Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

infinibad: weird APIs switched to ->write_iter()

Browse source 
Things Not To Do When Writing A Driver, part 1001st:
have writev() and write() on the same file doing completely
different things.  As in, "interpret very different sets of
commands".

	We _can_ handle that, but it's a bloody bad idea.
Don't do that in new drivers.  Ever.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2015-04-04 00:11:32 -04:00
parent 9a219bc70b
commit 4961772560
2 changed files with 23 additions and 15 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

18
drivers/infiniband/hw/ipath/ipath_file_ops.c
View file

@ -42,6 +42,7 @@
#include <linux/io.h>
#include <linux/jiffies.h>
#include <linux/cpu.h>
#include <linux/uio.h>
#include <asm/pgtable.h>
#include "ipath_kernel.h"
@ -52,15 +53,19 @@ static int ipath_open(struct inode *, struct file *);
static int ipath_close(struct inode *, struct file *);
static ssize_t ipath_write(struct file *, const char __user *, size_t,
loff_t *);
static ssize_t ipath_writev(struct kiocb *, const struct iovec *,
unsigned long , loff_t);
static ssize_t ipath_write_iter(struct kiocb *, struct iov_iter *from);
static unsigned int ipath_poll(struct file *, struct poll_table_struct *);
static int ipath_mmap(struct file *, struct vm_area_struct *);
/*
* This is really, really weird shit - write() and writev() here
* have completely unrelated semantics. Sucky userland ABI,
* film at 11.
*/
static const struct file_operations ipath_file_ops = {
.owner = THIS_MODULE,
.write = ipath_write,
.aio_write = ipath_writev,
.write_iter = ipath_write_iter,
.open = ipath_open,
.release = ipath_close,
.poll = ipath_poll,
@ -2413,18 +2418,17 @@ static ssize_t ipath_write(struct file *fp, const char __user *data,
return ret;
}
static ssize_t ipath_writev(struct kiocb *iocb, const struct iovec *iov,
unsigned long dim, loff_t off)
static ssize_t ipath_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
struct file *filp = iocb->ki_filp;
struct ipath_filedata *fp = filp->private_data;
struct ipath_portdata *pd = port_fp(filp);
struct ipath_user_sdma_queue *pq = fp->pq;
if (!dim)
if (!iter_is_iovec(from) || !from->nr_segs)
return -EINVAL;
return ipath_user_sdma_writev(pd->port_dd, pq, iov, dim);
return ipath_user_sdma_writev(pd->port_dd, pq, from->iov, from->nr_segs);
}
static struct class *ipath_class;

20
drivers/infiniband/hw/qib/qib_file_ops.c
View file

@ -43,6 +43,7 @@
#include <asm/pgtable.h>
#include <linux/delay.h>
#include <linux/export.h>
#include <linux/uio.h>
#include "qib.h"
#include "qib_common.h"
@ -54,15 +55,19 @@
static int qib_open(struct inode *, struct file *);
static int qib_close(struct inode *, struct file *);
static ssize_t qib_write(struct file *, const char __user *, size_t, loff_t *);
static ssize_t qib_aio_write(struct kiocb *, const struct iovec *,
unsigned long, loff_t);
static ssize_t qib_write_iter(struct kiocb *, struct iov_iter *);
static unsigned int qib_poll(struct file *, struct poll_table_struct *);
static int qib_mmapf(struct file *, struct vm_area_struct *);
/*
* This is really, really weird shit - write() and writev() here
* have completely unrelated semantics. Sucky userland ABI,
* film at 11.
*/
static const struct file_operations qib_file_ops = {
.owner = THIS_MODULE,
.write = qib_write,
.aio_write = qib_aio_write,
.write_iter = qib_write_iter,
.open = qib_open,
.release = qib_close,
.poll = qib_poll,
@ -2248,17 +2253,16 @@ static ssize_t qib_write(struct file *fp, const char __user *data,
return ret;
}
static ssize_t qib_aio_write(struct kiocb *iocb, const struct iovec *iov,
unsigned long dim, loff_t off)
static ssize_t qib_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
struct qib_filedata *fp = iocb->ki_filp->private_data;
struct qib_ctxtdata *rcd = ctxt_fp(iocb->ki_filp);
struct qib_user_sdma_queue *pq = fp->pq;
if (!dim || !pq)
if (!iter_is_iovec(from) || !from->nr_segs || !pq)
return -EINVAL;
return qib_user_sdma_writev(rcd, pq, iov, dim);
return qib_user_sdma_writev(rcd, pq, from->iov, from->nr_segs);
}
static struct class *qib_class;