static void do_request(void) { int i, r; if (sorting) return; if (!this_request) { do_hd = NULL; return; } if (this_request->cmd == WIN_WRITE) { hd_out(this_request->hd, this_request->nsector, this_request->sector, this_request->head, this_request->cyl, this_request->cmd, &write_intr); for (i = 0; i < 3000 && !(r = inb_p(HD_STATUS) & DRQ_STAT); i++) /* nothing */; if (!r) { reset_hd(this_request->hd); return; } port_write(HD_DATA, this_request->bh->b_data + 512*(this_request->nsector & 1), 256); } else if (this_request->cmd == WIN_READ) { hd_out(this_request->hd, this_request->nsector, this_request->sector, this_request->head, this_request->cyl, this_request->cmd, &read_intr); } else panic("unknow hd-command"); }
static void bad_rw_intr(void) { int i = CURRENT_DEV; if (CURRENT->errors++ >= MAX_ERRORS) end_request(0); reset_hd(i); }
void do_hd_request(void) { int i,r; unsigned int block,dev; unsigned int sec,head,cyl; unsigned int nsect; INIT_REQUEST; dev = MINOR(CURRENT->dev); block = CURRENT->sector; if (dev >= (NR_HD<<6) || block+2 > hd[dev].nr_sects) { end_request(0); goto repeat; } block += hd[dev].start_sect; dev >>= 6; sec = block % hd_info[dev].sect; block /= hd_info[dev].sect; head = block % hd_info[dev].head; cyl = block / hd_info[dev].head; sec++; nsect = CURRENT->nr_sectors; if (reset) { recalibrate = 1; reset_hd(); return; } if (recalibrate) { recalibrate = 0; hd_out(dev,hd_info[CURRENT_DEV].sect,0,0,0, WIN_RESTORE,&recal_intr); if (reset) goto repeat; return; } if (CURRENT->cmd == WRITE) { hd_out(dev,nsect,sec,head,cyl,WIN_WRITE,&write_intr); if (reset) goto repeat; for(i=0 ; i<10000 && !(r=inb_p(HD_STATUS)&DRQ_STAT) ; i++) /* nothing */ ; if (!r) { bad_rw_intr(); goto repeat; } port_write(HD_DATA,CURRENT->buffer,256); } else if (CURRENT->cmd == READ) { hd_out(dev,nsect,sec,head,cyl,WIN_READ,&read_intr); if (reset) goto repeat; } else panic("unknown hd-command"); }
static void bad_rw_intr(void) { int i = this_request->hd; if (this_request->errors++ >= MAX_ERRORS) { this_request->bh->b_uptodate = 0; unlock_buffer(this_request->bh); wake_up(&wait_for_request); this_request->hd = -1; this_request = this_request->next; } reset_hd(i); }
/* * The driver enables interrupts as much as possible. In order to do this, * (a) the device-interrupt is disabled before entering hd_request(), * and (b) the timeout-interrupt is disabled before the sti(). * * Interrupts are still masked (by default) whenever we are exchanging * data/cmds with a drive, because some drives seem to have very poor * tolerance for latency during I/O. The IDE driver has support to unmask * interrupts for non-broken hardware, so use that driver if required. */ static void hd_request(void) { unsigned int block, nsect, sec, track, head, cyl; struct hd_i_struct *disk; struct request *req; if (do_hd) return; repeat: del_timer(&device_timer); if (!hd_req) { hd_req = blk_fetch_request(hd_queue); if (!hd_req) { do_hd = NULL; return; } } req = hd_req; if (reset) { reset_hd(); return; } disk = req->rq_disk->private_data; block = blk_rq_pos(req); nsect = blk_rq_sectors(req); if (block >= get_capacity(req->rq_disk) || ((block+nsect) > get_capacity(req->rq_disk))) { printk("%s: bad access: block=%d, count=%d\n", req->rq_disk->disk_name, block, nsect); hd_end_request_cur(-EIO); goto repeat; } if (disk->special_op) { if (do_special_op(disk, req)) goto repeat; return; } sec = block % disk->sect + 1; track = block / disk->sect; head = track % disk->head; cyl = track / disk->head; #ifdef DEBUG printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p\n", req->rq_disk->disk_name, req_data_dir(req) == READ ? "read" : "writ", cyl, head, sec, nsect, req->buffer); #endif <<<<<<< HEAD
// 处理请求队列里面所有请求 void do_hd_request(void) { int i,r = 0; unsigned int block,dev; unsigned int sec,head,cyl; unsigned int nsect; INIT_REQUEST; dev = MINOR(CURRENT->dev); block = CURRENT->sector; if (dev >= 5*NR_HD || block+2 > hd[dev].nr_sects) { end_request(0); goto repeat; } block += hd[dev].start_sect; dev /= 5; __asm__("divl %4":"=a" (block),"=d" (sec):"0" (block),"1" (0), "r" (hd_info[dev].sect)); __asm__("divl %4":"=a" (cyl),"=d" (head):"0" (block),"1" (0), "r" (hd_info[dev].head)); sec++; nsect = CURRENT->nr_sectors; if (reset) { reset = 0; recalibrate = 1; reset_hd(CURRENT_DEV); return; } if (recalibrate) { recalibrate = 0; hd_out(dev,hd_info[CURRENT_DEV].sect,0,0,0, WIN_RESTORE,&recal_intr); return; } if (CURRENT->cmd == WRITE) { hd_out(dev,nsect,sec,head,cyl,WIN_WRITE,&write_intr); for(i=0 ; i<3000 && !(r=inb_p(HD_STATUS)&DRQ_STAT) ; i++) /* nothing */ ; if (!r) { bad_rw_intr(); goto repeat; } port_write(HD_DATA,CURRENT->buffer,256); } else if (CURRENT->cmd == READ) { // 设置回调函数 read_intr 直接返回 hd_out(dev,nsect,sec,head,cyl,WIN_READ,&read_intr); } else panic("unknown hd-command"); }
/* * The driver enables interrupts as much as possible. In order to do this, * (a) the device-interrupt is disabled before entering hd_request(), * and (b) the timeout-interrupt is disabled before the sti(). * * Interrupts are still masked (by default) whenever we are exchanging * data/cmds with a drive, because some drives seem to have very poor * tolerance for latency during I/O. The IDE driver has support to unmask * interrupts for non-broken hardware, so use that driver if required. */ static void hd_request(void) { unsigned int block, nsect, sec, track, head, cyl; struct hd_i_struct *disk; struct request *req; if (do_hd) return; repeat: del_timer(&device_timer); local_irq_enable(); req = CURRENT; if (!req) { do_hd = NULL; return; } if (reset) { local_irq_disable(); reset_hd(); return; } disk = req->rq_disk->private_data; block = req->sector; nsect = req->nr_sectors; if (block >= get_capacity(req->rq_disk) || ((block+nsect) > get_capacity(req->rq_disk))) { printk("%s: bad access: block=%d, count=%d\n", req->rq_disk->disk_name, block, nsect); end_request(req, 0); goto repeat; } if (disk->special_op) { if (do_special_op(disk, req)) goto repeat; return; } sec = block % disk->sect + 1; track = block / disk->sect; head = track % disk->head; cyl = track / disk->head; #ifdef DEBUG printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p\n", req->rq_disk->disk_name, (req->cmd == READ)?"read":"writ", cyl, head, sec, nsect, req->buffer); #endif if (blk_fs_request(req)) { switch (rq_data_dir(req)) { case READ: hd_out(disk,nsect,sec,head,cyl,WIN_READ,&read_intr); if (reset) goto repeat; break; case WRITE: hd_out(disk,nsect,sec,head,cyl,WIN_WRITE,&write_intr); if (reset) goto repeat; if (wait_DRQ()) { bad_rw_intr(); goto repeat; } outsw(HD_DATA,req->buffer,256); break; default: printk("unknown hd-command\n"); end_request(req, 0); break; } } }
void do_hd_request(void) { int i, r = 0; unsigned int start_sector, dev, partition; unsigned int start_sec, head, cyl; unsigned int nsect; CHECK_REQUEST; partition = MINOR(CURRENT_REQ->dev); /* get partition */ start_sector = CURRENT_REQ->start_sector; nsect = CURRENT_REQ->nr_sectors; /* need to check if nsect is exceed the partition limit or not */ if (partition >= 5 * NR_HD || nsect > hd[partition].nr_sects) { end_request(0); goto repeat; /* repeat defined in blk.h */ } start_sector += hd[partition].start_sect; dev = partition / 5; /* get cyl, head, start_sec number according start_sector */ /* div result: EAX = Quotient, EDX = Remainder */ /* * start_sector / sect nrs per track = total track number(start_sector) * ... remainder sector number(start_sec) */ __asm__("divl %4" :"=a" (start_sector), "=d" (start_sec) :"0" (start_sector), "1" (0), "r" (hd_info[dev].sect)); /* totoal track number / total head nrs = cylinder number(cyl) * ... head nr(head) */ __asm__("divl %4" :"=a" (cyl), "=d" (head) :"0" (start_sector), "1" (0), "r" (hd_info[dev].head)); start_sec++; if (reset) { reset = 0; recalibrate = 1; reset_hd(CURRENT_DEV); return; } if (recalibrate) { recalibrate = 0; hd_out(dev, hd_info[CURRENT_DEV].sect, 0, 0, 0, WIN_RESTORE, recal_intr); return; } if (CURRENT_REQ->cmd == WRITE) { hd_out(dev, nsect, start_sec, head, cyl, WIN_WRITE, write_intr); /* wait DRQ_STAT signal */ for(i = 0; i < 3000 && !(r = inb_p(HD_STATUS) & DRQ_STAT); i++) /* nothing */ ; if (!r) { bad_rw_intr(); goto repeat; } /* write 512 byte (1 sector) to HD */ port_write(HD_DATA, CURRENT_REQ->buffer, 256); } else if (CURRENT_REQ->cmd == READ) { hd_out(dev, nsect, start_sec, head, cyl, WIN_READ, read_intr); } else { panic("unknown hd-command"); } }
/* * The driver enables interrupts as much as possible. In order to do this, * (a) the device-interrupt is disabled before entering hd_request(), * and (b) the timeout-interrupt is disabled before the sti(). * * Interrupts are still masked (by default) whenever we are exchanging * data/cmds with a drive, because some drives seem to have very poor * tolerance for latency during I/O. The IDE driver has support to unmask * interrupts for non-broken hardware, so use that driver if required. */ static void hd_request(void) { unsigned int block, nsect, sec, track, head, cyl; struct hd_i_struct *disk; struct request *req; if (do_hd) return; repeat: del_timer(&device_timer); if (!hd_req) { hd_req = blk_fetch_request(hd_queue); if (!hd_req) { do_hd = NULL; return; } } req = hd_req; if (reset) { reset_hd(); return; } disk = req->rq_disk->private_data; block = blk_rq_pos(req); nsect = blk_rq_sectors(req); if (block >= get_capacity(req->rq_disk) || ((block+nsect) > get_capacity(req->rq_disk))) { printk("%s: bad access: block=%d, count=%d\n", req->rq_disk->disk_name, block, nsect); hd_end_request_cur(-EIO); goto repeat; } if (disk->special_op) { if (do_special_op(disk, req)) goto repeat; return; } sec = block % disk->sect + 1; track = block / disk->sect; head = track % disk->head; cyl = track / disk->head; #ifdef DEBUG printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p\n", req->rq_disk->disk_name, req_data_dir(req) == READ ? "read" : "writ", cyl, head, sec, nsect, req->buffer); #endif if (req->cmd_type == REQ_TYPE_FS) { switch (rq_data_dir(req)) { case READ: hd_out(disk, nsect, sec, head, cyl, ATA_CMD_PIO_READ, &read_intr); if (reset) goto repeat; break; case WRITE: hd_out(disk, nsect, sec, head, cyl, ATA_CMD_PIO_WRITE, &write_intr); if (reset) goto repeat; if (wait_DRQ()) { bad_rw_intr(); goto repeat; } outsw(HD_DATA, req->buffer, 256); break; default: printk("unknown hd-command\n"); hd_end_request_cur(-EIO); break; } } }