Commit 30999ad0 authored by Linus Torvalds's avatar Linus Torvalds
Browse files
Pull orangefs updates from Mike Marshall:
 "Fixes:
   - validate getxattr response length
   - don't overflow the bufmap slot on readahead
   - fix parsing problem with kernel debug keywords

  Cleanup:
   - take better advantage of strscpy

  New:
   - manage bufmap as folios
   - add usercopy whitelist to orangefs_op_cache"

* tag 'for-linus-7.1-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
  bufmap: manage as folios, V2.
  orangefs: validate getxattr response length
  orangefs_readahead: don't overflow the bufmap slot.
  debugfs: take better advantage of strscpy.
  orangefs: add usercopy whitelist to orangefs_op_cache
  orangefs-debugfs.c: fix parsing problem with kernel debug keywords.
parents cdd4dc3a e61bc5e4
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+27 −9
Original line number Diff line number Diff line
@@ -224,6 +224,8 @@ static void orangefs_readahead(struct readahead_control *rac)
	loff_t new_start = readahead_pos(rac);
	int ret;
	size_t new_len = 0;
	size_t this_size;
	size_t remaining;

	loff_t bytes_remaining = inode->i_size - readahead_pos(rac);
	loff_t pages_remaining = bytes_remaining / PAGE_SIZE;
@@ -239,17 +241,33 @@ static void orangefs_readahead(struct readahead_control *rac)
	offset = readahead_pos(rac);
	i_pages = &rac->mapping->i_pages;

	iov_iter_xarray(&iter, ITER_DEST, i_pages, offset, readahead_length(rac));
	iov_iter_xarray(&iter, ITER_DEST, i_pages,
				offset, readahead_length(rac));

	remaining = readahead_length(rac);
	while (remaining) {
		if (remaining > 4194304)
			this_size = 4194304;
		else
			this_size = remaining;

		/* read in the pages. */
		if ((ret = wait_for_direct_io(ORANGEFS_IO_READ, inode,
			&offset, &iter, readahead_length(rac),
			inode->i_size, NULL, NULL, rac->file)) < 0)
				&offset, &iter, this_size,
				inode->i_size, NULL, NULL, rac->file)) < 0) {
			gossip_debug(GOSSIP_FILE_DEBUG,
			"%s: wait_for_direct_io failed. \n", __func__);
	else
				"%s: wait_for_direct_io failed. :%d: \n",
				__func__, ret);
			goto cleanup;
		} else {
			ret = 0;
		}

		remaining -= this_size;
		offset += this_size;
	}

cleanup:
	/* clean up. */
	while ((folio = readahead_folio(rac))) {
		if (!ret)
+358 −43
Original line number Diff line number Diff line
@@ -139,9 +139,15 @@ static int get(struct slot_map *m)
/* used to describe mapped buffers */
struct orangefs_bufmap_desc {
	void __user *uaddr;		/* user space address pointer */
	struct page **page_array;	/* array of mapped pages */
	int array_count;		/* size of above arrays */
	struct list_head list_link;
	struct folio **folio_array;
	/*
	 * folio_offsets could be needed when userspace sets custom
	 * sizes in user_desc, or when folios aren't all backed by
	 * 2MB THPs.
	 */
	size_t *folio_offsets;
	int folio_count;
	bool is_two_2mib_chunks;
};

static struct orangefs_bufmap {
@@ -150,8 +156,10 @@ static struct orangefs_bufmap {
	int desc_count;
	int total_size;
	int page_count;
	int folio_count;

	struct page **page_array;
	struct folio **folio_array;
	struct orangefs_bufmap_desc *desc_array;

	/* array to track usage of buffer descriptors */
@@ -174,6 +182,17 @@ orangefs_bufmap_unmap(struct orangefs_bufmap *bufmap)
static void
orangefs_bufmap_free(struct orangefs_bufmap *bufmap)
{
	int i;

	if (!bufmap)
		return;

	for (i = 0; i < bufmap->desc_count; i++) {
		kfree(bufmap->desc_array[i].folio_array);
		kfree(bufmap->desc_array[i].folio_offsets);
		bufmap->desc_array[i].folio_array = NULL;
		bufmap->desc_array[i].folio_offsets = NULL;
	}
	kfree(bufmap->page_array);
	kfree(bufmap->desc_array);
	bitmap_free(bufmap->buffer_index_array);
@@ -213,8 +232,10 @@ orangefs_bufmap_alloc(struct ORANGEFS_dev_map_desc *user_desc)
	bufmap->desc_count = user_desc->count;
	bufmap->desc_size = user_desc->size;
	bufmap->desc_shift = ilog2(bufmap->desc_size);
	bufmap->page_count = bufmap->total_size / PAGE_SIZE;

	bufmap->buffer_index_array = bitmap_zalloc(bufmap->desc_count, GFP_KERNEL);
	bufmap->buffer_index_array =
		bitmap_zalloc(bufmap->desc_count, GFP_KERNEL);
	if (!bufmap->buffer_index_array)
		goto out_free_bufmap;

@@ -223,16 +244,21 @@ orangefs_bufmap_alloc(struct ORANGEFS_dev_map_desc *user_desc)
	if (!bufmap->desc_array)
		goto out_free_index_array;

	bufmap->page_count = bufmap->total_size / PAGE_SIZE;

	/* allocate storage to track our page mappings */
	bufmap->page_array =
		kzalloc_objs(struct page *, bufmap->page_count);
	if (!bufmap->page_array)
		goto out_free_desc_array;

	/* allocate folio array. */
	bufmap->folio_array = kzalloc_objs(struct folio *, bufmap->page_count);
	if (!bufmap->folio_array)
		goto out_free_page_array;

	return bufmap;

out_free_page_array:
	kfree(bufmap->page_array);
out_free_desc_array:
	kfree(bufmap->desc_array);
out_free_index_array:
@@ -243,16 +269,65 @@ orangefs_bufmap_alloc(struct ORANGEFS_dev_map_desc *user_desc)
	return NULL;
}

static int
orangefs_bufmap_map(struct orangefs_bufmap *bufmap,
static int orangefs_bufmap_group_folios(struct orangefs_bufmap *bufmap)
{
	int i = 0;
	int f = 0;
	int k;
	int num_pages;
	struct page *page;
	struct folio *folio;

	while (i < bufmap->page_count) {
		page = bufmap->page_array[i];
		folio = page_folio(page);
		num_pages = folio_nr_pages(folio);
		gossip_debug(GOSSIP_BUFMAP_DEBUG,
			"%s: i:%d: num_pages:%d: \n", __func__, i, num_pages);

		for (k = 1; k < num_pages; k++) {
			if (bufmap->page_array[i + k] != folio_page(folio, k)) {
				gossip_err("%s: bad match,  i:%d: k:%d:\n",
					__func__, i, k);
				return -EINVAL;
			}
		}

		bufmap->folio_array[f++] = folio;
		i += num_pages;
	}

	bufmap->folio_count = f;
	pr_info("%s: Grouped %d folios from %d pages.\n",
		__func__,
		bufmap->folio_count,
		bufmap->page_count);
	return 0;
}

static int orangefs_bufmap_map(struct orangefs_bufmap *bufmap,
				struct ORANGEFS_dev_map_desc *user_desc)
{
	int pages_per_desc = bufmap->desc_size / PAGE_SIZE;
	int offset = 0, ret, i;
	int ret;
	int i;
	int j;
	int current_folio;
	int desc_pages_needed;
	int desc_folio_count;
	int remaining_pages;
	int need_avail_min;
	int pages_assigned_to_this_desc;
	int allocated_descs = 0;
	size_t current_offset;
	size_t adjust_offset;
	struct folio *folio;

	/* map the pages */
	ret = pin_user_pages_fast((unsigned long)user_desc->ptr,
			     bufmap->page_count, FOLL_WRITE, bufmap->page_array);
		bufmap->page_count,
		FOLL_WRITE,
		bufmap->page_array);

	if (ret < 0)
		return ret;
@@ -260,7 +335,6 @@ orangefs_bufmap_map(struct orangefs_bufmap *bufmap,
	if (ret != bufmap->page_count) {
		gossip_err("orangefs error: asked for %d pages, only got %d.\n",
				bufmap->page_count, ret);

		for (i = 0; i < ret; i++)
			unpin_user_page(bufmap->page_array[i]);
		return -ENOMEM;
@@ -275,16 +349,120 @@ orangefs_bufmap_map(struct orangefs_bufmap *bufmap,
	for (i = 0; i < bufmap->page_count; i++)
		flush_dcache_page(bufmap->page_array[i]);

	/* build a list of available descriptors */
	for (offset = 0, i = 0; i < bufmap->desc_count; i++) {
		bufmap->desc_array[i].page_array = &bufmap->page_array[offset];
		bufmap->desc_array[i].array_count = pages_per_desc;
	/*
	 * Group pages into folios.
	 */
	ret = orangefs_bufmap_group_folios(bufmap);
	if (ret)
		goto unpin;

	pr_info("%s: desc_size=%d bytes (%d pages per desc), total folios=%d\n",
			__func__, bufmap->desc_size, pages_per_desc,
			bufmap->folio_count);

	current_folio = 0;
	remaining_pages = 0;
	current_offset = 0;
	for (i = 0; i < bufmap->desc_count; i++) {
		desc_pages_needed = pages_per_desc;
		desc_folio_count = 0;
		pages_assigned_to_this_desc = 0;
		bufmap->desc_array[i].is_two_2mib_chunks = false;

		/*
		 * We hope there was enough memory that each desc is
		 * covered by two THPs/folios, if not we want to keep on
		 * working even if there's only one page per folio.
		 */
		bufmap->desc_array[i].folio_array =
			kzalloc_objs(struct folio *, pages_per_desc);
		if (!bufmap->desc_array[i].folio_array) {
			ret = -ENOMEM;
			goto unpin;
		}

		bufmap->desc_array[i].folio_offsets =
			kzalloc_objs(size_t, pages_per_desc);
		if (!bufmap->desc_array[i].folio_offsets) {
			ret = -ENOMEM;
			kfree(bufmap->desc_array[i].folio_array);
			bufmap->desc_array[i].folio_array = NULL;
			goto unpin;
		}

		bufmap->desc_array[i].uaddr =
		    (user_desc->ptr + (i * pages_per_desc * PAGE_SIZE));
		offset += pages_per_desc;
			user_desc->ptr + (size_t)i * bufmap->desc_size;

		/*
		 * Accumulate folios until desc is full.
		 */
		while (desc_pages_needed > 0) {
			if (remaining_pages == 0) {
				/* shouldn't happen. */
				if (current_folio >= bufmap->folio_count) {
					ret = -EINVAL;
					goto unpin;
				}
				folio = bufmap->folio_array[current_folio++];
				remaining_pages = folio_nr_pages(folio);
				current_offset = 0;
			} else {
				folio = bufmap->folio_array[current_folio - 1];
			}

			need_avail_min =
				min(desc_pages_needed, remaining_pages);
			adjust_offset = need_avail_min * PAGE_SIZE;

			bufmap->desc_array[i].folio_array[desc_folio_count] =
				folio;
			bufmap->desc_array[i].folio_offsets[desc_folio_count] =
				current_offset;
			desc_folio_count++;
			pages_assigned_to_this_desc += need_avail_min;
			desc_pages_needed -= need_avail_min;
			remaining_pages -= need_avail_min;
			current_offset += adjust_offset;
		}

		/* Detect optimal case: two 2MiB folios per 4MiB slot. */
		if (desc_folio_count == 2 &&
		  folio_nr_pages(bufmap->desc_array[i].folio_array[0]) == 512 &&
		  folio_nr_pages(bufmap->desc_array[i].folio_array[1]) == 512) {
			bufmap->desc_array[i].is_two_2mib_chunks = true;
			gossip_debug(GOSSIP_BUFMAP_DEBUG, "%s: descriptor :%d: "
				"optimal folio/page ratio.\n", __func__, i);
		}

		bufmap->desc_array[i].folio_count = desc_folio_count;
		gossip_debug(GOSSIP_BUFMAP_DEBUG,
			" descriptor %d: folio_count=%d, "
			"pages_assigned=%d (should be %d)\n",
			i, desc_folio_count, pages_assigned_to_this_desc,
			pages_per_desc);

		allocated_descs = i + 1;
	}

	return 0;
unpin:
	/*
	 * rollback any allocations we got so far...
	 * Memory pressure, like in generic/340, led me
	 * to write the rollback this way.
	 */
	for (j = 0; j < allocated_descs; j++) {
		if (bufmap->desc_array[j].folio_array) {
			kfree(bufmap->desc_array[j].folio_array);
			bufmap->desc_array[j].folio_array = NULL;
		}
		if (bufmap->desc_array[j].folio_offsets) {
			kfree(bufmap->desc_array[j].folio_offsets);
			bufmap->desc_array[j].folio_offsets = NULL;
		}
	}
	unpin_user_pages(bufmap->page_array, bufmap->page_count);
	return ret;
}

/*
@@ -292,6 +470,8 @@ orangefs_bufmap_map(struct orangefs_bufmap *bufmap,
 *
 * initializes the mapped buffer interface
 *
 * user_desc is the parameters provided by userspace for the bufmap.
 *
 * returns 0 on success, -errno on failure
 */
int orangefs_bufmap_initialize(struct ORANGEFS_dev_map_desc *user_desc)
@@ -300,8 +480,8 @@ int orangefs_bufmap_initialize(struct ORANGEFS_dev_map_desc *user_desc)
	int ret = -EINVAL;

	gossip_debug(GOSSIP_BUFMAP_DEBUG,
		     "orangefs_bufmap_initialize: called (ptr ("
		     "%p) sz (%d) cnt(%d).\n",
		     "%s: called (ptr (" "%p) sz (%d) cnt(%d).\n",
		     __func__,
		     user_desc->ptr,
		     user_desc->size,
		     user_desc->count);
@@ -371,7 +551,7 @@ int orangefs_bufmap_initialize(struct ORANGEFS_dev_map_desc *user_desc)
	spin_unlock(&orangefs_bufmap_lock);

	gossip_debug(GOSSIP_BUFMAP_DEBUG,
		     "orangefs_bufmap_initialize: exiting normally\n");
		     "%s: exiting normally\n", __func__);
	return 0;

out_unmap_bufmap:
@@ -471,22 +651,89 @@ int orangefs_bufmap_copy_from_iovec(struct iov_iter *iter,
				size_t size)
{
	struct orangefs_bufmap_desc *to;
	int i;
	size_t remaining = size;
	int folio_index = 0;
	struct folio *folio;
	size_t folio_offset;
	size_t folio_avail;
	size_t copy_amount;
	size_t copied;
	void *kaddr;
	size_t half;
	size_t first;
	size_t second;

	to = &__orangefs_bufmap->desc_array[buffer_index];

	/* shouldn't happen... */
	if (size > 4194304)
		pr_info("%s: size:%zu\n", __func__, size);

	gossip_debug(GOSSIP_BUFMAP_DEBUG,
		     "%s: buffer_index:%d: size:%zu:\n",
		     __func__, buffer_index, size);
		"%s: buffer_index:%d size:%zu folio_count:%d\n",
		__func__,
		buffer_index,
		size,
		to->folio_count);

	/* Fast path: exactly two 2 MiB folios */
	if (to->is_two_2mib_chunks && size <= 4194304) {
		gossip_debug(GOSSIP_BUFMAP_DEBUG,
			"%s: fastpath hit.\n", __func__);
		half = 2097152;		/* 2 MiB */
		first = min(size, half);
		second = (size > half) ? size - half : 0;

		/* First 2 MiB chunk */
		kaddr = kmap_local_folio(to->folio_array[0], 0);
		copied = copy_from_iter(kaddr, first, iter);
		kunmap_local(kaddr);
		if (copied != first)
			return -EFAULT;

	to = &__orangefs_bufmap->desc_array[buffer_index];
	for (i = 0; size; i++) {
		struct page *page = to->page_array[i];
		size_t n = size;
		if (n > PAGE_SIZE)
			n = PAGE_SIZE;
		if (copy_page_from_iter(page, 0, n, iter) != n)
		if (second == 0)
			return 0;

		/* Second 2 MiB chunk */
		kaddr = kmap_local_folio(to->folio_array[1], 0);
		copied = copy_from_iter(kaddr, second, iter);
		kunmap_local(kaddr);
		if (copied != second)
			return -EFAULT;

		return 0;
	}

	while (remaining > 0) {

		if (unlikely(folio_index >= to->folio_count ||
			to->folio_array[folio_index] == NULL)) {
				gossip_err("%s: "
				   "folio_index:%d: >= folio_count:%d: "
		                   "(size %zu, buffer %d)\n",
					__func__,
					folio_index,
					to->folio_count,
					size,
					buffer_index);
				return -EFAULT;
		size -= n;
		}

		folio = to->folio_array[folio_index];
		folio_offset = to->folio_offsets[folio_index];
		folio_avail = folio_nr_pages(folio) * PAGE_SIZE - folio_offset;
		copy_amount = min(remaining, folio_avail);
		kaddr = kmap_local_folio(folio, folio_offset);
		copied = copy_from_iter(kaddr, copy_amount, iter);
		kunmap_local(kaddr);

		if (copied != copy_amount)
			return -EFAULT;

		remaining -= copied;
		folio_index++;
	}

	return 0;
}

@@ -499,23 +746,91 @@ int orangefs_bufmap_copy_to_iovec(struct iov_iter *iter,
				    size_t size)
{
	struct orangefs_bufmap_desc *from;
	int i;
	size_t remaining = size;
	int folio_index = 0;
	struct folio *folio;
	size_t folio_offset;
	size_t folio_avail;
	size_t copy_amount;
	size_t copied;
	void *kaddr;
	size_t half;
	size_t first;
	size_t second;

	from = &__orangefs_bufmap->desc_array[buffer_index];

	/* shouldn't happen... */
	if (size > 4194304)
		pr_info("%s: size:%zu\n", __func__, size);

	gossip_debug(GOSSIP_BUFMAP_DEBUG,
		"%s: buffer_index:%d size:%zu folio_count:%d\n",
		__func__,
		buffer_index,
		size,
		from->folio_count);

	/* Fast path: exactly two 2 MiB folios */
	if (from->is_two_2mib_chunks && size <= 4194304) {
		gossip_debug(GOSSIP_BUFMAP_DEBUG,
		     "%s: buffer_index:%d: size:%zu:\n",
		     __func__, buffer_index, size);
			"%s: fastpath hit.\n", __func__);
		half = 2097152;		/* 2 MiB */
		first = min(size, half);
		second = (size > half) ? size - half : 0;
		void *kaddr;
		size_t copied;

		/* First 2 MiB chunk */
		kaddr = kmap_local_folio(from->folio_array[0], 0);
		copied = copy_to_iter(kaddr, first, iter);
		kunmap_local(kaddr);
		if (copied != first)
			return -EFAULT;

		if (second == 0)
			return 0;

	for (i = 0; size; i++) {
		struct page *page = from->page_array[i];
		size_t n = size;
		if (n > PAGE_SIZE)
			n = PAGE_SIZE;
		n = copy_page_to_iter(page, 0, n, iter);
		if (!n)
		/* Second 2 MiB chunk */
		kaddr = kmap_local_folio(from->folio_array[1], 0);
		copied = copy_to_iter(kaddr, second, iter);
		kunmap_local(kaddr);
		if (copied != second)
			return -EFAULT;
		size -= n;

		return 0;
	}

	while (remaining > 0) {

		if (unlikely(folio_index >= from->folio_count ||
			from->folio_array[folio_index] == NULL)) {
				gossip_err("%s: "
				   "folio_index:%d: >= folio_count:%d: "
		                   "(size %zu, buffer %d)\n",
					__func__,
					folio_index,
					from->folio_count,
					size,
					buffer_index);
				return -EFAULT;
		}

		folio = from->folio_array[folio_index];
		folio_offset = from->folio_offsets[folio_index];
		folio_avail = folio_nr_pages(folio) * PAGE_SIZE - folio_offset;
		copy_amount = min(remaining, folio_avail);

		kaddr = kmap_local_folio(folio, folio_offset);
		copied = copy_to_iter(kaddr, copy_amount, iter);
		kunmap_local(kaddr);

		if (copied != copy_amount)
			return -EFAULT;

		remaining -= copied;
		folio_index++;
	}

	return 0;
}
+5 −1
Original line number Diff line number Diff line
@@ -19,10 +19,14 @@ static struct kmem_cache *op_cache;

int op_cache_initialize(void)
{
	op_cache = kmem_cache_create("orangefs_op_cache",
	op_cache = kmem_cache_create_usercopy("orangefs_op_cache",
				     sizeof(struct orangefs_kernel_op_s),
				     0,
				     0,
					 offsetof(struct orangefs_kernel_op_s, tag),
					 offsetof(struct orangefs_kernel_op_s, upcall) +
					     sizeof(struct orangefs_upcall_s) -
						 offsetof(struct orangefs_kernel_op_s, tag),
				     NULL);

	if (!op_cache) {
+17 −20
Original line number Diff line number Diff line
@@ -238,12 +238,10 @@ void orangefs_debugfs_init(int debug_mask)
static void orangefs_kernel_debug_init(void)
{
	static char k_buffer[ORANGEFS_MAX_DEBUG_STRING_LEN] = { };
	size_t len = strlen(kernel_debug_string);
	size_t len =
		strscpy(k_buffer, kernel_debug_string, sizeof(k_buffer) - 1);

	gossip_debug(GOSSIP_DEBUGFS_DEBUG, "%s: start\n", __func__);

	if (len + 1 < ORANGEFS_MAX_DEBUG_STRING_LEN) {
		memcpy(k_buffer, kernel_debug_string, len);
	if (len > 0) {
		k_buffer[len] = '\n';
		k_buffer[len + 1] = '\0';
	} else {
@@ -339,12 +337,10 @@ static int help_show(struct seq_file *m, void *v)
static void orangefs_client_debug_init(void)
{
	static char c_buffer[ORANGEFS_MAX_DEBUG_STRING_LEN] = { };
	size_t len = strlen(client_debug_string);

	gossip_debug(GOSSIP_DEBUGFS_DEBUG, "%s: start\n", __func__);
	size_t len =
		strscpy(c_buffer, client_debug_string, sizeof(c_buffer) - 1);

	if (len + 1 < ORANGEFS_MAX_DEBUG_STRING_LEN) {
		memcpy(c_buffer, client_debug_string, len);
	if (len > 0) {
		c_buffer[len] = '\n';
		c_buffer[len + 1] = '\0';
	} else {
@@ -443,7 +439,7 @@ static ssize_t orangefs_debug_write(struct file *file,
		count = ORANGEFS_MAX_DEBUG_STRING_LEN;
	}

	buf = memdup_user_nul(ubuf, count - 1);
	buf = memdup_user_nul(ubuf, count);
	if (IS_ERR(buf)) {
		gossip_debug(GOSSIP_DEBUGFS_DEBUG,
			     "%s: memdup_user_nul failed!\n",
@@ -452,6 +448,7 @@ static ssize_t orangefs_debug_write(struct file *file,
		buf = NULL;
		goto out;
	}
	strim(buf);

	/*
	 * Map the keyword string from userspace into a valid debug mask.
@@ -873,9 +870,10 @@ static int check_amalgam_keyword(void *mask, int type)
 */
static void debug_string_to_mask(char *debug_string, void *mask, int type)
{
	char *unchecked_keyword;
	int i;
	char *strsep_fodder = kstrdup(debug_string, GFP_KERNEL);
	char *trimmed;
	char *token;
	char *original_pointer;
	int element_count = 0;
	struct client_debug_mask *c_mask = NULL;
@@ -893,17 +891,16 @@ static void debug_string_to_mask(char *debug_string, void *mask, int type)
	}

	original_pointer = strsep_fodder;
	while ((unchecked_keyword = strsep(&strsep_fodder, ",")))
		if (strlen(unchecked_keyword)) {
	while ((token = strsep(&strsep_fodder, ",")) != NULL) {
		trimmed = strim(token);
		if (*trimmed) {
			for (i = 0; i < element_count; i++)
				if (type)
					do_c_mask(i,
						  unchecked_keyword,
						  &c_mask);
					do_c_mask(i, trimmed, &c_mask);
				else
					do_k_mask(i,
						  unchecked_keyword,
						  &k_mask);
					do_k_mask(i, trimmed, &k_mask);

		}
	}

	kfree(original_pointer);
+4 −0
Original line number Diff line number Diff line
@@ -188,6 +188,10 @@ ssize_t orangefs_inode_getxattr(struct inode *inode, const char *name,
	 * Length returned includes null terminator.
	 */
	length = new_op->downcall.resp.getxattr.val_sz;
	if (length < 0 || length > ORANGEFS_MAX_XATTR_VALUELEN) {
		ret = -EIO;
		goto out_release_op;
	}

	/*
	 * Just return the length of the queried attribute.