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path: root/drivers/usb/gadget/file_storage.c
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Diffstat (limited to 'drivers/usb/gadget/file_storage.c')
-rw-r--r--drivers/usb/gadget/file_storage.c93
1 files changed, 57 insertions, 36 deletions
diff --git a/drivers/usb/gadget/file_storage.c b/drivers/usb/gadget/file_storage.c
index ea09aaa3cab..0cea9782d7d 100644
--- a/drivers/usb/gadget/file_storage.c
+++ b/drivers/usb/gadget/file_storage.c
@@ -224,6 +224,7 @@
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/kernel.h>
+#include <linux/kref.h>
#include <linux/kthread.h>
#include <linux/limits.h>
#include <linux/list.h>
@@ -238,7 +239,6 @@
#include <linux/string.h>
#include <linux/suspend.h>
#include <linux/utsname.h>
-#include <linux/wait.h>
#include <linux/usb_ch9.h>
#include <linux/usb_gadget.h>
@@ -250,7 +250,7 @@
#define DRIVER_DESC "File-backed Storage Gadget"
#define DRIVER_NAME "g_file_storage"
-#define DRIVER_VERSION "20 October 2004"
+#define DRIVER_VERSION "28 November 2005"
static const char longname[] = DRIVER_DESC;
static const char shortname[] = DRIVER_NAME;
@@ -335,8 +335,8 @@ MODULE_LICENSE("Dual BSD/GPL");
#define MAX_LUNS 8
/* Arggh! There should be a module_param_array_named macro! */
-static char *file[MAX_LUNS] = {NULL, };
-static int ro[MAX_LUNS] = {0, };
+static char *file[MAX_LUNS];
+static int ro[MAX_LUNS];
static struct {
int num_filenames;
@@ -587,7 +587,7 @@ enum fsg_buffer_state {
struct fsg_buffhd {
void *buf;
dma_addr_t dma;
- volatile enum fsg_buffer_state state;
+ enum fsg_buffer_state state;
struct fsg_buffhd *next;
/* The NetChip 2280 is faster, and handles some protocol faults
@@ -596,9 +596,9 @@ struct fsg_buffhd {
unsigned int bulk_out_intended_length;
struct usb_request *inreq;
- volatile int inreq_busy;
+ int inreq_busy;
struct usb_request *outreq;
- volatile int outreq_busy;
+ int outreq_busy;
};
enum fsg_state {
@@ -631,13 +631,16 @@ struct fsg_dev {
/* filesem protects: backing files in use */
struct rw_semaphore filesem;
+ /* reference counting: wait until all LUNs are released */
+ struct kref ref;
+
struct usb_ep *ep0; // Handy copy of gadget->ep0
struct usb_request *ep0req; // For control responses
- volatile unsigned int ep0_req_tag;
+ unsigned int ep0_req_tag;
const char *ep0req_name;
struct usb_request *intreq; // For interrupt responses
- volatile int intreq_busy;
+ int intreq_busy;
struct fsg_buffhd *intr_buffhd;
unsigned int bulk_out_maxpacket;
@@ -667,7 +670,6 @@ struct fsg_dev {
struct fsg_buffhd *next_buffhd_to_drain;
struct fsg_buffhd buffhds[NUM_BUFFERS];
- wait_queue_head_t thread_wqh;
int thread_wakeup_needed;
struct completion thread_notifier;
struct task_struct *thread_task;
@@ -694,7 +696,6 @@ struct fsg_dev {
unsigned int nluns;
struct lun *luns;
struct lun *curlun;
- struct completion lun_released;
};
typedef void (*fsg_routine_t)(struct fsg_dev *);
@@ -1073,11 +1074,13 @@ static int populate_config_buf(struct usb_gadget *gadget,
/* These routines may be called in process context or in_irq */
+/* Caller must hold fsg->lock */
static void wakeup_thread(struct fsg_dev *fsg)
{
/* Tell the main thread that something has happened */
fsg->thread_wakeup_needed = 1;
- wake_up_all(&fsg->thread_wqh);
+ if (fsg->thread_task)
+ wake_up_process(fsg->thread_task);
}
@@ -1164,11 +1167,12 @@ static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
usb_ep_fifo_flush(ep);
/* Hold the lock while we update the request and buffer states */
+ smp_wmb();
spin_lock(&fsg->lock);
bh->inreq_busy = 0;
bh->state = BUF_STATE_EMPTY;
- spin_unlock(&fsg->lock);
wakeup_thread(fsg);
+ spin_unlock(&fsg->lock);
}
static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
@@ -1185,11 +1189,12 @@ static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
usb_ep_fifo_flush(ep);
/* Hold the lock while we update the request and buffer states */
+ smp_wmb();
spin_lock(&fsg->lock);
bh->outreq_busy = 0;
bh->state = BUF_STATE_FULL;
- spin_unlock(&fsg->lock);
wakeup_thread(fsg);
+ spin_unlock(&fsg->lock);
}
@@ -1206,11 +1211,12 @@ static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
usb_ep_fifo_flush(ep);
/* Hold the lock while we update the request and buffer states */
+ smp_wmb();
spin_lock(&fsg->lock);
fsg->intreq_busy = 0;
bh->state = BUF_STATE_EMPTY;
- spin_unlock(&fsg->lock);
wakeup_thread(fsg);
+ spin_unlock(&fsg->lock);
}
#else
@@ -1261,8 +1267,8 @@ static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
fsg->cbbuf_cmnd_size = req->actual;
memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size);
- spin_unlock(&fsg->lock);
wakeup_thread(fsg);
+ spin_unlock(&fsg->lock);
}
#else
@@ -1514,8 +1520,8 @@ static int fsg_setup(struct usb_gadget *gadget,
/* Use this for bulk or interrupt transfers, not ep0 */
static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
- struct usb_request *req, volatile int *pbusy,
- volatile enum fsg_buffer_state *state)
+ struct usb_request *req, int *pbusy,
+ enum fsg_buffer_state *state)
{
int rc;
@@ -1523,8 +1529,11 @@ static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
dump_msg(fsg, "bulk-in", req->buf, req->length);
else if (ep == fsg->intr_in)
dump_msg(fsg, "intr-in", req->buf, req->length);
+
+ spin_lock_irq(&fsg->lock);
*pbusy = 1;
*state = BUF_STATE_BUSY;
+ spin_unlock_irq(&fsg->lock);
rc = usb_ep_queue(ep, req, GFP_KERNEL);
if (rc != 0) {
*pbusy = 0;
@@ -1544,14 +1553,23 @@ static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
static int sleep_thread(struct fsg_dev *fsg)
{
- int rc;
+ int rc = 0;
/* Wait until a signal arrives or we are woken up */
- rc = wait_event_interruptible(fsg->thread_wqh,
- fsg->thread_wakeup_needed);
+ for (;;) {
+ try_to_freeze();
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (signal_pending(current)) {
+ rc = -EINTR;
+ break;
+ }
+ if (fsg->thread_wakeup_needed)
+ break;
+ schedule();
+ }
+ __set_current_state(TASK_RUNNING);
fsg->thread_wakeup_needed = 0;
- try_to_freeze();
- return (rc ? -EINTR : 0);
+ return rc;
}
@@ -1788,6 +1806,7 @@ static int do_write(struct fsg_dev *fsg)
if (bh->state == BUF_STATE_EMPTY && !get_some_more)
break; // We stopped early
if (bh->state == BUF_STATE_FULL) {
+ smp_rmb();
fsg->next_buffhd_to_drain = bh->next;
bh->state = BUF_STATE_EMPTY;
@@ -2356,6 +2375,7 @@ static int throw_away_data(struct fsg_dev *fsg)
/* Throw away the data in a filled buffer */
if (bh->state == BUF_STATE_FULL) {
+ smp_rmb();
bh->state = BUF_STATE_EMPTY;
fsg->next_buffhd_to_drain = bh->next;
@@ -3021,6 +3041,7 @@ static int get_next_command(struct fsg_dev *fsg)
if ((rc = sleep_thread(fsg)) != 0)
return rc;
}
+ smp_rmb();
rc = received_cbw(fsg, bh);
bh->state = BUF_STATE_EMPTY;
@@ -3642,11 +3663,19 @@ static DEVICE_ATTR(file, 0444, show_file, NULL);
/*-------------------------------------------------------------------------*/
+static void fsg_release(struct kref *ref)
+{
+ struct fsg_dev *fsg = container_of(ref, struct fsg_dev, ref);
+
+ kfree(fsg->luns);
+ kfree(fsg);
+}
+
static void lun_release(struct device *dev)
{
struct fsg_dev *fsg = (struct fsg_dev *) dev_get_drvdata(dev);
- complete(&fsg->lun_released);
+ kref_put(&fsg->ref, fsg_release);
}
static void fsg_unbind(struct usb_gadget *gadget)
@@ -3660,14 +3689,12 @@ static void fsg_unbind(struct usb_gadget *gadget)
clear_bit(REGISTERED, &fsg->atomic_bitflags);
/* Unregister the sysfs attribute files and the LUNs */
- init_completion(&fsg->lun_released);
for (i = 0; i < fsg->nluns; ++i) {
curlun = &fsg->luns[i];
if (curlun->registered) {
device_remove_file(&curlun->dev, &dev_attr_ro);
device_remove_file(&curlun->dev, &dev_attr_file);
device_unregister(&curlun->dev);
- wait_for_completion(&fsg->lun_released);
curlun->registered = 0;
}
}
@@ -3846,6 +3873,7 @@ static int __init fsg_bind(struct usb_gadget *gadget)
curlun->dev.release = lun_release;
device_create_file(&curlun->dev, &dev_attr_ro);
device_create_file(&curlun->dev, &dev_attr_file);
+ kref_get(&fsg->ref);
}
if (file[i] && *file[i]) {
@@ -4061,7 +4089,7 @@ static int __init fsg_alloc(void)
return -ENOMEM;
spin_lock_init(&fsg->lock);
init_rwsem(&fsg->filesem);
- init_waitqueue_head(&fsg->thread_wqh);
+ kref_init(&fsg->ref);
init_completion(&fsg->thread_notifier);
the_fsg = fsg;
@@ -4069,13 +4097,6 @@ static int __init fsg_alloc(void)
}
-static void fsg_free(struct fsg_dev *fsg)
-{
- kfree(fsg->luns);
- kfree(fsg);
-}
-
-
static int __init fsg_init(void)
{
int rc;
@@ -4085,7 +4106,7 @@ static int __init fsg_init(void)
return rc;
fsg = the_fsg;
if ((rc = usb_gadget_register_driver(&fsg_driver)) != 0)
- fsg_free(fsg);
+ kref_put(&fsg->ref, fsg_release);
return rc;
}
module_init(fsg_init);
@@ -4103,6 +4124,6 @@ static void __exit fsg_cleanup(void)
wait_for_completion(&fsg->thread_notifier);
close_all_backing_files(fsg);
- fsg_free(fsg);
+ kref_put(&fsg->ref, fsg_release);
}
module_exit(fsg_cleanup);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-27 21:59:23 +0000