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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/block/ub.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/block/ub.c')
-rw-r--r--drivers/block/ub.c2215
1 files changed, 2215 insertions, 0 deletions
diff --git a/drivers/block/ub.c b/drivers/block/ub.c
new file mode 100644
index 00000000000..ce42889f98f
--- /dev/null
+++ b/drivers/block/ub.c
@@ -0,0 +1,2215 @@
+/*
+ * The low performance USB storage driver (ub).
+ *
+ * Copyright (c) 1999, 2000 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
+ * Copyright (C) 2004 Pete Zaitcev (zaitcev@yahoo.com)
+ *
+ * This work is a part of Linux kernel, is derived from it,
+ * and is not licensed separately. See file COPYING for details.
+ *
+ * TODO (sorted by decreasing priority)
+ * -- Do resets with usb_device_reset (needs a thread context, use khubd)
+ * -- set readonly flag for CDs, set removable flag for CF readers
+ * -- do inquiry and verify we got a disk and not a tape (for LUN mismatch)
+ * -- support pphaneuf's SDDR-75 with two LUNs (also broken capacity...)
+ * -- special case some senses, e.g. 3a/0 -> no media present, reduce retries
+ * -- verify the 13 conditions and do bulk resets
+ * -- normal pool of commands instead of cmdv[]?
+ * -- kill last_pipe and simply do two-state clearing on both pipes
+ * -- verify protocol (bulk) from USB descriptors (maybe...)
+ * -- highmem and sg
+ * -- move top_sense and work_bcs into separate allocations (if they survive)
+ * for cache purists and esoteric architectures.
+ * -- prune comments, they are too volumnous
+ * -- Exterminate P3 printks
+ * -- Resove XXX's
+ * -- Redo "benh's retries", perhaps have spin-up code to handle them. V:D=?
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/blkdev.h>
+#include <linux/devfs_fs_kernel.h>
+#include <linux/timer.h>
+#include <scsi/scsi.h>
+
+#define DRV_NAME "ub"
+#define DEVFS_NAME DRV_NAME
+
+#define UB_MAJOR 180
+
+/*
+ * Definitions which have to be scattered once we understand the layout better.
+ */
+
+/* Transport (despite PR in the name) */
+#define US_PR_BULK 0x50 /* bulk only */
+
+/* Protocol */
+#define US_SC_SCSI 0x06 /* Transparent */
+
+/*
+ */
+#define UB_MINORS_PER_MAJOR 8
+
+#define UB_MAX_CDB_SIZE 16 /* Corresponds to Bulk */
+
+#define UB_SENSE_SIZE 18
+
+/*
+ */
+
+/* command block wrapper */
+struct bulk_cb_wrap {
+ __le32 Signature; /* contains 'USBC' */
+ u32 Tag; /* unique per command id */
+ __le32 DataTransferLength; /* size of data */
+ u8 Flags; /* direction in bit 0 */
+ u8 Lun; /* LUN normally 0 */
+ u8 Length; /* of of the CDB */
+ u8 CDB[UB_MAX_CDB_SIZE]; /* max command */
+};
+
+#define US_BULK_CB_WRAP_LEN 31
+#define US_BULK_CB_SIGN 0x43425355 /*spells out USBC */
+#define US_BULK_FLAG_IN 1
+#define US_BULK_FLAG_OUT 0
+
+/* command status wrapper */
+struct bulk_cs_wrap {
+ __le32 Signature; /* should = 'USBS' */
+ u32 Tag; /* same as original command */
+ __le32 Residue; /* amount not transferred */
+ u8 Status; /* see below */
+};
+
+#define US_BULK_CS_WRAP_LEN 13
+#define US_BULK_CS_SIGN 0x53425355 /* spells out 'USBS' */
+/* This is for Olympus Camedia digital cameras */
+#define US_BULK_CS_OLYMPUS_SIGN 0x55425355 /* spells out 'USBU' */
+#define US_BULK_STAT_OK 0
+#define US_BULK_STAT_FAIL 1
+#define US_BULK_STAT_PHASE 2
+
+/* bulk-only class specific requests */
+#define US_BULK_RESET_REQUEST 0xff
+#define US_BULK_GET_MAX_LUN 0xfe
+
+/*
+ */
+struct ub_dev;
+
+#define UB_MAX_REQ_SG 1
+#define UB_MAX_SECTORS 64
+
+/*
+ * A second is more than enough for a 32K transfer (UB_MAX_SECTORS)
+ * even if a webcam hogs the bus, but some devices need time to spin up.
+ */
+#define UB_URB_TIMEOUT (HZ*2)
+#define UB_DATA_TIMEOUT (HZ*5) /* ZIP does spin-ups in the data phase */
+#define UB_STAT_TIMEOUT (HZ*5) /* Same spinups and eject for a dataless cmd. */
+#define UB_CTRL_TIMEOUT (HZ/2) /* 500ms ought to be enough to clear a stall */
+
+/*
+ * An instance of a SCSI command in transit.
+ */
+#define UB_DIR_NONE 0
+#define UB_DIR_READ 1
+#define UB_DIR_ILLEGAL2 2
+#define UB_DIR_WRITE 3
+
+#define UB_DIR_CHAR(c) (((c)==UB_DIR_WRITE)? 'w': \
+ (((c)==UB_DIR_READ)? 'r': 'n'))
+
+enum ub_scsi_cmd_state {
+ UB_CMDST_INIT, /* Initial state */
+ UB_CMDST_CMD, /* Command submitted */
+ UB_CMDST_DATA, /* Data phase */
+ UB_CMDST_CLR2STS, /* Clearing before requesting status */
+ UB_CMDST_STAT, /* Status phase */
+ UB_CMDST_CLEAR, /* Clearing a stall (halt, actually) */
+ UB_CMDST_SENSE, /* Sending Request Sense */
+ UB_CMDST_DONE /* Final state */
+};
+
+static char *ub_scsi_cmd_stname[] = {
+ ". ",
+ "Cmd",
+ "dat",
+ "c2s",
+ "sts",
+ "clr",
+ "Sen",
+ "fin"
+};
+
+struct ub_scsi_cmd {
+ unsigned char cdb[UB_MAX_CDB_SIZE];
+ unsigned char cdb_len;
+
+ unsigned char dir; /* 0 - none, 1 - read, 3 - write. */
+ unsigned char trace_index;
+ enum ub_scsi_cmd_state state;
+ unsigned int tag;
+ struct ub_scsi_cmd *next;
+
+ int error; /* Return code - valid upon done */
+ unsigned int act_len; /* Return size */
+ unsigned char key, asc, ascq; /* May be valid if error==-EIO */
+
+ int stat_count; /* Retries getting status. */
+
+ /*
+ * We do not support transfers from highmem pages
+ * because the underlying USB framework does not do what we need.
+ */
+ char *data; /* Requested buffer */
+ unsigned int len; /* Requested length */
+ // struct scatterlist sgv[UB_MAX_REQ_SG];
+
+ void (*done)(struct ub_dev *, struct ub_scsi_cmd *);
+ void *back;
+};
+
+/*
+ */
+struct ub_capacity {
+ unsigned long nsec; /* Linux size - 512 byte sectors */
+ unsigned int bsize; /* Linux hardsect_size */
+ unsigned int bshift; /* Shift between 512 and hard sects */
+};
+
+/*
+ * The SCSI command tracing structure.
+ */
+
+#define SCMD_ST_HIST_SZ 8
+#define SCMD_TRACE_SZ 63 /* Less than 4KB of 61-byte lines */
+
+struct ub_scsi_cmd_trace {
+ int hcur;
+ unsigned int tag;
+ unsigned int req_size, act_size;
+ unsigned char op;
+ unsigned char dir;
+ unsigned char key, asc, ascq;
+ char st_hst[SCMD_ST_HIST_SZ];
+};
+
+struct ub_scsi_trace {
+ int cur;
+ struct ub_scsi_cmd_trace vec[SCMD_TRACE_SZ];
+};
+
+/*
+ * This is a direct take-off from linux/include/completion.h
+ * The difference is that I do not wait on this thing, just poll.
+ * When I want to wait (ub_probe), I just use the stock completion.
+ *
+ * Note that INIT_COMPLETION takes no lock. It is correct. But why
+ * in the bloody hell that thing takes struct instead of pointer to struct
+ * is quite beyond me. I just copied it from the stock completion.
+ */
+struct ub_completion {
+ unsigned int done;
+ spinlock_t lock;
+};
+
+static inline void ub_init_completion(struct ub_completion *x)
+{
+ x->done = 0;
+ spin_lock_init(&x->lock);
+}
+
+#define UB_INIT_COMPLETION(x) ((x).done = 0)
+
+static void ub_complete(struct ub_completion *x)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&x->lock, flags);
+ x->done++;
+ spin_unlock_irqrestore(&x->lock, flags);
+}
+
+static int ub_is_completed(struct ub_completion *x)
+{
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&x->lock, flags);
+ ret = x->done;
+ spin_unlock_irqrestore(&x->lock, flags);
+ return ret;
+}
+
+/*
+ */
+struct ub_scsi_cmd_queue {
+ int qlen, qmax;
+ struct ub_scsi_cmd *head, *tail;
+};
+
+/*
+ * The UB device instance.
+ */
+struct ub_dev {
+ spinlock_t lock;
+ int id; /* Number among ub's */
+ atomic_t poison; /* The USB device is disconnected */
+ int openc; /* protected by ub_lock! */
+ /* kref is too implicit for our taste */
+ unsigned int tagcnt;
+ int changed; /* Media was changed */
+ int removable;
+ int readonly;
+ int first_open; /* Kludge. See ub_bd_open. */
+ char name[8];
+ struct usb_device *dev;
+ struct usb_interface *intf;
+
+ struct ub_capacity capacity;
+ struct gendisk *disk;
+
+ unsigned int send_bulk_pipe; /* cached pipe values */
+ unsigned int recv_bulk_pipe;
+ unsigned int send_ctrl_pipe;
+ unsigned int recv_ctrl_pipe;
+
+ struct tasklet_struct tasklet;
+
+ /* XXX Use Ingo's mempool (once we have more than one) */
+ int cmda[1];
+ struct ub_scsi_cmd cmdv[1];
+
+ struct ub_scsi_cmd_queue cmd_queue;
+ struct ub_scsi_cmd top_rqs_cmd; /* REQUEST SENSE */
+ unsigned char top_sense[UB_SENSE_SIZE];
+
+ struct ub_completion work_done;
+ struct urb work_urb;
+ struct timer_list work_timer;
+ int last_pipe; /* What might need clearing */
+ struct bulk_cb_wrap work_bcb;
+ struct bulk_cs_wrap work_bcs;
+ struct usb_ctrlrequest work_cr;
+
+ struct ub_scsi_trace tr;
+};
+
+/*
+ */
+static void ub_cleanup(struct ub_dev *sc);
+static int ub_bd_rq_fn_1(struct ub_dev *sc, struct request *rq);
+static int ub_cmd_build_block(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
+ struct request *rq);
+static int ub_cmd_build_packet(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
+ struct request *rq);
+static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
+static void ub_end_rq(struct request *rq, int uptodate);
+static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
+static void ub_urb_complete(struct urb *urb, struct pt_regs *pt);
+static void ub_scsi_action(unsigned long _dev);
+static void ub_scsi_dispatch(struct ub_dev *sc);
+static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
+static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc);
+static void __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
+static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
+static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
+static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
+ int stalled_pipe);
+static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd);
+static int ub_sync_tur(struct ub_dev *sc);
+static int ub_sync_read_cap(struct ub_dev *sc, struct ub_capacity *ret);
+
+/*
+ */
+static struct usb_device_id ub_usb_ids[] = {
+ // { USB_DEVICE_VER(0x0781, 0x0002, 0x0009, 0x0009) }, /* SDDR-31 */
+ { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_SCSI, US_PR_BULK) },
+ { }
+};
+
+MODULE_DEVICE_TABLE(usb, ub_usb_ids);
+
+/*
+ * Find me a way to identify "next free minor" for add_disk(),
+ * and the array disappears the next day. However, the number of
+ * hosts has something to do with the naming and /proc/partitions.
+ * This has to be thought out in detail before changing.
+ * If UB_MAX_HOST was 1000, we'd use a bitmap. Or a better data structure.
+ */
+#define UB_MAX_HOSTS 26
+static char ub_hostv[UB_MAX_HOSTS];
+static DEFINE_SPINLOCK(ub_lock); /* Locks globals and ->openc */
+
+/*
+ * The SCSI command tracing procedures.
+ */
+
+static void ub_cmdtr_new(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ int n;
+ struct ub_scsi_cmd_trace *t;
+
+ if ((n = sc->tr.cur + 1) == SCMD_TRACE_SZ) n = 0;
+ t = &sc->tr.vec[n];
+
+ memset(t, 0, sizeof(struct ub_scsi_cmd_trace));
+ t->tag = cmd->tag;
+ t->op = cmd->cdb[0];
+ t->dir = cmd->dir;
+ t->req_size = cmd->len;
+ t->st_hst[0] = cmd->state;
+
+ sc->tr.cur = n;
+ cmd->trace_index = n;
+}
+
+static void ub_cmdtr_state(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ int n;
+ struct ub_scsi_cmd_trace *t;
+
+ t = &sc->tr.vec[cmd->trace_index];
+ if (t->tag == cmd->tag) {
+ if ((n = t->hcur + 1) == SCMD_ST_HIST_SZ) n = 0;
+ t->st_hst[n] = cmd->state;
+ t->hcur = n;
+ }
+}
+
+static void ub_cmdtr_act_len(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ struct ub_scsi_cmd_trace *t;
+
+ t = &sc->tr.vec[cmd->trace_index];
+ if (t->tag == cmd->tag)
+ t->act_size = cmd->act_len;
+}
+
+static void ub_cmdtr_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
+ unsigned char *sense)
+{
+ struct ub_scsi_cmd_trace *t;
+
+ t = &sc->tr.vec[cmd->trace_index];
+ if (t->tag == cmd->tag) {
+ t->key = sense[2] & 0x0F;
+ t->asc = sense[12];
+ t->ascq = sense[13];
+ }
+}
+
+static ssize_t ub_diag_show(struct device *dev, char *page)
+{
+ struct usb_interface *intf;
+ struct ub_dev *sc;
+ int cnt;
+ unsigned long flags;
+ int nc, nh;
+ int i, j;
+ struct ub_scsi_cmd_trace *t;
+
+ intf = to_usb_interface(dev);
+ sc = usb_get_intfdata(intf);
+ if (sc == NULL)
+ return 0;
+
+ cnt = 0;
+ spin_lock_irqsave(&sc->lock, flags);
+
+ cnt += sprintf(page + cnt,
+ "qlen %d qmax %d changed %d removable %d readonly %d\n",
+ sc->cmd_queue.qlen, sc->cmd_queue.qmax,
+ sc->changed, sc->removable, sc->readonly);
+
+ if ((nc = sc->tr.cur + 1) == SCMD_TRACE_SZ) nc = 0;
+ for (j = 0; j < SCMD_TRACE_SZ; j++) {
+ t = &sc->tr.vec[nc];
+
+ cnt += sprintf(page + cnt, "%08x %02x", t->tag, t->op);
+ if (t->op == REQUEST_SENSE) {
+ cnt += sprintf(page + cnt, " [sense %x %02x %02x]",
+ t->key, t->asc, t->ascq);
+ } else {
+ cnt += sprintf(page + cnt, " %c", UB_DIR_CHAR(t->dir));
+ cnt += sprintf(page + cnt, " [%5d %5d]",
+ t->req_size, t->act_size);
+ }
+ if ((nh = t->hcur + 1) == SCMD_ST_HIST_SZ) nh = 0;
+ for (i = 0; i < SCMD_ST_HIST_SZ; i++) {
+ cnt += sprintf(page + cnt, " %s",
+ ub_scsi_cmd_stname[(int)t->st_hst[nh]]);
+ if (++nh == SCMD_ST_HIST_SZ) nh = 0;
+ }
+ cnt += sprintf(page + cnt, "\n");
+
+ if (++nc == SCMD_TRACE_SZ) nc = 0;
+ }
+
+ spin_unlock_irqrestore(&sc->lock, flags);
+ return cnt;
+}
+
+static DEVICE_ATTR(diag, S_IRUGO, ub_diag_show, NULL); /* N.B. World readable */
+
+/*
+ * The id allocator.
+ *
+ * This also stores the host for indexing by minor, which is somewhat dirty.
+ */
+static int ub_id_get(void)
+{
+ unsigned long flags;
+ int i;
+
+ spin_lock_irqsave(&ub_lock, flags);
+ for (i = 0; i < UB_MAX_HOSTS; i++) {
+ if (ub_hostv[i] == 0) {
+ ub_hostv[i] = 1;
+ spin_unlock_irqrestore(&ub_lock, flags);
+ return i;
+ }
+ }
+ spin_unlock_irqrestore(&ub_lock, flags);
+ return -1;
+}
+
+static void ub_id_put(int id)
+{
+ unsigned long flags;
+
+ if (id < 0 || id >= UB_MAX_HOSTS) {
+ printk(KERN_ERR DRV_NAME ": bad host ID %d\n", id);
+ return;
+ }
+
+ spin_lock_irqsave(&ub_lock, flags);
+ if (ub_hostv[id] == 0) {
+ spin_unlock_irqrestore(&ub_lock, flags);
+ printk(KERN_ERR DRV_NAME ": freeing free host ID %d\n", id);
+ return;
+ }
+ ub_hostv[id] = 0;
+ spin_unlock_irqrestore(&ub_lock, flags);
+}
+
+/*
+ * Downcount for deallocation. This rides on two assumptions:
+ * - once something is poisoned, its refcount cannot grow
+ * - opens cannot happen at this time (del_gendisk was done)
+ * If the above is true, we can drop the lock, which we need for
+ * blk_cleanup_queue(): the silly thing may attempt to sleep.
+ * [Actually, it never needs to sleep for us, but it calls might_sleep()]
+ */
+static void ub_put(struct ub_dev *sc)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&ub_lock, flags);
+ --sc->openc;
+ if (sc->openc == 0 && atomic_read(&sc->poison)) {
+ spin_unlock_irqrestore(&ub_lock, flags);
+ ub_cleanup(sc);
+ } else {
+ spin_unlock_irqrestore(&ub_lock, flags);
+ }
+}
+
+/*
+ * Final cleanup and deallocation.
+ */
+static void ub_cleanup(struct ub_dev *sc)
+{
+ request_queue_t *q;
+
+ /* I don't think queue can be NULL. But... Stolen from sx8.c */
+ if ((q = sc->disk->queue) != NULL)
+ blk_cleanup_queue(q);
+
+ /*
+ * If we zero disk->private_data BEFORE put_disk, we have to check
+ * for NULL all over the place in open, release, check_media and
+ * revalidate, because the block level semaphore is well inside the
+ * put_disk. But we cannot zero after the call, because *disk is gone.
+ * The sd.c is blatantly racy in this area.
+ */
+ /* disk->private_data = NULL; */
+ put_disk(sc->disk);
+ sc->disk = NULL;
+
+ ub_id_put(sc->id);
+ kfree(sc);
+}
+
+/*
+ * The "command allocator".
+ */
+static struct ub_scsi_cmd *ub_get_cmd(struct ub_dev *sc)
+{
+ struct ub_scsi_cmd *ret;
+
+ if (sc->cmda[0])
+ return NULL;
+ ret = &sc->cmdv[0];
+ sc->cmda[0] = 1;
+ return ret;
+}
+
+static void ub_put_cmd(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ if (cmd != &sc->cmdv[0]) {
+ printk(KERN_WARNING "%s: releasing a foreign cmd %p\n",
+ sc->name, cmd);
+ return;
+ }
+ if (!sc->cmda[0]) {
+ printk(KERN_WARNING "%s: releasing a free cmd\n", sc->name);
+ return;
+ }
+ sc->cmda[0] = 0;
+}
+
+/*
+ * The command queue.
+ */
+static void ub_cmdq_add(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
+
+ if (t->qlen++ == 0) {
+ t->head = cmd;
+ t->tail = cmd;
+ } else {
+ t->tail->next = cmd;
+ t->tail = cmd;
+ }
+
+ if (t->qlen > t->qmax)
+ t->qmax = t->qlen;
+}
+
+static void ub_cmdq_insert(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
+
+ if (t->qlen++ == 0) {
+ t->head = cmd;
+ t->tail = cmd;
+ } else {
+ cmd->next = t->head;
+ t->head = cmd;
+ }
+
+ if (t->qlen > t->qmax)
+ t->qmax = t->qlen;
+}
+
+static struct ub_scsi_cmd *ub_cmdq_pop(struct ub_dev *sc)
+{
+ struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
+ struct ub_scsi_cmd *cmd;
+
+ if (t->qlen == 0)
+ return NULL;
+ if (--t->qlen == 0)
+ t->tail = NULL;
+ cmd = t->head;
+ t->head = cmd->next;
+ cmd->next = NULL;
+ return cmd;
+}
+
+#define ub_cmdq_peek(sc) ((sc)->cmd_queue.head)
+
+/*
+ * The request function is our main entry point
+ */
+
+static void ub_bd_rq_fn(request_queue_t *q)
+{
+ struct ub_dev *sc = q->queuedata;
+ struct request *rq;
+
+ while ((rq = elv_next_request(q)) != NULL) {
+ if (ub_bd_rq_fn_1(sc, rq) != 0) {
+ blk_stop_queue(q);
+ break;
+ }
+ }
+}
+
+static int ub_bd_rq_fn_1(struct ub_dev *sc, struct request *rq)
+{
+ struct ub_scsi_cmd *cmd;
+ int rc;
+
+ if (atomic_read(&sc->poison) || sc->changed) {
+ blkdev_dequeue_request(rq);
+ ub_end_rq(rq, 0);
+ return 0;
+ }
+
+ if ((cmd = ub_get_cmd(sc)) == NULL)
+ return -1;
+ memset(cmd, 0, sizeof(struct ub_scsi_cmd));
+
+ blkdev_dequeue_request(rq);
+
+ if (blk_pc_request(rq)) {
+ rc = ub_cmd_build_packet(sc, cmd, rq);
+ } else {
+ rc = ub_cmd_build_block(sc, cmd, rq);
+ }
+ if (rc != 0) {
+ ub_put_cmd(sc, cmd);
+ ub_end_rq(rq, 0);
+ blk_start_queue(sc->disk->queue);
+ return 0;
+ }
+
+ cmd->state = UB_CMDST_INIT;
+ cmd->done = ub_rw_cmd_done;
+ cmd->back = rq;
+
+ cmd->tag = sc->tagcnt++;
+ if ((rc = ub_submit_scsi(sc, cmd)) != 0) {
+ ub_put_cmd(sc, cmd);
+ ub_end_rq(rq, 0);
+ blk_start_queue(sc->disk->queue);
+ return 0;
+ }
+
+ return 0;
+}
+
+static int ub_cmd_build_block(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
+ struct request *rq)
+{
+ int ub_dir;
+#if 0 /* We use rq->buffer for now */
+ struct scatterlist *sg;
+ int n_elem;
+#endif
+ unsigned int block, nblks;
+
+ if (rq_data_dir(rq) == WRITE)
+ ub_dir = UB_DIR_WRITE;
+ else
+ ub_dir = UB_DIR_READ;
+
+ /*
+ * get scatterlist from block layer
+ */
+#if 0 /* We use rq->buffer for now */
+ sg = &cmd->sgv[0];
+ n_elem = blk_rq_map_sg(q, rq, sg);
+ if (n_elem <= 0) {
+ ub_put_cmd(sc, cmd);
+ ub_end_rq(rq, 0);
+ blk_start_queue(q);
+ return 0; /* request with no s/g entries? */
+ }
+
+ if (n_elem != 1) { /* Paranoia */
+ printk(KERN_WARNING "%s: request with %d segments\n",
+ sc->name, n_elem);
+ ub_put_cmd(sc, cmd);
+ ub_end_rq(rq, 0);
+ blk_start_queue(q);
+ return 0;
+ }
+#endif
+
+ /*
+ * XXX Unfortunately, this check does not work. It is quite possible
+ * to get bogus non-null rq->buffer if you allow sg by mistake.
+ */
+ if (rq->buffer == NULL) {
+ /*
+ * This must not happen if we set the queue right.
+ * The block level must create bounce buffers for us.
+ */
+ static int do_print = 1;
+ if (do_print) {
+ printk(KERN_WARNING "%s: unmapped block request"
+ " flags 0x%lx sectors %lu\n",
+ sc->name, rq->flags, rq->nr_sectors);
+ do_print = 0;
+ }
+ return -1;
+ }
+
+ /*
+ * build the command
+ *
+ * The call to blk_queue_hardsect_size() guarantees that request
+ * is aligned, but it is given in terms of 512 byte units, always.
+ */
+ block = rq->sector >> sc->capacity.bshift;
+ nblks = rq->nr_sectors >> sc->capacity.bshift;
+
+ cmd->cdb[0] = (ub_dir == UB_DIR_READ)? READ_10: WRITE_10;
+ /* 10-byte uses 4 bytes of LBA: 2147483648KB, 2097152MB, 2048GB */
+ cmd->cdb[2] = block >> 24;
+ cmd->cdb[3] = block >> 16;
+ cmd->cdb[4] = block >> 8;
+ cmd->cdb[5] = block;
+ cmd->cdb[7] = nblks >> 8;
+ cmd->cdb[8] = nblks;
+ cmd->cdb_len = 10;
+
+ cmd->dir = ub_dir;
+ cmd->data = rq->buffer;
+ cmd->len = rq->nr_sectors * 512;
+
+ return 0;
+}
+
+static int ub_cmd_build_packet(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
+ struct request *rq)
+{
+
+ if (rq->data_len != 0 && rq->data == NULL) {
+ static int do_print = 1;
+ if (do_print) {
+ printk(KERN_WARNING "%s: unmapped packet request"
+ " flags 0x%lx length %d\n",
+ sc->name, rq->flags, rq->data_len);
+ do_print = 0;
+ }
+ return -1;
+ }
+
+ memcpy(&cmd->cdb, rq->cmd, rq->cmd_len);
+ cmd->cdb_len = rq->cmd_len;
+
+ if (rq->data_len == 0) {
+ cmd->dir = UB_DIR_NONE;
+ } else {
+ if (rq_data_dir(rq) == WRITE)
+ cmd->dir = UB_DIR_WRITE;
+ else
+ cmd->dir = UB_DIR_READ;
+ }
+ cmd->data = rq->data;
+ cmd->len = rq->data_len;
+
+ return 0;
+}
+
+static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ struct request *rq = cmd->back;
+ struct gendisk *disk = sc->disk;
+ request_queue_t *q = disk->queue;
+ int uptodate;
+
+ if (blk_pc_request(rq)) {
+ /* UB_SENSE_SIZE is smaller than SCSI_SENSE_BUFFERSIZE */
+ memcpy(rq->sense, sc->top_sense, UB_SENSE_SIZE);
+ rq->sense_len = UB_SENSE_SIZE;
+ }
+
+ if (cmd->error == 0)
+ uptodate = 1;
+ else
+ uptodate = 0;
+
+ ub_put_cmd(sc, cmd);
+ ub_end_rq(rq, uptodate);
+ blk_start_queue(q);
+}
+
+static void ub_end_rq(struct request *rq, int uptodate)
+{
+ int rc;
+
+ rc = end_that_request_first(rq, uptodate, rq->hard_nr_sectors);
+ // assert(rc == 0);
+ end_that_request_last(rq);
+}
+
+/*
+ * Submit a regular SCSI operation (not an auto-sense).
+ *
+ * The Iron Law of Good Submit Routine is:
+ * Zero return - callback is done, Nonzero return - callback is not done.
+ * No exceptions.
+ *
+ * Host is assumed locked.
+ *
+ * XXX We only support Bulk for the moment.
+ */
+static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+
+ if (cmd->state != UB_CMDST_INIT ||
+ (cmd->dir != UB_DIR_NONE && cmd->len == 0)) {
+ return -EINVAL;
+ }
+
+ ub_cmdq_add(sc, cmd);
+ /*
+ * We can call ub_scsi_dispatch(sc) right away here, but it's a little
+ * safer to jump to a tasklet, in case upper layers do something silly.
+ */
+ tasklet_schedule(&sc->tasklet);
+ return 0;
+}
+
+/*
+ * Submit the first URB for the queued command.
+ * This function does not deal with queueing in any way.
+ */
+static int ub_scsi_cmd_start(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ struct bulk_cb_wrap *bcb;
+ int rc;
+
+ bcb = &sc->work_bcb;
+
+ /*
+ * ``If the allocation length is eighteen or greater, and a device
+ * server returns less than eithteen bytes of data, the application
+ * client should assume that the bytes not transferred would have been
+ * zeroes had the device server returned those bytes.''
+ *
+ * We zero sense for all commands so that when a packet request
+ * fails it does not return a stale sense.
+ */
+ memset(&sc->top_sense, 0, UB_SENSE_SIZE);
+
+ /* set up the command wrapper */
+ bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN);
+ bcb->Tag = cmd->tag; /* Endianness is not important */
+ bcb->DataTransferLength = cpu_to_le32(cmd->len);
+ bcb->Flags = (cmd->dir == UB_DIR_READ) ? 0x80 : 0;
+ bcb->Lun = 0; /* No multi-LUN yet */
+ bcb->Length = cmd->cdb_len;
+
+ /* copy the command payload */
+ memcpy(bcb->CDB, cmd->cdb, UB_MAX_CDB_SIZE);
+
+ UB_INIT_COMPLETION(sc->work_done);
+
+ sc->last_pipe = sc->send_bulk_pipe;
+ usb_fill_bulk_urb(&sc->work_urb, sc->dev, sc->send_bulk_pipe,
+ bcb, US_BULK_CB_WRAP_LEN, ub_urb_complete, sc);
+ sc->work_urb.transfer_flags = URB_ASYNC_UNLINK;
+
+ /* Fill what we shouldn't be filling, because usb-storage did so. */
+ sc->work_urb.actual_length = 0;
+ sc->work_urb.error_count = 0;
+ sc->work_urb.status = 0;
+
+ if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
+ /* XXX Clear stalls */
+ printk("ub: cmd #%d start failed (%d)\n", cmd->tag, rc); /* P3 */
+ ub_complete(&sc->work_done);
+ return rc;
+ }
+
+ sc->work_timer.expires = jiffies + UB_URB_TIMEOUT;
+ add_timer(&sc->work_timer);
+
+ cmd->state = UB_CMDST_CMD;
+ ub_cmdtr_state(sc, cmd);
+ return 0;
+}
+
+/*
+ * Timeout handler.
+ */
+static void ub_urb_timeout(unsigned long arg)
+{
+ struct ub_dev *sc = (struct ub_dev *) arg;
+ unsigned long flags;
+
+ spin_lock_irqsave(&sc->lock, flags);
+ usb_unlink_urb(&sc->work_urb);
+ spin_unlock_irqrestore(&sc->lock, flags);
+}
+
+/*
+ * Completion routine for the work URB.
+ *
+ * This can be called directly from usb_submit_urb (while we have
+ * the sc->lock taken) and from an interrupt (while we do NOT have
+ * the sc->lock taken). Therefore, bounce this off to a tasklet.
+ */
+static void ub_urb_complete(struct urb *urb, struct pt_regs *pt)
+{
+ struct ub_dev *sc = urb->context;
+
+ ub_complete(&sc->work_done);
+ tasklet_schedule(&sc->tasklet);
+}
+
+static void ub_scsi_action(unsigned long _dev)
+{
+ struct ub_dev *sc = (struct ub_dev *) _dev;
+ unsigned long flags;
+
+ spin_lock_irqsave(&sc->lock, flags);
+ del_timer(&sc->work_timer);
+ ub_scsi_dispatch(sc);
+ spin_unlock_irqrestore(&sc->lock, flags);
+}
+
+static void ub_scsi_dispatch(struct ub_dev *sc)
+{
+ struct ub_scsi_cmd *cmd;
+ int rc;
+
+ while ((cmd = ub_cmdq_peek(sc)) != NULL) {
+ if (cmd->state == UB_CMDST_DONE) {
+ ub_cmdq_pop(sc);
+ (*cmd->done)(sc, cmd);
+ } else if (cmd->state == UB_CMDST_INIT) {
+ ub_cmdtr_new(sc, cmd);
+ if ((rc = ub_scsi_cmd_start(sc, cmd)) == 0)
+ break;
+ cmd->error = rc;
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ } else {
+ if (!ub_is_completed(&sc->work_done))
+ break;
+ ub_scsi_urb_compl(sc, cmd);
+ }
+ }
+}
+
+static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ struct urb *urb = &sc->work_urb;
+ struct bulk_cs_wrap *bcs;
+ int pipe;
+ int rc;
+
+ if (atomic_read(&sc->poison)) {
+ /* A little too simplistic, I feel... */
+ goto Bad_End;
+ }
+
+ if (cmd->state == UB_CMDST_CLEAR) {
+ if (urb->status == -EPIPE) {
+ /*
+ * STALL while clearning STALL.
+ * The control pipe clears itself - nothing to do.
+ * XXX Might try to reset the device here and retry.
+ */
+ printk(KERN_NOTICE "%s: "
+ "stall on control pipe for device %u\n",
+ sc->name, sc->dev->devnum);
+ goto Bad_End;
+ }
+
+ /*
+ * We ignore the result for the halt clear.
+ */
+
+ /* reset the endpoint toggle */
+ usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
+ usb_pipeout(sc->last_pipe), 0);
+
+ ub_state_sense(sc, cmd);
+
+ } else if (cmd->state == UB_CMDST_CLR2STS) {
+ if (urb->status == -EPIPE) {
+ /*
+ * STALL while clearning STALL.
+ * The control pipe clears itself - nothing to do.
+ * XXX Might try to reset the device here and retry.
+ */
+ printk(KERN_NOTICE "%s: "
+ "stall on control pipe for device %u\n",
+ sc->name, sc->dev->devnum);
+ goto Bad_End;
+ }
+
+ /*
+ * We ignore the result for the halt clear.
+ */
+
+ /* reset the endpoint toggle */
+ usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
+ usb_pipeout(sc->last_pipe), 0);
+
+ ub_state_stat(sc, cmd);
+
+ } else if (cmd->state == UB_CMDST_CMD) {
+ if (urb->status == -EPIPE) {
+ rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
+ if (rc != 0) {
+ printk(KERN_NOTICE "%s: "
+ "unable to submit clear for device %u"
+ " (code %d)\n",
+ sc->name, sc->dev->devnum, rc);
+ /*
+ * This is typically ENOMEM or some other such shit.
+ * Retrying is pointless. Just do Bad End on it...
+ */
+ goto Bad_End;
+ }
+ cmd->state = UB_CMDST_CLEAR;
+ ub_cmdtr_state(sc, cmd);
+ return;
+ }
+ if (urb->status != 0) {
+ printk("ub: cmd #%d cmd status (%d)\n", cmd->tag, urb->status); /* P3 */
+ goto Bad_End;
+ }
+ if (urb->actual_length != US_BULK_CB_WRAP_LEN) {
+ printk("ub: cmd #%d xferred %d\n", cmd->tag, urb->actual_length); /* P3 */
+ /* XXX Must do reset here to unconfuse the device */
+ goto Bad_End;
+ }
+
+ if (cmd->dir == UB_DIR_NONE) {
+ ub_state_stat(sc, cmd);
+ return;
+ }
+
+ UB_INIT_COMPLETION(sc->work_done);
+
+ if (cmd->dir == UB_DIR_READ)
+ pipe = sc->recv_bulk_pipe;
+ else
+ pipe = sc->send_bulk_pipe;
+ sc->last_pipe = pipe;
+ usb_fill_bulk_urb(&sc->work_urb, sc->dev, pipe,
+ cmd->data, cmd->len, ub_urb_complete, sc);
+ sc->work_urb.transfer_flags = URB_ASYNC_UNLINK;
+ sc->work_urb.actual_length = 0;
+ sc->work_urb.error_count = 0;
+ sc->work_urb.status = 0;
+
+ if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
+ /* XXX Clear stalls */
+ printk("ub: data #%d submit failed (%d)\n", cmd->tag, rc); /* P3 */
+ ub_complete(&sc->work_done);
+ ub_state_done(sc, cmd, rc);
+ return;
+ }
+
+ sc->work_timer.expires = jiffies + UB_DATA_TIMEOUT;
+ add_timer(&sc->work_timer);
+
+ cmd->state = UB_CMDST_DATA;
+ ub_cmdtr_state(sc, cmd);
+
+ } else if (cmd->state == UB_CMDST_DATA) {
+ if (urb->status == -EPIPE) {
+ rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
+ if (rc != 0) {
+ printk(KERN_NOTICE "%s: "
+ "unable to submit clear for device %u"
+ " (code %d)\n",
+ sc->name, sc->dev->devnum, rc);
+ /*
+ * This is typically ENOMEM or some other such shit.
+ * Retrying is pointless. Just do Bad End on it...
+ */
+ goto Bad_End;
+ }
+ cmd->state = UB_CMDST_CLR2STS;
+ ub_cmdtr_state(sc, cmd);
+ return;
+ }
+ if (urb->status == -EOVERFLOW) {
+ /*
+ * A babble? Failure, but we must transfer CSW now.
+ */
+ cmd->error = -EOVERFLOW; /* A cheap trick... */
+ } else {
+ if (urb->status != 0)
+ goto Bad_End;
+ }
+
+ cmd->act_len = urb->actual_length;
+ ub_cmdtr_act_len(sc, cmd);
+
+ ub_state_stat(sc, cmd);
+
+ } else if (cmd->state == UB_CMDST_STAT) {
+ if (urb->status == -EPIPE) {
+ rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
+ if (rc != 0) {
+ printk(KERN_NOTICE "%s: "
+ "unable to submit clear for device %u"
+ " (code %d)\n",
+ sc->name, sc->dev->devnum, rc);
+ /*
+ * This is typically ENOMEM or some other such shit.
+ * Retrying is pointless. Just do Bad End on it...
+ */
+ goto Bad_End;
+ }
+ cmd->state = UB_CMDST_CLEAR;
+ ub_cmdtr_state(sc, cmd);
+ return;
+ }
+ if (urb->status != 0)
+ goto Bad_End;
+
+ if (urb->actual_length == 0) {
+ /*
+ * Some broken devices add unnecessary zero-length
+ * packets to the end of their data transfers.
+ * Such packets show up as 0-length CSWs. If we
+ * encounter such a thing, try to read the CSW again.
+ */
+ if (++cmd->stat_count >= 4) {
+ printk(KERN_NOTICE "%s: "
+ "unable to get CSW on device %u\n",
+ sc->name, sc->dev->devnum);
+ goto Bad_End;
+ }
+ __ub_state_stat(sc, cmd);
+ return;
+ }
+
+ /*
+ * Check the returned Bulk protocol status.
+ */
+
+ bcs = &sc->work_bcs;
+ rc = le32_to_cpu(bcs->Residue);
+ if (rc != cmd->len - cmd->act_len) {
+ /*
+ * It is all right to transfer less, the caller has
+ * to check. But it's not all right if the device
+ * counts disagree with our counts.
+ */
+ /* P3 */ printk("%s: resid %d len %d act %d\n",
+ sc->name, rc, cmd->len, cmd->act_len);
+ goto Bad_End;
+ }
+
+#if 0
+ if (bcs->Signature != cpu_to_le32(US_BULK_CS_SIGN) &&
+ bcs->Signature != cpu_to_le32(US_BULK_CS_OLYMPUS_SIGN)) {
+ /* Windows ignores signatures, so do we. */
+ }
+#endif
+
+ if (bcs->Tag != cmd->tag) {
+ /*
+ * This usually happens when we disagree with the
+ * device's microcode about something. For instance,
+ * a few of them throw this after timeouts. They buffer
+ * commands and reply at commands we timed out before.
+ * Without flushing these replies we loop forever.
+ */
+ if (++cmd->stat_count >= 4) {
+ printk(KERN_NOTICE "%s: "
+ "tag mismatch orig 0x%x reply 0x%x "
+ "on device %u\n",
+ sc->name, cmd->tag, bcs->Tag,
+ sc->dev->devnum);
+ goto Bad_End;
+ }
+ __ub_state_stat(sc, cmd);
+ return;
+ }
+
+ switch (bcs->Status) {
+ case US_BULK_STAT_OK:
+ break;
+ case US_BULK_STAT_FAIL:
+ ub_state_sense(sc, cmd);
+ return;
+ case US_BULK_STAT_PHASE:
+ /* XXX We must reset the transport here */
+ /* P3 */ printk("%s: status PHASE\n", sc->name);
+ goto Bad_End;
+ default:
+ printk(KERN_INFO "%s: unknown CSW status 0x%x\n",
+ sc->name, bcs->Status);
+ goto Bad_End;
+ }
+
+ /* Not zeroing error to preserve a babble indicator */
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ ub_cmdq_pop(sc);
+ (*cmd->done)(sc, cmd);
+
+ } else if (cmd->state == UB_CMDST_SENSE) {
+ ub_state_done(sc, cmd, -EIO);
+
+ } else {
+ printk(KERN_WARNING "%s: "
+ "wrong command state %d on device %u\n",
+ sc->name, cmd->state, sc->dev->devnum);
+ goto Bad_End;
+ }
+ return;
+
+Bad_End: /* Little Excel is dead */
+ ub_state_done(sc, cmd, -EIO);
+}
+
+/*
+ * Factorization helper for the command state machine:
+ * Finish the command.
+ */
+static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc)
+{
+
+ cmd->error = rc;
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ ub_cmdq_pop(sc);
+ (*cmd->done)(sc, cmd);
+}
+
+/*
+ * Factorization helper for the command state machine:
+ * Submit a CSW read.
+ */
+static void __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ int rc;
+
+ UB_INIT_COMPLETION(sc->work_done);
+
+ sc->last_pipe = sc->recv_bulk_pipe;
+ usb_fill_bulk_urb(&sc->work_urb, sc->dev, sc->recv_bulk_pipe,
+ &sc->work_bcs, US_BULK_CS_WRAP_LEN, ub_urb_complete, sc);
+ sc->work_urb.transfer_flags = URB_ASYNC_UNLINK;
+ sc->work_urb.actual_length = 0;
+ sc->work_urb.error_count = 0;
+ sc->work_urb.status = 0;
+
+ if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
+ /* XXX Clear stalls */
+ printk("%s: CSW #%d submit failed (%d)\n", sc->name, cmd->tag, rc); /* P3 */
+ ub_complete(&sc->work_done);
+ ub_state_done(sc, cmd, rc);
+ return;
+ }
+
+ sc->work_timer.expires = jiffies + UB_STAT_TIMEOUT;
+ add_timer(&sc->work_timer);
+}
+
+/*
+ * Factorization helper for the command state machine:
+ * Submit a CSW read and go to STAT state.
+ */
+static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ __ub_state_stat(sc, cmd);
+
+ cmd->stat_count = 0;
+ cmd->state = UB_CMDST_STAT;
+ ub_cmdtr_state(sc, cmd);
+}
+
+/*
+ * Factorization helper for the command state machine:
+ * Submit a REQUEST SENSE and go to SENSE state.
+ */
+static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ struct ub_scsi_cmd *scmd;
+ int rc;
+
+ if (cmd->cdb[0] == REQUEST_SENSE) {
+ rc = -EPIPE;
+ goto error;
+ }
+
+ scmd = &sc->top_rqs_cmd;
+ scmd->cdb[0] = REQUEST_SENSE;
+ scmd->cdb[4] = UB_SENSE_SIZE;
+ scmd->cdb_len = 6;
+ scmd->dir = UB_DIR_READ;
+ scmd->state = UB_CMDST_INIT;
+ scmd->data = sc->top_sense;
+ scmd->len = UB_SENSE_SIZE;
+ scmd->done = ub_top_sense_done;
+ scmd->back = cmd;
+
+ scmd->tag = sc->tagcnt++;
+
+ cmd->state = UB_CMDST_SENSE;
+ ub_cmdtr_state(sc, cmd);
+
+ ub_cmdq_insert(sc, scmd);
+ return;
+
+error:
+ ub_state_done(sc, cmd, rc);
+}
+
+/*
+ * A helper for the command's state machine:
+ * Submit a stall clear.
+ */
+static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
+ int stalled_pipe)
+{
+ int endp;
+ struct usb_ctrlrequest *cr;
+ int rc;
+
+ endp = usb_pipeendpoint(stalled_pipe);
+ if (usb_pipein (stalled_pipe))
+ endp |= USB_DIR_IN;
+
+ cr = &sc->work_cr;
+ cr->bRequestType = USB_RECIP_ENDPOINT;
+ cr->bRequest = USB_REQ_CLEAR_FEATURE;
+ cr->wValue = cpu_to_le16(USB_ENDPOINT_HALT);
+ cr->wIndex = cpu_to_le16(endp);
+ cr->wLength = cpu_to_le16(0);
+
+ UB_INIT_COMPLETION(sc->work_done);
+
+ usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
+ (unsigned char*) cr, NULL, 0, ub_urb_complete, sc);
+ sc->work_urb.transfer_flags = URB_ASYNC_UNLINK;
+ sc->work_urb.actual_length = 0;
+ sc->work_urb.error_count = 0;
+ sc->work_urb.status = 0;
+
+ if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
+ ub_complete(&sc->work_done);
+ return rc;
+ }
+
+ sc->work_timer.expires = jiffies + UB_CTRL_TIMEOUT;
+ add_timer(&sc->work_timer);
+ return 0;
+}
+
+/*
+ */
+static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd)
+{
+ unsigned char *sense = scmd->data;
+ struct ub_scsi_cmd *cmd;
+
+ /*
+ * Ignoring scmd->act_len, because the buffer was pre-zeroed.
+ */
+ ub_cmdtr_sense(sc, scmd, sense);
+
+ /*
+ * Find the command which triggered the unit attention or a check,
+ * save the sense into it, and advance its state machine.
+ */
+ if ((cmd = ub_cmdq_peek(sc)) == NULL) {
+ printk(KERN_WARNING "%s: sense done while idle\n", sc->name);
+ return;
+ }
+ if (cmd != scmd->back) {
+ printk(KERN_WARNING "%s: "
+ "sense done for wrong command 0x%x on device %u\n",
+ sc->name, cmd->tag, sc->dev->devnum);
+ return;
+ }
+ if (cmd->state != UB_CMDST_SENSE) {
+ printk(KERN_WARNING "%s: "
+ "sense done with bad cmd state %d on device %u\n",
+ sc->name, cmd->state, sc->dev->devnum);
+ return;
+ }
+
+ cmd->key = sense[2] & 0x0F;
+ cmd->asc = sense[12];
+ cmd->ascq = sense[13];
+
+ ub_scsi_urb_compl(sc, cmd);
+}
+
+#if 0
+/* Determine what the maximum LUN supported is */
+int usb_stor_Bulk_max_lun(struct us_data *us)
+{
+ int result;
+
+ /* issue the command */
+ result = usb_stor_control_msg(us, us->recv_ctrl_pipe,
+ US_BULK_GET_MAX_LUN,
+ USB_DIR_IN | USB_TYPE_CLASS |
+ USB_RECIP_INTERFACE,
+ 0, us->ifnum, us->iobuf, 1, HZ);
+
+ /*
+ * Some devices (i.e. Iomega Zip100) need this -- apparently
+ * the bulk pipes get STALLed when the GetMaxLUN request is
+ * processed. This is, in theory, harmless to all other devices
+ * (regardless of if they stall or not).
+ */
+ if (result < 0) {
+ usb_stor_clear_halt(us, us->recv_bulk_pipe);
+ usb_stor_clear_halt(us, us->send_bulk_pipe);
+ }
+
+ US_DEBUGP("GetMaxLUN command result is %d, data is %d\n",
+ result, us->iobuf[0]);
+
+ /* if we have a successful request, return the result */
+ if (result == 1)
+ return us->iobuf[0];
+
+ /* return the default -- no LUNs */
+ return 0;
+}
+#endif
+
+/*
+ * This is called from a process context.
+ */
+static void ub_revalidate(struct ub_dev *sc)
+{
+
+ sc->readonly = 0; /* XXX Query this from the device */
+
+ sc->capacity.nsec = 0;
+ sc->capacity.bsize = 512;
+ sc->capacity.bshift = 0;
+
+ if (ub_sync_tur(sc) != 0)
+ return; /* Not ready */
+ sc->changed = 0;
+
+ if (ub_sync_read_cap(sc, &sc->capacity) != 0) {
+ /*
+ * The retry here means something is wrong, either with the
+ * device, with the transport, or with our code.
+ * We keep this because sd.c has retries for capacity.
+ */
+ if (ub_sync_read_cap(sc, &sc->capacity) != 0) {
+ sc->capacity.nsec = 0;
+ sc->capacity.bsize = 512;
+ sc->capacity.bshift = 0;
+ }
+ }
+}
+
+/*
+ * The open funcion.
+ * This is mostly needed to keep refcounting, but also to support
+ * media checks on removable media drives.
+ */
+static int ub_bd_open(struct inode *inode, struct file *filp)
+{
+ struct gendisk *disk = inode->i_bdev->bd_disk;
+ struct ub_dev *sc;
+ unsigned long flags;
+ int rc;
+
+ if ((sc = disk->private_data) == NULL)
+ return -ENXIO;
+ spin_lock_irqsave(&ub_lock, flags);
+ if (atomic_read(&sc->poison)) {
+ spin_unlock_irqrestore(&ub_lock, flags);
+ return -ENXIO;
+ }
+ sc->openc++;
+ spin_unlock_irqrestore(&ub_lock, flags);
+
+ /*
+ * This is a workaround for a specific problem in our block layer.
+ * In 2.6.9, register_disk duplicates the code from rescan_partitions.
+ * However, if we do add_disk with a device which persistently reports
+ * a changed media, add_disk calls register_disk, which does do_open,
+ * which will call rescan_paritions for changed media. After that,
+ * register_disk attempts to do it all again and causes double kobject
+ * registration and a eventually an oops on module removal.
+ *
+ * The bottom line is, Al Viro says that we should not allow
+ * bdev->bd_invalidated to be set when doing add_disk no matter what.
+ */
+ if (sc->first_open) {
+ if (sc->changed) {
+ sc->first_open = 0;
+ rc = -ENOMEDIUM;
+ goto err_open;
+ }
+ }
+
+ if (sc->removable || sc->readonly)
+ check_disk_change(inode->i_bdev);
+
+ /*
+ * The sd.c considers ->media_present and ->changed not equivalent,
+ * under some pretty murky conditions (a failure of READ CAPACITY).
+ * We may need it one day.
+ */
+ if (sc->removable && sc->changed && !(filp->f_flags & O_NDELAY)) {
+ rc = -ENOMEDIUM;
+ goto err_open;
+ }
+
+ if (sc->readonly && (filp->f_mode & FMODE_WRITE)) {
+ rc = -EROFS;
+ goto err_open;
+ }
+
+ return 0;
+
+err_open:
+ ub_put(sc);
+ return rc;
+}
+
+/*
+ */
+static int ub_bd_release(struct inode *inode, struct file *filp)
+{
+ struct gendisk *disk = inode->i_bdev->bd_disk;
+ struct ub_dev *sc = disk->private_data;
+
+ ub_put(sc);
+ return 0;
+}
+
+/*
+ * The ioctl interface.
+ */
+static int ub_bd_ioctl(struct inode *inode, struct file *filp,
+ unsigned int cmd, unsigned long arg)
+{
+ struct gendisk *disk = inode->i_bdev->bd_disk;
+ void __user *usermem = (void __user *) arg;
+
+ return scsi_cmd_ioctl(filp, disk, cmd, usermem);
+}
+
+/*
+ * This is called once a new disk was seen by the block layer or by ub_probe().
+ * The main onjective here is to discover the features of the media such as
+ * the capacity, read-only status, etc. USB storage generally does not
+ * need to be spun up, but if we needed it, this would be the place.
+ *
+ * This call can sleep.
+ *
+ * The return code is not used.
+ */
+static int ub_bd_revalidate(struct gendisk *disk)
+{
+ struct ub_dev *sc = disk->private_data;
+
+ ub_revalidate(sc);
+ /* This is pretty much a long term P3 */
+ if (!atomic_read(&sc->poison)) { /* Cover sc->dev */
+ printk(KERN_INFO "%s: device %u capacity nsec %ld bsize %u\n",
+ sc->name, sc->dev->devnum,
+ sc->capacity.nsec, sc->capacity.bsize);
+ }
+
+ /* XXX Support sector size switching like in sr.c */
+ blk_queue_hardsect_size(disk->queue, sc->capacity.bsize);
+ set_capacity(disk, sc->capacity.nsec);
+ // set_disk_ro(sdkp->disk, sc->readonly);
+
+ return 0;
+}
+
+/*
+ * The check is called by the block layer to verify if the media
+ * is still available. It is supposed to be harmless, lightweight and
+ * non-intrusive in case the media was not changed.
+ *
+ * This call can sleep.
+ *
+ * The return code is bool!
+ */
+static int ub_bd_media_changed(struct gendisk *disk)
+{
+ struct ub_dev *sc = disk->private_data;
+
+ if (!sc->removable)
+ return 0;
+
+ /*
+ * We clean checks always after every command, so this is not
+ * as dangerous as it looks. If the TEST_UNIT_READY fails here,
+ * the device is actually not ready with operator or software
+ * intervention required. One dangerous item might be a drive which
+ * spins itself down, and come the time to write dirty pages, this
+ * will fail, then block layer discards the data. Since we never
+ * spin drives up, such devices simply cannot be used with ub anyway.
+ */
+ if (ub_sync_tur(sc) != 0) {
+ sc->changed = 1;
+ return 1;
+ }
+
+ return sc->changed;
+}
+
+static struct block_device_operations ub_bd_fops = {
+ .owner = THIS_MODULE,
+ .open = ub_bd_open,
+ .release = ub_bd_release,
+ .ioctl = ub_bd_ioctl,
+ .media_changed = ub_bd_media_changed,
+ .revalidate_disk = ub_bd_revalidate,
+};
+
+/*
+ * Common ->done routine for commands executed synchronously.
+ */
+static void ub_probe_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+ struct completion *cop = cmd->back;
+ complete(cop);
+}
+
+/*
+ * Test if the device has a check condition on it, synchronously.
+ */
+static int ub_sync_tur(struct ub_dev *sc)
+{
+ struct ub_scsi_cmd *cmd;
+ enum { ALLOC_SIZE = sizeof(struct ub_scsi_cmd) };
+ unsigned long flags;
+ struct completion compl;
+ int rc;
+
+ init_completion(&compl);
+
+ rc = -ENOMEM;
+ if ((cmd = kmalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
+ goto err_alloc;
+ memset(cmd, 0, ALLOC_SIZE);
+
+ cmd->cdb[0] = TEST_UNIT_READY;
+ cmd->cdb_len = 6;
+ cmd->dir = UB_DIR_NONE;
+ cmd->state = UB_CMDST_INIT;
+ cmd->done = ub_probe_done;
+ cmd->back = &compl;
+
+ spin_lock_irqsave(&sc->lock, flags);
+ cmd->tag = sc->tagcnt++;
+
+ rc = ub_submit_scsi(sc, cmd);
+ spin_unlock_irqrestore(&sc->lock, flags);
+
+ if (rc != 0) {
+ printk("ub: testing ready: submit error (%d)\n", rc); /* P3 */
+ goto err_submit;
+ }
+
+ wait_for_completion(&compl);
+
+ rc = cmd->error;
+
+ if (rc == -EIO && cmd->key != 0) /* Retries for benh's key */
+ rc = cmd->key;
+
+err_submit:
+ kfree(cmd);
+err_alloc:
+ return rc;
+}
+
+/*
+ * Read the SCSI capacity synchronously (for probing).
+ */
+static int ub_sync_read_cap(struct ub_dev *sc, struct ub_capacity *ret)
+{
+ struct ub_scsi_cmd *cmd;
+ char *p;
+ enum { ALLOC_SIZE = sizeof(struct ub_scsi_cmd) + 8 };
+ unsigned long flags;
+ unsigned int bsize, shift;
+ unsigned long nsec;
+ struct completion compl;
+ int rc;
+
+ init_completion(&compl);
+
+ rc = -ENOMEM;
+ if ((cmd = kmalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
+ goto err_alloc;
+ memset(cmd, 0, ALLOC_SIZE);
+ p = (char *)cmd + sizeof(struct ub_scsi_cmd);
+
+ cmd->cdb[0] = 0x25;
+ cmd->cdb_len = 10;
+ cmd->dir = UB_DIR_READ;
+ cmd->state = UB_CMDST_INIT;
+ cmd->data = p;
+ cmd->len = 8;
+ cmd->done = ub_probe_done;
+ cmd->back = &compl;
+
+ spin_lock_irqsave(&sc->lock, flags);
+ cmd->tag = sc->tagcnt++;
+
+ rc = ub_submit_scsi(sc, cmd);
+ spin_unlock_irqrestore(&sc->lock, flags);
+
+ if (rc != 0) {
+ printk("ub: reading capacity: submit error (%d)\n", rc); /* P3 */
+ goto err_submit;
+ }
+
+ wait_for_completion(&compl);
+
+ if (cmd->error != 0) {
+ printk("ub: reading capacity: error %d\n", cmd->error); /* P3 */
+ rc = -EIO;
+ goto err_read;
+ }
+ if (cmd->act_len != 8) {
+ printk("ub: reading capacity: size %d\n", cmd->act_len); /* P3 */
+ rc = -EIO;
+ goto err_read;
+ }
+
+ /* sd.c special-cases sector size of 0 to mean 512. Needed? Safe? */
+ nsec = be32_to_cpu(*(__be32 *)p) + 1;
+ bsize = be32_to_cpu(*(__be32 *)(p + 4));
+ switch (bsize) {
+ case 512: shift = 0; break;
+ case 1024: shift = 1; break;
+ case 2048: shift = 2; break;
+ case 4096: shift = 3; break;
+ default:
+ printk("ub: Bad sector size %u\n", bsize); /* P3 */
+ rc = -EDOM;
+ goto err_inv_bsize;
+ }
+
+ ret->bsize = bsize;
+ ret->bshift = shift;
+ ret->nsec = nsec << shift;
+ rc = 0;
+
+err_inv_bsize:
+err_read:
+err_submit:
+ kfree(cmd);
+err_alloc:
+ return rc;
+}
+
+/*
+ */
+static void ub_probe_urb_complete(struct urb *urb, struct pt_regs *pt)
+{
+ struct completion *cop = urb->context;
+ complete(cop);
+}
+
+static void ub_probe_timeout(unsigned long arg)
+{
+ struct completion *cop = (struct completion *) arg;
+ complete(cop);
+}
+
+/*
+ * Clear initial stalls.
+ */
+static int ub_probe_clear_stall(struct ub_dev *sc, int stalled_pipe)
+{
+ int endp;
+ struct usb_ctrlrequest *cr;
+ struct completion compl;
+ struct timer_list timer;
+ int rc;
+
+ init_completion(&compl);
+
+ endp = usb_pipeendpoint(stalled_pipe);
+ if (usb_pipein (stalled_pipe))
+ endp |= USB_DIR_IN;
+
+ cr = &sc->work_cr;
+ cr->bRequestType = USB_RECIP_ENDPOINT;
+ cr->bRequest = USB_REQ_CLEAR_FEATURE;
+ cr->wValue = cpu_to_le16(USB_ENDPOINT_HALT);
+ cr->wIndex = cpu_to_le16(endp);
+ cr->wLength = cpu_to_le16(0);
+
+ usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
+ (unsigned char*) cr, NULL, 0, ub_probe_urb_complete, &compl);
+ sc->work_urb.transfer_flags = 0;
+ sc->work_urb.actual_length = 0;
+ sc->work_urb.error_count = 0;
+ sc->work_urb.status = 0;
+
+ if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0) {
+ printk(KERN_WARNING
+ "%s: Unable to submit a probe clear (%d)\n", sc->name, rc);
+ return rc;
+ }
+
+ init_timer(&timer);
+ timer.function = ub_probe_timeout;
+ timer.data = (unsigned long) &compl;
+ timer.expires = jiffies + UB_CTRL_TIMEOUT;
+ add_timer(&timer);
+
+ wait_for_completion(&compl);
+
+ del_timer_sync(&timer);
+ usb_kill_urb(&sc->work_urb);
+
+ /* reset the endpoint toggle */
+ usb_settoggle(sc->dev, endp, usb_pipeout(sc->last_pipe), 0);
+
+ return 0;
+}
+
+/*
+ * Get the pipe settings.
+ */
+static int ub_get_pipes(struct ub_dev *sc, struct usb_device *dev,
+ struct usb_interface *intf)
+{
+ struct usb_host_interface *altsetting = intf->cur_altsetting;
+ struct usb_endpoint_descriptor *ep_in = NULL;
+ struct usb_endpoint_descriptor *ep_out = NULL;
+ struct usb_endpoint_descriptor *ep;
+ int i;
+
+ /*
+ * Find the endpoints we need.
+ * We are expecting a minimum of 2 endpoints - in and out (bulk).
+ * We will ignore any others.
+ */
+ for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
+ ep = &altsetting->endpoint[i].desc;
+
+ /* Is it a BULK endpoint? */
+ if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
+ == USB_ENDPOINT_XFER_BULK) {
+ /* BULK in or out? */
+ if (ep->bEndpointAddress & USB_DIR_IN)
+ ep_in = ep;
+ else
+ ep_out = ep;
+ }
+ }
+
+ if (ep_in == NULL || ep_out == NULL) {
+ printk(KERN_NOTICE "%s: device %u failed endpoint check\n",
+ sc->name, sc->dev->devnum);
+ return -EIO;
+ }
+
+ /* Calculate and store the pipe values */
+ sc->send_ctrl_pipe = usb_sndctrlpipe(dev, 0);
+ sc->recv_ctrl_pipe = usb_rcvctrlpipe(dev, 0);
+ sc->send_bulk_pipe = usb_sndbulkpipe(dev,
+ ep_out->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
+ sc->recv_bulk_pipe = usb_rcvbulkpipe(dev,
+ ep_in->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
+
+ return 0;
+}
+
+/*
+ * Probing is done in the process context, which allows us to cheat
+ * and not to build a state machine for the discovery.
+ */
+static int ub_probe(struct usb_interface *intf,
+ const struct usb_device_id *dev_id)
+{
+ struct ub_dev *sc;
+ request_queue_t *q;
+ struct gendisk *disk;
+ int rc;
+ int i;
+
+ rc = -ENOMEM;
+ if ((sc = kmalloc(sizeof(struct ub_dev), GFP_KERNEL)) == NULL)
+ goto err_core;
+ memset(sc, 0, sizeof(struct ub_dev));
+ spin_lock_init(&sc->lock);
+ usb_init_urb(&sc->work_urb);
+ tasklet_init(&sc->tasklet, ub_scsi_action, (unsigned long)sc);
+ atomic_set(&sc->poison, 0);
+
+ init_timer(&sc->work_timer);
+ sc->work_timer.data = (unsigned long) sc;
+ sc->work_timer.function = ub_urb_timeout;
+
+ ub_init_completion(&sc->work_done);
+ sc->work_done.done = 1; /* A little yuk, but oh well... */
+
+ rc = -ENOSR;
+ if ((sc->id = ub_id_get()) == -1)
+ goto err_id;
+ snprintf(sc->name, 8, DRV_NAME "%c", sc->id + 'a');
+
+ sc->dev = interface_to_usbdev(intf);
+ sc->intf = intf;
+ // sc->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
+
+ usb_set_intfdata(intf, sc);
+ usb_get_dev(sc->dev);
+ // usb_get_intf(sc->intf); /* Do we need this? */
+
+ /* XXX Verify that we can handle the device (from descriptors) */
+
+ ub_get_pipes(sc, sc->dev, intf);
+
+ if (device_create_file(&sc->intf->dev, &dev_attr_diag) != 0)
+ goto err_diag;
+
+ /*
+ * At this point, all USB initialization is done, do upper layer.
+ * We really hate halfway initialized structures, so from the
+ * invariants perspective, this ub_dev is fully constructed at
+ * this point.
+ */
+
+ /*
+ * This is needed to clear toggles. It is a problem only if we do
+ * `rmmod ub && modprobe ub` without disconnects, but we like that.
+ */
+ ub_probe_clear_stall(sc, sc->recv_bulk_pipe);
+ ub_probe_clear_stall(sc, sc->send_bulk_pipe);
+
+ /*
+ * The way this is used by the startup code is a little specific.
+ * A SCSI check causes a USB stall. Our common case code sees it
+ * and clears the check, after which the device is ready for use.
+ * But if a check was not present, any command other than
+ * TEST_UNIT_READY ends with a lockup (including REQUEST_SENSE).
+ *
+ * If we neglect to clear the SCSI check, the first real command fails
+ * (which is the capacity readout). We clear that and retry, but why
+ * causing spurious retries for no reason.
+ *
+ * Revalidation may start with its own TEST_UNIT_READY, but that one
+ * has to succeed, so we clear checks with an additional one here.
+ * In any case it's not our business how revaliadation is implemented.
+ */
+ for (i = 0; i < 3; i++) { /* Retries for benh's key */
+ if ((rc = ub_sync_tur(sc)) <= 0) break;
+ if (rc != 0x6) break;
+ msleep(10);
+ }
+
+ sc->removable = 1; /* XXX Query this from the device */
+ sc->changed = 1; /* ub_revalidate clears only */
+ sc->first_open = 1;
+
+ ub_revalidate(sc);
+ /* This is pretty much a long term P3 */
+ printk(KERN_INFO "%s: device %u capacity nsec %ld bsize %u\n",
+ sc->name, sc->dev->devnum, sc->capacity.nsec, sc->capacity.bsize);
+
+ /*
+ * Just one disk per sc currently, but maybe more.
+ */
+ rc = -ENOMEM;
+ if ((disk = alloc_disk(UB_MINORS_PER_MAJOR)) == NULL)
+ goto err_diskalloc;
+
+ sc->disk = disk;
+ sprintf(disk->disk_name, DRV_NAME "%c", sc->id + 'a');
+ sprintf(disk->devfs_name, DEVFS_NAME "/%c", sc->id + 'a');
+ disk->major = UB_MAJOR;
+ disk->first_minor = sc->id * UB_MINORS_PER_MAJOR;
+ disk->fops = &ub_bd_fops;
+ disk->private_data = sc;
+ disk->driverfs_dev = &intf->dev;
+
+ rc = -ENOMEM;
+ if ((q = blk_init_queue(ub_bd_rq_fn, &sc->lock)) == NULL)
+ goto err_blkqinit;
+
+ disk->queue = q;
+
+ // blk_queue_bounce_limit(q, hba[i]->pdev->dma_mask);
+ blk_queue_max_hw_segments(q, UB_MAX_REQ_SG);
+ blk_queue_max_phys_segments(q, UB_MAX_REQ_SG);
+ // blk_queue_segment_boundary(q, CARM_SG_BOUNDARY);
+ blk_queue_max_sectors(q, UB_MAX_SECTORS);
+ blk_queue_hardsect_size(q, sc->capacity.bsize);
+
+ /*
+ * This is a serious infraction, caused by a deficiency in the
+ * USB sg interface (usb_sg_wait()). We plan to remove this once
+ * we get mileage on the driver and can justify a change to USB API.
+ * See blk_queue_bounce_limit() to understand this part.
+ *
+ * XXX And I still need to be aware of the DMA mask in the HC.
+ */
+ q->bounce_pfn = blk_max_low_pfn;
+ q->bounce_gfp = GFP_NOIO;
+
+ q->queuedata = sc;
+
+ set_capacity(disk, sc->capacity.nsec);
+ if (sc->removable)
+ disk->flags |= GENHD_FL_REMOVABLE;
+
+ add_disk(disk);
+
+ return 0;
+
+err_blkqinit:
+ put_disk(disk);
+err_diskalloc:
+ device_remove_file(&sc->intf->dev, &dev_attr_diag);
+err_diag:
+ usb_set_intfdata(intf, NULL);
+ // usb_put_intf(sc->intf);
+ usb_put_dev(sc->dev);
+ ub_id_put(sc->id);
+err_id:
+ kfree(sc);
+err_core:
+ return rc;
+}
+
+static void ub_disconnect(struct usb_interface *intf)
+{
+ struct ub_dev *sc = usb_get_intfdata(intf);
+ struct gendisk *disk = sc->disk;
+ unsigned long flags;
+
+ /*
+ * Prevent ub_bd_release from pulling the rug from under us.
+ * XXX This is starting to look like a kref.
+ * XXX Why not to take this ref at probe time?
+ */
+ spin_lock_irqsave(&ub_lock, flags);
+ sc->openc++;
+ spin_unlock_irqrestore(&ub_lock, flags);
+
+ /*
+ * Fence stall clearnings, operations triggered by unlinkings and so on.
+ * We do not attempt to unlink any URBs, because we do not trust the
+ * unlink paths in HC drivers. Also, we get -84 upon disconnect anyway.
+ */
+ atomic_set(&sc->poison, 1);
+
+ /*
+ * Blow away queued commands.
+ *
+ * Actually, this never works, because before we get here
+ * the HCD terminates outstanding URB(s). It causes our
+ * SCSI command queue to advance, commands fail to submit,
+ * and the whole queue drains. So, we just use this code to
+ * print warnings.
+ */
+ spin_lock_irqsave(&sc->lock, flags);
+ {
+ struct ub_scsi_cmd *cmd;
+ int cnt = 0;
+ while ((cmd = ub_cmdq_pop(sc)) != NULL) {
+ cmd->error = -ENOTCONN;
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ ub_cmdq_pop(sc);
+ (*cmd->done)(sc, cmd);
+ cnt++;
+ }
+ if (cnt != 0) {
+ printk(KERN_WARNING "%s: "
+ "%d was queued after shutdown\n", sc->name, cnt);
+ }
+ }
+ spin_unlock_irqrestore(&sc->lock, flags);
+
+ /*
+ * Unregister the upper layer.
+ */
+ if (disk->flags & GENHD_FL_UP)
+ del_gendisk(disk);
+ /*
+ * I wish I could do:
+ * set_bit(QUEUE_FLAG_DEAD, &q->queue_flags);
+ * As it is, we rely on our internal poisoning and let
+ * the upper levels to spin furiously failing all the I/O.
+ */
+
+ /*
+ * Taking a lock on a structure which is about to be freed
+ * is very nonsensual. Here it is largely a way to do a debug freeze,
+ * and a bracket which shows where the nonsensual code segment ends.
+ *
+ * Testing for -EINPROGRESS is always a bug, so we are bending
+ * the rules a little.
+ */
+ spin_lock_irqsave(&sc->lock, flags);
+ if (sc->work_urb.status == -EINPROGRESS) { /* janitors: ignore */
+ printk(KERN_WARNING "%s: "
+ "URB is active after disconnect\n", sc->name);
+ }
+ spin_unlock_irqrestore(&sc->lock, flags);
+
+ /*
+ * There is virtually no chance that other CPU runs times so long
+ * after ub_urb_complete should have called del_timer, but only if HCD
+ * didn't forget to deliver a callback on unlink.
+ */
+ del_timer_sync(&sc->work_timer);
+
+ /*
+ * At this point there must be no commands coming from anyone
+ * and no URBs left in transit.
+ */
+
+ device_remove_file(&sc->intf->dev, &dev_attr_diag);
+ usb_set_intfdata(intf, NULL);
+ // usb_put_intf(sc->intf);
+ sc->intf = NULL;
+ usb_put_dev(sc->dev);
+ sc->dev = NULL;
+
+ ub_put(sc);
+}
+
+static struct usb_driver ub_driver = {
+ .owner = THIS_MODULE,
+ .name = "ub",
+ .probe = ub_probe,
+ .disconnect = ub_disconnect,
+ .id_table = ub_usb_ids,
+};
+
+static int __init ub_init(void)
+{
+ int rc;
+
+ /* P3 */ printk("ub: sizeof ub_scsi_cmd %zu ub_dev %zu\n",
+ sizeof(struct ub_scsi_cmd), sizeof(struct ub_dev));
+
+ if ((rc = register_blkdev(UB_MAJOR, DRV_NAME)) != 0)
+ goto err_regblkdev;
+ devfs_mk_dir(DEVFS_NAME);
+
+ if ((rc = usb_register(&ub_driver)) != 0)
+ goto err_register;
+
+ return 0;
+
+err_register:
+ devfs_remove(DEVFS_NAME);
+ unregister_blkdev(UB_MAJOR, DRV_NAME);
+err_regblkdev:
+ return rc;
+}
+
+static void __exit ub_exit(void)
+{
+ usb_deregister(&ub_driver);
+
+ devfs_remove(DEVFS_NAME);
+ unregister_blkdev(UB_MAJOR, DRV_NAME);
+}
+
+module_init(ub_init);
+module_exit(ub_exit);
+
+MODULE_LICENSE("GPL");