mars/mars_if.h

88 lines
1.9 KiB
C

// (c) 2010 Thomas Schoebel-Theuer / 1&1 Internet AG
#ifndef MARS_IF_H
#define MARS_IF_H
#include <linux/semaphore.h>
#define HT_SHIFT 6 //????
#define MARS_MAX_SEGMENT_SIZE (1U << (9+HT_SHIFT))
#define MAX_BIO 32
#define IF_HASH_MAX 2048
#define IF_HASH_CHUNK (PAGE_SIZE * 32)
//#define USE_TIMER (HZ/10) // use this ONLY for debugging
/* I don't want to enhance / intrude into struct bio for compatibility reasons
* (support for a variety of kernel versions).
* The following is just a silly workaround which could be removed again.
*/
struct bio_wrapper {
struct bio *bio;
atomic_t bi_comp_cnt;
};
struct if_mref_aspect {
GENERIC_ASPECT(mref);
struct list_head plug_head;
struct list_head hash_head;
int hash_index;
int bio_count;
int current_len;
int max_len;
bool is_kmapped;
struct page *orig_page;
struct bio_wrapper *orig_biow[MAX_BIO];
struct if_input *input;
};
struct if_input {
MARS_INPUT(if);
// TODO: move this to if_brick (better systematics)
struct list_head plug_anchor;
struct request_queue *q;
struct gendisk *disk;
struct block_device *bdev;
#ifdef USE_TIMER
struct timer_list timer;
#endif
atomic_t open_count;
atomic_t plugged_count;
atomic_t flying_count;
// only for statistics
atomic_t read_flying_count;
atomic_t write_flying_count;
atomic_t total_reada_count;
atomic_t total_read_count;
atomic_t total_write_count;
atomic_t total_empty_count;
atomic_t total_mref_read_count;
atomic_t total_mref_write_count;
spinlock_t req_lock;
struct semaphore kick_sem;
struct generic_object_layout mref_object_layout;
struct mars_info info;
spinlock_t hash_lock[IF_HASH_MAX];
struct list_head hash_table[IF_HASH_MAX];
};
struct if_output {
MARS_OUTPUT(if);
};
struct if_brick {
MARS_BRICK(if);
// parameters
int max_plugged;
int readahead;
bool skip_sync;
// inspectable
// private
struct semaphore switch_sem;
};
MARS_TYPES(if);
#endif