* ro setting are not allowed when the medium is loaded or if CD-ROM
* emulation is being used.
*
+ * When a LUN receive an "eject" SCSI request (Start/Stop Unit),
+ * if the LUN is removable, the backing file is released to simulate
+ * ejection.
+ *
*
* This function is heavily based on "File-backed Storage Gadget" by
* Alan Stern which in turn is heavily based on "Gadget Zero" by David
#define FSG_NO_INTR_EP 1
-#define FSG_BUFFHD_STATIC_BUFFER 1
#define FSG_NO_DEVICE_STRINGS 1
#define FSG_NO_OTG 1
#define FSG_NO_INTR_EP 1
/* Data shared by all the FSG instances. */
struct fsg_common {
struct usb_gadget *gadget;
- struct fsg_dev *fsg;
- struct fsg_dev *prev_fsg;
+ struct fsg_dev *fsg, *new_fsg;
+ wait_queue_head_t fsg_wait;
/* filesem protects: backing files in use */
struct rw_semaphore filesem;
enum fsg_state state; /* For exception handling */
unsigned int exception_req_tag;
- u8 config, new_config;
enum data_direction data_dir;
u32 data_size;
u32 data_size_from_cmnd;
u16 w_value = le16_to_cpu(ctrl->wValue);
u16 w_length = le16_to_cpu(ctrl->wLength);
- if (!fsg->common->config)
+ if (!fsg_is_set(fsg->common))
return -EOPNOTSUPP;
switch (ctrl->bRequest) {
static int do_start_stop(struct fsg_common *common)
{
- if (!common->curlun) {
+ struct fsg_lun *curlun = common->curlun;
+ int loej, start;
+
+ if (!curlun) {
return -EINVAL;
- } else if (!common->curlun->removable) {
- common->curlun->sense_data = SS_INVALID_COMMAND;
+ } else if (!curlun->removable) {
+ curlun->sense_data = SS_INVALID_COMMAND;
return -EINVAL;
}
+
+ loej = common->cmnd[4] & 0x02;
+ start = common->cmnd[4] & 0x01;
+
+ /* eject code from file_storage.c:do_start_stop() */
+
+ if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
+ (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
+ curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
+ return -EINVAL;
+ }
+
+ if (!start) {
+ /* Are we allowed to unload the media? */
+ if (curlun->prevent_medium_removal) {
+ LDBG(curlun, "unload attempt prevented\n");
+ curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
+ return -EINVAL;
+ }
+ if (loej) { /* Simulate an unload/eject */
+ up_read(&common->filesem);
+ down_write(&common->filesem);
+ fsg_lun_close(curlun);
+ up_write(&common->filesem);
+ down_read(&common->filesem);
+ }
+ } else {
+
+ /* Our emulation doesn't support mounting; the medium is
+ * available for use as soon as it is loaded. */
+ if (!fsg_lun_is_open(curlun)) {
+ curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
+ return -EINVAL;
+ }
+ }
return 0;
}
return -ENOMEM;
}
-/*
- * Reset interface setting and re-init endpoint state (toggle etc).
- * Call with altsetting < 0 to disable the interface. The only other
- * available altsetting is 0, which enables the interface.
- */
-static int do_set_interface(struct fsg_common *common, int altsetting)
+/* Reset interface setting and re-init endpoint state (toggle etc). */
+static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
{
- int rc = 0;
- int i;
- const struct usb_endpoint_descriptor *d;
+ const struct usb_endpoint_descriptor *d;
+ struct fsg_dev *fsg;
+ int i, rc = 0;
if (common->running)
DBG(common, "reset interface\n");
reset:
/* Deallocate the requests */
- if (common->prev_fsg) {
- struct fsg_dev *fsg = common->prev_fsg;
+ if (common->fsg) {
+ fsg = common->fsg;
for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
struct fsg_buffhd *bh = &common->buffhds[i];
fsg->bulk_out_enabled = 0;
}
- common->prev_fsg = 0;
+ common->fsg = NULL;
+ wake_up(&common->fsg_wait);
}
common->running = 0;
- if (altsetting < 0 || rc != 0)
+ if (!new_fsg || rc)
return rc;
- DBG(common, "set interface %d\n", altsetting);
+ common->fsg = new_fsg;
+ fsg = common->fsg;
+
+ /* Enable the endpoints */
+ d = fsg_ep_desc(common->gadget,
+ &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
+ rc = enable_endpoint(common, fsg->bulk_in, d);
+ if (rc)
+ goto reset;
+ fsg->bulk_in_enabled = 1;
+
+ d = fsg_ep_desc(common->gadget,
+ &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
+ rc = enable_endpoint(common, fsg->bulk_out, d);
+ if (rc)
+ goto reset;
+ fsg->bulk_out_enabled = 1;
+ common->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
+ clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
- if (fsg_is_set(common)) {
- struct fsg_dev *fsg = common->fsg;
- common->prev_fsg = common->fsg;
+ /* Allocate the requests */
+ for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
+ struct fsg_buffhd *bh = &common->buffhds[i];
- /* Enable the endpoints */
- d = fsg_ep_desc(common->gadget,
- &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
- rc = enable_endpoint(common, fsg->bulk_in, d);
+ rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
if (rc)
goto reset;
- fsg->bulk_in_enabled = 1;
-
- d = fsg_ep_desc(common->gadget,
- &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
- rc = enable_endpoint(common, fsg->bulk_out, d);
+ rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
if (rc)
goto reset;
- fsg->bulk_out_enabled = 1;
- common->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
- clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
-
- /* Allocate the requests */
- for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
- struct fsg_buffhd *bh = &common->buffhds[i];
-
- rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
- if (rc)
- goto reset;
- rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
- if (rc)
- goto reset;
- bh->inreq->buf = bh->outreq->buf = bh->buf;
- bh->inreq->context = bh->outreq->context = bh;
- bh->inreq->complete = bulk_in_complete;
- bh->outreq->complete = bulk_out_complete;
- }
-
- common->running = 1;
- for (i = 0; i < common->nluns; ++i)
- common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
- return rc;
- } else {
- return -EIO;
+ bh->inreq->buf = bh->outreq->buf = bh->buf;
+ bh->inreq->context = bh->outreq->context = bh;
+ bh->inreq->complete = bulk_in_complete;
+ bh->outreq->complete = bulk_out_complete;
}
-}
-
-
-/*
- * Change our operational configuration. This code must agree with the code
- * that returns config descriptors, and with interface altsetting code.
- *
- * It's also responsible for power management interactions. Some
- * configurations might not work with our current power sources.
- * For now we just assume the gadget is always self-powered.
- */
-static int do_set_config(struct fsg_common *common, u8 new_config)
-{
- int rc = 0;
- /* Disable the single interface */
- if (common->config != 0) {
- DBG(common, "reset config\n");
- common->config = 0;
- rc = do_set_interface(common, -1);
- }
-
- /* Enable the interface */
- if (new_config != 0) {
- common->config = new_config;
- rc = do_set_interface(common, 0);
- if (rc != 0)
- common->config = 0; /* Reset on errors */
- }
+ common->running = 1;
+ for (i = 0; i < common->nluns; ++i)
+ common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
return rc;
}
static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
{
struct fsg_dev *fsg = fsg_from_func(f);
- fsg->common->prev_fsg = fsg->common->fsg;
- fsg->common->fsg = fsg;
- fsg->common->new_config = 1;
+ fsg->common->new_fsg = fsg;
raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
return 0;
}
static void fsg_disable(struct usb_function *f)
{
struct fsg_dev *fsg = fsg_from_func(f);
- fsg->common->prev_fsg = fsg->common->fsg;
- fsg->common->fsg = fsg;
- fsg->common->new_config = 0;
+ fsg->common->new_fsg = NULL;
raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
}
static void handle_exception(struct fsg_common *common)
{
siginfo_t info;
- int sig;
int i;
struct fsg_buffhd *bh;
enum fsg_state old_state;
- u8 new_config;
struct fsg_lun *curlun;
unsigned int exception_req_tag;
- int rc;
/* Clear the existing signals. Anything but SIGUSR1 is converted
* into a high-priority EXIT exception. */
for (;;) {
- sig = dequeue_signal_lock(current, ¤t->blocked, &info);
+ int sig =
+ dequeue_signal_lock(current, ¤t->blocked, &info);
if (!sig)
break;
if (sig != SIGUSR1) {
}
/* Cancel all the pending transfers */
- if (fsg_is_set(common)) {
+ if (likely(common->fsg)) {
for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
bh = &common->buffhds[i];
if (bh->inreq_busy)
common->next_buffhd_to_fill = &common->buffhds[0];
common->next_buffhd_to_drain = &common->buffhds[0];
exception_req_tag = common->exception_req_tag;
- new_config = common->new_config;
old_state = common->state;
if (old_state == FSG_STATE_ABORT_BULK_OUT)
break;
case FSG_STATE_CONFIG_CHANGE:
- rc = do_set_config(common, new_config);
+ do_set_interface(common, common->new_fsg);
break;
case FSG_STATE_EXIT:
case FSG_STATE_TERMINATED:
- do_set_config(common, 0); /* Free resources */
+ do_set_interface(common, NULL); /* Free resources */
spin_lock_irq(&common->lock);
common->state = FSG_STATE_TERMINATED; /* Stop the thread */
spin_unlock_irq(&common->lock);
/* Maybe allocate device-global string IDs, and patch descriptors */
if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
rc = usb_string_id(cdev);
- if (rc < 0) {
- kfree(common);
- return ERR_PTR(rc);
- }
+ if (unlikely(rc < 0))
+ goto error_release;
fsg_strings[FSG_STRING_INTERFACE].id = rc;
fsg_intf_desc.iInterface = rc;
}
/* Create the LUNs, open their backing files, and register the
* LUN devices in sysfs. */
curlun = kzalloc(nluns * sizeof *curlun, GFP_KERNEL);
- if (!curlun) {
- kfree(common);
- return ERR_PTR(-ENOMEM);
+ if (unlikely(!curlun)) {
+ rc = -ENOMEM;
+ goto error_release;
}
common->luns = curlun;
/* Data buffers cyclic list */
- /* Buffers in buffhds are static -- no need for additional
- * allocation. */
bh = common->buffhds;
- i = FSG_NUM_BUFFERS - 1;
+ i = FSG_NUM_BUFFERS;
+ goto buffhds_first_it;
do {
bh->next = bh + 1;
- } while (++bh, --i);
+ ++bh;
+buffhds_first_it:
+ bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
+ if (unlikely(!bh->buf)) {
+ rc = -ENOMEM;
+ goto error_release;
+ }
+ } while (--i);
bh->next = common->buffhds;
goto error_release;
}
init_completion(&common->thread_notifier);
+ init_waitqueue_head(&common->fsg_wait);
#undef OR
static void fsg_common_release(struct kref *ref)
{
- struct fsg_common *common =
- container_of(ref, struct fsg_common, ref);
- unsigned i = common->nluns;
- struct fsg_lun *lun = common->luns;
+ struct fsg_common *common = container_of(ref, struct fsg_common, ref);
/* If the thread isn't already dead, tell it to exit now */
if (common->state != FSG_STATE_TERMINATED) {
complete(&common->thread_notifier);
}
- /* Beware tempting for -> do-while optimization: when in error
- * recovery nluns may be zero. */
+ if (likely(common->luns)) {
+ struct fsg_lun *lun = common->luns;
+ unsigned i = common->nluns;
+
+ /* In error recovery common->nluns may be zero. */
+ for (; i; --i, ++lun) {
+ device_remove_file(&lun->dev, &dev_attr_ro);
+ device_remove_file(&lun->dev, &dev_attr_file);
+ fsg_lun_close(lun);
+ device_unregister(&lun->dev);
+ }
+
+ kfree(common->luns);
+ }
- for (; i; --i, ++lun) {
- device_remove_file(&lun->dev, &dev_attr_ro);
- device_remove_file(&lun->dev, &dev_attr_file);
- fsg_lun_close(lun);
- device_unregister(&lun->dev);
+ {
+ struct fsg_buffhd *bh = common->buffhds;
+ unsigned i = FSG_NUM_BUFFERS;
+ do {
+ kfree(bh->buf);
+ } while (++bh, --i);
}
- kfree(common->luns);
if (common->free_storage_on_release)
kfree(common);
}
static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
{
struct fsg_dev *fsg = fsg_from_func(f);
+ struct fsg_common *common = fsg->common;
DBG(fsg, "unbind\n");
- fsg_common_put(fsg->common);
+ if (fsg->common->fsg == fsg) {
+ fsg->common->new_fsg = NULL;
+ raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
+ /* FIXME: make interruptible or killable somehow? */
+ wait_event(common->fsg_wait, common->fsg != fsg);
+ }
+
+ fsg_common_put(common);
+ usb_free_descriptors(fsg->function.descriptors);
+ usb_free_descriptors(fsg->function.hs_descriptors);
kfree(fsg);
}
-static int __init fsg_bind(struct usb_configuration *c, struct usb_function *f)
+static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
{
struct fsg_dev *fsg = fsg_from_func(f);
struct usb_gadget *gadget = c->cdev->gadget;
- int rc;
int i;
struct usb_ep *ep;
ep->driver_data = fsg->common; /* claim the endpoint */
fsg->bulk_out = ep;
+ /* Copy descriptors */
+ f->descriptors = usb_copy_descriptors(fsg_fs_function);
+ if (unlikely(!f->descriptors))
+ return -ENOMEM;
+
if (gadget_is_dualspeed(gadget)) {
/* Assume endpoint addresses are the same for both speeds */
fsg_hs_bulk_in_desc.bEndpointAddress =
fsg_fs_bulk_in_desc.bEndpointAddress;
fsg_hs_bulk_out_desc.bEndpointAddress =
fsg_fs_bulk_out_desc.bEndpointAddress;
- f->hs_descriptors = fsg_hs_function;
+ f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
+ if (unlikely(!f->hs_descriptors)) {
+ usb_free_descriptors(f->descriptors);
+ return -ENOMEM;
+ }
}
return 0;
autoconf_fail:
ERROR(fsg, "unable to autoconfigure all endpoints\n");
- rc = -ENOTSUPP;
- return rc;
+ return -ENOTSUPP;
}
fsg->function.name = FSG_DRIVER_DESC;
fsg->function.strings = fsg_strings_array;
- fsg->function.descriptors = fsg_fs_function;
fsg->function.bind = fsg_bind;
fsg->function.unbind = fsg_unbind;
fsg->function.setup = fsg_setup;
* call to usb_add_function() was successful. */
rc = usb_add_function(c, &fsg->function);
-
- if (likely(rc == 0))
- fsg_common_get(fsg->common);
- else
+ if (unlikely(rc))
kfree(fsg);
-
+ else
+ fsg_common_get(fsg->common);
return rc;
}