drivers/block/ub.c #6

From: Pete Zaitcev
Date: Fri Jul 30 2004 - 05:56:46 EST


Same as before, but it's at least semi-useful now. I actually would consider
it mergeable as EXPERIMENTAL, but for one thing: I did not ask LANANA for
a major. Instead I would like to try some sort of fully dynamic allocation
using udev. It looks like a good opportunity to learn about udev.

The next step is to add ioctls to burn CDs, and to clone ub.c into ufi.c
with corresponding refactoring of common pieces into a library like libata.
It would be neat if someone othen than I did that, to validate the
readability, but I'm not holding my breath.

I wish this could be somehow limited to flash keys, but I don't see a way.
Without such limit or ioctls, ub cannot be used by distributions at present.

-- Pete

Same as #5, plus added support for removable storage (flash cards).
For the moment, the removable flag is hardwired to 1.

diff -urpN -X dontdiff linux-2.6.7/drivers/block/Kconfig linux-2.6.7-ub/drivers/block/Kconfig
--- linux-2.6.7/drivers/block/Kconfig 2004-06-16 16:53:48.000000000 -0700
+++ linux-2.6.7-ub/drivers/block/Kconfig 2004-07-29 19:55:48.000000000 -0700
@@ -301,6 +301,15 @@ config BLK_DEV_CARMEL

Use devices /dev/carmel/$N and /dev/carmel/$Np$M.

+config BLK_DEV_UB
+ tristate "Low Performance USB Block driver"
+ depends on USB
+ help
+ This driver supports certain USB attached storage devices
+ such as flash keys.
+
+ If unsure, say N.
+
config BLK_DEV_RAM
tristate "RAM disk support"
---help---
diff -urpN -X dontdiff linux-2.6.7/drivers/block/Makefile linux-2.6.7-ub/drivers/block/Makefile
--- linux-2.6.7/drivers/block/Makefile 2004-05-10 17:39:54.000000000 -0700
+++ linux-2.6.7-ub/drivers/block/Makefile 2004-07-26 00:00:21.000000000 -0700
@@ -42,4 +42,5 @@ obj-$(CONFIG_BLK_DEV_CRYPTOLOOP) += cryp

obj-$(CONFIG_VIODASD) += viodasd.o
obj-$(CONFIG_BLK_DEV_CARMEL) += carmel.o
+obj-$(CONFIG_BLK_DEV_UB) += ub.o

diff -urpN -X dontdiff linux-2.6.7/drivers/block/ub.c linux-2.6.7-ub/drivers/block/ub.c
--- linux-2.6.7/drivers/block/ub.c 1969-12-31 16:00:00.000000000 -0800
+++ linux-2.6.7-ub/drivers/block/ub.c 2004-07-30 03:21:12.024123357 -0700
@@ -0,0 +1,1919 @@
+/*
+ * The low performance USB storage driver (ub).
+ *
+ * Copyright (c) 1999, 2000 Matthew Dharm (mdharm-usb@xxxxxxxxxxxxxxxxxx)
+ * Copyright (C) 2004 Pete Zaitcev (zaitcev@xxxxxxxxx)
+ *
+ * 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)
+ * -- 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
+ * -- normal queue instead of sc->busy and friends (needed for revalidation)
+ * -- do something about spin-down devices, they are extremely dangerous
+ * (we need to find one first though)
+ * -- verify the 13 conditions and do bulk resets
+ * -- normal pool of commands instead of cmdv[]?
+ * -- 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
+ */
+#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
+
+/*
+ * 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 {
+ u32 Signature; /* contains 'USBC' */
+ u32 Tag; /* unique per command id */
+ u32 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 {
+ u32 Signature; /* should = 'USBS' */
+ u32 Tag; /* same as original command */
+ u32 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 ought to be enough for a 32K transfer (UB_MAX_SECTORS)
+ * even if a webcam hogs the bus (famous last words).
+ * Some CDs need a second to spin up though.
+ */
+#define UB_URB_TIMEOUT (HZ*2)
+#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. */
+ enum ub_scsi_cmd_state state;
+ unsigned int tag;
+ unsigned int trace_index;
+
+ int error; /* Return code - valid upon done */
+ int act_len; /* Return size */
+
+ 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 15
+
+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];
+};
+
+/*
+ * 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;
+ 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 urb_tasklet;
+
+ /* XXX Use Ingo's mempool (once we have more than one) */
+ int cmda[1];
+ struct ub_scsi_cmd cmdv[1];
+
+ int busy;
+ struct ub_scsi_cmd *top_cmd; /* XXX Under ->busy until we have a queue */
+ struct ub_scsi_cmd top_rqs_cmd; /* REQUEST SENSE */
+ unsigned char top_sense[UB_SENSE_SIZE];
+
+ struct urb work_urb;
+ 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_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_scsi_urb_complete(struct urb *urb, struct pt_regs *pt);
+static void ub_scsi_urb_action(unsigned long _dev);
+static void ub_scsi_urb_compl(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 spinlock_t ub_lock = SPIN_LOCK_UNLOCKED; /* 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);
+ 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)
+{
+
+ if (id < 0 || id >= UB_MAX_HOSTS) {
+ printk(KERN_ERR DRV_NAME ": bad host ID %d\n", id);
+ return;
+ }
+ if (ub_hostv[id] == 0) {
+ printk(KERN_ERR DRV_NAME ": freeing free host ID %d\n", id);
+ return;
+ }
+ ub_hostv[id] = 0;
+}
+
+/*
+ * Final cleanup and deallocation.
+ * This must be called with ub_lock taken.
+ */
+static void ub_cleanup(struct ub_dev *sc)
+{
+ 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 request function is our main entry point
+ */
+
+static inline int ub_bd_rq_fn_1(request_queue_t *q)
+{
+#if 0
+ int writing = 0, pci_dir, i, n_elem;
+ u32 tmp;
+ unsigned int msg_size;
+#endif
+ struct ub_dev *sc = q->queuedata;
+ struct request *rq;
+#if 0 /* We use rq->buffer for now */
+ struct scatterlist *sg;
+ int n_elem;
+#endif
+ struct ub_scsi_cmd *cmd;
+ int ub_dir;
+ unsigned int block, nblks;
+ int rc;
+
+ if ((rq = elv_next_request(q)) == NULL)
+ return 1;
+
+ 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) {
+ blk_stop_queue(q);
+ return 1;
+ }
+
+ blkdev_dequeue_request(rq);
+
+ 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 request\n", sc->name);
+ do_print = 0;
+ }
+ ub_put_cmd(sc, cmd);
+ ub_end_rq(rq, 0);
+ blk_start_queue(q);
+ return 0;
+ }
+
+ /*
+ * build the command
+ */
+ block = rq->sector;
+ nblks = rq->nr_sectors;
+
+ memset(cmd, 0, sizeof(struct ub_scsi_cmd));
+ 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->state = UB_CMDST_INIT;
+ cmd->data = rq->buffer;
+ cmd->len = nblks * 512;
+ 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(q);
+ return 0;
+ }
+
+ return 0;
+}
+
+static void ub_bd_rq_fn(request_queue_t *q)
+{
+ do { } while (ub_bd_rq_fn_1(q) == 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 (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 SCSI operation.
+ *
+ * This is only called customarily from a soft interrupt or a process,
+ * so it can call back without worrying about a recursion.
+ *
+ * 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)
+{
+ struct bulk_cb_wrap *bcb;
+ int rc;
+
+ /*
+ * We do not trap into BUG() here because the consequences are
+ * sporadic stack overflows. Better to warn than to die outright.
+ */
+ if (in_irq()) {
+ static int first_warning = 1;
+ if (first_warning) {
+ printk(KERN_WARNING DRV_NAME ": "
+ "submitting command from a hard irq\n");
+ first_warning = 0;
+ }
+ }
+
+ /* XXX Set up a queue */
+ if (cmd != &sc->top_rqs_cmd) { /* XXX This is getting out of hand. */
+ if (sc->busy)
+ return -EBUSY;
+ sc->busy = 1;
+ sc->top_cmd = cmd;
+ } else {
+ if (!sc->busy) {
+ return -EBUSY;
+ }
+ }
+
+ ub_cmdtr_new(sc, cmd);
+
+ if (cmd->state != UB_CMDST_INIT ||
+ (cmd->dir != UB_DIR_NONE && cmd->len == 0)) {
+ sc->top_cmd = NULL;
+ sc->busy = 0;
+ return -EINVAL;
+ }
+
+ bcb = &sc->work_bcb;
+
+ /* 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);
+
+ 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_scsi_urb_complete, sc);
+ sc->work_urb.timeout = UB_URB_TIMEOUT;
+
+ /* 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 submit failed (%d)\n", cmd->tag, rc); /* P3 */
+
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ sc->busy = 0;
+ sc->top_cmd = NULL;
+ return rc;
+ }
+
+ cmd->state = UB_CMDST_CMD;
+ ub_cmdtr_state(sc, cmd);
+ return 0;
+}
+
+/*
+ * 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_scsi_urb_complete(struct urb *urb, struct pt_regs *pt)
+{
+ struct ub_dev *sc = urb->context;
+
+ tasklet_schedule(&sc->urb_tasklet);
+}
+
+static void ub_scsi_urb_action(unsigned long _dev)
+{
+ struct ub_dev *sc = (struct ub_dev *) _dev;
+ unsigned long flags;
+ struct ub_scsi_cmd *cmd;
+
+ spin_lock_irqsave(&sc->lock, flags);
+ if (sc->busy) {
+ cmd = sc->top_cmd;
+ if (cmd->state == UB_CMDST_SENSE) { /* XXX Kludgy */
+ cmd = &sc->top_rqs_cmd;
+ }
+ ub_scsi_urb_compl(sc, cmd);
+ } else {
+ /* Never happens */
+ /* P3 */ printk("ub: Action on idle device\n");
+ }
+ spin_unlock_irqrestore(&sc->lock, flags);
+}
+
+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;
+
+/* P3 */ /** printk("ub: urb status %d pipe 0x%08x len %d act %d\n",
+ urb->status, urb->pipe, urb->transfer_buffer_length, urb->actual_length); **/
+
+ 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.
+ * A STALL is illegal on a control pipe!
+ * 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 toggles and endpoint flags */
+ usb_endpoint_running(sc->dev, usb_pipeendpoint(sc->last_pipe),
+ usb_pipeout(sc->last_pipe));
+ 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.
+ * A STALL is illegal on a control pipe!
+ * 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 toggles and endpoint flags */
+ usb_endpoint_running(sc->dev, usb_pipeendpoint(sc->last_pipe),
+ usb_pipeout(sc->last_pipe));
+ 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 (%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 != US_BULK_CB_WRAP_LEN) {
+ /* XXX Must do reset here to unconfuse the device */
+ goto Bad_End;
+ }
+
+ if (cmd->dir == UB_DIR_NONE) {
+ ub_state_stat(sc, cmd);
+ return;
+ }
+
+ 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_scsi_urb_complete, sc);
+ sc->work_urb.timeout = UB_URB_TIMEOUT;
+ 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 */
+
+ cmd->error = rc;
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ if (cmd != &sc->top_rqs_cmd) { /* XXX This is getting out of hand. */
+ sc->busy = 0;
+ sc->top_cmd = NULL;
+ }
+ (*cmd->done)(sc, cmd);
+ return;
+ }
+
+ 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 (%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 (%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 only not dropping the count...
+ */
+ 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_scsi_urb_complete, sc);
+ sc->work_urb.timeout = UB_URB_TIMEOUT;
+ sc->work_urb.actual_length = 0;
+ sc->work_urb.error_count = 0;
+ sc->work_urb.status = 0;
+
+ rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC);
+ if (rc != 0) {
+ /* XXX Clear stalls */
+ printk("%s: CSW #%d submit failed (%d)\n",
+ sc->name, cmd->tag, rc); /* P3 */
+
+ cmd->error = rc;
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ if (cmd != &sc->top_rqs_cmd) { /* XXX This is getting out of hand. */
+ sc->busy = 0;
+ sc->top_cmd = NULL;
+ }
+ (*cmd->done)(sc, cmd);
+ return;
+ }
+ 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("ub: resid %d len %d act %d\n",
+ rc, cmd->len, cmd->act_len);
+ goto Bad_End;
+ }
+
+ if (bcs->Signature != cpu_to_le32(US_BULK_CS_SIGN) &&
+ bcs->Signature != cpu_to_le32(US_BULK_CS_OLYMPUS_SIGN)) {
+ /* XXX Rate-limit, even for P3 tagged */
+ /* P3 */ printk("ub: signature 0x%x\n", bcs->Signature);
+ /* Windows ignores signatures, so do we. */
+ }
+
+ if (bcs->Tag != cmd->tag) {
+ /* P3 */ printk("ub: tag orig 0x%x reply 0x%x\n",
+ cmd->tag, bcs->Tag);
+ goto Bad_End;
+ }
+
+ 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("ub: status PHASE\n");
+ goto Bad_End;
+ default:
+ printk(KERN_INFO "%s: unknown CSW status 0x%x\n",
+ sc->name, bcs->Status);
+ goto Bad_End;
+ }
+
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ if (cmd != &sc->top_rqs_cmd) { /* XXX This is getting out of hand. */
+ sc->busy = 0;
+ sc->top_cmd = NULL;
+ }
+ (*cmd->done)(sc, cmd);
+
+ } else if (cmd->state == UB_CMDST_SENSE) {
+ /*
+ * We do not look at sense, because even if there was no sense,
+ * we get into UB_CMDST_SENSE from a STALL or CSW FAIL only.
+ * We request sense because we want to clear CHECK CONDITION
+ * on devices with delusions of SCSI, and not because we
+ * are curious in any way about the sense itself.
+ */
+ /* if ((cmd->top_sense[2] & 0x0F) == NO_SENSE) { foo } */
+
+ cmd->error = -EIO;
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ if (cmd != &sc->top_rqs_cmd) { /* XXX This is getting out of hand. */
+ sc->busy = 0;
+ sc->top_cmd = NULL;
+ }
+ (*cmd->done)(sc, cmd);
+ } 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 */
+ cmd->error = -EIO;
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ if (cmd != &sc->top_rqs_cmd) { /* XXX This is getting out of hand. */
+ sc->busy = 0;
+ sc->top_cmd = NULL;
+ }
+ (*cmd->done)(sc, cmd);
+}
+
+/*
+ * 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)
+{
+ int rc;
+
+ 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_scsi_urb_complete, sc);
+ sc->work_urb.timeout = UB_URB_TIMEOUT;
+ 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: CSW #%d submit failed (%d)\n", cmd->tag, rc); /* P3 */
+
+ cmd->error = rc;
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ if (cmd != &sc->top_rqs_cmd) { /* XXX This is getting out of hand. */
+ sc->busy = 0;
+ sc->top_cmd = NULL;
+ }
+ (*cmd->done)(sc, cmd);
+ return;
+ }
+
+ 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;
+ }
+
+ memset(&sc->top_sense, 0, UB_SENSE_SIZE);
+ scmd = &sc->top_rqs_cmd;
+ scmd->cdb[0] = REQUEST_SENSE;
+ 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++;
+ if ((rc = ub_submit_scsi(sc, scmd)) != 0) {
+ printk(KERN_NOTICE "%s: "
+ "unable to submit sense for device %u (%d)\n",
+ sc->name, sc->dev->devnum, rc);
+ rc = -EIO;
+ goto error;
+ }
+
+ cmd->state = UB_CMDST_SENSE;
+ ub_cmdtr_state(sc, cmd);
+ return;
+
+error:
+ cmd->error = rc;
+ cmd->state = UB_CMDST_DONE;
+ ub_cmdtr_state(sc, cmd);
+ if (cmd != &sc->top_rqs_cmd) { /* XXX This is getting out of hand. */
+ sc->busy = 0;
+ sc->top_cmd = NULL;
+ }
+ (*cmd->done)(sc, cmd);
+}
+
+/*
+ * 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;
+
+ 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_scsi_urb_complete, sc);
+ sc->work_urb.timeout = UB_CTRL_TIMEOUT;
+ sc->work_urb.actual_length = 0;
+ sc->work_urb.error_count = 0;
+ sc->work_urb.status = 0;
+
+ return usb_submit_urb(&sc->work_urb, GFP_ATOMIC);
+}
+
+/*
+ */
+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;
+
+ ub_cmdtr_sense(sc, scmd, sense);
+
+ if (!sc->busy) { /* P3 */
+ printk(KERN_WARNING "%s: sense done while idle\n", sc->name);
+ return;
+ }
+ cmd = scmd->back;
+ 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;
+ }
+
+ 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->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 = 100;
+ sc->capacity.bsize = 512;
+ sc->capacity.bshift = 0;
+ }
+ }
+
+ /* XXX Set these to some reasonable values. */
+ sc->readonly = 0;
+ sc->removable = 1;
+}
+
+/*
+ * 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);
+
+ if (sc->removable || sc->readonly)
+ check_disk_change(inode->i_bdev);
+
+ /* XXX sd.c and floppy.c bail on open if media is not present. */
+
+ if (sc->readonly && (filp->f_mode & FMODE_WRITE)) {
+ rc = -EROFS;
+ goto err_open;
+ }
+
+ return 0;
+
+err_open:
+ spin_lock_irqsave(&ub_lock, flags);
+ --sc->openc;
+ if (sc->openc == 0 && atomic_read(&sc->poison))
+ ub_cleanup(sc);
+ spin_unlock_irqrestore(&ub_lock, flags);
+ 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;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ub_lock, flags);
+ --sc->openc;
+ if (sc->openc == 0 && atomic_read(&sc->poison))
+ ub_cleanup(sc);
+ spin_unlock_irqrestore(&ub_lock, flags);
+ return 0;
+}
+
+/*
+ * The ioctl interface.
+ */
+static int ub_bd_ioctl(struct inode *inode, struct file *filp,
+ unsigned int cmd, unsigned long arg)
+{
+// void __user *usermem = (void *) arg;
+// struct carm_port *port = ino->i_bdev->bd_disk->private_data;
+// struct hd_geometry geom;
+
+#if 0
+ switch (cmd) {
+ case HDIO_GETGEO:
+ if (usermem == NULL) // XXX Bizzare. Why?
+ return -EINVAL;
+
+ geom.heads = (u8) port->dev_geom_head;
+ geom.sectors = (u8) port->dev_geom_sect;
+ geom.cylinders = port->dev_geom_cyl;
+ geom.start = get_start_sect(ino->i_bdev);
+
+ if (copy_to_user(usermem, &geom, sizeof(geom)))
+ return -EFAULT;
+ return 0;
+
+ default: ;
+ }
+#endif
+
+ return -ENOTTY;
+}
+
+/*
+ * 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 */
+ printk(KERN_INFO "%s: device %u capacity nsec %ld bsize %u\n",
+ sc->name, sc->dev->devnum, sc->capacity.nsec, 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;
+ /* P3 */ printk("%s: made changed\n", sc->name);
+ return 1;
+ }
+
+ /* The sd.c clears this before returning (one-shot flag). Why? */
+ /* P3 */ printk("%s: %s changed\n", sc->name,
+ sc->changed? "is": "was not");
+ 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;
+
+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(*(u32 *)p) + 1;
+ bsize = be32_to_cpu(*(u32 *)(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);
+}
+
+/*
+ * 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;
+ 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.timeout = UB_CTRL_TIMEOUT;
+ 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;
+ }
+
+ wait_for_completion(&compl);
+
+ /* reset the toggles and endpoint flags */
+ usb_endpoint_running(sc->dev, endp, usb_pipeout(sc->last_pipe));
+ 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;
+
+ 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->urb_tasklet, ub_scsi_urb_action, (unsigned long)sc);
+ atomic_set(&sc->poison, 0);
+
+ 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.
+ */
+ ub_sync_tur(sc);
+
+ 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;
+
+ 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, xxxxx);
+
+ /*
+ * 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);
+ spin_lock_irq(&ub_lock);
+ ub_id_put(sc->id);
+ spin_unlock_irq(&ub_lock);
+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;
+ request_queue_t *q = disk->queue;
+ unsigned long 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);
+
+ /*
+ * Unregister the upper layer, this waits for all commands to end.
+ */
+ if (disk->flags & GENHD_FL_UP)
+ del_gendisk(disk);
+ if (q)
+ 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(disk);
+ sc->disk = NULL;
+
+ /*
+ * We really expect blk_cleanup_queue() to wait, so no amount
+ * of paranoya is too much.
+ *
+ * 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->busy) {
+ printk(KERN_WARNING "%s: "
+ "command is active after disconnect, status %d\n",
+ sc->name, sc->top_cmd->state);
+ }
+ 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);
+
+ /*
+ * 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;
+
+ spin_lock_irqsave(&ub_lock, flags);
+ if (sc->openc == 0)
+ ub_cleanup(sc);
+ spin_unlock_irqrestore(&ub_lock, flags);
+}
+
+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 %u ub_dev %u\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");
diff -urpN -X dontdiff linux-2.6.7/drivers/usb/storage/unusual_devs.h linux-2.6.7-ub/drivers/usb/storage/unusual_devs.h
--- linux-2.6.7/drivers/usb/storage/unusual_devs.h 2004-06-16 16:53:59.000000000 -0700
+++ linux-2.6.7-ub/drivers/usb/storage/unusual_devs.h 2004-07-26 00:00:21.000000000 -0700
@@ -486,11 +486,13 @@ UNUSUAL_DEV( 0x0781, 0x0001, 0x0200, 0x
US_SC_SCSI, US_PR_CB, NULL,
US_FL_SINGLE_LUN ),

+#if !defined(CONFIG_BLK_DEV_UB) && !defined(CONFIG_BLK_DEV_UB_MODULE)
UNUSUAL_DEV( 0x0781, 0x0002, 0x0009, 0x0009,
"Sandisk",
"ImageMate SDDR-31",
US_SC_DEVICE, US_PR_DEVICE, NULL,
US_FL_IGNORE_SER ),
+#endif

UNUSUAL_DEV( 0x0781, 0x0100, 0x0100, 0x0100,
"Sandisk",
diff -urpN -X dontdiff linux-2.6.7/drivers/usb/storage/usb.c linux-2.6.7-ub/drivers/usb/storage/usb.c
--- linux-2.6.7/drivers/usb/storage/usb.c 2004-06-16 16:53:59.000000000 -0700
+++ linux-2.6.7-ub/drivers/usb/storage/usb.c 2004-07-26 00:00:21.000000000 -0700
@@ -133,7 +133,9 @@ static struct usb_device_id storage_usb_
{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_QIC, US_PR_BULK) },
{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_UFI, US_PR_BULK) },
{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_8070, US_PR_BULK) },
+#if !defined(CONFIG_BLK_DEV_UB) && !defined(CONFIG_BLK_DEV_UB_MODULE)
{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_SCSI, US_PR_BULK) },
+#endif

/* Terminating entry */
{ }
@@ -207,8 +209,10 @@ static struct us_unusual_dev us_unusual_
.useTransport = US_PR_BULK},
{ .useProtocol = US_SC_8070,
.useTransport = US_PR_BULK},
+#if !defined(CONFIG_BLK_DEV_UB) && !defined(CONFIG_BLK_DEV_UB_MODULE)
{ .useProtocol = US_SC_SCSI,
.useTransport = US_PR_BULK},
+#endif

/* Terminating entry */
{ 0 }
diff -urpN -X dontdiff linux-2.6.7/include/linux/major.h linux-2.6.7-ub/include/linux/major.h
--- linux-2.6.7/include/linux/major.h 2004-04-21 12:01:24.000000000 -0700
+++ linux-2.6.7-ub/include/linux/major.h 2004-07-26 00:00:21.000000000 -0700
@@ -165,4 +165,6 @@

#define VIOTAPE_MAJOR 230

+#define UB_MAJOR 125 /* USB Block - Experimental XXX */
+
#endif
-
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