diff options
Diffstat (limited to 'drivers/usb/class/cdc-wdm.c')
| -rw-r--r-- | drivers/usb/class/cdc-wdm.c | 59 |
1 files changed, 38 insertions, 21 deletions
diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c index 1c50baff7725..d2b3cffca3f7 100644 --- a/drivers/usb/class/cdc-wdm.c +++ b/drivers/usb/class/cdc-wdm.c @@ -57,6 +57,8 @@ MODULE_DEVICE_TABLE (usb, wdm_ids); #define WDM_MAX 16 +/* CDC-WMC r1.1 requires wMaxCommand to be "at least 256 decimal (0x100)" */ +#define WDM_DEFAULT_BUFSIZE 256 static DEFINE_MUTEX(wdm_mutex); @@ -88,7 +90,8 @@ struct wdm_device { int count; dma_addr_t shandle; dma_addr_t ihandle; - struct mutex lock; + struct mutex wlock; + struct mutex rlock; wait_queue_head_t wait; struct work_struct rxwork; int werr; @@ -323,7 +326,7 @@ static ssize_t wdm_write } /* concurrent writes and disconnect */ - r = mutex_lock_interruptible(&desc->lock); + r = mutex_lock_interruptible(&desc->wlock); rv = -ERESTARTSYS; if (r) { kfree(buf); @@ -386,7 +389,7 @@ static ssize_t wdm_write out: usb_autopm_put_interface(desc->intf); outnp: - mutex_unlock(&desc->lock); + mutex_unlock(&desc->wlock); outnl: return rv < 0 ? rv : count; } @@ -399,7 +402,7 @@ static ssize_t wdm_read struct wdm_device *desc = file->private_data; - rv = mutex_lock_interruptible(&desc->lock); /*concurrent reads */ + rv = mutex_lock_interruptible(&desc->rlock); /*concurrent reads */ if (rv < 0) return -ERESTARTSYS; @@ -467,14 +470,16 @@ retry: for (i = 0; i < desc->length - cntr; i++) desc->ubuf[i] = desc->ubuf[i + cntr]; + spin_lock_irq(&desc->iuspin); desc->length -= cntr; + spin_unlock_irq(&desc->iuspin); /* in case we had outstanding data */ if (!desc->length) clear_bit(WDM_READ, &desc->flags); rv = cntr; err: - mutex_unlock(&desc->lock); + mutex_unlock(&desc->rlock); return rv; } @@ -540,7 +545,8 @@ static int wdm_open(struct inode *inode, struct file *file) } intf->needs_remote_wakeup = 1; - mutex_lock(&desc->lock); + /* using write lock to protect desc->count */ + mutex_lock(&desc->wlock); if (!desc->count++) { desc->werr = 0; desc->rerr = 0; @@ -553,7 +559,7 @@ static int wdm_open(struct inode *inode, struct file *file) } else { rv = 0; } - mutex_unlock(&desc->lock); + mutex_unlock(&desc->wlock); usb_autopm_put_interface(desc->intf); out: mutex_unlock(&wdm_mutex); @@ -565,9 +571,11 @@ static int wdm_release(struct inode *inode, struct file *file) struct wdm_device *desc = file->private_data; mutex_lock(&wdm_mutex); - mutex_lock(&desc->lock); + + /* using write lock to protect desc->count */ + mutex_lock(&desc->wlock); desc->count--; - mutex_unlock(&desc->lock); + mutex_unlock(&desc->wlock); if (!desc->count) { dev_dbg(&desc->intf->dev, "wdm_release: cleanup"); @@ -630,7 +638,7 @@ static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id) struct usb_cdc_dmm_desc *dmhd; u8 *buffer = intf->altsetting->extra; int buflen = intf->altsetting->extralen; - u16 maxcom = 0; + u16 maxcom = WDM_DEFAULT_BUFSIZE; if (!buffer) goto out; @@ -665,7 +673,8 @@ next_desc: desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL); if (!desc) goto out; - mutex_init(&desc->lock); + mutex_init(&desc->rlock); + mutex_init(&desc->wlock); spin_lock_init(&desc->iuspin); init_waitqueue_head(&desc->wait); desc->wMaxCommand = maxcom; @@ -716,7 +725,7 @@ next_desc: goto err; desc->inbuf = usb_alloc_coherent(interface_to_usbdev(intf), - desc->bMaxPacketSize0, + desc->wMaxCommand, GFP_KERNEL, &desc->response->transfer_dma); if (!desc->inbuf) @@ -779,11 +788,13 @@ static void wdm_disconnect(struct usb_interface *intf) /* to terminate pending flushes */ clear_bit(WDM_IN_USE, &desc->flags); spin_unlock_irqrestore(&desc->iuspin, flags); - mutex_lock(&desc->lock); + wake_up_all(&desc->wait); + mutex_lock(&desc->rlock); + mutex_lock(&desc->wlock); kill_urbs(desc); cancel_work_sync(&desc->rxwork); - mutex_unlock(&desc->lock); - wake_up_all(&desc->wait); + mutex_unlock(&desc->wlock); + mutex_unlock(&desc->rlock); if (!desc->count) cleanup(desc); mutex_unlock(&wdm_mutex); @@ -798,8 +809,10 @@ static int wdm_suspend(struct usb_interface *intf, pm_message_t message) dev_dbg(&desc->intf->dev, "wdm%d_suspend\n", intf->minor); /* if this is an autosuspend the caller does the locking */ - if (!PMSG_IS_AUTO(message)) - mutex_lock(&desc->lock); + if (!PMSG_IS_AUTO(message)) { + mutex_lock(&desc->rlock); + mutex_lock(&desc->wlock); + } spin_lock_irq(&desc->iuspin); if (PMSG_IS_AUTO(message) && @@ -815,8 +828,10 @@ static int wdm_suspend(struct usb_interface *intf, pm_message_t message) kill_urbs(desc); cancel_work_sync(&desc->rxwork); } - if (!PMSG_IS_AUTO(message)) - mutex_unlock(&desc->lock); + if (!PMSG_IS_AUTO(message)) { + mutex_unlock(&desc->wlock); + mutex_unlock(&desc->rlock); + } return rv; } @@ -854,7 +869,8 @@ static int wdm_pre_reset(struct usb_interface *intf) { struct wdm_device *desc = usb_get_intfdata(intf); - mutex_lock(&desc->lock); + mutex_lock(&desc->rlock); + mutex_lock(&desc->wlock); kill_urbs(desc); /* @@ -876,7 +892,8 @@ static int wdm_post_reset(struct usb_interface *intf) int rv; rv = recover_from_urb_loss(desc); - mutex_unlock(&desc->lock); + mutex_unlock(&desc->wlock); + mutex_unlock(&desc->rlock); return 0; } |