Commit 8b004457 authored by Milan Broz's avatar Milan Broz Committed by Linus Torvalds

[PATCH] dm crypt: restructure for workqueue change

Restructure part of the dm-crypt code in preparation for workqueue changes.

Use 'base_bio' or 'clone' variable names consistently throughout.  No
functional changes are included in this patch.
Signed-off-by: default avatarMilan Broz <mbroz@redhat.com>
Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent e48d4bbf
......@@ -30,7 +30,7 @@
*/
struct crypt_io {
struct dm_target *target;
struct bio *bio;
struct bio *base_bio;
struct bio *first_clone;
struct work_struct work;
atomic_t pending;
......@@ -319,7 +319,7 @@ static struct bio *
crypt_alloc_buffer(struct crypt_config *cc, unsigned int size,
struct bio *base_bio, unsigned int *bio_vec_idx)
{
struct bio *bio;
struct bio *clone;
unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM;
unsigned int i;
......@@ -330,23 +330,23 @@ crypt_alloc_buffer(struct crypt_config *cc, unsigned int size,
* FIXME: Is this really intelligent?
*/
if (base_bio)
bio = bio_clone(base_bio, GFP_NOIO|__GFP_NOMEMALLOC);
clone = bio_clone(base_bio, GFP_NOIO|__GFP_NOMEMALLOC);
else
bio = bio_alloc(GFP_NOIO|__GFP_NOMEMALLOC, nr_iovecs);
if (!bio)
clone = bio_alloc(GFP_NOIO|__GFP_NOMEMALLOC, nr_iovecs);
if (!clone)
return NULL;
/* if the last bio was not complete, continue where that one ended */
bio->bi_idx = *bio_vec_idx;
bio->bi_vcnt = *bio_vec_idx;
bio->bi_size = 0;
bio->bi_flags &= ~(1 << BIO_SEG_VALID);
clone->bi_idx = *bio_vec_idx;
clone->bi_vcnt = *bio_vec_idx;
clone->bi_size = 0;
clone->bi_flags &= ~(1 << BIO_SEG_VALID);
/* bio->bi_idx pages have already been allocated */
size -= bio->bi_idx * PAGE_SIZE;
/* clone->bi_idx pages have already been allocated */
size -= clone->bi_idx * PAGE_SIZE;
for(i = bio->bi_idx; i < nr_iovecs; i++) {
struct bio_vec *bv = bio_iovec_idx(bio, i);
for (i = clone->bi_idx; i < nr_iovecs; i++) {
struct bio_vec *bv = bio_iovec_idx(clone, i);
bv->bv_page = mempool_alloc(cc->page_pool, gfp_mask);
if (!bv->bv_page)
......@@ -357,7 +357,7 @@ crypt_alloc_buffer(struct crypt_config *cc, unsigned int size,
* return a partially allocated bio, the caller will then try
* to allocate additional bios while submitting this partial bio
*/
if ((i - bio->bi_idx) == (MIN_BIO_PAGES - 1))
if ((i - clone->bi_idx) == (MIN_BIO_PAGES - 1))
gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT;
bv->bv_offset = 0;
......@@ -366,13 +366,13 @@ crypt_alloc_buffer(struct crypt_config *cc, unsigned int size,
else
bv->bv_len = size;
bio->bi_size += bv->bv_len;
bio->bi_vcnt++;
clone->bi_size += bv->bv_len;
clone->bi_vcnt++;
size -= bv->bv_len;
}
if (!bio->bi_size) {
bio_put(bio);
if (!clone->bi_size) {
bio_put(clone);
return NULL;
}
......@@ -380,13 +380,13 @@ crypt_alloc_buffer(struct crypt_config *cc, unsigned int size,
* Remember the last bio_vec allocated to be able
* to correctly continue after the splitting.
*/
*bio_vec_idx = bio->bi_vcnt;
*bio_vec_idx = clone->bi_vcnt;
return bio;
return clone;
}
static void crypt_free_buffer_pages(struct crypt_config *cc,
struct bio *bio, unsigned int bytes)
struct bio *clone, unsigned int bytes)
{
unsigned int i, start, end;
struct bio_vec *bv;
......@@ -400,19 +400,19 @@ static void crypt_free_buffer_pages(struct crypt_config *cc,
* A fix to the bi_idx issue in the kernel is in the works, so
* we will hopefully be able to revert to the cleaner solution soon.
*/
i = bio->bi_vcnt - 1;
bv = bio_iovec_idx(bio, i);
end = (i << PAGE_SHIFT) + (bv->bv_offset + bv->bv_len) - bio->bi_size;
i = clone->bi_vcnt - 1;
bv = bio_iovec_idx(clone, i);
end = (i << PAGE_SHIFT) + (bv->bv_offset + bv->bv_len) - clone->bi_size;
start = end - bytes;
start >>= PAGE_SHIFT;
if (!bio->bi_size)
end = bio->bi_vcnt;
if (!clone->bi_size)
end = clone->bi_vcnt;
else
end >>= PAGE_SHIFT;
for(i = start; i < end; i++) {
bv = bio_iovec_idx(bio, i);
for (i = start; i < end; i++) {
bv = bio_iovec_idx(clone, i);
BUG_ON(!bv->bv_page);
mempool_free(bv->bv_page, cc->page_pool);
bv->bv_page = NULL;
......@@ -436,7 +436,7 @@ static void dec_pending(struct crypt_io *io, int error)
if (io->first_clone)
bio_put(io->first_clone);
bio_endio(io->bio, io->bio->bi_size, io->error);
bio_endio(io->base_bio, io->base_bio->bi_size, io->error);
mempool_free(io, cc->io_pool);
}
......@@ -449,25 +449,133 @@ static void dec_pending(struct crypt_io *io, int error)
* queued here.
*/
static struct workqueue_struct *_kcryptd_workqueue;
static void kcryptd_do_work(void *data);
static void kcryptd_do_work(void *data)
static void kcryptd_queue_io(struct crypt_io *io)
{
struct crypt_io *io = (struct crypt_io *) data;
struct crypt_config *cc = (struct crypt_config *) io->target->private;
INIT_WORK(&io->work, kcryptd_do_work, io);
queue_work(_kcryptd_workqueue, &io->work);
}
static int crypt_endio(struct bio *clone, unsigned int done, int error)
{
struct crypt_io *io = clone->bi_private;
struct crypt_config *cc = io->target->private;
unsigned read_io = bio_data_dir(clone) == READ;
/*
* free the processed pages, even if
* it's only a partially completed write
*/
if (!read_io)
crypt_free_buffer_pages(cc, clone, done);
if (unlikely(clone->bi_size))
return 1;
/*
* successful reads are decrypted by the worker thread
*/
if (!read_io)
goto out;
if (unlikely(!bio_flagged(clone, BIO_UPTODATE))) {
error = -EIO;
goto out;
}
bio_put(clone);
kcryptd_queue_io(io);
return 0;
out:
bio_put(clone);
dec_pending(io, error);
return error;
}
static void clone_init(struct crypt_io *io, struct bio *clone)
{
struct crypt_config *cc = io->target->private;
clone->bi_private = io;
clone->bi_end_io = crypt_endio;
clone->bi_bdev = cc->dev->bdev;
clone->bi_rw = io->base_bio->bi_rw;
}
static struct bio *clone_read(struct crypt_io *io,
sector_t sector)
{
struct crypt_config *cc = io->target->private;
struct bio *base_bio = io->base_bio;
struct bio *clone;
/*
* The block layer might modify the bvec array, so always
* copy the required bvecs because we need the original
* one in order to decrypt the whole bio data *afterwards*.
*/
clone = bio_alloc(GFP_NOIO, bio_segments(base_bio));
if (unlikely(!clone))
return NULL;
clone_init(io, clone);
clone->bi_idx = 0;
clone->bi_vcnt = bio_segments(base_bio);
clone->bi_size = base_bio->bi_size;
memcpy(clone->bi_io_vec, bio_iovec(base_bio),
sizeof(struct bio_vec) * clone->bi_vcnt);
clone->bi_sector = cc->start + sector;
return clone;
}
static struct bio *clone_write(struct crypt_io *io,
sector_t sector,
unsigned *bvec_idx,
struct convert_context *ctx)
{
struct crypt_config *cc = io->target->private;
struct bio *base_bio = io->base_bio;
struct bio *clone;
clone = crypt_alloc_buffer(cc, base_bio->bi_size,
io->first_clone, bvec_idx);
if (!clone)
return NULL;
ctx->bio_out = clone;
if (unlikely(crypt_convert(cc, ctx) < 0)) {
crypt_free_buffer_pages(cc, clone,
clone->bi_size);
bio_put(clone);
return NULL;
}
clone_init(io, clone);
clone->bi_sector = cc->start + sector;
return clone;
}
static void process_read_endio(struct crypt_io *io)
{
struct crypt_config *cc = io->target->private;
struct convert_context ctx;
int r;
crypt_convert_init(cc, &ctx, io->bio, io->bio,
io->bio->bi_sector - io->target->begin, 0);
r = crypt_convert(cc, &ctx);
crypt_convert_init(cc, &ctx, io->base_bio, io->base_bio,
io->base_bio->bi_sector - io->target->begin, 0);
dec_pending(io, r);
dec_pending(io, crypt_convert(cc, &ctx));
}
static void kcryptd_queue_io(struct crypt_io *io)
static void kcryptd_do_work(void *data)
{
INIT_WORK(&io->work, kcryptd_do_work, io);
queue_work(_kcryptd_workqueue, &io->work);
struct crypt_io *io = data;
process_read_endio(io);
}
/*
......@@ -481,7 +589,7 @@ static int crypt_decode_key(u8 *key, char *hex, unsigned int size)
buffer[2] = '\0';
for(i = 0; i < size; i++) {
for (i = 0; i < size; i++) {
buffer[0] = *hex++;
buffer[1] = *hex++;
......@@ -504,7 +612,7 @@ static void crypt_encode_key(char *hex, u8 *key, unsigned int size)
{
unsigned int i;
for(i = 0; i < size; i++) {
for (i = 0; i < size; i++) {
sprintf(hex, "%02x", *key);
hex += 2;
key++;
......@@ -725,88 +833,10 @@ static void crypt_dtr(struct dm_target *ti)
kfree(cc);
}
static int crypt_endio(struct bio *bio, unsigned int done, int error)
{
struct crypt_io *io = (struct crypt_io *) bio->bi_private;
struct crypt_config *cc = (struct crypt_config *) io->target->private;
if (bio_data_dir(bio) == WRITE) {
/*
* free the processed pages, even if
* it's only a partially completed write
*/
crypt_free_buffer_pages(cc, bio, done);
}
if (bio->bi_size)
return 1;
bio_put(bio);
/*
* successful reads are decrypted by the worker thread
*/
if ((bio_data_dir(bio) == READ)
&& bio_flagged(bio, BIO_UPTODATE)) {
kcryptd_queue_io(io);
return 0;
}
dec_pending(io, error);
return error;
}
static inline struct bio *
crypt_clone(struct crypt_config *cc, struct crypt_io *io, struct bio *bio,
sector_t sector, unsigned int *bvec_idx,
struct convert_context *ctx)
{
struct bio *clone;
if (bio_data_dir(bio) == WRITE) {
clone = crypt_alloc_buffer(cc, bio->bi_size,
io->first_clone, bvec_idx);
if (clone) {
ctx->bio_out = clone;
if (crypt_convert(cc, ctx) < 0) {
crypt_free_buffer_pages(cc, clone,
clone->bi_size);
bio_put(clone);
return NULL;
}
}
} else {
/*
* The block layer might modify the bvec array, so always
* copy the required bvecs because we need the original
* one in order to decrypt the whole bio data *afterwards*.
*/
clone = bio_alloc(GFP_NOIO, bio_segments(bio));
if (clone) {
clone->bi_idx = 0;
clone->bi_vcnt = bio_segments(bio);
clone->bi_size = bio->bi_size;
memcpy(clone->bi_io_vec, bio_iovec(bio),
sizeof(struct bio_vec) * clone->bi_vcnt);
}
}
if (!clone)
return NULL;
clone->bi_private = io;
clone->bi_end_io = crypt_endio;
clone->bi_bdev = cc->dev->bdev;
clone->bi_sector = cc->start + sector;
clone->bi_rw = bio->bi_rw;
return clone;
}
static int crypt_map(struct dm_target *ti, struct bio *bio,
union map_info *map_context)
{
struct crypt_config *cc = (struct crypt_config *) ti->private;
struct crypt_config *cc = ti->private;
struct crypt_io *io;
struct convert_context ctx;
struct bio *clone;
......@@ -816,7 +846,7 @@ static int crypt_map(struct dm_target *ti, struct bio *bio,
io = mempool_alloc(cc->io_pool, GFP_NOIO);
io->target = ti;
io->bio = bio;
io->base_bio = bio;
io->first_clone = NULL;
io->error = 0;
atomic_set(&io->pending, 1); /* hold a reference */
......@@ -829,7 +859,10 @@ static int crypt_map(struct dm_target *ti, struct bio *bio,
* so repeat the whole process until all the data can be handled.
*/
while (remaining) {
clone = crypt_clone(cc, io, bio, sector, &bvec_idx, &ctx);
if (bio_data_dir(bio) == WRITE)
clone = clone_write(io, sector, &bvec_idx, &ctx);
else
clone = clone_read(io, sector);
if (!clone)
goto cleanup;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment