diff options
| -rw-r--r-- | drivers/usb/gadget/function/f_fs.c | 30 |
1 files changed, 27 insertions, 3 deletions
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index 59c69db43041..a429ee374921 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -948,10 +948,34 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data) data_len = usb_ep_align_maybe(gadget, ep->ep, data_len); spin_unlock_irq(&epfile->ffs->eps_lock); - data = kmalloc(data_len, GFP_KERNEL); +retry_malloc: + data = kmalloc(data_len, GFP_KERNEL | __GFP_NOWARN); if (unlikely(!data)) { - ret = -ENOMEM; - goto error_mutex; + /* + * f_fs daemons usually use large size buffer for + * performance. However, this can cause failure of + * kmalloc() due to buddy fragmentation, even if there + * is available memory and thus it can be compacted by + * by kswapd. Therefore, instead of just returning error + * to daemon in the case of failure of kmalloc(), give + * the second chance to allocate buffer with a half size + * until it really fails due to memory shortage. + */ + if (unlikely(data_len <= PAGE_SIZE)) { + ret = -ENOMEM; + goto error_mutex; + } + + data_len = data_len >> 1; + + if (io_data->read) { + spin_lock_irq(&epfile->ffs->eps_lock); + data_len = usb_ep_align_maybe(gadget, + ep->ep, data_len); + spin_unlock_irq(&epfile->ffs->eps_lock); + } + + goto retry_malloc; } if (!io_data->read && copy_from_iter(data, data_len, &io_data->data) != data_len) { |