2 * The low performance USB storage driver (ub).
4 * Copyright (c) 1999, 2000 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
5 * Copyright (C) 2004 Pete Zaitcev (zaitcev@yahoo.com)
7 * This work is a part of Linux kernel, is derived from it,
8 * and is not licensed separately. See file COPYING for details.
10 * TODO (sorted by decreasing priority)
11 * -- set readonly flag for CDs, set removable flag for CF readers
12 * -- do inquiry and verify we got a disk and not a tape (for LUN mismatch)
13 * -- special case some senses, e.g. 3a/0 -> no media present, reduce retries
14 * -- verify the 13 conditions and do bulk resets
15 * -- kill last_pipe and simply do two-state clearing on both pipes
17 * -- move top_sense and work_bcs into separate allocations (if they survive)
18 * for cache purists and esoteric architectures.
19 * -- Allocate structure for LUN 0 before the first ub_sync_tur, avoid NULL. ?
20 * -- prune comments, they are too volumnous
21 * -- Exterminate P3 printks
23 * -- Redo "benh's retries", perhaps have spin-up code to handle them. V:D=?
24 * -- CLEAR, CLR2STS, CLRRS seem to be ripe for refactoring.
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/usb.h>
29 #include <linux/usb_usual.h>
30 #include <linux/blkdev.h>
31 #include <linux/devfs_fs_kernel.h>
32 #include <linux/timer.h>
33 #include <scsi/scsi.h>
36 #define DEVFS_NAME DRV_NAME
41 * The command state machine is the key model for understanding of this driver.
43 * The general rule is that all transitions are done towards the bottom
44 * of the diagram, thus preventing any loops.
46 * An exception to that is how the STAT state is handled. A counter allows it
47 * to be re-entered along the path marked with [C].
53 * ub_scsi_cmd_start fails ->--------------------------------------\
60 * was -EPIPE -->-------------------------------->! CLEAR ! !
63 * was error -->------------------------------------- ! --------->\
65 * /--<-- cmd->dir == NONE ? ! !
72 * ! was -EPIPE -->--------------->! CLR2STS ! ! !
75 * ! ! was error -->---- ! --------->\
76 * ! was error -->--------------------- ! ------------- ! --------->\
79 * \--->+--------+ ! ! !
80 * ! STAT !<--------------------------/ ! !
83 * [C] was -EPIPE -->-----------\ ! !
85 * +<---- len == 0 ! ! !
87 * ! was error -->--------------------------------------!---------->\
89 * +<---- bad CSW ! ! !
90 * +<---- bad tag ! ! !
96 * \------- ! --------------------[C]--------\ ! !
98 * cmd->error---\ +--------+ ! !
99 * ! +--------------->! SENSE !<----------/ !
100 * STAT_FAIL----/ +--------+ !
103 * \--------------------------------\--------------------->! DONE !
108 * This many LUNs per USB device.
109 * Every one of them takes a host, see UB_MAX_HOSTS.
111 #define UB_MAX_LUNS 9
116 #define UB_PARTS_PER_LUN 8
118 #define UB_MAX_CDB_SIZE 16 /* Corresponds to Bulk */
120 #define UB_SENSE_SIZE 18
125 /* command block wrapper */
126 struct bulk_cb_wrap {
127 __le32 Signature; /* contains 'USBC' */
128 u32 Tag; /* unique per command id */
129 __le32 DataTransferLength; /* size of data */
130 u8 Flags; /* direction in bit 0 */
132 u8 Length; /* of of the CDB */
133 u8 CDB[UB_MAX_CDB_SIZE]; /* max command */
136 #define US_BULK_CB_WRAP_LEN 31
137 #define US_BULK_CB_SIGN 0x43425355 /*spells out USBC */
138 #define US_BULK_FLAG_IN 1
139 #define US_BULK_FLAG_OUT 0
141 /* command status wrapper */
142 struct bulk_cs_wrap {
143 __le32 Signature; /* should = 'USBS' */
144 u32 Tag; /* same as original command */
145 __le32 Residue; /* amount not transferred */
146 u8 Status; /* see below */
149 #define US_BULK_CS_WRAP_LEN 13
150 #define US_BULK_CS_SIGN 0x53425355 /* spells out 'USBS' */
151 #define US_BULK_STAT_OK 0
152 #define US_BULK_STAT_FAIL 1
153 #define US_BULK_STAT_PHASE 2
155 /* bulk-only class specific requests */
156 #define US_BULK_RESET_REQUEST 0xff
157 #define US_BULK_GET_MAX_LUN 0xfe
163 #define UB_MAX_REQ_SG 9 /* cdrecord requires 32KB and maybe a header */
164 #define UB_MAX_SECTORS 64
167 * A second is more than enough for a 32K transfer (UB_MAX_SECTORS)
168 * even if a webcam hogs the bus, but some devices need time to spin up.
170 #define UB_URB_TIMEOUT (HZ*2)
171 #define UB_DATA_TIMEOUT (HZ*5) /* ZIP does spin-ups in the data phase */
172 #define UB_STAT_TIMEOUT (HZ*5) /* Same spinups and eject for a dataless cmd. */
173 #define UB_CTRL_TIMEOUT (HZ/2) /* 500ms ought to be enough to clear a stall */
176 * An instance of a SCSI command in transit.
178 #define UB_DIR_NONE 0
179 #define UB_DIR_READ 1
180 #define UB_DIR_ILLEGAL2 2
181 #define UB_DIR_WRITE 3
184 #define UB_DIR_CHAR(c) (((c)==UB_DIR_WRITE)? 'w': \
185 (((c)==UB_DIR_READ)? 'r': 'n'))
187 enum ub_scsi_cmd_state {
188 UB_CMDST_INIT, /* Initial state */
189 UB_CMDST_CMD, /* Command submitted */
190 UB_CMDST_DATA, /* Data phase */
191 UB_CMDST_CLR2STS, /* Clearing before requesting status */
192 UB_CMDST_STAT, /* Status phase */
193 UB_CMDST_CLEAR, /* Clearing a stall (halt, actually) */
194 UB_CMDST_CLRRS, /* Clearing before retrying status */
195 UB_CMDST_SENSE, /* Sending Request Sense */
196 UB_CMDST_DONE /* Final state */
200 unsigned char cdb[UB_MAX_CDB_SIZE];
201 unsigned char cdb_len;
203 unsigned char dir; /* 0 - none, 1 - read, 3 - write. */
204 enum ub_scsi_cmd_state state;
206 struct ub_scsi_cmd *next;
208 int error; /* Return code - valid upon done */
209 unsigned int act_len; /* Return size */
210 unsigned char key, asc, ascq; /* May be valid if error==-EIO */
212 int stat_count; /* Retries getting status. */
214 unsigned int len; /* Requested length */
215 unsigned int current_sg;
216 unsigned int nsg; /* sgv[nsg] */
217 struct scatterlist sgv[UB_MAX_REQ_SG];
220 void (*done)(struct ub_dev *, struct ub_scsi_cmd *);
226 unsigned int current_try;
227 unsigned int nsg; /* sgv[nsg] */
228 struct scatterlist sgv[UB_MAX_REQ_SG];
234 unsigned long nsec; /* Linux size - 512 byte sectors */
235 unsigned int bsize; /* Linux hardsect_size */
236 unsigned int bshift; /* Shift between 512 and hard sects */
240 * This is a direct take-off from linux/include/completion.h
241 * The difference is that I do not wait on this thing, just poll.
242 * When I want to wait (ub_probe), I just use the stock completion.
244 * Note that INIT_COMPLETION takes no lock. It is correct. But why
245 * in the bloody hell that thing takes struct instead of pointer to struct
246 * is quite beyond me. I just copied it from the stock completion.
248 struct ub_completion {
253 static inline void ub_init_completion(struct ub_completion *x)
256 spin_lock_init(&x->lock);
259 #define UB_INIT_COMPLETION(x) ((x).done = 0)
261 static void ub_complete(struct ub_completion *x)
265 spin_lock_irqsave(&x->lock, flags);
267 spin_unlock_irqrestore(&x->lock, flags);
270 static int ub_is_completed(struct ub_completion *x)
275 spin_lock_irqsave(&x->lock, flags);
277 spin_unlock_irqrestore(&x->lock, flags);
283 struct ub_scsi_cmd_queue {
285 struct ub_scsi_cmd *head, *tail;
289 * The block device instance (one per LUN).
293 struct list_head link;
294 struct gendisk *disk;
295 int id; /* Host index */
296 int num; /* LUN number */
299 int changed; /* Media was changed */
303 struct ub_request urq;
305 /* Use Ingo's mempool if or when we have more than one command. */
307 * Currently we never need more than one command for the whole device.
308 * However, giving every LUN a command is a cheap and automatic way
309 * to enforce fairness between them.
312 struct ub_scsi_cmd cmdv[1];
314 struct ub_capacity capacity;
318 * The USB device instance.
322 atomic_t poison; /* The USB device is disconnected */
323 int openc; /* protected by ub_lock! */
324 /* kref is too implicit for our taste */
325 int reset; /* Reset is running */
328 struct usb_device *dev;
329 struct usb_interface *intf;
331 struct list_head luns;
333 unsigned int send_bulk_pipe; /* cached pipe values */
334 unsigned int recv_bulk_pipe;
335 unsigned int send_ctrl_pipe;
336 unsigned int recv_ctrl_pipe;
338 struct tasklet_struct tasklet;
340 struct ub_scsi_cmd_queue cmd_queue;
341 struct ub_scsi_cmd top_rqs_cmd; /* REQUEST SENSE */
342 unsigned char top_sense[UB_SENSE_SIZE];
344 struct ub_completion work_done;
346 struct timer_list work_timer;
347 int last_pipe; /* What might need clearing */
348 __le32 signature; /* Learned signature */
349 struct bulk_cb_wrap work_bcb;
350 struct bulk_cs_wrap work_bcs;
351 struct usb_ctrlrequest work_cr;
353 struct work_struct reset_work;
354 wait_queue_head_t reset_wait;
361 static void ub_cleanup(struct ub_dev *sc);
362 static int ub_request_fn_1(struct ub_lun *lun, struct request *rq);
363 static void ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
364 struct ub_scsi_cmd *cmd, struct ub_request *urq);
365 static void ub_cmd_build_packet(struct ub_dev *sc, struct ub_lun *lun,
366 struct ub_scsi_cmd *cmd, struct ub_request *urq);
367 static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
368 static void ub_end_rq(struct request *rq, int uptodate);
369 static int ub_rw_cmd_retry(struct ub_dev *sc, struct ub_lun *lun,
370 struct ub_request *urq, struct ub_scsi_cmd *cmd);
371 static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
372 static void ub_urb_complete(struct urb *urb, struct pt_regs *pt);
373 static void ub_scsi_action(unsigned long _dev);
374 static void ub_scsi_dispatch(struct ub_dev *sc);
375 static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
376 static void ub_data_start(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
377 static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc);
378 static int __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
379 static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
380 static void ub_state_stat_counted(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
381 static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
382 static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
384 static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd);
385 static void ub_reset_enter(struct ub_dev *sc, int try);
386 static void ub_reset_task(void *arg);
387 static int ub_sync_tur(struct ub_dev *sc, struct ub_lun *lun);
388 static int ub_sync_read_cap(struct ub_dev *sc, struct ub_lun *lun,
389 struct ub_capacity *ret);
390 static int ub_sync_reset(struct ub_dev *sc);
391 static int ub_probe_clear_stall(struct ub_dev *sc, int stalled_pipe);
392 static int ub_probe_lun(struct ub_dev *sc, int lnum);
396 #ifdef CONFIG_USB_LIBUSUAL
398 #define ub_usb_ids storage_usb_ids
401 static struct usb_device_id ub_usb_ids[] = {
402 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_SCSI, US_PR_BULK) },
406 MODULE_DEVICE_TABLE(usb, ub_usb_ids);
407 #endif /* CONFIG_USB_LIBUSUAL */
410 * Find me a way to identify "next free minor" for add_disk(),
411 * and the array disappears the next day. However, the number of
412 * hosts has something to do with the naming and /proc/partitions.
413 * This has to be thought out in detail before changing.
414 * If UB_MAX_HOST was 1000, we'd use a bitmap. Or a better data structure.
416 #define UB_MAX_HOSTS 26
417 static char ub_hostv[UB_MAX_HOSTS];
419 #define UB_QLOCK_NUM 5
420 static spinlock_t ub_qlockv[UB_QLOCK_NUM];
421 static int ub_qlock_next = 0;
423 static DEFINE_SPINLOCK(ub_lock); /* Locks globals and ->openc */
428 * This also stores the host for indexing by minor, which is somewhat dirty.
430 static int ub_id_get(void)
435 spin_lock_irqsave(&ub_lock, flags);
436 for (i = 0; i < UB_MAX_HOSTS; i++) {
437 if (ub_hostv[i] == 0) {
439 spin_unlock_irqrestore(&ub_lock, flags);
443 spin_unlock_irqrestore(&ub_lock, flags);
447 static void ub_id_put(int id)
451 if (id < 0 || id >= UB_MAX_HOSTS) {
452 printk(KERN_ERR DRV_NAME ": bad host ID %d\n", id);
456 spin_lock_irqsave(&ub_lock, flags);
457 if (ub_hostv[id] == 0) {
458 spin_unlock_irqrestore(&ub_lock, flags);
459 printk(KERN_ERR DRV_NAME ": freeing free host ID %d\n", id);
463 spin_unlock_irqrestore(&ub_lock, flags);
467 * This is necessitated by the fact that blk_cleanup_queue does not
468 * necesserily destroy the queue. Instead, it may merely decrease q->refcnt.
469 * Since our blk_init_queue() passes a spinlock common with ub_dev,
470 * we have life time issues when ub_cleanup frees ub_dev.
472 static spinlock_t *ub_next_lock(void)
477 spin_lock_irqsave(&ub_lock, flags);
478 ret = &ub_qlockv[ub_qlock_next];
479 ub_qlock_next = (ub_qlock_next + 1) % UB_QLOCK_NUM;
480 spin_unlock_irqrestore(&ub_lock, flags);
485 * Downcount for deallocation. This rides on two assumptions:
486 * - once something is poisoned, its refcount cannot grow
487 * - opens cannot happen at this time (del_gendisk was done)
488 * If the above is true, we can drop the lock, which we need for
489 * blk_cleanup_queue(): the silly thing may attempt to sleep.
490 * [Actually, it never needs to sleep for us, but it calls might_sleep()]
492 static void ub_put(struct ub_dev *sc)
496 spin_lock_irqsave(&ub_lock, flags);
498 if (sc->openc == 0 && atomic_read(&sc->poison)) {
499 spin_unlock_irqrestore(&ub_lock, flags);
502 spin_unlock_irqrestore(&ub_lock, flags);
507 * Final cleanup and deallocation.
509 static void ub_cleanup(struct ub_dev *sc)
515 while (!list_empty(&sc->luns)) {
517 lun = list_entry(p, struct ub_lun, link);
520 /* I don't think queue can be NULL. But... Stolen from sx8.c */
521 if ((q = lun->disk->queue) != NULL)
522 blk_cleanup_queue(q);
524 * If we zero disk->private_data BEFORE put_disk, we have
525 * to check for NULL all over the place in open, release,
526 * check_media and revalidate, because the block level
527 * semaphore is well inside the put_disk.
528 * But we cannot zero after the call, because *disk is gone.
529 * The sd.c is blatantly racy in this area.
531 /* disk->private_data = NULL; */
539 usb_set_intfdata(sc->intf, NULL);
540 usb_put_intf(sc->intf);
541 usb_put_dev(sc->dev);
546 * The "command allocator".
548 static struct ub_scsi_cmd *ub_get_cmd(struct ub_lun *lun)
550 struct ub_scsi_cmd *ret;
559 static void ub_put_cmd(struct ub_lun *lun, struct ub_scsi_cmd *cmd)
561 if (cmd != &lun->cmdv[0]) {
562 printk(KERN_WARNING "%s: releasing a foreign cmd %p\n",
567 printk(KERN_WARNING "%s: releasing a free cmd\n", lun->name);
576 static void ub_cmdq_add(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
578 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
580 if (t->qlen++ == 0) {
588 if (t->qlen > t->qmax)
592 static void ub_cmdq_insert(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
594 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
596 if (t->qlen++ == 0) {
604 if (t->qlen > t->qmax)
608 static struct ub_scsi_cmd *ub_cmdq_pop(struct ub_dev *sc)
610 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
611 struct ub_scsi_cmd *cmd;
623 #define ub_cmdq_peek(sc) ((sc)->cmd_queue.head)
626 * The request function is our main entry point
629 static void ub_request_fn(request_queue_t *q)
631 struct ub_lun *lun = q->queuedata;
634 while ((rq = elv_next_request(q)) != NULL) {
635 if (ub_request_fn_1(lun, rq) != 0) {
642 static int ub_request_fn_1(struct ub_lun *lun, struct request *rq)
644 struct ub_dev *sc = lun->udev;
645 struct ub_scsi_cmd *cmd;
646 struct ub_request *urq;
649 if (atomic_read(&sc->poison) || lun->changed) {
650 blkdev_dequeue_request(rq);
655 if (lun->urq.rq != NULL)
657 if ((cmd = ub_get_cmd(lun)) == NULL)
659 memset(cmd, 0, sizeof(struct ub_scsi_cmd));
661 blkdev_dequeue_request(rq);
664 memset(urq, 0, sizeof(struct ub_request));
668 * get scatterlist from block layer
670 n_elem = blk_rq_map_sg(lun->disk->queue, rq, &urq->sgv[0]);
672 printk(KERN_INFO "%s: failed request map (%d)\n",
673 lun->name, n_elem); /* P3 */
676 if (n_elem > UB_MAX_REQ_SG) { /* Paranoia */
677 printk(KERN_WARNING "%s: request with %d segments\n",
682 sc->sg_stat[n_elem < 5 ? n_elem : 5]++;
684 if (blk_pc_request(rq)) {
685 ub_cmd_build_packet(sc, lun, cmd, urq);
687 ub_cmd_build_block(sc, lun, cmd, urq);
689 cmd->state = UB_CMDST_INIT;
691 cmd->done = ub_rw_cmd_done;
694 cmd->tag = sc->tagcnt++;
695 if (ub_submit_scsi(sc, cmd) != 0)
701 ub_put_cmd(lun, cmd);
706 static void ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
707 struct ub_scsi_cmd *cmd, struct ub_request *urq)
709 struct request *rq = urq->rq;
710 unsigned int block, nblks;
712 if (rq_data_dir(rq) == WRITE)
713 cmd->dir = UB_DIR_WRITE;
715 cmd->dir = UB_DIR_READ;
718 memcpy(cmd->sgv, urq->sgv, sizeof(struct scatterlist) * cmd->nsg);
723 * The call to blk_queue_hardsect_size() guarantees that request
724 * is aligned, but it is given in terms of 512 byte units, always.
726 block = rq->sector >> lun->capacity.bshift;
727 nblks = rq->nr_sectors >> lun->capacity.bshift;
729 cmd->cdb[0] = (cmd->dir == UB_DIR_READ)? READ_10: WRITE_10;
730 /* 10-byte uses 4 bytes of LBA: 2147483648KB, 2097152MB, 2048GB */
731 cmd->cdb[2] = block >> 24;
732 cmd->cdb[3] = block >> 16;
733 cmd->cdb[4] = block >> 8;
735 cmd->cdb[7] = nblks >> 8;
739 cmd->len = rq->nr_sectors * 512;
742 static void ub_cmd_build_packet(struct ub_dev *sc, struct ub_lun *lun,
743 struct ub_scsi_cmd *cmd, struct ub_request *urq)
745 struct request *rq = urq->rq;
747 if (rq->data_len == 0) {
748 cmd->dir = UB_DIR_NONE;
750 if (rq_data_dir(rq) == WRITE)
751 cmd->dir = UB_DIR_WRITE;
753 cmd->dir = UB_DIR_READ;
757 memcpy(cmd->sgv, urq->sgv, sizeof(struct scatterlist) * cmd->nsg);
759 memcpy(&cmd->cdb, rq->cmd, rq->cmd_len);
760 cmd->cdb_len = rq->cmd_len;
762 cmd->len = rq->data_len;
765 static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
767 struct ub_lun *lun = cmd->lun;
768 struct ub_request *urq = cmd->back;
774 if (cmd->error == 0) {
777 if (blk_pc_request(rq)) {
778 if (cmd->act_len >= rq->data_len)
781 rq->data_len -= cmd->act_len;
786 if (blk_pc_request(rq)) {
787 /* UB_SENSE_SIZE is smaller than SCSI_SENSE_BUFFERSIZE */
788 memcpy(rq->sense, sc->top_sense, UB_SENSE_SIZE);
789 rq->sense_len = UB_SENSE_SIZE;
790 if (sc->top_sense[0] != 0)
791 rq->errors = SAM_STAT_CHECK_CONDITION;
793 rq->errors = DID_ERROR << 16;
795 if (cmd->error == -EIO) {
796 if (ub_rw_cmd_retry(sc, lun, urq, cmd) == 0)
804 ub_put_cmd(lun, cmd);
805 ub_end_rq(rq, uptodate);
806 blk_start_queue(lun->disk->queue);
809 static void ub_end_rq(struct request *rq, int uptodate)
811 end_that_request_first(rq, uptodate, rq->hard_nr_sectors);
812 end_that_request_last(rq, uptodate);
815 static int ub_rw_cmd_retry(struct ub_dev *sc, struct ub_lun *lun,
816 struct ub_request *urq, struct ub_scsi_cmd *cmd)
819 if (atomic_read(&sc->poison))
822 ub_reset_enter(sc, urq->current_try);
824 if (urq->current_try >= 3)
827 /* P3 */ printk("%s: dir %c len/act %d/%d "
828 "[sense %x %02x %02x] retry %d\n",
829 sc->name, UB_DIR_CHAR(cmd->dir), cmd->len, cmd->act_len,
830 cmd->key, cmd->asc, cmd->ascq, urq->current_try);
832 memset(cmd, 0, sizeof(struct ub_scsi_cmd));
833 ub_cmd_build_block(sc, lun, cmd, urq);
835 cmd->state = UB_CMDST_INIT;
837 cmd->done = ub_rw_cmd_done;
840 cmd->tag = sc->tagcnt++;
843 return ub_submit_scsi(sc, cmd);
845 ub_cmdq_add(sc, cmd);
851 * Submit a regular SCSI operation (not an auto-sense).
853 * The Iron Law of Good Submit Routine is:
854 * Zero return - callback is done, Nonzero return - callback is not done.
857 * Host is assumed locked.
859 static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
862 if (cmd->state != UB_CMDST_INIT ||
863 (cmd->dir != UB_DIR_NONE && cmd->len == 0)) {
867 ub_cmdq_add(sc, cmd);
869 * We can call ub_scsi_dispatch(sc) right away here, but it's a little
870 * safer to jump to a tasklet, in case upper layers do something silly.
872 tasklet_schedule(&sc->tasklet);
877 * Submit the first URB for the queued command.
878 * This function does not deal with queueing in any way.
880 static int ub_scsi_cmd_start(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
882 struct bulk_cb_wrap *bcb;
888 * ``If the allocation length is eighteen or greater, and a device
889 * server returns less than eithteen bytes of data, the application
890 * client should assume that the bytes not transferred would have been
891 * zeroes had the device server returned those bytes.''
893 * We zero sense for all commands so that when a packet request
894 * fails it does not return a stale sense.
896 memset(&sc->top_sense, 0, UB_SENSE_SIZE);
898 /* set up the command wrapper */
899 bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN);
900 bcb->Tag = cmd->tag; /* Endianness is not important */
901 bcb->DataTransferLength = cpu_to_le32(cmd->len);
902 bcb->Flags = (cmd->dir == UB_DIR_READ) ? 0x80 : 0;
903 bcb->Lun = (cmd->lun != NULL) ? cmd->lun->num : 0;
904 bcb->Length = cmd->cdb_len;
906 /* copy the command payload */
907 memcpy(bcb->CDB, cmd->cdb, UB_MAX_CDB_SIZE);
909 UB_INIT_COMPLETION(sc->work_done);
911 sc->last_pipe = sc->send_bulk_pipe;
912 usb_fill_bulk_urb(&sc->work_urb, sc->dev, sc->send_bulk_pipe,
913 bcb, US_BULK_CB_WRAP_LEN, ub_urb_complete, sc);
915 /* Fill what we shouldn't be filling, because usb-storage did so. */
916 sc->work_urb.actual_length = 0;
917 sc->work_urb.error_count = 0;
918 sc->work_urb.status = 0;
920 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
921 /* XXX Clear stalls */
922 ub_complete(&sc->work_done);
926 sc->work_timer.expires = jiffies + UB_URB_TIMEOUT;
927 add_timer(&sc->work_timer);
929 cmd->state = UB_CMDST_CMD;
936 static void ub_urb_timeout(unsigned long arg)
938 struct ub_dev *sc = (struct ub_dev *) arg;
941 spin_lock_irqsave(sc->lock, flags);
942 if (!ub_is_completed(&sc->work_done))
943 usb_unlink_urb(&sc->work_urb);
944 spin_unlock_irqrestore(sc->lock, flags);
948 * Completion routine for the work URB.
950 * This can be called directly from usb_submit_urb (while we have
951 * the sc->lock taken) and from an interrupt (while we do NOT have
952 * the sc->lock taken). Therefore, bounce this off to a tasklet.
954 static void ub_urb_complete(struct urb *urb, struct pt_regs *pt)
956 struct ub_dev *sc = urb->context;
958 ub_complete(&sc->work_done);
959 tasklet_schedule(&sc->tasklet);
962 static void ub_scsi_action(unsigned long _dev)
964 struct ub_dev *sc = (struct ub_dev *) _dev;
967 spin_lock_irqsave(sc->lock, flags);
968 ub_scsi_dispatch(sc);
969 spin_unlock_irqrestore(sc->lock, flags);
972 static void ub_scsi_dispatch(struct ub_dev *sc)
974 struct ub_scsi_cmd *cmd;
977 while (!sc->reset && (cmd = ub_cmdq_peek(sc)) != NULL) {
978 if (cmd->state == UB_CMDST_DONE) {
980 (*cmd->done)(sc, cmd);
981 } else if (cmd->state == UB_CMDST_INIT) {
982 if ((rc = ub_scsi_cmd_start(sc, cmd)) == 0)
985 cmd->state = UB_CMDST_DONE;
987 if (!ub_is_completed(&sc->work_done))
989 del_timer(&sc->work_timer);
990 ub_scsi_urb_compl(sc, cmd);
995 static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
997 struct urb *urb = &sc->work_urb;
998 struct bulk_cs_wrap *bcs;
1002 if (atomic_read(&sc->poison)) {
1003 ub_state_done(sc, cmd, -ENODEV);
1007 if (cmd->state == UB_CMDST_CLEAR) {
1008 if (urb->status == -EPIPE) {
1010 * STALL while clearning STALL.
1011 * The control pipe clears itself - nothing to do.
1013 printk(KERN_NOTICE "%s: stall on control pipe\n",
1019 * We ignore the result for the halt clear.
1022 /* reset the endpoint toggle */
1023 usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
1024 usb_pipeout(sc->last_pipe), 0);
1026 ub_state_sense(sc, cmd);
1028 } else if (cmd->state == UB_CMDST_CLR2STS) {
1029 if (urb->status == -EPIPE) {
1030 printk(KERN_NOTICE "%s: stall on control pipe\n",
1036 * We ignore the result for the halt clear.
1039 /* reset the endpoint toggle */
1040 usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
1041 usb_pipeout(sc->last_pipe), 0);
1043 ub_state_stat(sc, cmd);
1045 } else if (cmd->state == UB_CMDST_CLRRS) {
1046 if (urb->status == -EPIPE) {
1047 printk(KERN_NOTICE "%s: stall on control pipe\n",
1053 * We ignore the result for the halt clear.
1056 /* reset the endpoint toggle */
1057 usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
1058 usb_pipeout(sc->last_pipe), 0);
1060 ub_state_stat_counted(sc, cmd);
1062 } else if (cmd->state == UB_CMDST_CMD) {
1063 switch (urb->status) {
1069 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1071 printk(KERN_NOTICE "%s: "
1072 "unable to submit clear (%d)\n",
1075 * This is typically ENOMEM or some other such shit.
1076 * Retrying is pointless. Just do Bad End on it...
1078 ub_state_done(sc, cmd, rc);
1081 cmd->state = UB_CMDST_CLEAR;
1083 case -ESHUTDOWN: /* unplug */
1084 case -EILSEQ: /* unplug timeout on uhci */
1085 ub_state_done(sc, cmd, -ENODEV);
1090 if (urb->actual_length != US_BULK_CB_WRAP_LEN) {
1094 if (cmd->dir == UB_DIR_NONE || cmd->nsg < 1) {
1095 ub_state_stat(sc, cmd);
1099 // udelay(125); // usb-storage has this
1100 ub_data_start(sc, cmd);
1102 } else if (cmd->state == UB_CMDST_DATA) {
1103 if (urb->status == -EPIPE) {
1104 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1106 printk(KERN_NOTICE "%s: "
1107 "unable to submit clear (%d)\n",
1109 ub_state_done(sc, cmd, rc);
1112 cmd->state = UB_CMDST_CLR2STS;
1115 if (urb->status == -EOVERFLOW) {
1117 * A babble? Failure, but we must transfer CSW now.
1119 cmd->error = -EOVERFLOW; /* A cheap trick... */
1120 ub_state_stat(sc, cmd);
1124 if (cmd->dir == UB_DIR_WRITE) {
1126 * Do not continue writes in case of a failure.
1127 * Doing so would cause sectors to be mixed up,
1128 * which is worse than sectors lost.
1130 * We must try to read the CSW, or many devices
1133 len = urb->actual_length;
1134 if (urb->status != 0 ||
1135 len != cmd->sgv[cmd->current_sg].length) {
1136 cmd->act_len += len;
1139 ub_state_stat(sc, cmd);
1145 * If an error occurs on read, we record it, and
1146 * continue to fetch data in order to avoid bubble.
1148 * As a small shortcut, we stop if we detect that
1149 * a CSW mixed into data.
1151 if (urb->status != 0)
1154 len = urb->actual_length;
1155 if (urb->status != 0 ||
1156 len != cmd->sgv[cmd->current_sg].length) {
1157 if ((len & 0x1FF) == US_BULK_CS_WRAP_LEN)
1162 cmd->act_len += urb->actual_length;
1164 if (++cmd->current_sg < cmd->nsg) {
1165 ub_data_start(sc, cmd);
1168 ub_state_stat(sc, cmd);
1170 } else if (cmd->state == UB_CMDST_STAT) {
1171 if (urb->status == -EPIPE) {
1172 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1174 printk(KERN_NOTICE "%s: "
1175 "unable to submit clear (%d)\n",
1177 ub_state_done(sc, cmd, rc);
1182 * Having a stall when getting CSW is an error, so
1183 * make sure uppper levels are not oblivious to it.
1185 cmd->error = -EIO; /* A cheap trick... */
1187 cmd->state = UB_CMDST_CLRRS;
1191 /* Catch everything, including -EOVERFLOW and other nasties. */
1192 if (urb->status != 0)
1195 if (urb->actual_length == 0) {
1196 ub_state_stat_counted(sc, cmd);
1201 * Check the returned Bulk protocol status.
1202 * The status block has to be validated first.
1205 bcs = &sc->work_bcs;
1207 if (sc->signature == cpu_to_le32(0)) {
1209 * This is the first reply, so do not perform the check.
1210 * Instead, remember the signature the device uses
1211 * for future checks. But do not allow a nul.
1213 sc->signature = bcs->Signature;
1214 if (sc->signature == cpu_to_le32(0)) {
1215 ub_state_stat_counted(sc, cmd);
1219 if (bcs->Signature != sc->signature) {
1220 ub_state_stat_counted(sc, cmd);
1225 if (bcs->Tag != cmd->tag) {
1227 * This usually happens when we disagree with the
1228 * device's microcode about something. For instance,
1229 * a few of them throw this after timeouts. They buffer
1230 * commands and reply at commands we timed out before.
1231 * Without flushing these replies we loop forever.
1233 ub_state_stat_counted(sc, cmd);
1237 len = le32_to_cpu(bcs->Residue);
1238 if (len != cmd->len - cmd->act_len) {
1240 * It is all right to transfer less, the caller has
1241 * to check. But it's not all right if the device
1242 * counts disagree with our counts.
1244 /* P3 */ printk("%s: resid %d len %d act %d\n",
1245 sc->name, len, cmd->len, cmd->act_len);
1249 switch (bcs->Status) {
1250 case US_BULK_STAT_OK:
1252 case US_BULK_STAT_FAIL:
1253 ub_state_sense(sc, cmd);
1255 case US_BULK_STAT_PHASE:
1256 /* P3 */ printk("%s: status PHASE\n", sc->name);
1259 printk(KERN_INFO "%s: unknown CSW status 0x%x\n",
1260 sc->name, bcs->Status);
1261 ub_state_done(sc, cmd, -EINVAL);
1265 /* Not zeroing error to preserve a babble indicator */
1266 if (cmd->error != 0) {
1267 ub_state_sense(sc, cmd);
1270 cmd->state = UB_CMDST_DONE;
1272 (*cmd->done)(sc, cmd);
1274 } else if (cmd->state == UB_CMDST_SENSE) {
1275 ub_state_done(sc, cmd, -EIO);
1278 printk(KERN_WARNING "%s: "
1279 "wrong command state %d\n",
1280 sc->name, cmd->state);
1281 ub_state_done(sc, cmd, -EINVAL);
1286 Bad_End: /* Little Excel is dead */
1287 ub_state_done(sc, cmd, -EIO);
1291 * Factorization helper for the command state machine:
1292 * Initiate a data segment transfer.
1294 static void ub_data_start(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1296 struct scatterlist *sg = &cmd->sgv[cmd->current_sg];
1300 UB_INIT_COMPLETION(sc->work_done);
1302 if (cmd->dir == UB_DIR_READ)
1303 pipe = sc->recv_bulk_pipe;
1305 pipe = sc->send_bulk_pipe;
1306 sc->last_pipe = pipe;
1307 usb_fill_bulk_urb(&sc->work_urb, sc->dev, pipe,
1308 page_address(sg->page) + sg->offset, sg->length,
1309 ub_urb_complete, sc);
1310 sc->work_urb.actual_length = 0;
1311 sc->work_urb.error_count = 0;
1312 sc->work_urb.status = 0;
1314 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1315 /* XXX Clear stalls */
1316 ub_complete(&sc->work_done);
1317 ub_state_done(sc, cmd, rc);
1321 sc->work_timer.expires = jiffies + UB_DATA_TIMEOUT;
1322 add_timer(&sc->work_timer);
1324 cmd->state = UB_CMDST_DATA;
1328 * Factorization helper for the command state machine:
1329 * Finish the command.
1331 static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc)
1335 cmd->state = UB_CMDST_DONE;
1337 (*cmd->done)(sc, cmd);
1341 * Factorization helper for the command state machine:
1342 * Submit a CSW read.
1344 static int __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1348 UB_INIT_COMPLETION(sc->work_done);
1350 sc->last_pipe = sc->recv_bulk_pipe;
1351 usb_fill_bulk_urb(&sc->work_urb, sc->dev, sc->recv_bulk_pipe,
1352 &sc->work_bcs, US_BULK_CS_WRAP_LEN, ub_urb_complete, sc);
1353 sc->work_urb.actual_length = 0;
1354 sc->work_urb.error_count = 0;
1355 sc->work_urb.status = 0;
1357 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1358 /* XXX Clear stalls */
1359 ub_complete(&sc->work_done);
1360 ub_state_done(sc, cmd, rc);
1364 sc->work_timer.expires = jiffies + UB_STAT_TIMEOUT;
1365 add_timer(&sc->work_timer);
1370 * Factorization helper for the command state machine:
1371 * Submit a CSW read and go to STAT state.
1373 static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1376 if (__ub_state_stat(sc, cmd) != 0)
1379 cmd->stat_count = 0;
1380 cmd->state = UB_CMDST_STAT;
1384 * Factorization helper for the command state machine:
1385 * Submit a CSW read and go to STAT state with counter (along [C] path).
1387 static void ub_state_stat_counted(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1390 if (++cmd->stat_count >= 4) {
1391 ub_state_sense(sc, cmd);
1395 if (__ub_state_stat(sc, cmd) != 0)
1398 cmd->state = UB_CMDST_STAT;
1402 * Factorization helper for the command state machine:
1403 * Submit a REQUEST SENSE and go to SENSE state.
1405 static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1407 struct ub_scsi_cmd *scmd;
1408 struct scatterlist *sg;
1411 if (cmd->cdb[0] == REQUEST_SENSE) {
1416 scmd = &sc->top_rqs_cmd;
1417 memset(scmd, 0, sizeof(struct ub_scsi_cmd));
1418 scmd->cdb[0] = REQUEST_SENSE;
1419 scmd->cdb[4] = UB_SENSE_SIZE;
1421 scmd->dir = UB_DIR_READ;
1422 scmd->state = UB_CMDST_INIT;
1425 sg->page = virt_to_page(sc->top_sense);
1426 sg->offset = (unsigned long)sc->top_sense & (PAGE_SIZE-1);
1427 sg->length = UB_SENSE_SIZE;
1428 scmd->len = UB_SENSE_SIZE;
1429 scmd->lun = cmd->lun;
1430 scmd->done = ub_top_sense_done;
1433 scmd->tag = sc->tagcnt++;
1435 cmd->state = UB_CMDST_SENSE;
1437 ub_cmdq_insert(sc, scmd);
1441 ub_state_done(sc, cmd, rc);
1445 * A helper for the command's state machine:
1446 * Submit a stall clear.
1448 static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
1452 struct usb_ctrlrequest *cr;
1455 endp = usb_pipeendpoint(stalled_pipe);
1456 if (usb_pipein (stalled_pipe))
1460 cr->bRequestType = USB_RECIP_ENDPOINT;
1461 cr->bRequest = USB_REQ_CLEAR_FEATURE;
1462 cr->wValue = cpu_to_le16(USB_ENDPOINT_HALT);
1463 cr->wIndex = cpu_to_le16(endp);
1464 cr->wLength = cpu_to_le16(0);
1466 UB_INIT_COMPLETION(sc->work_done);
1468 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
1469 (unsigned char*) cr, NULL, 0, ub_urb_complete, sc);
1470 sc->work_urb.actual_length = 0;
1471 sc->work_urb.error_count = 0;
1472 sc->work_urb.status = 0;
1474 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1475 ub_complete(&sc->work_done);
1479 sc->work_timer.expires = jiffies + UB_CTRL_TIMEOUT;
1480 add_timer(&sc->work_timer);
1486 static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd)
1488 unsigned char *sense = sc->top_sense;
1489 struct ub_scsi_cmd *cmd;
1492 * Find the command which triggered the unit attention or a check,
1493 * save the sense into it, and advance its state machine.
1495 if ((cmd = ub_cmdq_peek(sc)) == NULL) {
1496 printk(KERN_WARNING "%s: sense done while idle\n", sc->name);
1499 if (cmd != scmd->back) {
1500 printk(KERN_WARNING "%s: "
1501 "sense done for wrong command 0x%x\n",
1502 sc->name, cmd->tag);
1505 if (cmd->state != UB_CMDST_SENSE) {
1506 printk(KERN_WARNING "%s: "
1507 "sense done with bad cmd state %d\n",
1508 sc->name, cmd->state);
1513 * Ignoring scmd->act_len, because the buffer was pre-zeroed.
1515 cmd->key = sense[2] & 0x0F;
1516 cmd->asc = sense[12];
1517 cmd->ascq = sense[13];
1519 ub_scsi_urb_compl(sc, cmd);
1524 * XXX Move usb_reset_device to khubd. Hogging kevent is not a good thing.
1525 * XXX Make usb_sync_reset asynchronous.
1528 static void ub_reset_enter(struct ub_dev *sc, int try)
1532 /* This happens often on multi-LUN devices. */
1535 sc->reset = try + 1;
1537 #if 0 /* Not needed because the disconnect waits for us. */
1538 unsigned long flags;
1539 spin_lock_irqsave(&ub_lock, flags);
1541 spin_unlock_irqrestore(&ub_lock, flags);
1544 #if 0 /* We let them stop themselves. */
1545 struct list_head *p;
1547 list_for_each(p, &sc->luns) {
1548 lun = list_entry(p, struct ub_lun, link);
1549 blk_stop_queue(lun->disk->queue);
1553 schedule_work(&sc->reset_work);
1556 static void ub_reset_task(void *arg)
1558 struct ub_dev *sc = arg;
1559 unsigned long flags;
1560 struct list_head *p;
1565 printk(KERN_WARNING "%s: Running reset unrequested\n",
1570 if (atomic_read(&sc->poison)) {
1571 printk(KERN_NOTICE "%s: Not resetting disconnected device\n",
1572 sc->name); /* P3 This floods. Remove soon. XXX */
1573 } else if ((sc->reset & 1) == 0) {
1575 msleep(700); /* usb-storage sleeps 6s (!) */
1576 ub_probe_clear_stall(sc, sc->recv_bulk_pipe);
1577 ub_probe_clear_stall(sc, sc->send_bulk_pipe);
1578 } else if (sc->dev->actconfig->desc.bNumInterfaces != 1) {
1579 printk(KERN_NOTICE "%s: Not resetting multi-interface device\n",
1580 sc->name); /* P3 This floods. Remove soon. XXX */
1582 if ((lkr = usb_lock_device_for_reset(sc->dev, sc->intf)) < 0) {
1584 "%s: usb_lock_device_for_reset failed (%d)\n",
1587 rc = usb_reset_device(sc->dev);
1589 printk(KERN_NOTICE "%s: "
1590 "usb_lock_device_for_reset failed (%d)\n",
1595 usb_unlock_device(sc->dev);
1600 * In theory, no commands can be running while reset is active,
1601 * so nobody can ask for another reset, and so we do not need any
1602 * queues of resets or anything. We do need a spinlock though,
1603 * to interact with block layer.
1605 spin_lock_irqsave(sc->lock, flags);
1607 tasklet_schedule(&sc->tasklet);
1608 list_for_each(p, &sc->luns) {
1609 lun = list_entry(p, struct ub_lun, link);
1610 blk_start_queue(lun->disk->queue);
1612 wake_up(&sc->reset_wait);
1613 spin_unlock_irqrestore(sc->lock, flags);
1617 * This is called from a process context.
1619 static void ub_revalidate(struct ub_dev *sc, struct ub_lun *lun)
1622 lun->readonly = 0; /* XXX Query this from the device */
1624 lun->capacity.nsec = 0;
1625 lun->capacity.bsize = 512;
1626 lun->capacity.bshift = 0;
1628 if (ub_sync_tur(sc, lun) != 0)
1629 return; /* Not ready */
1632 if (ub_sync_read_cap(sc, lun, &lun->capacity) != 0) {
1634 * The retry here means something is wrong, either with the
1635 * device, with the transport, or with our code.
1636 * We keep this because sd.c has retries for capacity.
1638 if (ub_sync_read_cap(sc, lun, &lun->capacity) != 0) {
1639 lun->capacity.nsec = 0;
1640 lun->capacity.bsize = 512;
1641 lun->capacity.bshift = 0;
1648 * This is mostly needed to keep refcounting, but also to support
1649 * media checks on removable media drives.
1651 static int ub_bd_open(struct inode *inode, struct file *filp)
1653 struct gendisk *disk = inode->i_bdev->bd_disk;
1656 unsigned long flags;
1659 if ((lun = disk->private_data) == NULL)
1663 spin_lock_irqsave(&ub_lock, flags);
1664 if (atomic_read(&sc->poison)) {
1665 spin_unlock_irqrestore(&ub_lock, flags);
1669 spin_unlock_irqrestore(&ub_lock, flags);
1671 if (lun->removable || lun->readonly)
1672 check_disk_change(inode->i_bdev);
1675 * The sd.c considers ->media_present and ->changed not equivalent,
1676 * under some pretty murky conditions (a failure of READ CAPACITY).
1677 * We may need it one day.
1679 if (lun->removable && lun->changed && !(filp->f_flags & O_NDELAY)) {
1684 if (lun->readonly && (filp->f_mode & FMODE_WRITE)) {
1698 static int ub_bd_release(struct inode *inode, struct file *filp)
1700 struct gendisk *disk = inode->i_bdev->bd_disk;
1701 struct ub_lun *lun = disk->private_data;
1702 struct ub_dev *sc = lun->udev;
1709 * The ioctl interface.
1711 static int ub_bd_ioctl(struct inode *inode, struct file *filp,
1712 unsigned int cmd, unsigned long arg)
1714 struct gendisk *disk = inode->i_bdev->bd_disk;
1715 void __user *usermem = (void __user *) arg;
1717 return scsi_cmd_ioctl(filp, disk, cmd, usermem);
1721 * This is called once a new disk was seen by the block layer or by ub_probe().
1722 * The main onjective here is to discover the features of the media such as
1723 * the capacity, read-only status, etc. USB storage generally does not
1724 * need to be spun up, but if we needed it, this would be the place.
1726 * This call can sleep.
1728 * The return code is not used.
1730 static int ub_bd_revalidate(struct gendisk *disk)
1732 struct ub_lun *lun = disk->private_data;
1734 ub_revalidate(lun->udev, lun);
1736 /* XXX Support sector size switching like in sr.c */
1737 blk_queue_hardsect_size(disk->queue, lun->capacity.bsize);
1738 set_capacity(disk, lun->capacity.nsec);
1739 // set_disk_ro(sdkp->disk, lun->readonly);
1745 * The check is called by the block layer to verify if the media
1746 * is still available. It is supposed to be harmless, lightweight and
1747 * non-intrusive in case the media was not changed.
1749 * This call can sleep.
1751 * The return code is bool!
1753 static int ub_bd_media_changed(struct gendisk *disk)
1755 struct ub_lun *lun = disk->private_data;
1757 if (!lun->removable)
1761 * We clean checks always after every command, so this is not
1762 * as dangerous as it looks. If the TEST_UNIT_READY fails here,
1763 * the device is actually not ready with operator or software
1764 * intervention required. One dangerous item might be a drive which
1765 * spins itself down, and come the time to write dirty pages, this
1766 * will fail, then block layer discards the data. Since we never
1767 * spin drives up, such devices simply cannot be used with ub anyway.
1769 if (ub_sync_tur(lun->udev, lun) != 0) {
1774 return lun->changed;
1777 static struct block_device_operations ub_bd_fops = {
1778 .owner = THIS_MODULE,
1780 .release = ub_bd_release,
1781 .ioctl = ub_bd_ioctl,
1782 .media_changed = ub_bd_media_changed,
1783 .revalidate_disk = ub_bd_revalidate,
1787 * Common ->done routine for commands executed synchronously.
1789 static void ub_probe_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1791 struct completion *cop = cmd->back;
1796 * Test if the device has a check condition on it, synchronously.
1798 static int ub_sync_tur(struct ub_dev *sc, struct ub_lun *lun)
1800 struct ub_scsi_cmd *cmd;
1801 enum { ALLOC_SIZE = sizeof(struct ub_scsi_cmd) };
1802 unsigned long flags;
1803 struct completion compl;
1806 init_completion(&compl);
1809 if ((cmd = kzalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
1812 cmd->cdb[0] = TEST_UNIT_READY;
1814 cmd->dir = UB_DIR_NONE;
1815 cmd->state = UB_CMDST_INIT;
1816 cmd->lun = lun; /* This may be NULL, but that's ok */
1817 cmd->done = ub_probe_done;
1820 spin_lock_irqsave(sc->lock, flags);
1821 cmd->tag = sc->tagcnt++;
1823 rc = ub_submit_scsi(sc, cmd);
1824 spin_unlock_irqrestore(sc->lock, flags);
1827 printk("ub: testing ready: submit error (%d)\n", rc); /* P3 */
1831 wait_for_completion(&compl);
1835 if (rc == -EIO && cmd->key != 0) /* Retries for benh's key */
1845 * Read the SCSI capacity synchronously (for probing).
1847 static int ub_sync_read_cap(struct ub_dev *sc, struct ub_lun *lun,
1848 struct ub_capacity *ret)
1850 struct ub_scsi_cmd *cmd;
1851 struct scatterlist *sg;
1853 enum { ALLOC_SIZE = sizeof(struct ub_scsi_cmd) + 8 };
1854 unsigned long flags;
1855 unsigned int bsize, shift;
1857 struct completion compl;
1860 init_completion(&compl);
1863 if ((cmd = kzalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
1865 p = (char *)cmd + sizeof(struct ub_scsi_cmd);
1869 cmd->dir = UB_DIR_READ;
1870 cmd->state = UB_CMDST_INIT;
1873 sg->page = virt_to_page(p);
1874 sg->offset = (unsigned long)p & (PAGE_SIZE-1);
1878 cmd->done = ub_probe_done;
1881 spin_lock_irqsave(sc->lock, flags);
1882 cmd->tag = sc->tagcnt++;
1884 rc = ub_submit_scsi(sc, cmd);
1885 spin_unlock_irqrestore(sc->lock, flags);
1888 printk("ub: reading capacity: submit error (%d)\n", rc); /* P3 */
1892 wait_for_completion(&compl);
1894 if (cmd->error != 0) {
1895 printk("ub: reading capacity: error %d\n", cmd->error); /* P3 */
1899 if (cmd->act_len != 8) {
1900 printk("ub: reading capacity: size %d\n", cmd->act_len); /* P3 */
1905 /* sd.c special-cases sector size of 0 to mean 512. Needed? Safe? */
1906 nsec = be32_to_cpu(*(__be32 *)p) + 1;
1907 bsize = be32_to_cpu(*(__be32 *)(p + 4));
1909 case 512: shift = 0; break;
1910 case 1024: shift = 1; break;
1911 case 2048: shift = 2; break;
1912 case 4096: shift = 3; break;
1914 printk("ub: Bad sector size %u\n", bsize); /* P3 */
1920 ret->bshift = shift;
1921 ret->nsec = nsec << shift;
1934 static void ub_probe_urb_complete(struct urb *urb, struct pt_regs *pt)
1936 struct completion *cop = urb->context;
1940 static void ub_probe_timeout(unsigned long arg)
1942 struct completion *cop = (struct completion *) arg;
1947 * Reset with a Bulk reset.
1949 static int ub_sync_reset(struct ub_dev *sc)
1951 int ifnum = sc->intf->cur_altsetting->desc.bInterfaceNumber;
1952 struct usb_ctrlrequest *cr;
1953 struct completion compl;
1954 struct timer_list timer;
1957 init_completion(&compl);
1960 cr->bRequestType = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
1961 cr->bRequest = US_BULK_RESET_REQUEST;
1962 cr->wValue = cpu_to_le16(0);
1963 cr->wIndex = cpu_to_le16(ifnum);
1964 cr->wLength = cpu_to_le16(0);
1966 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
1967 (unsigned char*) cr, NULL, 0, ub_probe_urb_complete, &compl);
1968 sc->work_urb.actual_length = 0;
1969 sc->work_urb.error_count = 0;
1970 sc->work_urb.status = 0;
1972 if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0) {
1974 "%s: Unable to submit a bulk reset (%d)\n", sc->name, rc);
1979 timer.function = ub_probe_timeout;
1980 timer.data = (unsigned long) &compl;
1981 timer.expires = jiffies + UB_CTRL_TIMEOUT;
1984 wait_for_completion(&compl);
1986 del_timer_sync(&timer);
1987 usb_kill_urb(&sc->work_urb);
1989 return sc->work_urb.status;
1993 * Get number of LUNs by the way of Bulk GetMaxLUN command.
1995 static int ub_sync_getmaxlun(struct ub_dev *sc)
1997 int ifnum = sc->intf->cur_altsetting->desc.bInterfaceNumber;
1999 enum { ALLOC_SIZE = 1 };
2000 struct usb_ctrlrequest *cr;
2001 struct completion compl;
2002 struct timer_list timer;
2006 init_completion(&compl);
2009 if ((p = kmalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
2014 cr->bRequestType = USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE;
2015 cr->bRequest = US_BULK_GET_MAX_LUN;
2016 cr->wValue = cpu_to_le16(0);
2017 cr->wIndex = cpu_to_le16(ifnum);
2018 cr->wLength = cpu_to_le16(1);
2020 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->recv_ctrl_pipe,
2021 (unsigned char*) cr, p, 1, ub_probe_urb_complete, &compl);
2022 sc->work_urb.actual_length = 0;
2023 sc->work_urb.error_count = 0;
2024 sc->work_urb.status = 0;
2026 if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0) {
2028 printk("%s: Stall submitting GetMaxLUN, using 1 LUN\n",
2032 "%s: Unable to submit GetMaxLUN (%d)\n",
2039 timer.function = ub_probe_timeout;
2040 timer.data = (unsigned long) &compl;
2041 timer.expires = jiffies + UB_CTRL_TIMEOUT;
2044 wait_for_completion(&compl);
2046 del_timer_sync(&timer);
2047 usb_kill_urb(&sc->work_urb);
2049 if ((rc = sc->work_urb.status) < 0) {
2051 printk("%s: Stall at GetMaxLUN, using 1 LUN\n",
2055 "%s: Error at GetMaxLUN (%d)\n",
2061 if (sc->work_urb.actual_length != 1) {
2062 printk("%s: GetMaxLUN returned %d bytes\n", sc->name,
2063 sc->work_urb.actual_length); /* P3 */
2066 if ((nluns = *p) == 55) {
2069 /* GetMaxLUN returns the maximum LUN number */
2071 if (nluns > UB_MAX_LUNS)
2072 nluns = UB_MAX_LUNS;
2074 printk("%s: GetMaxLUN returned %d, using %d LUNs\n", sc->name,
2075 *p, nluns); /* P3 */
2089 * Clear initial stalls.
2091 static int ub_probe_clear_stall(struct ub_dev *sc, int stalled_pipe)
2094 struct usb_ctrlrequest *cr;
2095 struct completion compl;
2096 struct timer_list timer;
2099 init_completion(&compl);
2101 endp = usb_pipeendpoint(stalled_pipe);
2102 if (usb_pipein (stalled_pipe))
2106 cr->bRequestType = USB_RECIP_ENDPOINT;
2107 cr->bRequest = USB_REQ_CLEAR_FEATURE;
2108 cr->wValue = cpu_to_le16(USB_ENDPOINT_HALT);
2109 cr->wIndex = cpu_to_le16(endp);
2110 cr->wLength = cpu_to_le16(0);
2112 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
2113 (unsigned char*) cr, NULL, 0, ub_probe_urb_complete, &compl);
2114 sc->work_urb.actual_length = 0;
2115 sc->work_urb.error_count = 0;
2116 sc->work_urb.status = 0;
2118 if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0) {
2120 "%s: Unable to submit a probe clear (%d)\n", sc->name, rc);
2125 timer.function = ub_probe_timeout;
2126 timer.data = (unsigned long) &compl;
2127 timer.expires = jiffies + UB_CTRL_TIMEOUT;
2130 wait_for_completion(&compl);
2132 del_timer_sync(&timer);
2133 usb_kill_urb(&sc->work_urb);
2135 /* reset the endpoint toggle */
2136 usb_settoggle(sc->dev, endp, usb_pipeout(sc->last_pipe), 0);
2142 * Get the pipe settings.
2144 static int ub_get_pipes(struct ub_dev *sc, struct usb_device *dev,
2145 struct usb_interface *intf)
2147 struct usb_host_interface *altsetting = intf->cur_altsetting;
2148 struct usb_endpoint_descriptor *ep_in = NULL;
2149 struct usb_endpoint_descriptor *ep_out = NULL;
2150 struct usb_endpoint_descriptor *ep;
2154 * Find the endpoints we need.
2155 * We are expecting a minimum of 2 endpoints - in and out (bulk).
2156 * We will ignore any others.
2158 for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
2159 ep = &altsetting->endpoint[i].desc;
2161 /* Is it a BULK endpoint? */
2162 if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
2163 == USB_ENDPOINT_XFER_BULK) {
2164 /* BULK in or out? */
2165 if (ep->bEndpointAddress & USB_DIR_IN)
2172 if (ep_in == NULL || ep_out == NULL) {
2173 printk(KERN_NOTICE "%s: failed endpoint check\n",
2178 /* Calculate and store the pipe values */
2179 sc->send_ctrl_pipe = usb_sndctrlpipe(dev, 0);
2180 sc->recv_ctrl_pipe = usb_rcvctrlpipe(dev, 0);
2181 sc->send_bulk_pipe = usb_sndbulkpipe(dev,
2182 ep_out->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2183 sc->recv_bulk_pipe = usb_rcvbulkpipe(dev,
2184 ep_in->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2190 * Probing is done in the process context, which allows us to cheat
2191 * and not to build a state machine for the discovery.
2193 static int ub_probe(struct usb_interface *intf,
2194 const struct usb_device_id *dev_id)
2201 if (usb_usual_check_type(dev_id, USB_US_TYPE_UB))
2205 if ((sc = kzalloc(sizeof(struct ub_dev), GFP_KERNEL)) == NULL)
2207 sc->lock = ub_next_lock();
2208 INIT_LIST_HEAD(&sc->luns);
2209 usb_init_urb(&sc->work_urb);
2210 tasklet_init(&sc->tasklet, ub_scsi_action, (unsigned long)sc);
2211 atomic_set(&sc->poison, 0);
2212 INIT_WORK(&sc->reset_work, ub_reset_task, sc);
2213 init_waitqueue_head(&sc->reset_wait);
2215 init_timer(&sc->work_timer);
2216 sc->work_timer.data = (unsigned long) sc;
2217 sc->work_timer.function = ub_urb_timeout;
2219 ub_init_completion(&sc->work_done);
2220 sc->work_done.done = 1; /* A little yuk, but oh well... */
2222 sc->dev = interface_to_usbdev(intf);
2224 // sc->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
2225 usb_set_intfdata(intf, sc);
2226 usb_get_dev(sc->dev);
2228 * Since we give the interface struct to the block level through
2229 * disk->driverfs_dev, we have to pin it. Otherwise, block_uevent
2230 * oopses on close after a disconnect (kernels 2.6.16 and up).
2232 usb_get_intf(sc->intf);
2234 snprintf(sc->name, 12, DRV_NAME "(%d.%d)",
2235 sc->dev->bus->busnum, sc->dev->devnum);
2237 /* XXX Verify that we can handle the device (from descriptors) */
2239 if (ub_get_pipes(sc, sc->dev, intf) != 0)
2243 * At this point, all USB initialization is done, do upper layer.
2244 * We really hate halfway initialized structures, so from the
2245 * invariants perspective, this ub_dev is fully constructed at
2250 * This is needed to clear toggles. It is a problem only if we do
2251 * `rmmod ub && modprobe ub` without disconnects, but we like that.
2253 #if 0 /* iPod Mini fails if we do this (big white iPod works) */
2254 ub_probe_clear_stall(sc, sc->recv_bulk_pipe);
2255 ub_probe_clear_stall(sc, sc->send_bulk_pipe);
2259 * The way this is used by the startup code is a little specific.
2260 * A SCSI check causes a USB stall. Our common case code sees it
2261 * and clears the check, after which the device is ready for use.
2262 * But if a check was not present, any command other than
2263 * TEST_UNIT_READY ends with a lockup (including REQUEST_SENSE).
2265 * If we neglect to clear the SCSI check, the first real command fails
2266 * (which is the capacity readout). We clear that and retry, but why
2267 * causing spurious retries for no reason.
2269 * Revalidation may start with its own TEST_UNIT_READY, but that one
2270 * has to succeed, so we clear checks with an additional one here.
2271 * In any case it's not our business how revaliadation is implemented.
2273 for (i = 0; i < 3; i++) { /* Retries for benh's key */
2274 if ((rc = ub_sync_tur(sc, NULL)) <= 0) break;
2275 if (rc != 0x6) break;
2280 for (i = 0; i < 3; i++) {
2281 if ((rc = ub_sync_getmaxlun(sc)) < 0)
2290 for (i = 0; i < nluns; i++) {
2291 ub_probe_lun(sc, i);
2296 usb_set_intfdata(intf, NULL);
2297 usb_put_intf(sc->intf);
2298 usb_put_dev(sc->dev);
2304 static int ub_probe_lun(struct ub_dev *sc, int lnum)
2308 struct gendisk *disk;
2312 if ((lun = kzalloc(sizeof(struct ub_lun), GFP_KERNEL)) == NULL)
2317 if ((lun->id = ub_id_get()) == -1)
2321 list_add(&lun->link, &sc->luns);
2323 snprintf(lun->name, 16, DRV_NAME "%c(%d.%d.%d)",
2324 lun->id + 'a', sc->dev->bus->busnum, sc->dev->devnum, lun->num);
2326 lun->removable = 1; /* XXX Query this from the device */
2327 lun->changed = 1; /* ub_revalidate clears only */
2328 ub_revalidate(sc, lun);
2331 if ((disk = alloc_disk(UB_PARTS_PER_LUN)) == NULL)
2335 sprintf(disk->disk_name, DRV_NAME "%c", lun->id + 'a');
2336 sprintf(disk->devfs_name, DEVFS_NAME "/%c", lun->id + 'a');
2337 disk->major = UB_MAJOR;
2338 disk->first_minor = lun->id * UB_PARTS_PER_LUN;
2339 disk->fops = &ub_bd_fops;
2340 disk->private_data = lun;
2341 disk->driverfs_dev = &sc->intf->dev;
2344 if ((q = blk_init_queue(ub_request_fn, sc->lock)) == NULL)
2349 blk_queue_bounce_limit(q, BLK_BOUNCE_HIGH);
2350 blk_queue_max_hw_segments(q, UB_MAX_REQ_SG);
2351 blk_queue_max_phys_segments(q, UB_MAX_REQ_SG);
2352 blk_queue_segment_boundary(q, 0xffffffff); /* Dubious. */
2353 blk_queue_max_sectors(q, UB_MAX_SECTORS);
2354 blk_queue_hardsect_size(q, lun->capacity.bsize);
2358 set_capacity(disk, lun->capacity.nsec);
2360 disk->flags |= GENHD_FL_REMOVABLE;
2369 list_del(&lun->link);
2377 static void ub_disconnect(struct usb_interface *intf)
2379 struct ub_dev *sc = usb_get_intfdata(intf);
2380 struct list_head *p;
2382 struct gendisk *disk;
2383 unsigned long flags;
2386 * Prevent ub_bd_release from pulling the rug from under us.
2387 * XXX This is starting to look like a kref.
2388 * XXX Why not to take this ref at probe time?
2390 spin_lock_irqsave(&ub_lock, flags);
2392 spin_unlock_irqrestore(&ub_lock, flags);
2395 * Fence stall clearnings, operations triggered by unlinkings and so on.
2396 * We do not attempt to unlink any URBs, because we do not trust the
2397 * unlink paths in HC drivers. Also, we get -84 upon disconnect anyway.
2399 atomic_set(&sc->poison, 1);
2402 * Wait for reset to end, if any.
2404 wait_event(sc->reset_wait, !sc->reset);
2407 * Blow away queued commands.
2409 * Actually, this never works, because before we get here
2410 * the HCD terminates outstanding URB(s). It causes our
2411 * SCSI command queue to advance, commands fail to submit,
2412 * and the whole queue drains. So, we just use this code to
2415 spin_lock_irqsave(sc->lock, flags);
2417 struct ub_scsi_cmd *cmd;
2419 while ((cmd = ub_cmdq_peek(sc)) != NULL) {
2420 cmd->error = -ENOTCONN;
2421 cmd->state = UB_CMDST_DONE;
2423 (*cmd->done)(sc, cmd);
2427 printk(KERN_WARNING "%s: "
2428 "%d was queued after shutdown\n", sc->name, cnt);
2431 spin_unlock_irqrestore(sc->lock, flags);
2434 * Unregister the upper layer.
2436 list_for_each (p, &sc->luns) {
2437 lun = list_entry(p, struct ub_lun, link);
2439 if (disk->flags & GENHD_FL_UP)
2442 * I wish I could do:
2443 * set_bit(QUEUE_FLAG_DEAD, &q->queue_flags);
2444 * As it is, we rely on our internal poisoning and let
2445 * the upper levels to spin furiously failing all the I/O.
2450 * Testing for -EINPROGRESS is always a bug, so we are bending
2451 * the rules a little.
2453 spin_lock_irqsave(sc->lock, flags);
2454 if (sc->work_urb.status == -EINPROGRESS) { /* janitors: ignore */
2455 printk(KERN_WARNING "%s: "
2456 "URB is active after disconnect\n", sc->name);
2458 spin_unlock_irqrestore(sc->lock, flags);
2461 * There is virtually no chance that other CPU runs times so long
2462 * after ub_urb_complete should have called del_timer, but only if HCD
2463 * didn't forget to deliver a callback on unlink.
2465 del_timer_sync(&sc->work_timer);
2468 * At this point there must be no commands coming from anyone
2469 * and no URBs left in transit.
2475 static struct usb_driver ub_driver = {
2478 .disconnect = ub_disconnect,
2479 .id_table = ub_usb_ids,
2482 static int __init ub_init(void)
2487 for (i = 0; i < UB_QLOCK_NUM; i++)
2488 spin_lock_init(&ub_qlockv[i]);
2490 if ((rc = register_blkdev(UB_MAJOR, DRV_NAME)) != 0)
2492 devfs_mk_dir(DEVFS_NAME);
2494 if ((rc = usb_register(&ub_driver)) != 0)
2497 usb_usual_set_present(USB_US_TYPE_UB);
2501 devfs_remove(DEVFS_NAME);
2502 unregister_blkdev(UB_MAJOR, DRV_NAME);
2507 static void __exit ub_exit(void)
2509 usb_deregister(&ub_driver);
2511 devfs_remove(DEVFS_NAME);
2512 unregister_blkdev(UB_MAJOR, DRV_NAME);
2513 usb_usual_clear_present(USB_US_TYPE_UB);
2516 module_init(ub_init);
2517 module_exit(ub_exit);
2519 MODULE_LICENSE("GPL");