bmap                   = ext2_bmap,
+        .direct_IO              = ext2_direct_IO,
+        .writepages             = ext2_writepages,
+};
+
+struct address_space_operations ext2_nobh_aops = {
+        .readpage               = ext2_readpage,
+        .readpages              = ext2_readpages,
+        .writepage              = ext2_nobh_writepage,
+        .sync_page              = block_sync_page,
+        .prepare_write          = ext2_nobh_prepare_write,
+        .commit_write           = nobh_commit_write,
+        .bmap                   = ext2_bmap,
+        .direct_IO              = ext2_direct_IO,
+        .writepages             = ext2_writepages,
+};
+
+/*
+ * 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 refered 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 refered 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 {
+                                mark_inode_dirty(inode);
+                                ext2_free_blocks (inode, block_to_free, count);
+                        free_this:
+                                block_to_free = nr;
+                                count = 1;
+                        }
+                }
+        }
+        if (count > 0) {
+                mark_inode_dirty(inode);
+                ext2_free_blocks (inode, block_to_free, count);
+        }
+}
+
+/**
+ *      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 refered 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);
+}
+
+void ext2_truncate (struct inode * inode)
+{
+        __le32 *i_data = EXT2_I(inode)->i_data;
+        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;
+
+        if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+            S_ISLNK(inode->i_mode)))
+                return;
+        if (ext2_inode_is_fast_symlink(inode))
+                return;
+        if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+                return;
+
+        ext2_discard_prealloc(inode);
+
+        blocksize = inode->i_sb->s_blocksize;
+        iblock = (inode->i_size + blocksize-1)
+                                        >> EXT2_BLOCK_SIZE_BITS(inode->i_sb);
+
+        if (test_opt(inode->i_sb, NOBH))
+                nobh_truncate_page(inode->i_mapping, inode->i_size);
+        else
+                block_truncate_page(inode->i_mapping,
+                                inode->i_size, ext2_get_block);
+
+        n = ext2_block_to_path(inode, iblock, offsets, NULL);
+        if (n == 0)
+                return;
+
+        if (n == 1) {
+                ext2_free_data(inode, i_data+offsets[0],
+                                        i_data + EXT2_NDIR_BLOCKS);
+                goto do_indirects;
+        }
+
+        partial = ext2_find_shared(inode, n, offsets, chain, &nr);
+        /* Kill the top of shared branch (already detached) */
+        if (nr) {
+                if (partial == chain)
+                        mark_inode_dirty(inode);
+                else
+                        mark_buffer_dirty_inode(partial->bh, inode);
+                ext2_free_branches(inode, &nr, &nr+1, (chain+n-1) - partial);
+        }
+        /* Clear the ends of indirect blocks on the shared branch */
+        while (partial > chain) {
+                ext2_free_branches(inode,
+                                   partial->p + 1,
+                                   (__le32*)partial->bh->b_data+addr_per_block,
+                                   (chain+n-1) - partial);
+                mark_buffer_dirty_inode(partial->bh, inode);
+                brelse (partial->bh);
+                partial--;
+        }
+do_indirects:
+        /* Kill the remaining (whole) subtrees */
+        switch (offsets[0]) {
+                default:
+                        nr = i_data[EXT2_IND_BLOCK];
+                        if (nr) {
+                                i_data[EXT2_IND_BLOCK] = 0;
+                                mark_inode_dirty(inode);
+                                ext2_free_branches(inode, &nr, &nr+1, 1);
+                        }
+                case EXT2_IND_BLOCK:
+                        nr = i_data[EXT2_DIND_BLOCK];
+                        if (nr) {
+                                i_data[EXT2_DIND_BLOCK] = 0;
+                                mark_inode_dirty(inode);
+                                ext2_free_branches(inode, &nr, &nr+1, 2);
+                        }
+                case EXT2_DIND_BLOCK:
+                        nr = i_data[EXT2_TIND_BLOCK];
+                        if (nr) {
+                                i_data[EXT2_TIND_BLOCK] = 0;
+                                mark_inode_dirty(inode);
+                                ext2_free_branches(inode, &nr, &nr+1, 3);
+                        }
+                case EXT2_TIND_BLOCK:
+                        ;
+        }
+        inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
+        if (inode_needs_sync(inode)) {
+                sync_mapping_buffers(inode->i_mapping);
+                ext2_sync_inode (inode);
+        } else {
+                mark_inode_dirty(inode);
+        }
+}
+
+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, &bh);
+        if (!gdp)
+                goto Egdp;
+        /*
+         * Figure out the offset within the block group inode table
+         */
+        offset = ((ino - 1) % EXT2_INODES_PER_GROUP(sb)) * EXT2_INODE_SIZE(sb);
+        block = le32_to_cpu(gdp->bg_inode_table) +
+                (offset >> EXT2_BLOCK_SIZE_BITS(sb));
+        if (!(bh = sb_bread(sb, block)))
+                goto Eio;
+
+        *p = bh;
+        offset &= (EXT2_BLOCK_SIZE(sb) - 1);
+        return (struct ext2_inode *) (bh->b_data + offset);
+
+Einval:
+        ext2_error(sb, "ext2_get_inode", "bad inode number: %lu",
+                   (unsigned long) ino);
+        return ERR_PTR(-EINVAL);
+Eio:
+        ext2_error(sb, "ext2_get_inode",
+                   "unable to read inode block - inode=%lu, block=%lu",
+                   (unsigned long) ino, block);
+Egdp:
+        return ERR_PTR(-EIO);
+}
+
+void ext2_set_inode_flags(struct inode *inode)
+{
+        unsigned int flags = EXT2_I(inode)->i_flags;
+
+        inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
+        if (flags & EXT2_SYNC_FL)
+                inode->i_flags |= S_SYNC;
+        if (flags & EXT2_APPEND_FL)
+                inode->i_flags |= S_APPEND;
+        if (flags & EXT2_IMMUTABLE_FL)
+                inode->i_flags |= S_IMMUTABLE;
+        if (flags & EXT2_NOATIME_FL)
+                inode->i_flags |= S_NOATIME;
+        if (flags & EXT2_DIRSYNC_FL)
+                inode->i_flags |= S_DIRSYNC;
+}
+
+void ext2_read_inode (struct inode * inode)
+{
+        struct ext2_inode_info *ei = EXT2_I(inode);
+        ino_t ino = inode->i_ino;
+        struct buffer_head * bh;
+        struct ext2_inode * raw_inode = ext2_get_inode(inode->i_sb, ino, &bh);
+        int n;
+
+#ifdef CONFIG_EXT2_FS_POSIX_ACL
+        ei->i_acl = EXT2_ACL_NOT_CACHED;
+        ei->i_default_acl = EXT2_ACL_NOT_CACHED;
+#endif
+        if (IS_ERR(raw_inode))
+                goto bad_inode;
+
+        inode->i_mode = le16_to_cpu(raw_inode->i_mode);
+        inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
+        inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
+        if (!(test_opt (inode->i_sb, NO_UID32))) {
+                inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
+                inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
+        }
+        inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
+        inode->i_size = le32_to_cpu(raw_inode->i_size);
+        inode->i_atime.tv_sec = le32_to_cpu(raw_inode->i_atime);
+        inode->i_ctime.tv_sec = le32_to_cpu(raw_inode->i_ctime);
+        inode->i_mtime.tv_sec = le32_to_cpu(raw_inode->i_mtime);
+        inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = 0;
+        ei->i_dtime = le32_to_cpu(raw_inode->i_dtime);
+        /* We now have enough fields to check if the inode was active or not.
+         * This is needed because nfsd might try to access dead inodes
+         * the test is that same one that e2fsck uses
+         * NeilBrown 1999oct15
+         */
+        if (inode->i_nlink == 0 && (inode->i_mode == 0 || ei->i_dtime)) {
+                /* this inode is deleted */
+                brelse (bh);
+                goto bad_inode;
+        }
+        inode->i_blksize = PAGE_SIZE;   /* This is the optimal IO size (for stat), not the fs block size */
+        inode->i_blocks = le32_to_cpu(raw_inode->i_blocks);
+        ei->i_flags = le32_to_cpu(raw_inode->i_flags);
+        ei->i_faddr = le32_to_cpu(raw_inode->i_faddr);
+        ei->i_frag_no = raw_inode->i_frag;
+        ei->i_frag_size = raw_inode->i_fsize;
+        ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
+        ei->i_dir_acl = 0;
+        if (S_ISREG(inode->i_mode))
+                inode->i_size |= ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32;
+        else
+                ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl);
+        ei->i_dtime = 0;
+        inode->i_generation = le32_to_cpu(raw_inode->i_generation);
+        ei->i_state = 0;
+        ei->i_next_alloc_block = 0;
+        ei->i_next_alloc_goal = 0;
+        ei->i_prealloc_count = 0;
+        ei->i_block_group = (ino - 1) / EXT2_INODES_PER_GROUP(inode->i_sb);
+        ei->i_dir_start_lookup = 0;
+
+        /*
+         * NOTE! The in-memory inode i_data array is in little-endian order
+         * even on big-endian machines: we do NOT byteswap the block numbers!
+         */
+        for (n = 0; n < EXT2_N_BLOCKS; n++)
+                ei->i_data[n] = raw_inode->i_block[n];
+
+        if (S_ISREG(inode->i_mode)) {
+                inode->i_op = &ext2_file_inode_operations;
+                inode->i_fop = &ext2_file_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_ISDIR(inode->i_mode)) {
+                inode->i_op = &ext2_dir_inode_operations;
+                inode->i_fop = &ext2_dir_operations;
+                if (test_opt(inode->i_sb, NOBH))
+                        inode->i_mapping->a_ops = &ext2_nobh_aops;
+                else
+                        inode->i_mapping->a_ops = &ext2_aops;
+        } else if (S_ISLNK(inode->i_mode)) {
+                if (ext2_inode_is_fast_symlink(inode))
+                        inode->i_op = &ext2_fast_symlink_inode_operations;
+                else {
+                        inode->i_op = &ext2_symlink_inode_operations;
+                        if (test_opt(inode->i_sb, NOBH))
+                                inode->i_mapping->a_ops = &ext2_nobh_aops;
+                        else
+                                inode->i_mapping->a_ops = &ext2_aops;
+                }
+        } else {
+                inode->i_op = &ext2_special_inode_operations;
+                if (raw_inode->i_block[0])
+                        init_special_inode(inode, inode->i_mode,
+                           old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
+                else 
+                        init_special_inode(inode, inode->i_mode,
+                           new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
+        }
+        brelse (bh);
+        ext2_set_inode_flags(inode);
+        return;
+        
+bad_inode:
+        make_bad_inode(inode);
+        return;
+}
+
+static int ext2_update_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 = inode->i_uid;
+        gid_t gid = inode->i_gid;
+        struct buffer_head * bh;
+        struct ext2_inode * raw_inode = ext2_get_inode(sb, ino, &bh);
+        int n;
+        int err = 0;
+
+        if (IS_ERR(raw_inode))
+                return -EIO;
+
+        /* For fields not not tracking in the in-memory inode,
+         * initialise them to zero for new inodes. */
+        if (ei->i_state & EXT2_STATE_NEW)
+                memset(raw_inode, 0, EXT2_SB(sb)->s_inode_size);
+
+        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.
+                                */
+                                lock_kernel();
+                                ext2_update_dynamic_rev(sb);
+                                EXT2_SET_RO_COMPAT_FEATURE(sb,
+                                        EXT2_FEATURE_RO_COMPAT_LARGE_FILE);
+                                unlock_kernel();
+                                ext2_write_super(sb);
+                        }
+                }
+        }
+        
+        raw_inode->i_generation = cpu_to_le32(inode->i_generation);
+        if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
+                if (old_valid_dev(inode->i_rdev)) {
+                        raw_inode->i_block[0] =
+                                cpu_to_le32(old_encode_dev(inode->i_rdev));
+                        raw_inode->i_block[1] = 0;
+                } else {
+                        raw_inode->i_block[0] = 0;
+                        raw_inode->i_block[1] =
+                                cpu_to_le32(new_encode_dev(inode->i_rdev));
+                        raw_inode->i_block[2] = 0;
+                }
+        } else for (n = 0; n < EXT2_N_BLOCKS; n++)
+                raw_inode->i_block[n] = ei->i_data[n];
+        mark_buffer_dirty(bh);
+        if (do_sync) {
+                sync_dirty_buffer(bh);
+                if (buffer_req(bh) && !buffer_uptodate(bh)) {
+                        printk ("IO error syncing ext2 inode [%s:%08lx]\n",
+                                sb->s_id, (unsigned long) ino);
+                        err = -EIO;
+                }
+        }
+        ei->i_state &= ~EXT2_STATE_NEW;
+        brelse (bh);
+        return err;
+}
+
+int ext2_write_inode(struct inode *inode, int wait)
+{
+        return ext2_update_inode(inode, wait);
+}
+
+int ext2_sync_inode(struct inode *inode)
+{
+        struct writeback_control wbc = {
+                .sync_mode = WB_SYNC_ALL,
+                .nr_to_write = 0,       /* sys_fsync did this */
+        };
+        return sync_inode(inode, &wbc);
+}
+
+int ext2_setattr(struct dentry *dentry, struct iattr *iattr)
+{
+        struct inode *inode = dentry->d_inode;
+        int error;
+
+        error = inode_change_ok(inode, iattr);
+        if (error)
+                return error;
+        if ((iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) ||
+            (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid)) {
+                error = DQUOT_TRANSFER(inode, iattr) ? -EDQUOT : 0;
+                if (error)
+                        return error;
+        }
+        error = inode_setattr(inode, iattr);
+        if (!error && (iattr->ia_valid & ATTR_MODE))
+                error = ext2_acl_chmod(inode);
+        return error;
+}