Files
kernel_xiaomi_raphael/include/linux/bvec.h
Shivaprasad Hongal 367c46b11c Enable hardware based FBE on f2fs and adapt ext4 fs
Hardware File Based Encryption (FBE) uses inline crypto
engine to encrypt the user data.
1. security/pfk: changes to support per file
   encryption for f2fs using hardware crypto engine.
2. fs/ext4: adapted crypto APIs for generic crypto layer.
3. fs/f2fs: support hardware crypto engine based per file
   encryption.
4. fs/crypto: export APIs to support hardware crypto
   engine based per file encryption.
5. security/pfe: added wrapped key support based on
   upstream changes.
Other changes made to provide support framework for per
file encryption.

Reverting commit e02a4e21f6 ("ext4: Add HW File Based
Encryption on ext4 file system") and adding changes to
have FBE in sync with upstream implementation of FBE.

Change-Id: I17f9909c43ba744eb874f6d237745fbf88a2b848
Signed-off-by: Shivaprasad Hongal <shongal@codeaurora.org>
2018-08-22 10:56:07 -07:00

130 lines
3.5 KiB
C

/*
* bvec iterator
*
* Copyright (C) 2001 Ming Lei <ming.lei@canonical.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
*
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public Licens
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
*/
#ifndef __LINUX_BVEC_ITER_H
#define __LINUX_BVEC_ITER_H
#include <linux/kernel.h>
#include <linux/bug.h>
#include <linux/errno.h>
/*
* was unsigned short, but we might as well be ready for > 64kB I/O pages
*/
struct bio_vec {
struct page *bv_page;
unsigned int bv_len;
unsigned int bv_offset;
};
struct bvec_iter {
sector_t bi_sector; /* device address in 512 byte
sectors */
unsigned int bi_size; /* residual I/O count */
unsigned int bi_idx; /* current index into bvl_vec */
unsigned int bi_done; /* number of bytes completed */
unsigned int bi_bvec_done; /* number of bytes completed in
current bvec */
u64 bi_dun; /* DUN setting for bio */
};
/*
* various member access, note that bio_data should of course not be used
* on highmem page vectors
*/
#define __bvec_iter_bvec(bvec, iter) (&(bvec)[(iter).bi_idx])
#define bvec_iter_page(bvec, iter) \
(__bvec_iter_bvec((bvec), (iter))->bv_page)
#define bvec_iter_len(bvec, iter) \
min((iter).bi_size, \
__bvec_iter_bvec((bvec), (iter))->bv_len - (iter).bi_bvec_done)
#define bvec_iter_offset(bvec, iter) \
(__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done)
#define bvec_iter_bvec(bvec, iter) \
((struct bio_vec) { \
.bv_page = bvec_iter_page((bvec), (iter)), \
.bv_len = bvec_iter_len((bvec), (iter)), \
.bv_offset = bvec_iter_offset((bvec), (iter)), \
})
static inline bool bvec_iter_advance(const struct bio_vec *bv,
struct bvec_iter *iter, unsigned bytes)
{
if (WARN_ONCE(bytes > iter->bi_size,
"Attempted to advance past end of bvec iter\n")) {
iter->bi_size = 0;
return false;
}
while (bytes) {
unsigned iter_len = bvec_iter_len(bv, *iter);
unsigned len = min(bytes, iter_len);
bytes -= len;
iter->bi_size -= len;
iter->bi_bvec_done += len;
iter->bi_done += len;
if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
iter->bi_bvec_done = 0;
iter->bi_idx++;
}
}
return true;
}
static inline bool bvec_iter_rewind(const struct bio_vec *bv,
struct bvec_iter *iter,
unsigned int bytes)
{
while (bytes) {
unsigned len = min(bytes, iter->bi_bvec_done);
if (iter->bi_bvec_done == 0) {
if (WARN_ONCE(iter->bi_idx == 0,
"Attempted to rewind iter beyond "
"bvec's boundaries\n")) {
return false;
}
iter->bi_idx--;
iter->bi_bvec_done = __bvec_iter_bvec(bv, *iter)->bv_len;
continue;
}
bytes -= len;
iter->bi_size += len;
iter->bi_bvec_done -= len;
}
return true;
}
#define for_each_bvec(bvl, bio_vec, iter, start) \
for (iter = (start); \
(iter).bi_size && \
((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \
bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
#endif /* __LINUX_BVEC_ITER_H */