diff options
| author | Michal Nazarewicz <mina86@mina86.com> | 2013-12-10 00:55:37 +0100 |
|---|---|---|
| committer | Felipe Balbi <balbi@ti.com> | 2013-12-10 05:44:07 +0100 |
| commit | 219580e64f035bb9018dbb08d340f90b0ac50f8c (patch) | |
| tree | 01861bc2d3b1ab44d02fede789b041837f6ba0c5 /drivers | |
| parent | usb: gadget: f_fs: remove loop from I/O function (diff) | |
| download | linux-219580e64f035bb9018dbb08d340f90b0ac50f8c.tar.xz linux-219580e64f035bb9018dbb08d340f90b0ac50f8c.zip | |
usb: f_fs: check quirk to pad epout buf size when not aligned to maxpacketsize
Check gadget.quirk_ep_out_aligned_size to decide if buffer size requires
to be aligned to maxpacketsize of an out endpoint. ffs_epfile_io() needs
to pad epout buffer to match above condition if quirk is found.
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: David Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/usb/gadget/f_fs.c | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/drivers/usb/gadget/f_fs.c b/drivers/usb/gadget/f_fs.c index 1222cf9b62d3..34940439bb18 100644 --- a/drivers/usb/gadget/f_fs.c +++ b/drivers/usb/gadget/f_fs.c @@ -753,9 +753,10 @@ static ssize_t ffs_epfile_io(struct file *file, char __user *buf, size_t len, int read) { struct ffs_epfile *epfile = file->private_data; + struct usb_gadget *gadget = epfile->ffs->gadget; struct ffs_ep *ep; char *data = NULL; - ssize_t ret; + ssize_t ret, data_len; int halt; /* Are we still active? */ @@ -788,7 +789,13 @@ static ssize_t ffs_epfile_io(struct file *file, /* Allocate & copy */ if (!halt) { - data = kmalloc(len, GFP_KERNEL); + /* + * Controller may require buffer size to be aligned to + * maxpacketsize of an out endpoint. + */ + data_len = read ? usb_ep_align_maybe(gadget, ep->ep, len) : len; + + data = kmalloc(data_len, GFP_KERNEL); if (unlikely(!data)) return -ENOMEM; @@ -823,7 +830,7 @@ static ssize_t ffs_epfile_io(struct file *file, req->context = &done; req->complete = ffs_epfile_io_complete; req->buf = data; - req->length = len; + req->length = data_len; ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC); @@ -835,9 +842,17 @@ static ssize_t ffs_epfile_io(struct file *file, ret = -EINTR; usb_ep_dequeue(ep->ep, req); } else { + /* + * XXX We may end up silently droping data here. + * Since data_len (i.e. req->length) may be bigger + * than len (after being rounded up to maxpacketsize), + * we may end up with more data then user space has + * space for. + */ ret = ep->status; if (read && ret > 0 && - unlikely(copy_to_user(buf, data, ret))) + unlikely(copy_to_user(buf, data, + min_t(size_t, ret, len)))) ret = -EFAULT; } } |