Revision f9ebd61855253078fe8b07bacaf516337f8078e8 authored by Anna Schumaker on 15 April 2015, 17:00:04 UTC, committed by Trond Myklebust on 23 April 2015, 19:16:13 UTC
The idmapper is completely internal to the NFS v4 module, so this macro will always evaluate to true. This patch also removes unnecessary includes of this file from the generic NFS client. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
1 parent 7c61f0d
bounce.c
/* bounce buffer handling for block devices
*
* - Split from highmem.c
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/mm.h>
#include <linux/export.h>
#include <linux/swap.h>
#include <linux/gfp.h>
#include <linux/bio.h>
#include <linux/pagemap.h>
#include <linux/mempool.h>
#include <linux/blkdev.h>
#include <linux/init.h>
#include <linux/hash.h>
#include <linux/highmem.h>
#include <linux/bootmem.h>
#include <linux/printk.h>
#include <asm/tlbflush.h>
#include <trace/events/block.h>
#define POOL_SIZE 64
#define ISA_POOL_SIZE 16
static mempool_t *page_pool, *isa_page_pool;
#if defined(CONFIG_HIGHMEM) || defined(CONFIG_NEED_BOUNCE_POOL)
static __init int init_emergency_pool(void)
{
#if defined(CONFIG_HIGHMEM) && !defined(CONFIG_MEMORY_HOTPLUG)
if (max_pfn <= max_low_pfn)
return 0;
#endif
page_pool = mempool_create_page_pool(POOL_SIZE, 0);
BUG_ON(!page_pool);
pr_info("pool size: %d pages\n", POOL_SIZE);
return 0;
}
__initcall(init_emergency_pool);
#endif
#ifdef CONFIG_HIGHMEM
/*
* highmem version, map in to vec
*/
static void bounce_copy_vec(struct bio_vec *to, unsigned char *vfrom)
{
unsigned long flags;
unsigned char *vto;
local_irq_save(flags);
vto = kmap_atomic(to->bv_page);
memcpy(vto + to->bv_offset, vfrom, to->bv_len);
kunmap_atomic(vto);
local_irq_restore(flags);
}
#else /* CONFIG_HIGHMEM */
#define bounce_copy_vec(to, vfrom) \
memcpy(page_address((to)->bv_page) + (to)->bv_offset, vfrom, (to)->bv_len)
#endif /* CONFIG_HIGHMEM */
/*
* allocate pages in the DMA region for the ISA pool
*/
static void *mempool_alloc_pages_isa(gfp_t gfp_mask, void *data)
{
return mempool_alloc_pages(gfp_mask | GFP_DMA, data);
}
/*
* gets called "every" time someone init's a queue with BLK_BOUNCE_ISA
* as the max address, so check if the pool has already been created.
*/
int init_emergency_isa_pool(void)
{
if (isa_page_pool)
return 0;
isa_page_pool = mempool_create(ISA_POOL_SIZE, mempool_alloc_pages_isa,
mempool_free_pages, (void *) 0);
BUG_ON(!isa_page_pool);
pr_info("isa pool size: %d pages\n", ISA_POOL_SIZE);
return 0;
}
/*
* Simple bounce buffer support for highmem pages. Depending on the
* queue gfp mask set, *to may or may not be a highmem page. kmap it
* always, it will do the Right Thing
*/
static void copy_to_high_bio_irq(struct bio *to, struct bio *from)
{
unsigned char *vfrom;
struct bio_vec tovec, *fromvec = from->bi_io_vec;
struct bvec_iter iter;
bio_for_each_segment(tovec, to, iter) {
if (tovec.bv_page != fromvec->bv_page) {
/*
* fromvec->bv_offset and fromvec->bv_len might have
* been modified by the block layer, so use the original
* copy, bounce_copy_vec already uses tovec->bv_len
*/
vfrom = page_address(fromvec->bv_page) +
tovec.bv_offset;
bounce_copy_vec(&tovec, vfrom);
flush_dcache_page(tovec.bv_page);
}
fromvec++;
}
}
static void bounce_end_io(struct bio *bio, mempool_t *pool, int err)
{
struct bio *bio_orig = bio->bi_private;
struct bio_vec *bvec, *org_vec;
int i;
if (test_bit(BIO_EOPNOTSUPP, &bio->bi_flags))
set_bit(BIO_EOPNOTSUPP, &bio_orig->bi_flags);
/*
* free up bounce indirect pages used
*/
bio_for_each_segment_all(bvec, bio, i) {
org_vec = bio_orig->bi_io_vec + i;
if (bvec->bv_page == org_vec->bv_page)
continue;
dec_zone_page_state(bvec->bv_page, NR_BOUNCE);
mempool_free(bvec->bv_page, pool);
}
bio_endio(bio_orig, err);
bio_put(bio);
}
static void bounce_end_io_write(struct bio *bio, int err)
{
bounce_end_io(bio, page_pool, err);
}
static void bounce_end_io_write_isa(struct bio *bio, int err)
{
bounce_end_io(bio, isa_page_pool, err);
}
static void __bounce_end_io_read(struct bio *bio, mempool_t *pool, int err)
{
struct bio *bio_orig = bio->bi_private;
if (test_bit(BIO_UPTODATE, &bio->bi_flags))
copy_to_high_bio_irq(bio_orig, bio);
bounce_end_io(bio, pool, err);
}
static void bounce_end_io_read(struct bio *bio, int err)
{
__bounce_end_io_read(bio, page_pool, err);
}
static void bounce_end_io_read_isa(struct bio *bio, int err)
{
__bounce_end_io_read(bio, isa_page_pool, err);
}
#ifdef CONFIG_NEED_BOUNCE_POOL
static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio)
{
if (bio_data_dir(bio) != WRITE)
return 0;
if (!bdi_cap_stable_pages_required(&q->backing_dev_info))
return 0;
return test_bit(BIO_SNAP_STABLE, &bio->bi_flags);
}
#else
static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio)
{
return 0;
}
#endif /* CONFIG_NEED_BOUNCE_POOL */
static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig,
mempool_t *pool, int force)
{
struct bio *bio;
int rw = bio_data_dir(*bio_orig);
struct bio_vec *to, from;
struct bvec_iter iter;
unsigned i;
if (force)
goto bounce;
bio_for_each_segment(from, *bio_orig, iter)
if (page_to_pfn(from.bv_page) > queue_bounce_pfn(q))
goto bounce;
return;
bounce:
bio = bio_clone_bioset(*bio_orig, GFP_NOIO, fs_bio_set);
bio_for_each_segment_all(to, bio, i) {
struct page *page = to->bv_page;
if (page_to_pfn(page) <= queue_bounce_pfn(q) && !force)
continue;
inc_zone_page_state(to->bv_page, NR_BOUNCE);
to->bv_page = mempool_alloc(pool, q->bounce_gfp);
if (rw == WRITE) {
char *vto, *vfrom;
flush_dcache_page(page);
vto = page_address(to->bv_page) + to->bv_offset;
vfrom = kmap_atomic(page) + to->bv_offset;
memcpy(vto, vfrom, to->bv_len);
kunmap_atomic(vfrom);
}
}
trace_block_bio_bounce(q, *bio_orig);
bio->bi_flags |= (1 << BIO_BOUNCED);
if (pool == page_pool) {
bio->bi_end_io = bounce_end_io_write;
if (rw == READ)
bio->bi_end_io = bounce_end_io_read;
} else {
bio->bi_end_io = bounce_end_io_write_isa;
if (rw == READ)
bio->bi_end_io = bounce_end_io_read_isa;
}
bio->bi_private = *bio_orig;
*bio_orig = bio;
}
void blk_queue_bounce(struct request_queue *q, struct bio **bio_orig)
{
int must_bounce;
mempool_t *pool;
/*
* Data-less bio, nothing to bounce
*/
if (!bio_has_data(*bio_orig))
return;
must_bounce = must_snapshot_stable_pages(q, *bio_orig);
/*
* for non-isa bounce case, just check if the bounce pfn is equal
* to or bigger than the highest pfn in the system -- in that case,
* don't waste time iterating over bio segments
*/
if (!(q->bounce_gfp & GFP_DMA)) {
if (queue_bounce_pfn(q) >= blk_max_pfn && !must_bounce)
return;
pool = page_pool;
} else {
BUG_ON(!isa_page_pool);
pool = isa_page_pool;
}
/*
* slow path
*/
__blk_queue_bounce(q, bio_orig, pool, must_bounce);
}
EXPORT_SYMBOL(blk_queue_bounce);
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...