Re: [PATCH 01/28] ext4: xattr-in-inode support

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Wed, May 31, 2017 at 01:14:50AM -0700, Tahsin Erdogan wrote:
> From: Andreas Dilger <andreas.dilger@intel.com>
> 
> Large xattr support is implemented for EXT4_FEATURE_INCOMPAT_EA_INODE.
> 
> If the size of an xattr value is larger than will fit in a single
> external block, then the xattr value will be saved into the body
> of an external xattr inode.
> 
> The also helps support a larger number of xattr, since only the headers
> will be stored in the in-inode space or the single external block.
> 
> The inode is referenced from the xattr header via "e_value_inum",
> which was formerly "e_value_block", but that field was never used.
> The e_value_size still contains the xattr size so that listing
> xattrs does not need to look up the inode if the data is not accessed.
> 
> struct ext4_xattr_entry {
>         __u8    e_name_len;     /* length of name */
>         __u8    e_name_index;   /* attribute name index */
>         __le16  e_value_offs;   /* offset in disk block of value */
>         __le32  e_value_inum;   /* inode in which value is stored */
>         __le32  e_value_size;   /* size of attribute value */
>         __le32  e_hash;         /* hash value of name and value */
>         char    e_name[0];      /* attribute name */
> };
> 
> The xattr inode is marked with the EXT4_EA_INODE_FL flag and also
> holds a back-reference to the owning inode in its i_mtime field,
> allowing the ext4/e2fsck to verify the correct inode is accessed.

Can we store the checksum of the xattr value somewhere?  We already
checksum the values if they're stored in the ibody or a single external
block, and I'd hate to lose that protection.

We could probably reuse one of the inode fields (i_version?) for this.

--D 

> Lustre-Jira: https://jira.hpdd.intel.com/browse/LU-80
> Lustre-bugzilla: https://bugzilla.lustre.org/show_bug.cgi?id=4424
> Signed-off-by: Kalpak Shah <kalpak.shah@sun.com>
> Signed-off-by: James Simmons <uja.ornl@gmail.com>
> Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
> Signed-off-by: Tahsin Erdogan <tahsin@google.com>
> ---
>  fs/ext4/ext4.h   |  12 ++
>  fs/ext4/ialloc.c |   1 -
>  fs/ext4/inline.c |   2 +-
>  fs/ext4/inode.c  |  49 ++++-
>  fs/ext4/xattr.c  | 565 ++++++++++++++++++++++++++++++++++++++++++++++++++-----
>  fs/ext4/xattr.h  |  33 +++-
>  6 files changed, 606 insertions(+), 56 deletions(-)
> 
> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index 32191548abed..24ef56b4572f 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -1797,6 +1797,7 @@ EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
>  					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
>  					 EXT4_FEATURE_INCOMPAT_64BIT| \
>  					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
> +					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
>  					 EXT4_FEATURE_INCOMPAT_MMP | \
>  					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
>  					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
> @@ -2220,6 +2221,12 @@ struct mmpd_data {
>  #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
>  
>  /*
> + * Maximum size of xattr attributes for FEATURE_INCOMPAT_EA_INODE 1Mb
> + * This limit is arbitrary, but is reasonable for the xattr API.
> + */
> +#define EXT4_XATTR_MAX_LARGE_EA_SIZE    (1024 * 1024)
> +
> +/*
>   * Function prototypes
>   */
>  
> @@ -2231,6 +2238,10 @@ struct mmpd_data {
>  # define ATTRIB_NORET	__attribute__((noreturn))
>  # define NORET_AND	noreturn,
>  
> +struct ext4_xattr_ino_array {
> +	unsigned int xia_count;		/* # of used item in the array */
> +	unsigned int xia_inodes[0];
> +};
>  /* bitmap.c */
>  extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
>  void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
> @@ -2478,6 +2489,7 @@ extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
>  extern void ext4_set_inode_flags(struct inode *);
>  extern int ext4_alloc_da_blocks(struct inode *inode);
>  extern void ext4_set_aops(struct inode *inode);
> +extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int chunk);
>  extern int ext4_writepage_trans_blocks(struct inode *);
>  extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
>  extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
> diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
> index 98ac2f1f23b3..e2eb3cc06820 100644
> --- a/fs/ext4/ialloc.c
> +++ b/fs/ext4/ialloc.c
> @@ -294,7 +294,6 @@ void ext4_free_inode(handle_t *handle, struct inode *inode)
>  	 * as writing the quota to disk may need the lock as well.
>  	 */
>  	dquot_initialize(inode);
> -	ext4_xattr_delete_inode(handle, inode);
>  	dquot_free_inode(inode);
>  	dquot_drop(inode);
>  
> diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
> index 8d141c0c8ff9..28c5c3abddb3 100644
> --- a/fs/ext4/inline.c
> +++ b/fs/ext4/inline.c
> @@ -61,7 +61,7 @@ static int get_max_inline_xattr_value_size(struct inode *inode,
>  
>  	/* Compute min_offs. */
>  	for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
> -		if (!entry->e_value_block && entry->e_value_size) {
> +		if (!entry->e_value_inum && entry->e_value_size) {
>  			size_t offs = le16_to_cpu(entry->e_value_offs);
>  			if (offs < min_offs)
>  				min_offs = offs;
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 5cf82d03968c..e5535e5b3dc5 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -139,8 +139,6 @@ static void ext4_invalidatepage(struct page *page, unsigned int offset,
>  				unsigned int length);
>  static int __ext4_journalled_writepage(struct page *page, unsigned int len);
>  static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh);
> -static int ext4_meta_trans_blocks(struct inode *inode, int lblocks,
> -				  int pextents);
>  
>  /*
>   * Test whether an inode is a fast symlink.
> @@ -189,6 +187,8 @@ void ext4_evict_inode(struct inode *inode)
>  {
>  	handle_t *handle;
>  	int err;
> +	int extra_credits = 3;
> +	struct ext4_xattr_ino_array *lea_ino_array = NULL;
>  
>  	trace_ext4_evict_inode(inode);
>  
> @@ -238,8 +238,8 @@ void ext4_evict_inode(struct inode *inode)
>  	 * protection against it
>  	 */
>  	sb_start_intwrite(inode->i_sb);
> -	handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE,
> -				    ext4_blocks_for_truncate(inode)+3);
> +
> +	handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, extra_credits);
>  	if (IS_ERR(handle)) {
>  		ext4_std_error(inode->i_sb, PTR_ERR(handle));
>  		/*
> @@ -251,9 +251,36 @@ void ext4_evict_inode(struct inode *inode)
>  		sb_end_intwrite(inode->i_sb);
>  		goto no_delete;
>  	}
> -
>  	if (IS_SYNC(inode))
>  		ext4_handle_sync(handle);
> +
> +	/*
> +	 * Delete xattr inode before deleting the main inode.
> +	 */
> +	err = ext4_xattr_delete_inode(handle, inode, &lea_ino_array);
> +	if (err) {
> +		ext4_warning(inode->i_sb,
> +			     "couldn't delete inode's xattr (err %d)", err);
> +		goto stop_handle;
> +	}
> +
> +	if (!IS_NOQUOTA(inode))
> +		extra_credits += 2 * EXT4_QUOTA_DEL_BLOCKS(inode->i_sb);
> +
> +	if (!ext4_handle_has_enough_credits(handle,
> +			ext4_blocks_for_truncate(inode) + extra_credits)) {
> +		err = ext4_journal_extend(handle,
> +			ext4_blocks_for_truncate(inode) + extra_credits);
> +		if (err > 0)
> +			err = ext4_journal_restart(handle,
> +			ext4_blocks_for_truncate(inode) + extra_credits);
> +		if (err != 0) {
> +			ext4_warning(inode->i_sb,
> +				     "couldn't extend journal (err %d)", err);
> +			goto stop_handle;
> +		}
> +	}
> +
>  	inode->i_size = 0;
>  	err = ext4_mark_inode_dirty(handle, inode);
>  	if (err) {
> @@ -277,10 +304,10 @@ void ext4_evict_inode(struct inode *inode)
>  	 * enough credits left in the handle to remove the inode from
>  	 * the orphan list and set the dtime field.
>  	 */
> -	if (!ext4_handle_has_enough_credits(handle, 3)) {
> -		err = ext4_journal_extend(handle, 3);
> +	if (!ext4_handle_has_enough_credits(handle, extra_credits)) {
> +		err = ext4_journal_extend(handle, extra_credits);
>  		if (err > 0)
> -			err = ext4_journal_restart(handle, 3);
> +			err = ext4_journal_restart(handle, extra_credits);
>  		if (err != 0) {
>  			ext4_warning(inode->i_sb,
>  				     "couldn't extend journal (err %d)", err);
> @@ -315,8 +342,12 @@ void ext4_evict_inode(struct inode *inode)
>  		ext4_clear_inode(inode);
>  	else
>  		ext4_free_inode(handle, inode);
> +
>  	ext4_journal_stop(handle);
>  	sb_end_intwrite(inode->i_sb);
> +
> +	if (lea_ino_array != NULL)
> +		ext4_xattr_inode_array_free(inode, lea_ino_array);
>  	return;
>  no_delete:
>  	ext4_clear_inode(inode);	/* We must guarantee clearing of inode... */
> @@ -5504,7 +5535,7 @@ static int ext4_index_trans_blocks(struct inode *inode, int lblocks,
>   *
>   * Also account for superblock, inode, quota and xattr blocks
>   */
> -static int ext4_meta_trans_blocks(struct inode *inode, int lblocks,
> +int ext4_meta_trans_blocks(struct inode *inode, int lblocks,
>  				  int pextents)
>  {
>  	ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb);
> diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
> index 5d3c2536641c..444be5c7a1d5 100644
> --- a/fs/ext4/xattr.c
> +++ b/fs/ext4/xattr.c
> @@ -177,9 +177,8 @@ ext4_xattr_check_entries(struct ext4_xattr_entry *entry, void *end,
>  
>  	/* Check the values */
>  	while (!IS_LAST_ENTRY(entry)) {
> -		if (entry->e_value_block != 0)
> -			return -EFSCORRUPTED;
> -		if (entry->e_value_size != 0) {
> +		if (entry->e_value_size != 0 &&
> +		    entry->e_value_inum == 0) {
>  			u16 offs = le16_to_cpu(entry->e_value_offs);
>  			u32 size = le32_to_cpu(entry->e_value_size);
>  			void *value;
> @@ -269,6 +268,99 @@ ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index,
>  	return cmp ? -ENODATA : 0;
>  }
>  
> +/*
> + * Read the EA value from an inode.
> + */
> +static int
> +ext4_xattr_inode_read(struct inode *ea_inode, void *buf, size_t *size)
> +{
> +	unsigned long block = 0;
> +	struct buffer_head *bh = NULL;
> +	int blocksize;
> +	size_t csize, ret_size = 0;
> +
> +	if (*size == 0)
> +		return 0;
> +
> +	blocksize = ea_inode->i_sb->s_blocksize;
> +
> +	while (ret_size < *size) {
> +		csize = (*size - ret_size) > blocksize ? blocksize :
> +							*size - ret_size;
> +		bh = ext4_bread(NULL, ea_inode, block, 0);
> +		if (IS_ERR(bh)) {
> +			*size = ret_size;
> +			return PTR_ERR(bh);
> +		}
> +		memcpy(buf, bh->b_data, csize);
> +		brelse(bh);
> +
> +		buf += csize;
> +		block += 1;
> +		ret_size += csize;
> +	}
> +
> +	*size = ret_size;
> +
> +	return 0;
> +}
> +
> +struct inode *ext4_xattr_inode_iget(struct inode *parent, unsigned long ea_ino, int *err)
> +{
> +	struct inode *ea_inode = NULL;
> +
> +	ea_inode = ext4_iget(parent->i_sb, ea_ino);
> +	if (IS_ERR(ea_inode) || is_bad_inode(ea_inode)) {
> +		int rc = IS_ERR(ea_inode) ? PTR_ERR(ea_inode) : 0;
> +		ext4_error(parent->i_sb, "error while reading EA inode %lu "
> +			   "/ %d %d", ea_ino, rc, is_bad_inode(ea_inode));
> +		*err = rc != 0 ? rc : -EIO;
> +		return NULL;
> +	}
> +
> +	if (EXT4_XATTR_INODE_GET_PARENT(ea_inode) != parent->i_ino ||
> +	    ea_inode->i_generation != parent->i_generation) {
> +		ext4_error(parent->i_sb, "Backpointer from EA inode %lu "
> +			   "to parent invalid.", ea_ino);
> +		*err = -EINVAL;
> +		goto error;
> +	}
> +
> +	if (!(EXT4_I(ea_inode)->i_flags & EXT4_EA_INODE_FL)) {
> +		ext4_error(parent->i_sb, "EA inode %lu does not have "
> +			   "EXT4_EA_INODE_FL flag set.\n", ea_ino);
> +		*err = -EINVAL;
> +		goto error;
> +	}
> +
> +	*err = 0;
> +	return ea_inode;
> +
> +error:
> +	iput(ea_inode);
> +	return NULL;
> +}
> +
> +/*
> + * Read the value from the EA inode.
> + */
> +static int
> +ext4_xattr_inode_get(struct inode *inode, unsigned long ea_ino, void *buffer,
> +		     size_t *size)
> +{
> +	struct inode *ea_inode = NULL;
> +	int err;
> +
> +	ea_inode = ext4_xattr_inode_iget(inode, ea_ino, &err);
> +	if (err)
> +		return err;
> +
> +	err = ext4_xattr_inode_read(ea_inode, buffer, size);
> +	iput(ea_inode);
> +
> +	return err;
> +}
> +
>  static int
>  ext4_xattr_block_get(struct inode *inode, int name_index, const char *name,
>  		     void *buffer, size_t buffer_size)
> @@ -308,8 +400,16 @@ ext4_xattr_block_get(struct inode *inode, int name_index, const char *name,
>  		error = -ERANGE;
>  		if (size > buffer_size)
>  			goto cleanup;
> -		memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs),
> -		       size);
> +		if (entry->e_value_inum) {
> +			error = ext4_xattr_inode_get(inode,
> +					     le32_to_cpu(entry->e_value_inum),
> +					     buffer, &size);
> +			if (error)
> +				goto cleanup;
> +		} else {
> +			memcpy(buffer, bh->b_data +
> +			       le16_to_cpu(entry->e_value_offs), size);
> +		}
>  	}
>  	error = size;
>  
> @@ -350,8 +450,16 @@ ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name,
>  		error = -ERANGE;
>  		if (size > buffer_size)
>  			goto cleanup;
> -		memcpy(buffer, (void *)IFIRST(header) +
> -		       le16_to_cpu(entry->e_value_offs), size);
> +		if (entry->e_value_inum) {
> +			error = ext4_xattr_inode_get(inode,
> +					     le32_to_cpu(entry->e_value_inum),
> +					     buffer, &size);
> +			if (error)
> +				goto cleanup;
> +		} else {
> +			memcpy(buffer, (void *)IFIRST(header) +
> +			       le16_to_cpu(entry->e_value_offs), size);
> +		}
>  	}
>  	error = size;
>  
> @@ -620,7 +728,7 @@ static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last,
>  				    size_t *min_offs, void *base, int *total)
>  {
>  	for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
> -		if (last->e_value_size) {
> +		if (!last->e_value_inum && last->e_value_size) {
>  			size_t offs = le16_to_cpu(last->e_value_offs);
>  			if (offs < *min_offs)
>  				*min_offs = offs;
> @@ -631,16 +739,173 @@ static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last,
>  	return (*min_offs - ((void *)last - base) - sizeof(__u32));
>  }
>  
> -static int
> -ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s)
> +/*
> + * Write the value of the EA in an inode.
> + */
> +static int ext4_xattr_inode_write(handle_t *handle, struct inode *ea_inode,
> +				  const void *buf, int bufsize)
> +{
> +	struct buffer_head *bh = NULL;
> +	unsigned long block = 0;
> +	unsigned blocksize = ea_inode->i_sb->s_blocksize;
> +	unsigned max_blocks = (bufsize + blocksize - 1) >> ea_inode->i_blkbits;
> +	int csize, wsize = 0;
> +	int ret = 0;
> +	int retries = 0;
> +
> +retry:
> +	while (ret >= 0 && ret < max_blocks) {
> +		struct ext4_map_blocks map;
> +		map.m_lblk = block += ret;
> +		map.m_len = max_blocks -= ret;
> +
> +		ret = ext4_map_blocks(handle, ea_inode, &map,
> +				      EXT4_GET_BLOCKS_CREATE);
> +		if (ret <= 0) {
> +			ext4_mark_inode_dirty(handle, ea_inode);
> +			if (ret == -ENOSPC &&
> +			    ext4_should_retry_alloc(ea_inode->i_sb, &retries)) {
> +				ret = 0;
> +				goto retry;
> +			}
> +			break;
> +		}
> +	}
> +
> +	if (ret < 0)
> +		return ret;
> +
> +	block = 0;
> +	while (wsize < bufsize) {
> +		if (bh != NULL)
> +			brelse(bh);
> +		csize = (bufsize - wsize) > blocksize ? blocksize :
> +								bufsize - wsize;
> +		bh = ext4_getblk(handle, ea_inode, block, 0);
> +		if (IS_ERR(bh)) {
> +			ret = PTR_ERR(bh);
> +			goto out;
> +		}
> +		ret = ext4_journal_get_write_access(handle, bh);
> +		if (ret)
> +			goto out;
> +
> +		memcpy(bh->b_data, buf, csize);
> +		set_buffer_uptodate(bh);
> +		ext4_handle_dirty_metadata(handle, ea_inode, bh);
> +
> +		buf += csize;
> +		wsize += csize;
> +		block += 1;
> +	}
> +
> +	inode_lock(ea_inode);
> +	i_size_write(ea_inode, wsize);
> +	ext4_update_i_disksize(ea_inode, wsize);
> +	inode_unlock(ea_inode);
> +
> +	ext4_mark_inode_dirty(handle, ea_inode);
> +
> +out:
> +	brelse(bh);
> +
> +	return ret;
> +}
> +
> +/*
> + * Create an inode to store the value of a large EA.
> + */
> +static struct inode *ext4_xattr_inode_create(handle_t *handle,
> +					     struct inode *inode)
> +{
> +	struct inode *ea_inode = NULL;
> +
> +	/*
> +	 * Let the next inode be the goal, so we try and allocate the EA inode
> +	 * in the same group, or nearby one.
> +	 */
> +	ea_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode,
> +				  S_IFREG | 0600, NULL, inode->i_ino + 1, NULL);
> +	if (!IS_ERR(ea_inode)) {
> +		ea_inode->i_op = &ext4_file_inode_operations;
> +		ea_inode->i_fop = &ext4_file_operations;
> +		ext4_set_aops(ea_inode);
> +		ea_inode->i_generation = inode->i_generation;
> +		EXT4_I(ea_inode)->i_flags |= EXT4_EA_INODE_FL;
> +
> +		/*
> +		 * A back-pointer from EA inode to parent inode will be useful
> +		 * for e2fsck.
> +		 */
> +		EXT4_XATTR_INODE_SET_PARENT(ea_inode, inode->i_ino);
> +		unlock_new_inode(ea_inode);
> +	}
> +
> +	return ea_inode;
> +}
> +
> +/*
> + * Unlink the inode storing the value of the EA.
> + */
> +int ext4_xattr_inode_unlink(struct inode *inode, unsigned long ea_ino)
> +{
> +	struct inode *ea_inode = NULL;
> +	int err;
> +
> +	ea_inode = ext4_xattr_inode_iget(inode, ea_ino, &err);
> +	if (err)
> +		return err;
> +
> +	clear_nlink(ea_inode);
> +	iput(ea_inode);
> +
> +	return 0;
> +}
> +
> +/*
> + * Add value of the EA in an inode.
> + */
> +static int ext4_xattr_inode_set(handle_t *handle, struct inode *inode,
> +				unsigned long *ea_ino, const void *value,
> +				size_t value_len)
> +{
> +	struct inode *ea_inode;
> +	int err;
> +
> +	/* Create an inode for the EA value */
> +	ea_inode = ext4_xattr_inode_create(handle, inode);
> +	if (IS_ERR(ea_inode))
> +		return PTR_ERR(ea_inode);
> +
> +	err = ext4_xattr_inode_write(handle, ea_inode, value, value_len);
> +	if (err)
> +		clear_nlink(ea_inode);
> +	else
> +		*ea_ino = ea_inode->i_ino;
> +
> +	iput(ea_inode);
> +
> +	return err;
> +}
> +
> +static int ext4_xattr_set_entry(struct ext4_xattr_info *i,
> +				struct ext4_xattr_search *s,
> +				handle_t *handle, struct inode *inode)
>  {
>  	struct ext4_xattr_entry *last;
>  	size_t free, min_offs = s->end - s->base, name_len = strlen(i->name);
> +	int in_inode = i->in_inode;
> +	int rc;
> +
> +	if (ext4_has_feature_ea_inode(inode->i_sb) &&
> +	    (EXT4_XATTR_SIZE(i->value_len) >
> +	     EXT4_XATTR_MIN_LARGE_EA_SIZE(inode->i_sb->s_blocksize)))
> +		in_inode = 1;
>  
>  	/* Compute min_offs and last. */
>  	last = s->first;
>  	for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
> -		if (last->e_value_size) {
> +		if (!last->e_value_inum && last->e_value_size) {
>  			size_t offs = le16_to_cpu(last->e_value_offs);
>  			if (offs < min_offs)
>  				min_offs = offs;
> @@ -648,15 +913,20 @@ ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s)
>  	}
>  	free = min_offs - ((void *)last - s->base) - sizeof(__u32);
>  	if (!s->not_found) {
> -		if (s->here->e_value_size) {
> +		if (!in_inode &&
> +		    !s->here->e_value_inum && s->here->e_value_size) {
>  			size_t size = le32_to_cpu(s->here->e_value_size);
>  			free += EXT4_XATTR_SIZE(size);
>  		}
>  		free += EXT4_XATTR_LEN(name_len);
>  	}
>  	if (i->value) {
> -		if (free < EXT4_XATTR_LEN(name_len) +
> -			   EXT4_XATTR_SIZE(i->value_len))
> +		size_t value_len = EXT4_XATTR_SIZE(i->value_len);
> +
> +		if (in_inode)
> +			value_len = 0;
> +
> +		if (free < EXT4_XATTR_LEN(name_len) + value_len)
>  			return -ENOSPC;
>  	}
>  
> @@ -670,7 +940,8 @@ ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s)
>  		s->here->e_name_len = name_len;
>  		memcpy(s->here->e_name, i->name, name_len);
>  	} else {
> -		if (s->here->e_value_size) {
> +		if (!s->here->e_value_inum && s->here->e_value_size &&
> +		    s->here->e_value_offs > 0) {
>  			void *first_val = s->base + min_offs;
>  			size_t offs = le16_to_cpu(s->here->e_value_offs);
>  			void *val = s->base + offs;
> @@ -704,12 +975,18 @@ ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s)
>  			last = s->first;
>  			while (!IS_LAST_ENTRY(last)) {
>  				size_t o = le16_to_cpu(last->e_value_offs);
> -				if (last->e_value_size && o < offs)
> +				if (!last->e_value_inum &&
> +				    last->e_value_size && o < offs)
>  					last->e_value_offs =
>  						cpu_to_le16(o + size);
>  				last = EXT4_XATTR_NEXT(last);
>  			}
>  		}
> +		if (s->here->e_value_inum) {
> +			ext4_xattr_inode_unlink(inode,
> +					    le32_to_cpu(s->here->e_value_inum));
> +			s->here->e_value_inum = 0;
> +		}
>  		if (!i->value) {
>  			/* Remove the old name. */
>  			size_t size = EXT4_XATTR_LEN(name_len);
> @@ -722,11 +999,20 @@ ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s)
>  
>  	if (i->value) {
>  		/* Insert the new value. */
> -		s->here->e_value_size = cpu_to_le32(i->value_len);
> -		if (i->value_len) {
> +		if (in_inode) {
> +			unsigned long ea_ino =
> +				le32_to_cpu(s->here->e_value_inum);
> +			rc = ext4_xattr_inode_set(handle, inode, &ea_ino,
> +						  i->value, i->value_len);
> +			if (rc)
> +				goto out;
> +			s->here->e_value_inum = cpu_to_le32(ea_ino);
> +			s->here->e_value_offs = 0;
> +		} else if (i->value_len) {
>  			size_t size = EXT4_XATTR_SIZE(i->value_len);
>  			void *val = s->base + min_offs - size;
>  			s->here->e_value_offs = cpu_to_le16(min_offs - size);
> +			s->here->e_value_inum = 0;
>  			if (i->value == EXT4_ZERO_XATTR_VALUE) {
>  				memset(val, 0, size);
>  			} else {
> @@ -736,8 +1022,11 @@ ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s)
>  				memcpy(val, i->value, i->value_len);
>  			}
>  		}
> +		s->here->e_value_size = cpu_to_le32(i->value_len);
>  	}
> -	return 0;
> +
> +out:
> +	return rc;
>  }
>  
>  struct ext4_xattr_block_find {
> @@ -801,8 +1090,6 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode,
>  
>  #define header(x) ((struct ext4_xattr_header *)(x))
>  
> -	if (i->value && i->value_len > sb->s_blocksize)
> -		return -ENOSPC;
>  	if (s->base) {
>  		BUFFER_TRACE(bs->bh, "get_write_access");
>  		error = ext4_journal_get_write_access(handle, bs->bh);
> @@ -821,7 +1108,7 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode,
>  			mb_cache_entry_delete_block(ext4_mb_cache, hash,
>  						    bs->bh->b_blocknr);
>  			ea_bdebug(bs->bh, "modifying in-place");
> -			error = ext4_xattr_set_entry(i, s);
> +			error = ext4_xattr_set_entry(i, s, handle, inode);
>  			if (!error) {
>  				if (!IS_LAST_ENTRY(s->first))
>  					ext4_xattr_rehash(header(s->base),
> @@ -870,7 +1157,7 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode,
>  		s->end = s->base + sb->s_blocksize;
>  	}
>  
> -	error = ext4_xattr_set_entry(i, s);
> +	error = ext4_xattr_set_entry(i, s, handle, inode);
>  	if (error == -EFSCORRUPTED)
>  		goto bad_block;
>  	if (error)
> @@ -1070,7 +1357,7 @@ int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode,
>  
>  	if (EXT4_I(inode)->i_extra_isize == 0)
>  		return -ENOSPC;
> -	error = ext4_xattr_set_entry(i, s);
> +	error = ext4_xattr_set_entry(i, s, handle, inode);
>  	if (error) {
>  		if (error == -ENOSPC &&
>  		    ext4_has_inline_data(inode)) {
> @@ -1082,7 +1369,7 @@ int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode,
>  			error = ext4_xattr_ibody_find(inode, i, is);
>  			if (error)
>  				return error;
> -			error = ext4_xattr_set_entry(i, s);
> +			error = ext4_xattr_set_entry(i, s, handle, inode);
>  		}
>  		if (error)
>  			return error;
> @@ -1098,7 +1385,7 @@ int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode,
>  	return 0;
>  }
>  
> -static int ext4_xattr_ibody_set(struct inode *inode,
> +static int ext4_xattr_ibody_set(handle_t *handle, struct inode *inode,
>  				struct ext4_xattr_info *i,
>  				struct ext4_xattr_ibody_find *is)
>  {
> @@ -1108,7 +1395,7 @@ static int ext4_xattr_ibody_set(struct inode *inode,
>  
>  	if (EXT4_I(inode)->i_extra_isize == 0)
>  		return -ENOSPC;
> -	error = ext4_xattr_set_entry(i, s);
> +	error = ext4_xattr_set_entry(i, s, handle, inode);
>  	if (error)
>  		return error;
>  	header = IHDR(inode, ext4_raw_inode(&is->iloc));
> @@ -1155,7 +1442,7 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
>  		.name = name,
>  		.value = value,
>  		.value_len = value_len,
> -
> +		.in_inode = 0,
>  	};
>  	struct ext4_xattr_ibody_find is = {
>  		.s = { .not_found = -ENODATA, },
> @@ -1204,7 +1491,7 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
>  	}
>  	if (!value) {
>  		if (!is.s.not_found)
> -			error = ext4_xattr_ibody_set(inode, &i, &is);
> +			error = ext4_xattr_ibody_set(handle, inode, &i, &is);
>  		else if (!bs.s.not_found)
>  			error = ext4_xattr_block_set(handle, inode, &i, &bs);
>  	} else {
> @@ -1215,7 +1502,7 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
>  		if (!bs.s.not_found && ext4_xattr_value_same(&bs.s, &i))
>  			goto cleanup;
>  
> -		error = ext4_xattr_ibody_set(inode, &i, &is);
> +		error = ext4_xattr_ibody_set(handle, inode, &i, &is);
>  		if (!error && !bs.s.not_found) {
>  			i.value = NULL;
>  			error = ext4_xattr_block_set(handle, inode, &i, &bs);
> @@ -1226,11 +1513,20 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
>  					goto cleanup;
>  			}
>  			error = ext4_xattr_block_set(handle, inode, &i, &bs);
> +			if (ext4_has_feature_ea_inode(inode->i_sb) &&
> +			    error == -ENOSPC) {
> +				/* xattr not fit to block, store at external
> +				 * inode */
> +				i.in_inode = 1;
> +				error = ext4_xattr_ibody_set(handle, inode,
> +							     &i, &is);
> +			}
>  			if (error)
>  				goto cleanup;
>  			if (!is.s.not_found) {
>  				i.value = NULL;
> -				error = ext4_xattr_ibody_set(inode, &i, &is);
> +				error = ext4_xattr_ibody_set(handle, inode, &i,
> +							     &is);
>  			}
>  		}
>  	}
> @@ -1269,12 +1565,26 @@ ext4_xattr_set(struct inode *inode, int name_index, const char *name,
>  	       const void *value, size_t value_len, int flags)
>  {
>  	handle_t *handle;
> +	struct super_block *sb = inode->i_sb;
>  	int error, retries = 0;
>  	int credits = ext4_jbd2_credits_xattr(inode);
>  
>  	error = dquot_initialize(inode);
>  	if (error)
>  		return error;
> +
> +	if ((value_len >= EXT4_XATTR_MIN_LARGE_EA_SIZE(sb->s_blocksize)) &&
> +	    ext4_has_feature_ea_inode(sb)) {
> +		int nrblocks = (value_len + sb->s_blocksize - 1) >>
> +					sb->s_blocksize_bits;
> +
> +		/* For new inode */
> +		credits += EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + 3;
> +
> +		/* For data blocks of EA inode */
> +		credits += ext4_meta_trans_blocks(inode, nrblocks, 0);
> +	}
> +
>  retry:
>  	handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits);
>  	if (IS_ERR(handle)) {
> @@ -1286,7 +1596,7 @@ ext4_xattr_set(struct inode *inode, int name_index, const char *name,
>  					      value, value_len, flags);
>  		error2 = ext4_journal_stop(handle);
>  		if (error == -ENOSPC &&
> -		    ext4_should_retry_alloc(inode->i_sb, &retries))
> +		    ext4_should_retry_alloc(sb, &retries))
>  			goto retry;
>  		if (error == 0)
>  			error = error2;
> @@ -1311,7 +1621,7 @@ static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry,
>  
>  	/* Adjust the value offsets of the entries */
>  	for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
> -		if (last->e_value_size) {
> +		if (!last->e_value_inum && last->e_value_size) {
>  			new_offs = le16_to_cpu(last->e_value_offs) +
>  							value_offs_shift;
>  			last->e_value_offs = cpu_to_le16(new_offs);
> @@ -1372,7 +1682,7 @@ static int ext4_xattr_move_to_block(handle_t *handle, struct inode *inode,
>  		goto out;
>  
>  	/* Remove the chosen entry from the inode */
> -	error = ext4_xattr_ibody_set(inode, &i, is);
> +	error = ext4_xattr_ibody_set(handle, inode, &i, is);
>  	if (error)
>  		goto out;
>  
> @@ -1572,21 +1882,135 @@ int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
>  }
>  
>  
> +#define EIA_INCR 16 /* must be 2^n */
> +#define EIA_MASK (EIA_INCR - 1)
> +/* Add the large xattr @ino into @lea_ino_array for later deletion.
> + * If @lea_ino_array is new or full it will be grown and the old
> + * contents copied over.
> + */
> +static int
> +ext4_expand_ino_array(struct ext4_xattr_ino_array **lea_ino_array, __u32 ino)
> +{
> +	if (*lea_ino_array == NULL) {
> +		/*
> +		 * Start with 15 inodes, so it fits into a power-of-two size.
> +		 * If *lea_ino_array is NULL, this is essentially offsetof()
> +		 */
> +		(*lea_ino_array) =
> +			kmalloc(offsetof(struct ext4_xattr_ino_array,
> +					 xia_inodes[EIA_MASK]),
> +				GFP_NOFS);
> +		if (*lea_ino_array == NULL)
> +			return -ENOMEM;
> +		(*lea_ino_array)->xia_count = 0;
> +	} else if (((*lea_ino_array)->xia_count & EIA_MASK) == EIA_MASK) {
> +		/* expand the array once all 15 + n * 16 slots are full */
> +		struct ext4_xattr_ino_array *new_array = NULL;
> +		int count = (*lea_ino_array)->xia_count;
> +
> +		/* if new_array is NULL, this is essentially offsetof() */
> +		new_array = kmalloc(
> +				offsetof(struct ext4_xattr_ino_array,
> +					 xia_inodes[count + EIA_INCR]),
> +				GFP_NOFS);
> +		if (new_array == NULL)
> +			return -ENOMEM;
> +		memcpy(new_array, *lea_ino_array,
> +		       offsetof(struct ext4_xattr_ino_array,
> +				xia_inodes[count]));
> +		kfree(*lea_ino_array);
> +		*lea_ino_array = new_array;
> +	}
> +	(*lea_ino_array)->xia_inodes[(*lea_ino_array)->xia_count++] = ino;
> +	return 0;
> +}
> +
> +/**
> + * Add xattr inode to orphan list
> + */
> +static int
> +ext4_xattr_inode_orphan_add(handle_t *handle, struct inode *inode,
> +			int credits, struct ext4_xattr_ino_array *lea_ino_array)
> +{
> +	struct inode *ea_inode = NULL;
> +	int idx = 0, error = 0;
> +
> +	if (lea_ino_array == NULL)
> +		return 0;
> +
> +	for (; idx < lea_ino_array->xia_count; ++idx) {
> +		if (!ext4_handle_has_enough_credits(handle, credits)) {
> +			error = ext4_journal_extend(handle, credits);
> +			if (error > 0)
> +				error = ext4_journal_restart(handle, credits);
> +
> +			if (error != 0) {
> +				ext4_warning(inode->i_sb,
> +					"couldn't extend journal "
> +					"(err %d)", error);
> +				return error;
> +			}
> +		}
> +		ea_inode = ext4_xattr_inode_iget(inode,
> +				lea_ino_array->xia_inodes[idx], &error);
> +		if (error)
> +			continue;
> +		ext4_orphan_add(handle, ea_inode);
> +		/* the inode's i_count will be released by caller */
> +	}
> +
> +	return 0;
> +}
>  
>  /*
>   * ext4_xattr_delete_inode()
>   *
> - * Free extended attribute resources associated with this inode. This
> + * Free extended attribute resources associated with this inode. Traverse
> + * all entries and unlink any xattr inodes associated with this inode. This
>   * is called immediately before an inode is freed. We have exclusive
> - * access to the inode.
> + * access to the inode. If an orphan inode is deleted it will also delete any
> + * xattr block and all xattr inodes. They are checked by ext4_xattr_inode_iget()
> + * to ensure they belong to the parent inode and were not deleted already.
>   */
> -void
> -ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
> +int
> +ext4_xattr_delete_inode(handle_t *handle, struct inode *inode,
> +			struct ext4_xattr_ino_array **lea_ino_array)
>  {
>  	struct buffer_head *bh = NULL;
> +	struct ext4_xattr_ibody_header *header;
> +	struct ext4_inode *raw_inode;
> +	struct ext4_iloc iloc;
> +	struct ext4_xattr_entry *entry;
> +	int credits = 3, error = 0;
>  
> -	if (!EXT4_I(inode)->i_file_acl)
> +	if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
> +		goto delete_external_ea;
> +
> +	error = ext4_get_inode_loc(inode, &iloc);
> +	if (error)
> +		goto cleanup;
> +	raw_inode = ext4_raw_inode(&iloc);
> +	header = IHDR(inode, raw_inode);
> +	for (entry = IFIRST(header); !IS_LAST_ENTRY(entry);
> +	     entry = EXT4_XATTR_NEXT(entry)) {
> +		if (!entry->e_value_inum)
> +			continue;
> +		if (ext4_expand_ino_array(lea_ino_array,
> +					  entry->e_value_inum) != 0) {
> +			brelse(iloc.bh);
> +			goto cleanup;
> +		}
> +		entry->e_value_inum = 0;
> +	}
> +	brelse(iloc.bh);
> +
> +delete_external_ea:
> +	if (!EXT4_I(inode)->i_file_acl) {
> +		/* add xattr inode to orphan list */
> +		ext4_xattr_inode_orphan_add(handle, inode, credits,
> +						*lea_ino_array);
>  		goto cleanup;
> +	}
>  	bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
>  	if (!bh) {
>  		EXT4_ERROR_INODE(inode, "block %llu read error",
> @@ -1599,11 +2023,69 @@ ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
>  				 EXT4_I(inode)->i_file_acl);
>  		goto cleanup;
>  	}
> +
> +	for (entry = BFIRST(bh); !IS_LAST_ENTRY(entry);
> +	     entry = EXT4_XATTR_NEXT(entry)) {
> +		if (!entry->e_value_inum)
> +			continue;
> +		if (ext4_expand_ino_array(lea_ino_array,
> +					  entry->e_value_inum) != 0)
> +			goto cleanup;
> +		entry->e_value_inum = 0;
> +	}
> +
> +	/* add xattr inode to orphan list */
> +	error = ext4_xattr_inode_orphan_add(handle, inode, credits,
> +					*lea_ino_array);
> +	if (error != 0)
> +		goto cleanup;
> +
> +	if (!IS_NOQUOTA(inode))
> +		credits += 2 * EXT4_QUOTA_DEL_BLOCKS(inode->i_sb);
> +
> +	if (!ext4_handle_has_enough_credits(handle, credits)) {
> +		error = ext4_journal_extend(handle, credits);
> +		if (error > 0)
> +			error = ext4_journal_restart(handle, credits);
> +		if (error != 0) {
> +			ext4_warning(inode->i_sb,
> +				"couldn't extend journal (err %d)", error);
> +			goto cleanup;
> +		}
> +	}
> +
>  	ext4_xattr_release_block(handle, inode, bh);
>  	EXT4_I(inode)->i_file_acl = 0;
>  
>  cleanup:
>  	brelse(bh);
> +
> +	return error;
> +}
> +
> +void
> +ext4_xattr_inode_array_free(struct inode *inode,
> +			    struct ext4_xattr_ino_array *lea_ino_array)
> +{
> +	struct inode	*ea_inode = NULL;
> +	int		idx = 0;
> +	int		err;
> +
> +	if (lea_ino_array == NULL)
> +		return;
> +
> +	for (; idx < lea_ino_array->xia_count; ++idx) {
> +		ea_inode = ext4_xattr_inode_iget(inode,
> +				lea_ino_array->xia_inodes[idx], &err);
> +		if (err)
> +			continue;
> +		/* for inode's i_count get from ext4_xattr_delete_inode */
> +		if (!list_empty(&EXT4_I(ea_inode)->i_orphan))
> +			iput(ea_inode);
> +		clear_nlink(ea_inode);
> +		iput(ea_inode);
> +	}
> +	kfree(lea_ino_array);
>  }
>  
>  /*
> @@ -1655,10 +2137,9 @@ ext4_xattr_cmp(struct ext4_xattr_header *header1,
>  		    entry1->e_name_index != entry2->e_name_index ||
>  		    entry1->e_name_len != entry2->e_name_len ||
>  		    entry1->e_value_size != entry2->e_value_size ||
> +		    entry1->e_value_inum != entry2->e_value_inum ||
>  		    memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len))
>  			return 1;
> -		if (entry1->e_value_block != 0 || entry2->e_value_block != 0)
> -			return -EFSCORRUPTED;
>  		if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs),
>  			   (char *)header2 + le16_to_cpu(entry2->e_value_offs),
>  			   le32_to_cpu(entry1->e_value_size)))
> @@ -1730,7 +2211,7 @@ static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header,
>  		       *name++;
>  	}
>  
> -	if (entry->e_value_size != 0) {
> +	if (!entry->e_value_inum && entry->e_value_size) {
>  		__le32 *value = (__le32 *)((char *)header +
>  			le16_to_cpu(entry->e_value_offs));
>  		for (n = (le32_to_cpu(entry->e_value_size) +
> diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h
> index 099c8b670ef5..6e10ff9393d4 100644
> --- a/fs/ext4/xattr.h
> +++ b/fs/ext4/xattr.h
> @@ -44,7 +44,7 @@ struct ext4_xattr_entry {
>  	__u8	e_name_len;	/* length of name */
>  	__u8	e_name_index;	/* attribute name index */
>  	__le16	e_value_offs;	/* offset in disk block of value */
> -	__le32	e_value_block;	/* disk block attribute is stored on (n/i) */
> +	__le32	e_value_inum;	/* inode in which the value is stored */
>  	__le32	e_value_size;	/* size of attribute value */
>  	__le32	e_hash;		/* hash value of name and value */
>  	char	e_name[0];	/* attribute name */
> @@ -69,6 +69,26 @@ struct ext4_xattr_entry {
>  		EXT4_I(inode)->i_extra_isize))
>  #define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1))
>  
> +/*
> + * Link EA inode back to parent one using i_mtime field.
> + * Extra integer type conversion added to ignore higher
> + * bits in i_mtime.tv_sec which might be set by ext4_get()
> + */
> +#define EXT4_XATTR_INODE_SET_PARENT(inode, inum)      \
> +do {                                                  \
> +      (inode)->i_mtime.tv_sec = inum;                 \
> +} while(0)
> +
> +#define EXT4_XATTR_INODE_GET_PARENT(inode)            \
> +((__u32)(inode)->i_mtime.tv_sec)
> +
> +/*
> + * The minimum size of EA value when you start storing it in an external inode
> + * size of block - size of header - size of 1 entry - 4 null bytes
> +*/
> +#define EXT4_XATTR_MIN_LARGE_EA_SIZE(b)					\
> +	((b) - EXT4_XATTR_LEN(3) - sizeof(struct ext4_xattr_header) - 4)
> +
>  #define BHDR(bh) ((struct ext4_xattr_header *)((bh)->b_data))
>  #define ENTRY(ptr) ((struct ext4_xattr_entry *)(ptr))
>  #define BFIRST(bh) ENTRY(BHDR(bh)+1)
> @@ -77,10 +97,11 @@ struct ext4_xattr_entry {
>  #define EXT4_ZERO_XATTR_VALUE ((void *)-1)
>  
>  struct ext4_xattr_info {
> -	int name_index;
>  	const char *name;
>  	const void *value;
>  	size_t value_len;
> +	int name_index;
> +	int in_inode;
>  };
>  
>  struct ext4_xattr_search {
> @@ -140,7 +161,13 @@ extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t);
>  extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
>  extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
>  
> -extern void ext4_xattr_delete_inode(handle_t *, struct inode *);
> +extern struct inode *ext4_xattr_inode_iget(struct inode *parent, unsigned long ea_ino,
> +					   int *err);
> +extern int ext4_xattr_inode_unlink(struct inode *inode, unsigned long ea_ino);
> +extern int ext4_xattr_delete_inode(handle_t *handle, struct inode *inode,
> +				   struct ext4_xattr_ino_array **array);
> +extern void ext4_xattr_inode_array_free(struct inode *inode,
> +					struct ext4_xattr_ino_array *array);
>  
>  extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
>  			    struct ext4_inode *raw_inode, handle_t *handle);
> -- 
> 2.13.0.219.gdb65acc882-goog
>