Commit 02afca6c authored by Alex Elder's avatar Alex Elder Committed by Sage Weil
Browse files

libceph: isolate message page field manipulation 

Define a function ceph_msg_data_set_pages(), which more clearly
abstracts the assignment page-related fields for data in a ceph
message structure.  Use this new function in the osd client and mds
client.

Ideally, these fields would never be set more than once (with
BUG_ON() calls to guarantee that).  At the moment though the osd
client sets these every time it receives a message, and in the event
of a communication problem this can happen more than once.  (This
will be resolved shortly, but setting up these helpers first makes
it all a bit easier to work with.)

Rearrange the field order in a ceph_msg structure to group those
that are used to define the possible data payloads.

This partially resolves:
    http://tracker.ceph.com/issues/4263



Signed-off-by: default avatarAlex Elder <elder@inktank.com>
Reviewed-by: default avatarJosh Durgin <josh.durgin@inktank.com>
parent e0c59487

fs/ceph/mds_client.c

+2 −2
Original line number Diff line number Diff line
@@ -1721,8 +1721,8 @@ static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc, 
	msg->front.iov_len = p - msg->front.iov_base;

	msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);



	msg->pages = req->r_pages;

	msg->page_count = req->r_num_pages;

	ceph_msg_data_set_pages(msg, req->r_pages, req->r_num_pages, 0);



	msg->hdr.data_len = cpu_to_le32(req->r_data_len);

	msg->hdr.data_off = cpu_to_le16(0);

include/linux/ceph/messenger.h

+13 −9
Original line number Diff line number Diff line
@@ -74,21 +74,22 @@ struct ceph_msg { 
	struct ceph_msg_footer footer;	/* footer */

	struct kvec front;              /* unaligned blobs of message */

	struct ceph_buffer *middle;



	struct page **pages;		/* data payload.  NOT OWNER. */

	unsigned page_count;		/* size of page array */

	unsigned page_alignment;        /* io offset in first page */

	unsigned int page_alignment;	/* io offset in first page */

	unsigned int page_count;	/* # pages in array or list */

	struct ceph_pagelist *pagelist; /* instead of pages */



	struct ceph_connection *con;

	struct list_head list_head;



	struct kref kref;

#ifdef CONFIG_BLOCK

	unsigned int bio_seg;		/* current bio segment */

	struct bio  *bio;		/* instead of pages/pagelist */

	struct bio  *bio_iter;		/* bio iterator */

	unsigned int bio_seg;		/* current bio segment */

#endif /* CONFIG_BLOCK */

	struct ceph_pagelist *trail;	/* the trailing part of the data */



	struct ceph_connection *con;

	struct list_head list_head;	/* links for connection lists */



	struct kref kref;

	bool front_is_vmalloc;

	bool more_to_follow;

	bool needs_out_seq;
@@ -218,6 +219,9 @@ extern void ceph_msg_revoke_incoming(struct ceph_msg *msg); 


extern void ceph_con_keepalive(struct ceph_connection *con);



extern void ceph_msg_data_set_pages(struct ceph_msg *msg, struct page **pages,

				unsigned int page_count, size_t alignment);



extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags,

				     bool can_fail);

extern void ceph_msg_kfree(struct ceph_msg *m);

net/ceph/messenger.c

+11 −0
Original line number Diff line number Diff line
@@ -2689,6 +2689,17 @@ void ceph_con_keepalive(struct ceph_connection *con) 
}

EXPORT_SYMBOL(ceph_con_keepalive);



void ceph_msg_data_set_pages(struct ceph_msg *msg, struct page **pages,

		unsigned int page_count, size_t alignment)

{

	/* BUG_ON(msg->pages); */

	/* BUG_ON(msg->page_count); */



	msg->pages = pages;

	msg->page_count = page_count;

	msg->page_alignment = alignment & ~PAGE_MASK;

}

EXPORT_SYMBOL(ceph_msg_data_set_pages);



/*

 * construct a new message with given type, size

net/ceph/osd_client.c

+4 −6
Original line number Diff line number Diff line
@@ -1760,11 +1760,10 @@ int ceph_osdc_start_request(struct ceph_osd_client *osdc, 
	if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGES) {

		unsigned int page_count;



		req->r_request->pages = osd_data->pages;

		page_count = calc_pages_for((u64)osd_data->alignment,

						(u64)osd_data->length);

		req->r_request->page_count = page_count;

		req->r_request->page_alignment = osd_data->alignment;

		ceph_msg_data_set_pages(req->r_request, osd_data->pages,

			page_count, osd_data->alignment);

#ifdef CONFIG_BLOCK

	} else if (osd_data->type == CEPH_OSD_DATA_TYPE_BIO) {

		req->r_request->bio = osd_data->bio;
@@ -2135,9 +2134,8 @@ static struct ceph_msg *get_reply(struct ceph_connection *con, 
			}

			page_count = calc_pages_for((u64)osd_data->alignment,

							(u64)osd_data->length);

			m->pages = osd_data->pages;

			m->page_count = page_count;

			m->page_alignment = osd_data->alignment;

			ceph_msg_data_set_pages(m, osd_data->pages,

				osd_data->num_pages, osd_data->alignment);

#ifdef CONFIG_BLOCK

		} else if (osd_data->type == CEPH_OSD_DATA_TYPE_BIO) {

			m->bio = osd_data->bio;

CRA Git | Maintained and supported by SUSTech CRA and CCSE