mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-05 03:44:03 +08:00
abfa034e4b
* remove lot of update to different data structure * add a seperate callback for zero copy request. * above makes non zero copy code path simpler * remove conditionalizing TREAD/TREADDIR/TWRITE in the zero copy path * Fix the dotu p9_check_errors with zero copy. Add sufficient doc around * Add support for both in and output buffers in zero copy callback * pin and unpin pages in the same context * use helpers instead of defining page offset and rest of page ourself * Fix mem leak in p9_check_errors * Remove 'E' and 'F' in p9pdu_vwritef Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
70 lines
2.0 KiB
C
70 lines
2.0 KiB
C
/*
|
|
* Copyright IBM Corporation, 2010
|
|
* Author Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of version 2.1 of the GNU Lesser General Public License
|
|
* as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it would be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
|
|
*
|
|
*/
|
|
|
|
#include <linux/slab.h>
|
|
#include <linux/module.h>
|
|
#include <net/9p/9p.h>
|
|
#include <net/9p/client.h>
|
|
#include <linux/scatterlist.h>
|
|
#include "trans_common.h"
|
|
|
|
/**
|
|
* p9_release_req_pages - Release pages after the transaction.
|
|
*/
|
|
void p9_release_pages(struct page **pages, int nr_pages)
|
|
{
|
|
int i = 0;
|
|
while (pages[i] && nr_pages--) {
|
|
put_page(pages[i]);
|
|
i++;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(p9_release_pages);
|
|
|
|
/**
|
|
* p9_nr_pages - Return number of pages needed to accommodate the payload.
|
|
*/
|
|
int p9_nr_pages(char *data, int len)
|
|
{
|
|
unsigned long start_page, end_page;
|
|
start_page = (unsigned long)data >> PAGE_SHIFT;
|
|
end_page = ((unsigned long)data + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
|
|
return end_page - start_page;
|
|
}
|
|
EXPORT_SYMBOL(p9_nr_pages);
|
|
|
|
/**
|
|
* payload_gup - Translates user buffer into kernel pages and
|
|
* pins them either for read/write through get_user_pages_fast().
|
|
* @req: Request to be sent to server.
|
|
* @pdata_off: data offset into the first page after translation (gup).
|
|
* @pdata_len: Total length of the IO. gup may not return requested # of pages.
|
|
* @nr_pages: number of pages to accommodate the payload
|
|
* @rw: Indicates if the pages are for read or write.
|
|
*/
|
|
|
|
int p9_payload_gup(char *data, int *nr_pages, struct page **pages, int write)
|
|
{
|
|
int nr_mapped_pages;
|
|
|
|
nr_mapped_pages = get_user_pages_fast((unsigned long)data,
|
|
*nr_pages, write, pages);
|
|
if (nr_mapped_pages <= 0)
|
|
return nr_mapped_pages;
|
|
|
|
*nr_pages = nr_mapped_pages;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(p9_payload_gup);
|