diff options
-rw-r--r-- | drivers/char/mem.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 2c644af..e49265f 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -627,6 +627,18 @@ static ssize_t write_null(struct file *file, const char __user *buf, return count; } +static ssize_t aio_read_null(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) +{ + return 0; +} + +static ssize_t aio_write_null(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) +{ + return iov_length(iov, nr_segs); +} + static int pipe_to_null(struct pipe_inode_info *info, struct pipe_buffer *buf, struct splice_desc *sd) { @@ -670,6 +682,24 @@ static ssize_t read_zero(struct file *file, char __user *buf, return written ? written : -EFAULT; } +static ssize_t aio_read_zero(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) +{ + size_t written = 0; + unsigned long i; + ssize_t ret; + + for (i = 0; i < nr_segs; i++) { + ret = read_zero(iocb->ki_filp, iov[i].iov_base, iov[i].iov_len, + &pos); + if (ret < 0) + break; + written += ret; + } + + return written ? written : -EFAULT; +} + static int mmap_zero(struct file *file, struct vm_area_struct *vma) { #ifndef CONFIG_MMU @@ -738,6 +768,7 @@ static int open_port(struct inode *inode, struct file *filp) #define full_lseek null_lseek #define write_zero write_null #define read_full read_zero +#define aio_write_zero aio_write_null #define open_mem open_port #define open_kmem open_mem #define open_oldmem open_mem @@ -766,6 +797,8 @@ static const struct file_operations null_fops = { .llseek = null_lseek, .read = read_null, .write = write_null, + .aio_read = aio_read_null, + .aio_write = aio_write_null, .splice_write = splice_write_null, }; @@ -782,6 +815,8 @@ static const struct file_operations zero_fops = { .llseek = zero_lseek, .read = read_zero, .write = write_zero, + .aio_read = aio_read_zero, + .aio_write = aio_write_zero, .mmap = mmap_zero, }; |