mirror of
https://github.com/schoebel/mars
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864 lines
21 KiB
C
864 lines
21 KiB
C
// (c) 2010 Thomas Schoebel-Theuer / 1&1 Internet AG
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/* Interface to a Linux device.
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* 1 Input, 0 Outputs.
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*/
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//#define BRICK_DEBUGGING
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//#define MARS_DEBUGGING
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//#define IO_DEBUGGING
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#define REQUEST_MERGING
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//#define ALWAYS_UNPLUG false
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#define ALWAYS_UNPLUG true
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#define PREFETCH_LEN PAGE_SIZE
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//#define FRONT_MERGE // FIXME: this does not work.
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// low-level device parameters
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//#define USE_MAX_SECTORS (MARS_MAX_SEGMENT_SIZE >> 9)
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//#define USE_MAX_PHYS_SEGMENTS (MARS_MAX_SEGMENT_SIZE >> 9)
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//#define USE_MAX_SEGMENT_SIZE MARS_MAX_SEGMENT_SIZE
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//#define USE_LOGICAL_BLOCK_SIZE 512
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//#define USE_SEGMENT_BOUNDARY (PAGE_SIZE-1)
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//#define USE_QUEUE_ORDERED QUEUE_ORDERED_DRAIN
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//#define USE_CONGESTED_FN
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#define USE_MERGE_BVEC
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/string.h>
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#include <linux/major.h>
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#include <linux/genhd.h>
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#include <linux/blkdev.h>
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#include "mars.h"
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///////////////////////// own type definitions ////////////////////////
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#include "mars_if.h"
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///////////////////////// own static definitions ////////////////////////
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// TODO: check bounds, ensure that free minor numbers are recycled
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static int device_minor = 0;
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//////////////// object / aspect constructors / destructors ///////////////
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///////////////////////// linux operations ////////////////////////
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/* callback
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*/
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static
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void if_endio(struct generic_callback *cb)
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{
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struct if_mref_aspect *mref_a = cb->cb_private;
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struct if_input *input;
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struct bio *bio;
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int k;
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int rw = 0;
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int error;
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if (unlikely(!mref_a)) {
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MARS_FAT("callback with no mref_a called. something is very wrong here!\n");
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return;
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}
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mars_trace(mref_a->object, "if_endio");
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mars_log_trace(mref_a->object);
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for (k = 0; k < mref_a->bio_count; k++) {
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bio = mref_a->orig_bio[k];
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mref_a->orig_bio[k] = NULL;
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if (unlikely(!bio)) {
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MARS_FAT("callback with no bio called (k = %d). something is very wrong here!\n", k);
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continue;
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}
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rw = bio->bi_rw & 1;
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CHECK_ATOMIC(&bio->bi_comp_cnt, 1);
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if (!atomic_dec_and_test(&bio->bi_comp_cnt)) {
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continue;
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}
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#if 1
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if (mref_a->is_kmapped) {
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struct bio_vec *bvec;
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int i;
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bio_for_each_segment(bvec, bio, i) {
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MARS_IO("kunmap %p\n", bvec->bv_page);
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kunmap(bvec->bv_page);
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}
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}
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#endif
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error = mref_a->cb.cb_error;
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if (unlikely(error < 0)) {
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MARS_ERR("NYI: error=%d RETRY LOGIC %u\n", error, bio->bi_size);
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} else { // bio conventions are slightly different...
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error = 0;
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bio->bi_size = 0;
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}
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bio_endio(bio, error);
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bio_put(bio);
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}
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input = mref_a->input;
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if (input) {
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atomic_dec(&input->flying_count);
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if (rw) {
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atomic_dec(&input->write_flying_count);
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} else {
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atomic_dec(&input->read_flying_count);
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}
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}
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}
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/* Kick off plugged mrefs
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*/
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static
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void _if_unplug(struct if_input *input)
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{
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//struct if_brick *brick = input->brick;
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LIST_HEAD(tmp_list);
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unsigned long flags;
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might_sleep();
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down(&input->kick_sem);
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traced_lock(&input->req_lock, flags);
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#ifdef USE_TIMER
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del_timer(&input->timer);
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#endif
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if (!list_empty(&input->plug_anchor)) {
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// move over the whole list
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list_replace_init(&input->plug_anchor, &tmp_list);
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atomic_set(&input->plugged_count, 0);
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}
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traced_unlock(&input->req_lock, flags);
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up(&input->kick_sem);
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while (!list_empty(&tmp_list)) {
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struct if_mref_aspect *mref_a;
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struct mref_object *mref;
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int hash_index;
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unsigned long flags;
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mref_a = container_of(tmp_list.next, struct if_mref_aspect, plug_head);
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list_del_init(&mref_a->plug_head);
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hash_index = mref_a->hash_index;
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traced_lock(&input->hash_lock[hash_index], flags);
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list_del_init(&mref_a->hash_head);
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traced_unlock(&input->hash_lock[hash_index], flags);
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mref = mref_a->object;
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if (unlikely(mref_a->current_len > mref_a->max_len)) {
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MARS_ERR("request len %d > %d\n", mref_a->current_len, mref_a->max_len);
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}
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mref->ref_len = mref_a->current_len;
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mars_trace(mref, "if_unplug");
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atomic_inc(&input->flying_count);
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if (mref->ref_rw) {
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atomic_inc(&input->write_flying_count);
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} else {
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atomic_inc(&input->read_flying_count);
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}
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GENERIC_INPUT_CALL(input, mref_io, mref);
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GENERIC_INPUT_CALL(input, mref_put, mref);
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}
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}
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#ifdef USE_TIMER
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static
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void if_timer(unsigned long data)
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{
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_if_unplug((void*)data);
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}
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#endif
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/* accept a linux bio, convert to mref and call buf_io() on it.
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*/
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static int if_make_request(struct request_queue *q, struct bio *bio)
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{
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struct if_input *input;
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struct if_brick *brick = NULL;
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struct mref_object *mref = NULL;
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struct if_mref_aspect *mref_a;
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struct generic_callback *cb;
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struct bio_vec *bvec;
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int i;
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bool assigned = false;
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const bool unplug = bio_rw_flagged(bio, BIO_RW_UNPLUG);
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const bool barrier = ((bio->bi_rw & 1) != READ && bio_rw_flagged(bio, BIO_RW_BARRIER));
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loff_t pos = ((loff_t)bio->bi_sector) << 9; // TODO: make dynamic
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int rw = bio_data_dir(bio);
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int total_len = bio->bi_size;
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int error = -ENOSYS;
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MARS_IO("bio %p size = %d\n", bio, bio->bi_size);
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might_sleep();
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input = q->queuedata;
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if (unlikely(!input))
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goto err;
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if (unlikely(!bio_sectors(bio))) {
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atomic_inc(&input->total_empty_count);
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_if_unplug(input);
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/* THINK: usually this happens only at write barriers.
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* We have no "barrier" operation in MARS, since
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* callback semantics should always denote
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* "writethrough accomplished".
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* In case of exceptional semantics, we need to do
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* something here. For now, we do just nothing.
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*/
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bio_endio(bio, 0);
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return 0;
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}
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if (rw) {
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atomic_inc(&input->total_write_count);
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} else {
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atomic_inc(&input->total_read_count);
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}
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brick = input->brick;
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if (unlikely(!brick))
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goto err;
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/* Get a reference to the bio.
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* Will be released after bio_endio().
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*/
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atomic_inc(&bio->bi_cnt);
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/* FIXME: THIS IS PROVISIONARY (use event instead)
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*/
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while (unlikely(!brick->power.led_on)) {
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msleep(2 * HZ);
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}
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_CHECK_ATOMIC(&bio->bi_comp_cnt, !=, 0);
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atomic_set(&bio->bi_comp_cnt, 0);
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#ifdef IO_DEBUGGING
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{
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const unsigned short prio = bio_prio(bio);
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const bool sync = bio_rw_flagged(bio, BIO_RW_SYNCIO);
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const unsigned int ff = bio->bi_rw & REQ_FAILFAST_MASK;
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MARS_IO("BIO rw = %lx len = %d prio = %d sync = %d unplug = %d ff = %d\n", bio->bi_rw, bio->bi_size, prio, sync, unplug, ff);
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}
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#endif
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down(&input->kick_sem);
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bio_for_each_segment(bvec, bio, i) {
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struct page *page = bvec->bv_page;
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int bv_len = bvec->bv_len;
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int offset = bvec->bv_offset;
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void *data;
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data = kmap(page);
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MARS_IO("page = %p data = %p\n", page, data);
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error = -EINVAL;
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if (unlikely(!data))
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break;
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data += offset;
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while (bv_len > 0) {
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struct list_head *tmp;
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int hash_index;
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int this_len = 0;
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unsigned long flags;
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mref = NULL;
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mref_a = NULL;
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MARS_IO("rw = %d i = %d pos = %lld bv_page = %p bv_offset = %d data = %p bv_len = %d\n", rw, i, pos, bvec->bv_page, bvec->bv_offset, data, bv_len);
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hash_index = (pos / IF_HASH_CHUNK) % IF_HASH_MAX;
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#ifdef REQUEST_MERGING
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traced_lock(&input->hash_lock[hash_index], flags);
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for (tmp = input->hash_table[hash_index].next; tmp != &input->hash_table[hash_index]; tmp = tmp->next) {
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struct if_mref_aspect *tmp_a;
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struct mref_object *tmp_mref;
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int i;
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tmp_a = container_of(tmp, struct if_mref_aspect, hash_head);
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tmp_mref = tmp_a->object;
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if (tmp_a->orig_page != page || tmp_mref->ref_rw != rw || tmp_a->bio_count >= MAX_BIO || tmp_a->current_len + bv_len > tmp_a->max_len) {
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continue;
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}
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if (tmp_mref->ref_data + tmp_a->current_len == data) {
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goto merge_end;
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#ifdef FRONT_MERGE // FIXME: this cannot work. ref_data must never be changed. pre-allocate from offset 0 instead.
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} else if (data + bv_len == tmp_mref->ref_data) {
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goto merge_front;
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#endif
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}
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continue;
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#ifdef FRONT_MERGE // FIXME: this cannot work. ref_data must never be changed. pre-allocate from offset 0 instead.
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merge_front:
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tmp_mref->ref_data = data;
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#endif
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merge_end:
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tmp_a->current_len += bv_len;
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mref = tmp_mref;
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mref_a = tmp_a;
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this_len = bv_len;
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if (barrier) {
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mref->ref_skip_sync = false;
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}
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for (i = 0; i < mref_a->bio_count; i++) {
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if (mref_a->orig_bio[i] == bio) {
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goto unlock;
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}
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}
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CHECK_ATOMIC(&bio->bi_comp_cnt, 0);
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atomic_inc(&bio->bi_comp_cnt);
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mref_a->orig_bio[mref_a->bio_count++] = bio;
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assigned = true;
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goto unlock;
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} // foreach hash collision list member
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unlock:
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traced_unlock(&input->hash_lock[hash_index], flags);
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#endif
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if (!mref) {
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int prefetch_len;
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error = -ENOMEM;
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mref = if_alloc_mref(&brick->hidden_output, &input->mref_object_layout);
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if (unlikely(!mref)) {
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up(&input->kick_sem);
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goto err;
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}
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mref_a = if_mref_get_aspect(&brick->hidden_output, mref);
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if (unlikely(!mref_a)) {
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up(&input->kick_sem);
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goto err;
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}
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#ifdef PREFETCH_LEN
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prefetch_len = PREFETCH_LEN - offset;
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#if 1
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// TODO: this restriction is too strong to be useful for performance boosts. Do better.
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if (prefetch_len > total_len) {
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prefetch_len = total_len;
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}
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#endif
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if (pos + prefetch_len > input->info.current_size) {
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prefetch_len = input->info.current_size - pos;
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}
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if (prefetch_len < bv_len) {
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prefetch_len = bv_len;
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}
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#else
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prefetch_len = bv_len;
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#endif
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cb = &mref_a->cb;
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cb->cb_fn = if_endio;
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cb->cb_private = mref_a;
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cb->cb_error = 0;
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cb->cb_prev = NULL;
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mref->ref_cb = cb;
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mref_a->input = input;
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mref->ref_rw = mref->ref_may_write = rw;
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mref->ref_pos = pos;
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mref->ref_len = prefetch_len;
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mref->ref_data = data; // direct IO
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mref_a->orig_page = page;
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mref_a->is_kmapped = true;
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error = GENERIC_INPUT_CALL(input, mref_get, mref);
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if (unlikely(error < 0)) {
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up(&input->kick_sem);
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goto err;
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}
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mars_trace(mref, "if_start");
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this_len = mref->ref_len; // now may be shorter than originally requested.
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mref_a->max_len = this_len;
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if (this_len > bv_len) {
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this_len = bv_len;
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}
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mref_a->current_len = this_len;
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if (rw) {
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atomic_inc(&input->total_mref_write_count);
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} else {
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atomic_inc(&input->total_mref_read_count);
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}
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CHECK_ATOMIC(&bio->bi_comp_cnt, 0);
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atomic_inc(&bio->bi_comp_cnt);
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mref_a->orig_bio[0] = bio;
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mref_a->bio_count = 1;
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assigned = true;
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if (brick->skip_sync && !barrier) {
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mref->ref_skip_sync = true;
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}
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atomic_inc(&input->plugged_count);
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mref_a->hash_index = hash_index;
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traced_lock(&input->hash_lock[hash_index], flags);
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list_add_tail(&mref_a->hash_head, &input->hash_table[hash_index]);
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traced_unlock(&input->hash_lock[hash_index], flags);
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traced_lock(&input->req_lock, flags);
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list_add_tail(&mref_a->plug_head, &input->plug_anchor);
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traced_unlock(&input->req_lock, flags);
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} // !mref
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pos += this_len;
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data += this_len;
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bv_len -= this_len;
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total_len -= this_len;
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} // while bv_len > 0
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} // foreach bvec
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up(&input->kick_sem);
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if (likely(!total_len)) {
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error = 0;
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} else {
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MARS_ERR("bad rest len = %d\n", total_len);
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}
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err:
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if (error < 0) {
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MARS_ERR("cannot submit request from bio, status=%d\n", error);
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if (assigned) {
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//... cleanup the mess NYI
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} else {
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bio_endio(bio, error);
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}
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}
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if (ALWAYS_UNPLUG || unplug ||
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(brick && brick->max_plugged > 0 && atomic_read(&input->plugged_count) > brick->max_plugged)) {
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_if_unplug(input);
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}
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#ifdef USE_TIMER
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else {
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unsigned long flags;
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traced_lock(&input->req_lock, flags);
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if (timer_pending(&input->timer)) {
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del_timer(&input->timer);
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}
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input->timer.function = if_timer;
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input->timer.data = (unsigned long)input;
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input->timer.expires = jiffies + HZ/10;
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add_timer(&input->timer);
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traced_unlock(&input->req_lock, flags);
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}
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#endif
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return error;
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}
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static int if_open(struct block_device *bdev, fmode_t mode)
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{
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struct if_input *input = bdev->bd_disk->private_data;
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atomic_inc(&input->open_count);
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MARS_INF("----------------------- OPEN %d ------------------------------\n", atomic_read(&input->open_count));
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return 0;
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}
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static int if_release(struct gendisk *gd, fmode_t mode)
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{
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struct if_input *input = gd->private_data;
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int max = 0;
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int nr;
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MARS_INF("----------------------- CLOSE %d ------------------------------\n", atomic_read(&input->open_count));
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while ((nr = atomic_read(&input->flying_count)) > 0) {
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MARS_INF("%d IO requests not yet completed\n", nr);
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if (max++ > 10)
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break;
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msleep(2000);
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}
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if (atomic_dec_and_test(&input->open_count)) {
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struct if_brick *brick = input->brick;
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brick->has_closed = true;
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mars_trigger();
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}
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return 0;
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}
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//static
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void if_unplug(struct request_queue *q)
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{
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int was_plugged = 1;
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#if 1
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spin_lock_irq(q->queue_lock);
|
|
was_plugged = blk_remove_plug(q);
|
|
spin_unlock_irq(q->queue_lock);
|
|
#else
|
|
queue_flag_clear_unlocked(QUEUE_FLAG_PLUGGED, q);
|
|
#endif
|
|
MARS_IO("UNPLUG %d\n", was_plugged);
|
|
if (true || was_plugged) {
|
|
struct if_input *input = q->queuedata;
|
|
_if_unplug(input);
|
|
}
|
|
}
|
|
|
|
//static
|
|
int mars_congested(void *data, int bdi_bits)
|
|
{
|
|
struct if_input *input = data;
|
|
int ret = 0;
|
|
if (bdi_bits & (1 << BDI_sync_congested) &&
|
|
atomic_read(&input->flying_count) > 0) {
|
|
ret |= (1 << BDI_sync_congested);
|
|
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static
|
|
int mars_merge_bvec(struct request_queue *q, struct bvec_merge_data *bvm, struct bio_vec *bvec)
|
|
{
|
|
unsigned int bio_size = bvm->bi_size;
|
|
if (!bio_size) {
|
|
return bvec->bv_len;
|
|
}
|
|
return 128;
|
|
}
|
|
|
|
static const struct block_device_operations if_blkdev_ops = {
|
|
.owner = THIS_MODULE,
|
|
.open = if_open,
|
|
.release = if_release,
|
|
|
|
};
|
|
|
|
static int if_switch(struct if_brick *brick)
|
|
{
|
|
struct if_input *input = brick->inputs[0];
|
|
struct request_queue *q;
|
|
struct gendisk *disk;
|
|
int minor;
|
|
unsigned long capacity;
|
|
int status;
|
|
|
|
if (brick->power.button) {
|
|
mars_power_led_off((void*)brick, false);
|
|
status = GENERIC_INPUT_CALL(input, mars_get_info, &input->info);
|
|
if (status < 0) {
|
|
MARS_ERR("cannot get device info, status=%d\n", status);
|
|
return status;
|
|
}
|
|
capacity = input->info.current_size >> 9; // TODO: make this dynamic
|
|
|
|
q = blk_alloc_queue(GFP_MARS);
|
|
if (!q) {
|
|
MARS_ERR("cannot allocate device request queue\n");
|
|
return -ENOMEM;
|
|
}
|
|
q->queuedata = input;
|
|
input->q = q;
|
|
|
|
disk = alloc_disk(1);
|
|
if (!disk) {
|
|
MARS_ERR("cannot allocate gendisk\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
minor = device_minor++; //TODO: protect against races (e.g. atomic_t)
|
|
disk->queue = q;
|
|
disk->major = MARS_MAJOR; //TODO: make this dynamic for >256 devices
|
|
disk->first_minor = minor;
|
|
disk->fops = &if_blkdev_ops;
|
|
//snprintf(disk->disk_name, sizeof(disk->disk_name), "mars%d", minor);
|
|
snprintf(disk->disk_name, sizeof(disk->disk_name), "mars/%s", brick->brick_name);
|
|
MARS_DBG("created device name %s\n", disk->disk_name);
|
|
disk->private_data = input;
|
|
set_capacity(disk, capacity);
|
|
|
|
blk_queue_make_request(q, if_make_request);
|
|
#ifdef USE_MAX_SECTORS
|
|
blk_queue_max_sectors(q, USE_MAX_SECTORS);
|
|
#endif
|
|
#ifdef USE_MAX_PHYS_SEGMENTS
|
|
blk_queue_max_phys_segments(q, USE_MAX_PHYS_SEGMENTS);
|
|
#endif
|
|
#ifdef USE_MAX_HW_SEGMENTS
|
|
blk_queue_max_hw_segments(q, USE_MAX_HW_SEGMENTS);
|
|
#endif
|
|
#ifdef USE_MAX_SEGMENT_SIZE
|
|
blk_queue_max_segment_size(q, USE_MAX_SEGMENT_SIZE);
|
|
#endif
|
|
#ifdef USE_LOGICAL_BLOCK_SIZE
|
|
blk_queue_logical_block_size(q, USE_LOGICAL_BLOCK_SIZE);
|
|
#endif
|
|
#ifdef USE_SEGMENT_BOUNDARY
|
|
blk_queue_segment_boundary(q, USE_SEGMENT_BOUNDARY);
|
|
#endif
|
|
#ifdef USE_QUEUE_ORDERED
|
|
blk_queue_ordered(q, USE_QUEUE_ORDERED, NULL);
|
|
#endif
|
|
blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
|
|
q->unplug_fn = if_unplug;
|
|
q->queue_lock = &input->req_lock; // needed!
|
|
|
|
input->bdev = bdget(MKDEV(disk->major, minor));
|
|
/* we have no partitions. we contain only ourselves. */
|
|
input->bdev->bd_contains = input->bdev;
|
|
|
|
MARS_INF("ra_pages OLD = %lu NEW = %d\n", q->backing_dev_info.ra_pages, brick->readahead);
|
|
q->backing_dev_info.ra_pages = brick->readahead;
|
|
#ifdef USE_CONGESTED_FN
|
|
q->backing_dev_info.congested_fn = mars_congested;
|
|
q->backing_dev_info.congested_data = input;
|
|
#endif
|
|
#ifdef USE_MERGE_BVEC
|
|
blk_queue_merge_bvec(q, mars_merge_bvec);
|
|
#endif
|
|
|
|
// point of no return
|
|
add_disk(disk);
|
|
input->disk = disk;
|
|
//set_device_ro(input->bdev, 0); // TODO: implement modes
|
|
mars_power_led_on((void*)brick, true);
|
|
} else {
|
|
mars_power_led_on((void*)brick, false);
|
|
disk = input->disk;
|
|
if (!disk)
|
|
goto is_down;
|
|
|
|
#if 0
|
|
q = disk->queue;
|
|
if (q) {
|
|
blk_cleanup_queue(q);
|
|
input->q = NULL;
|
|
}
|
|
#endif
|
|
if (atomic_read(&input->open_count) > 0) {
|
|
MARS_INF("device '%s' is open %d times, cannot shutdown\n", disk->disk_name, atomic_read(&input->open_count));
|
|
return -EBUSY;
|
|
}
|
|
if (input->bdev) {
|
|
bdput(input->bdev);
|
|
input->bdev = NULL;
|
|
}
|
|
del_gendisk(input->disk);
|
|
put_disk(input->disk);
|
|
input->disk = NULL;
|
|
is_down:
|
|
mars_power_led_off((void*)brick, true);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
//////////////// informational / statistics ///////////////
|
|
|
|
static
|
|
char *if_statistics(struct if_brick *brick, int verbose)
|
|
{
|
|
struct if_input *input = brick->inputs[0];
|
|
char *res = kmalloc(512, GFP_MARS);
|
|
int tmp1 = atomic_read(&input->total_read_count);
|
|
int tmp2 = atomic_read(&input->total_mref_read_count);
|
|
int tmp3 = atomic_read(&input->total_write_count);
|
|
int tmp4 = atomic_read(&input->total_mref_write_count);
|
|
if (!res)
|
|
return NULL;
|
|
sprintf(res, "total reads = %d mref_reads = %d (%d%%) writes = %d mref_writes = %d (%d%%) empty = %d | plugged = %d flying = %d (reads = %d writes = %d)\n",
|
|
tmp1,
|
|
tmp2,
|
|
tmp1 ? tmp2 * 100 / tmp1 : 0,
|
|
tmp3,
|
|
tmp4,
|
|
tmp3 ? tmp4 * 100 / tmp3 : 0,
|
|
atomic_read(&input->total_empty_count),
|
|
atomic_read(&input->plugged_count),
|
|
atomic_read(&input->flying_count),
|
|
atomic_read(&input->read_flying_count),
|
|
atomic_read(&input->write_flying_count));
|
|
return res;
|
|
}
|
|
|
|
static
|
|
void if_reset_statistics(struct if_brick *brick)
|
|
{
|
|
struct if_input *input = brick->inputs[0];
|
|
atomic_set(&input->total_read_count, 0);
|
|
atomic_set(&input->total_write_count, 0);
|
|
atomic_set(&input->total_empty_count, 0);
|
|
atomic_set(&input->total_mref_read_count, 0);
|
|
atomic_set(&input->total_mref_write_count, 0);
|
|
}
|
|
|
|
////////////////// own brick / input / output operations //////////////////
|
|
|
|
// none
|
|
|
|
//////////////// object / aspect constructors / destructors ///////////////
|
|
|
|
static int if_mref_aspect_init_fn(struct generic_aspect *_ini, void *_init_data)
|
|
{
|
|
struct if_mref_aspect *ini = (void*)_ini;
|
|
INIT_LIST_HEAD(&ini->plug_head);
|
|
INIT_LIST_HEAD(&ini->hash_head);
|
|
return 0;
|
|
}
|
|
|
|
static void if_mref_aspect_exit_fn(struct generic_aspect *_ini, void *_init_data)
|
|
{
|
|
struct if_mref_aspect *ini = (void*)_ini;
|
|
CHECK_HEAD_EMPTY(&ini->plug_head);
|
|
CHECK_HEAD_EMPTY(&ini->hash_head);
|
|
}
|
|
|
|
MARS_MAKE_STATICS(if);
|
|
|
|
//////////////////////// constructors / destructors ////////////////////////
|
|
|
|
static int if_brick_construct(struct if_brick *brick)
|
|
{
|
|
struct if_output *hidden = &brick->hidden_output;
|
|
_if_output_init(brick, hidden, "internal");
|
|
return 0;
|
|
}
|
|
|
|
static int if_brick_destruct(struct if_brick *brick)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static int if_input_construct(struct if_input *input)
|
|
{
|
|
int i;
|
|
for (i = 0; i < IF_HASH_MAX; i++) {
|
|
spin_lock_init(&input->hash_lock[i]);
|
|
INIT_LIST_HEAD(&input->hash_table[i]);
|
|
}
|
|
INIT_LIST_HEAD(&input->plug_anchor);
|
|
sema_init(&input->kick_sem, 1);
|
|
spin_lock_init(&input->req_lock);
|
|
atomic_set(&input->open_count, 0);
|
|
atomic_set(&input->flying_count, 0);
|
|
atomic_set(&input->plugged_count, 0);
|
|
#ifdef USE_TIMER
|
|
init_timer(&input->timer);
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
static int if_input_destruct(struct if_input *input)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static int if_output_construct(struct if_output *output)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
///////////////////////// static structs ////////////////////////
|
|
|
|
static struct if_brick_ops if_brick_ops = {
|
|
.brick_switch = if_switch,
|
|
.brick_statistics = if_statistics,
|
|
.reset_statistics = if_reset_statistics,
|
|
};
|
|
|
|
static struct if_output_ops if_output_ops = {
|
|
.make_object_layout = if_make_object_layout,
|
|
};
|
|
|
|
const struct if_input_type if_input_type = {
|
|
.type_name = "if_input",
|
|
.input_size = sizeof(struct if_input),
|
|
.input_construct = &if_input_construct,
|
|
.input_destruct = &if_input_destruct,
|
|
};
|
|
|
|
static const struct if_input_type *if_input_types[] = {
|
|
&if_input_type,
|
|
};
|
|
|
|
const struct if_output_type if_output_type = {
|
|
.type_name = "if_output",
|
|
.output_size = sizeof(struct if_output),
|
|
.master_ops = &if_output_ops,
|
|
.output_construct = &if_output_construct,
|
|
.aspect_types = if_aspect_types,
|
|
.layout_code = {
|
|
[BRICK_OBJ_MREF] = LAYOUT_ALL,
|
|
}
|
|
};
|
|
|
|
static const struct if_output_type *if_output_types[] = {
|
|
&if_output_type,
|
|
};
|
|
|
|
|
|
const struct if_brick_type if_brick_type = {
|
|
.type_name = "if_brick",
|
|
.brick_size = sizeof(struct if_brick),
|
|
.max_inputs = 1,
|
|
.max_outputs = 0,
|
|
.master_ops = &if_brick_ops,
|
|
.default_input_types = if_input_types,
|
|
.default_output_types = if_output_types,
|
|
.brick_construct = &if_brick_construct,
|
|
.brick_destruct = &if_brick_destruct,
|
|
};
|
|
EXPORT_SYMBOL_GPL(if_brick_type);
|
|
|
|
////////////////// module init stuff /////////////////////////
|
|
|
|
static void __exit exit_if(void)
|
|
{
|
|
int status;
|
|
MARS_INF("exit_if()\n");
|
|
status = if_unregister_brick_type();
|
|
unregister_blkdev(MARS_MAJOR, "mars");
|
|
}
|
|
|
|
static int __init init_if(void)
|
|
{
|
|
int status;
|
|
|
|
(void)if_aspect_types; // not used, shut up gcc
|
|
|
|
MARS_INF("init_if()\n");
|
|
status = register_blkdev(MARS_MAJOR, "mars");
|
|
if (status)
|
|
return status;
|
|
status = if_register_brick_type();
|
|
if (status)
|
|
goto err_device;
|
|
return status;
|
|
err_device:
|
|
MARS_ERR("init_if() status=%d\n", status);
|
|
exit_if();
|
|
return status;
|
|
}
|
|
|
|
MODULE_DESCRIPTION("MARS if");
|
|
MODULE_AUTHOR("Thomas Schoebel-Theuer <tst@1und1.de>");
|
|
MODULE_LICENSE("GPL");
|
|
|
|
module_init(init_if);
|
|
module_exit(exit_if);
|