Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c0fba368 authored by Alex Elder's avatar Alex Elder Committed by Sage Weil
Browse files

rbd: have rbd_dev_image_id() set format 1 image id 



Currently, rbd_dev_probe() assumes that any error returned by
rbd_dev_image_id() is most likely -ENOENT, and responds by
calling the format 1 probe routine, rbd_dev_v1_probe().  Then,
at the top of rbd_dev_v1_probe(), an empty string is allocated
for the image id.

This is sort of unbalanced.  Fix this by having rbd_dev_image_id()
look for -ENOENT from its "get_id" method call.  If that is seen,
have it allocate the empty string there rather than depending on
rbd_dev_v1_probe() to do it.

Given that this is effectively defining the format of the image,
set rbd_dev->image_format inside rbd_dev_image_id() rather than in
the format-specific probe routines.

Also drop a redundant hunk of code in rbd_dev_image_id().

Signed-off-by: default avatarAlex Elder <elder@inktank.com>
Reviewed-by: default avatarJosh Durgin <josh.durgin@inktank.com>
parent a0cab924

drivers/block/rbd.c

+32 −30
Original line number Diff line number Diff line
@@ -4477,20 +4477,19 @@ static int rbd_dev_image_id(struct rbd_device *rbd_dev) 
	size_t size;

	char *object_name;

	void *response;

	void *p;



	/* If we already have it we don't need to look it up */



	if (rbd_dev->spec->image_id)

		return 0;

	char *image_id;



	/*

	 * When probing a parent image, the image id is already

	 * known (and the image name likely is not).  There's no

	 * need to fetch the image id again in this case.

	 * need to fetch the image id again in this case.  We

	 * do still need to set the image format though.

	 */

	if (rbd_dev->spec->image_id)

	if (rbd_dev->spec->image_id) {

		rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;



		return 0;

	}



	/*

	 * First, see if the format 2 image id file exists, and if
@@ -4512,24 +4511,32 @@ static int rbd_dev_image_id(struct rbd_device *rbd_dev) 
		goto out;

	}



	/* If it doesn't exist we'll assume it's a format 1 image */



	ret = rbd_obj_method_sync(rbd_dev, object_name,

				"rbd", "get_id", NULL, 0,

				response, RBD_IMAGE_ID_LEN_MAX, NULL);

	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);

	if (ret < 0)

		goto out;

	if (ret == -ENOENT) {

		image_id = kstrdup("", GFP_KERNEL);

		ret = image_id ? 0 : -ENOMEM;

		if (!ret)

			rbd_dev->image_format = 1;

	} else if (ret > sizeof (__le32)) {

		void *p = response;



	p = response;

	rbd_dev->spec->image_id = ceph_extract_encoded_string(&p,

						p + ret,

		image_id = ceph_extract_encoded_string(&p, p + ret,

						NULL, GFP_NOIO);

	ret = 0;



	if (IS_ERR(rbd_dev->spec->image_id)) {

		ret = PTR_ERR(rbd_dev->spec->image_id);

		rbd_dev->spec->image_id = NULL;

		ret = IS_ERR(image_id) ? PTR_ERR(image_id) : 0;

		if (!ret)

			rbd_dev->image_format = 2;

	} else {

		dout("image_id is %s\n", rbd_dev->spec->image_id);

		ret = -EINVAL;

	}



	if (!ret) {

		rbd_dev->spec->image_id = image_id;

		dout("image_id is %s\n", image_id);

	}

out:

	kfree(response);
@@ -4543,12 +4550,6 @@ static int rbd_dev_v1_probe(struct rbd_device *rbd_dev) 
	int ret;

	size_t size;



	/* Version 1 images have no id; empty string is used */



	rbd_dev->spec->image_id = kstrdup("", GFP_KERNEL);

	if (!rbd_dev->spec->image_id)

		return -ENOMEM;



	/* Record the header object name for this rbd image. */



	size = strlen(rbd_dev->spec->image_name) + sizeof (RBD_SUFFIX);
@@ -4571,8 +4572,6 @@ static int rbd_dev_v1_probe(struct rbd_device *rbd_dev) 
	rbd_dev->parent_spec = NULL;

	rbd_dev->parent_overlap = 0;



	rbd_dev->image_format = 1;



	dout("discovered version 1 image, header name is %s\n",

		rbd_dev->header_name);
@@ -4651,8 +4650,6 @@ static int rbd_dev_v2_probe(struct rbd_device *rbd_dev) 
		goto out_err;

	rbd_dev->header.obj_version = ver;



	rbd_dev->image_format = 2;



	dout("discovered version 2 image, header name is %s\n",

		rbd_dev->header_name);
@@ -4795,6 +4792,11 @@ static int rbd_dev_probe(struct rbd_device *rbd_dev) 
	 */

	ret = rbd_dev_image_id(rbd_dev);

	if (ret)

		return ret;

	rbd_assert(rbd_dev->spec->image_id);

	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));



	if (rbd_dev->image_format == 1)

		ret = rbd_dev_v1_probe(rbd_dev);

	else

		ret = rbd_dev_v2_probe(rbd_dev);