Files
Albert I b5ab97f74f Merge branch 'android-4.9.236-q-merge' into a11
* android-4.9.236-q-merge: (72 commits)
  Linux 4.9.236
  net: disable netpoll on fresh napis
  sctp: not disable bh in the whole sctp_get_port_local()
  net: usb: dm9601: Add USB ID of Keenetic Plus DSL
  netlabel: fix problems with mapping removal
  bnxt: don't enable NAPI until rings are ready
  net: ethernet: mlx4: Fix memory allocation in mlx4_buddy_init()
  affs: fix basic permission bits to actually work
  fs/affs: use octal for permissions
  ALSA; firewire-tascam: exclude Tascam FE-8 from detection
  net: usb: Fix uninit-was-stored issue in asix_read_phy_addr()
  cfg80211: regulatory: reject invalid hints
  mm/hugetlb: fix a race between hugetlb sysctl handlers
  checkpatch: fix the usage of capture group ( ... )
  vfio/pci: Fix SR-IOV VF handling with MMIO blocking
  net: initialize fastreuse on inet_inherit_port
  net: refactor bind_bucket fastreuse into helper
  KVM: arm64: Set HCR_EL2.PTW to prevent AT taking synchronous exception
  KVM: arm64: Survive synchronous exceptions caused by AT instructions
  KVM: arm64: Defer guest entry when an asynchronous exception is pending
  ...

Signed-off-by: Albert I <kras@raphielgang.org>
2020-11-07 22:52:49 +08:00

108 lines
3.0 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>
/*
* 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_bvec_done; /* number of bytes completed in
current bvec */
#ifdef CONFIG_PFK
u64 bi_dun; /* DUN setting for bio */
#endif
};
/*
* 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 void bvec_iter_advance(const struct bio_vec *bv,
struct bvec_iter *iter,
unsigned bytes)
{
WARN_ONCE(bytes > iter->bi_size,
"Attempted to advance past end of bvec iter\n");
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;
if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
iter->bi_bvec_done = 0;
iter->bi_idx++;
}
}
}
static inline void bvec_iter_skip_zero_bvec(struct bvec_iter *iter)
{
iter->bi_bvec_done = 0;
iter->bi_idx++;
}
#define for_each_bvec(bvl, bio_vec, iter, start) \
for (iter = (start); \
(iter).bi_size && \
((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \
(bvl).bv_len ? (void)bvec_iter_advance((bio_vec), &(iter), \
(bvl).bv_len) : bvec_iter_skip_zero_bvec(&(iter)))
#endif /* __LINUX_BVEC_ITER_H */