diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/class/cdc-acm.c | 4 | ||||
| -rw-r--r-- | drivers/usb/dwc3/core.c | 5 | ||||
| -rw-r--r-- | drivers/usb/gadget/function/f_fs.c | 107 | ||||
| -rw-r--r-- | drivers/usb/gadget/function/u_ether.c | 8 |
4 files changed, 96 insertions, 28 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 0f3f62e81..3ca9fdb0a 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -946,8 +946,6 @@ static int wait_serial_change(struct acm *acm, unsigned long arg) DECLARE_WAITQUEUE(wait, current); struct async_icount old, new; - if (arg & (TIOCM_DSR | TIOCM_RI | TIOCM_CD)) - return -EINVAL; do { spin_lock_irq(&acm->read_lock); old = acm->oldcount; @@ -1175,6 +1173,8 @@ static int acm_probe(struct usb_interface *intf, if (quirks == IGNORE_DEVICE) return -ENODEV; + memset(&h, 0x00, sizeof(struct usb_cdc_parsed_header)); + num_rx_buf = (quirks == SINGLE_RX_URB) ? 1 : ACM_NR; /* handle quirks deadly to normal probing*/ diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index 35d092456..2d47010e5 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -669,15 +669,14 @@ static int dwc3_core_init(struct dwc3 *dwc) return 0; err4: - phy_power_off(dwc->usb2_generic_phy); + phy_power_off(dwc->usb3_generic_phy); err3: - phy_power_off(dwc->usb3_generic_phy); + phy_power_off(dwc->usb2_generic_phy); err2: usb_phy_set_suspend(dwc->usb2_phy, 1); usb_phy_set_suspend(dwc->usb3_phy, 1); - dwc3_core_exit(dwc); err1: usb_phy_shutdown(dwc->usb2_phy); diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index 5c8429f23..3a5530d05 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -133,8 +133,60 @@ struct ffs_epfile { /* * Buffer for holding data from partial reads which may happen since * we’re rounding user read requests to a multiple of a max packet size. + * + * The pointer is initialised with NULL value and may be set by + * __ffs_epfile_read_data function to point to a temporary buffer. + * + * In normal operation, calls to __ffs_epfile_read_buffered will consume + * data from said buffer and eventually free it. Importantly, while the + * function is using the buffer, it sets the pointer to NULL. This is + * all right since __ffs_epfile_read_data and __ffs_epfile_read_buffered + * can never run concurrently (they are synchronised by epfile->mutex) + * so the latter will not assign a new value to the pointer. + * + * Meanwhile ffs_func_eps_disable frees the buffer (if the pointer is + * valid) and sets the pointer to READ_BUFFER_DROP value. This special + * value is crux of the synchronisation between ffs_func_eps_disable and + * __ffs_epfile_read_data. + * + * Once __ffs_epfile_read_data is about to finish it will try to set the + * pointer back to its old value (as described above), but seeing as the + * pointer is not-NULL (namely READ_BUFFER_DROP) it will instead free + * the buffer. + * + * == State transitions == + * + * • ptr == NULL: (initial state) + * ◦ __ffs_epfile_read_buffer_free: go to ptr == DROP + * ◦ __ffs_epfile_read_buffered: nop + * ◦ __ffs_epfile_read_data allocates temp buffer: go to ptr == buf + * ◦ reading finishes: n/a, not in ‘and reading’ state + * • ptr == DROP: + * ◦ __ffs_epfile_read_buffer_free: nop + * ◦ __ffs_epfile_read_buffered: go to ptr == NULL + * ◦ __ffs_epfile_read_data allocates temp buffer: free buf, nop + * ◦ reading finishes: n/a, not in ‘and reading’ state + * • ptr == buf: + * ◦ __ffs_epfile_read_buffer_free: free buf, go to ptr == DROP + * ◦ __ffs_epfile_read_buffered: go to ptr == NULL and reading + * ◦ __ffs_epfile_read_data: n/a, __ffs_epfile_read_buffered + * is always called first + * ◦ reading finishes: n/a, not in ‘and reading’ state + * • ptr == NULL and reading: + * ◦ __ffs_epfile_read_buffer_free: go to ptr == DROP and reading + * ◦ __ffs_epfile_read_buffered: n/a, mutex is held + * ◦ __ffs_epfile_read_data: n/a, mutex is held + * ◦ reading finishes and … + * … all data read: free buf, go to ptr == NULL + * … otherwise: go to ptr == buf and reading + * • ptr == DROP and reading: + * ◦ __ffs_epfile_read_buffer_free: nop + * ◦ __ffs_epfile_read_buffered: n/a, mutex is held + * ◦ __ffs_epfile_read_data: n/a, mutex is held + * ◦ reading finishes: free buf, go to ptr == DROP */ - struct ffs_buffer *read_buffer; /* P: epfile->mutex */ + struct ffs_buffer *read_buffer; +#define READ_BUFFER_DROP ((struct ffs_buffer *)ERR_PTR(-ESHUTDOWN)) char name[5]; @@ -733,25 +785,47 @@ static void ffs_epfile_async_io_complete(struct usb_ep *_ep, schedule_work(&io_data->work); } +static void __ffs_epfile_read_buffer_free(struct ffs_epfile *epfile) +{ + /* + * See comment in struct ffs_epfile for full read_buffer pointer + * synchronisation story. + */ + struct ffs_buffer *buf = xchg(&epfile->read_buffer, READ_BUFFER_DROP); + if (buf && buf != READ_BUFFER_DROP) + kfree(buf); +} + /* Assumes epfile->mutex is held. */ static ssize_t __ffs_epfile_read_buffered(struct ffs_epfile *epfile, struct iov_iter *iter) { - struct ffs_buffer *buf = epfile->read_buffer; + /* + * Null out epfile->read_buffer so ffs_func_eps_disable does not free + * the buffer while we are using it. See comment in struct ffs_epfile + * for full read_buffer pointer synchronisation story. + */ + struct ffs_buffer *buf = xchg(&epfile->read_buffer, NULL); ssize_t ret; - if (!buf) + if (!buf || buf == READ_BUFFER_DROP) return 0; ret = copy_to_iter(buf->data, buf->length, iter); if (buf->length == ret) { kfree(buf); - epfile->read_buffer = NULL; - } else if (unlikely(iov_iter_count(iter))) { + return ret; + } + + if (unlikely(iov_iter_count(iter))) { ret = -EFAULT; } else { buf->length -= ret; buf->data += ret; } + + if (cmpxchg(&epfile->read_buffer, NULL, buf)) + kfree(buf); + return ret; } @@ -780,7 +854,15 @@ static ssize_t __ffs_epfile_read_data(struct ffs_epfile *epfile, buf->length = data_len; buf->data = buf->storage; memcpy(buf->storage, data + ret, data_len); - epfile->read_buffer = buf; + + /* + * At this point read_buffer is NULL or READ_BUFFER_DROP (if + * ffs_func_eps_disable has been called in the meanwhile). See comment + * in struct ffs_epfile for full read_buffer pointer synchronisation + * story. + */ + if (unlikely(cmpxchg(&epfile->read_buffer, NULL, buf))) + kfree(buf); return ret; } @@ -1094,8 +1176,7 @@ ffs_epfile_release(struct inode *inode, struct file *file) ENTER(); - kfree(epfile->read_buffer); - epfile->read_buffer = NULL; + __ffs_epfile_read_buffer_free(epfile); ffs_data_closed(epfile->ffs); return 0; @@ -1721,24 +1802,20 @@ static void ffs_func_eps_disable(struct ffs_function *func) unsigned count = func->ffs->eps_count; unsigned long flags; + spin_lock_irqsave(&func->ffs->eps_lock, flags); do { - if (epfile) - mutex_lock(&epfile->mutex); - spin_lock_irqsave(&func->ffs->eps_lock, flags); /* pending requests get nuked */ if (likely(ep->ep)) usb_ep_disable(ep->ep); ++ep; - spin_unlock_irqrestore(&func->ffs->eps_lock, flags); if (epfile) { epfile->ep = NULL; - kfree(epfile->read_buffer); - epfile->read_buffer = NULL; - mutex_unlock(&epfile->mutex); + __ffs_epfile_read_buffer_free(epfile); ++epfile; } } while (--count); + spin_unlock_irqrestore(&func->ffs->eps_lock, flags); } static int ffs_func_eps_enable(struct ffs_function *func) diff --git a/drivers/usb/gadget/function/u_ether.c b/drivers/usb/gadget/function/u_ether.c index 9b9e71f2c..f590adaab 100644 --- a/drivers/usb/gadget/function/u_ether.c +++ b/drivers/usb/gadget/function/u_ether.c @@ -585,14 +585,6 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb, req->length = length; - /* throttle high/super speed IRQ rate back slightly */ - if (gadget_is_dualspeed(dev->gadget)) - req->no_interrupt = (((dev->gadget->speed == USB_SPEED_HIGH || - dev->gadget->speed == USB_SPEED_SUPER)) && - !list_empty(&dev->tx_reqs)) - ? ((atomic_read(&dev->tx_qlen) % dev->qmult) != 0) - : 0; - retval = usb_ep_queue(in, req, GFP_ATOMIC); switch (retval) { default: |