diff options
| -rw-r--r-- | drivers/gpu/drm/drm_dp_aux_dev.c | 109 |
1 files changed, 46 insertions, 63 deletions
diff --git a/drivers/gpu/drm/drm_dp_aux_dev.c b/drivers/gpu/drm/drm_dp_aux_dev.c index ec1ed94b2390..d34e5096887a 100644 --- a/drivers/gpu/drm/drm_dp_aux_dev.c +++ b/drivers/gpu/drm/drm_dp_aux_dev.c @@ -32,6 +32,7 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/uaccess.h> +#include <linux/uio.h> #include <drm/drm_dp_helper.h> #include <drm/drm_crtc.h> #include <drm/drmP.h> @@ -140,101 +141,83 @@ static loff_t auxdev_llseek(struct file *file, loff_t offset, int whence) return fixed_size_llseek(file, offset, whence, AUX_MAX_OFFSET); } -static ssize_t auxdev_read(struct file *file, char __user *buf, size_t count, - loff_t *offset) +static ssize_t auxdev_read_iter(struct kiocb *iocb, struct iov_iter *to) { - size_t bytes_pending, num_bytes_processed = 0; - struct drm_dp_aux_dev *aux_dev = file->private_data; + struct drm_dp_aux_dev *aux_dev = iocb->ki_filp->private_data; + loff_t pos = iocb->ki_pos; ssize_t res = 0; if (!atomic_inc_not_zero(&aux_dev->usecount)) return -ENODEV; - bytes_pending = min((loff_t)count, AUX_MAX_OFFSET - (*offset)); - - if (!access_ok(VERIFY_WRITE, buf, bytes_pending)) { - res = -EFAULT; - goto out; - } + iov_iter_truncate(to, AUX_MAX_OFFSET - pos); - while (bytes_pending > 0) { - uint8_t localbuf[DP_AUX_MAX_PAYLOAD_BYTES]; - ssize_t todo = min_t(size_t, bytes_pending, sizeof(localbuf)); + while (iov_iter_count(to)) { + uint8_t buf[DP_AUX_MAX_PAYLOAD_BYTES]; + ssize_t todo = min(iov_iter_count(to), sizeof(buf)); if (signal_pending(current)) { - res = num_bytes_processed ? - num_bytes_processed : -ERESTARTSYS; - goto out; + res = -ERESTARTSYS; + break; } - res = drm_dp_dpcd_read(aux_dev->aux, *offset, localbuf, todo); - if (res <= 0) { - res = num_bytes_processed ? num_bytes_processed : res; - goto out; - } - if (__copy_to_user(buf + num_bytes_processed, localbuf, res)) { - res = num_bytes_processed ? - num_bytes_processed : -EFAULT; - goto out; + res = drm_dp_dpcd_read(aux_dev->aux, pos, buf, todo); + if (res <= 0) + break; + + if (copy_to_iter(buf, res, to) != res) { + res = -EFAULT; + break; } - bytes_pending -= res; - *offset += res; - num_bytes_processed += res; - res = num_bytes_processed; + + pos += res; } -out: + if (pos != iocb->ki_pos) + res = pos - iocb->ki_pos; + iocb->ki_pos = pos; + atomic_dec(&aux_dev->usecount); wake_up_atomic_t(&aux_dev->usecount); return res; } -static ssize_t auxdev_write(struct file *file, const char __user *buf, - size_t count, loff_t *offset) +static ssize_t auxdev_write_iter(struct kiocb *iocb, struct iov_iter *from) { - size_t bytes_pending, num_bytes_processed = 0; - struct drm_dp_aux_dev *aux_dev = file->private_data; + struct drm_dp_aux_dev *aux_dev = iocb->ki_filp->private_data; + loff_t pos = iocb->ki_pos; ssize_t res = 0; if (!atomic_inc_not_zero(&aux_dev->usecount)) return -ENODEV; - bytes_pending = min((loff_t)count, AUX_MAX_OFFSET - *offset); - - if (!access_ok(VERIFY_READ, buf, bytes_pending)) { - res = -EFAULT; - goto out; - } + iov_iter_truncate(from, AUX_MAX_OFFSET - pos); - while (bytes_pending > 0) { - uint8_t localbuf[DP_AUX_MAX_PAYLOAD_BYTES]; - ssize_t todo = min_t(size_t, bytes_pending, sizeof(localbuf)); + while (iov_iter_count(from)) { + uint8_t buf[DP_AUX_MAX_PAYLOAD_BYTES]; + ssize_t todo = min(iov_iter_count(from), sizeof(buf)); if (signal_pending(current)) { - res = num_bytes_processed ? - num_bytes_processed : -ERESTARTSYS; - goto out; + res = -ERESTARTSYS; + break; } - if (__copy_from_user(localbuf, - buf + num_bytes_processed, todo)) { - res = num_bytes_processed ? - num_bytes_processed : -EFAULT; - goto out; + if (!copy_from_iter_full(buf, todo, from)) { + res = -EFAULT; + break; } - res = drm_dp_dpcd_write(aux_dev->aux, *offset, localbuf, todo); - if (res <= 0) { - res = num_bytes_processed ? num_bytes_processed : res; - goto out; - } - bytes_pending -= res; - *offset += res; - num_bytes_processed += res; - res = num_bytes_processed; + res = drm_dp_dpcd_write(aux_dev->aux, pos, buf, todo); + if (res <= 0) + break; + + pos += res; } -out: + if (pos != iocb->ki_pos) + res = pos - iocb->ki_pos; + iocb->ki_pos = pos; + atomic_dec(&aux_dev->usecount); wake_up_atomic_t(&aux_dev->usecount); return res; @@ -251,8 +234,8 @@ static int auxdev_release(struct inode *inode, struct file *file) static const struct file_operations auxdev_fops = { .owner = THIS_MODULE, .llseek = auxdev_llseek, - .read = auxdev_read, - .write = auxdev_write, + .read_iter = auxdev_read_iter, + .write_iter = auxdev_write_iter, .open = auxdev_open, .release = auxdev_release, }; |