static int scullc_defer_op(int write, struct kiocb *iocb, const struct iovec * iov, unsigned long count, loff_t pos)
{
struct async_work *stuff;
int result = 0;
/* Copy now while we can access the buffer */
if (write)
{
result = scullc_write(iocb->ki_filp, iov->iov_base, iov->iov_len, &pos);
} else
{
result = scullc_read(iocb->ki_filp, iov->iov_base, iov->iov_len, &pos);
}
/* If this is a synchronous IOCB, we return our status now. */
if (is_sync_kiocb(iocb))
return result;
/* Otherwise defer the completion for a few milliseconds. */
stuff = kmalloc (sizeof (*stuff), GFP_KERNEL);
if (stuff == NULL)
return result; /* No memory, just complete now */
stuff->iocb = iocb;
stuff->result = result;
INIT_DELAYED_WORK(&stuff->dwork, scullc_do_deferred_op);
schedule_delayed_work(&stuff->dwork, HZ/100);
return -EIOCBQUEUED;
}
static int scullc_defer_op(int write, struct kiocb *iocb, char __user *buf,
size_t count, loff_t pos)
{
struct async_work *stuff;
int result;
/* Copy now while we can access the buffer */
if (write)
result = scullc_write(iocb->ki_filp, buf, count, &pos);
else
result = scullc_read(iocb->ki_filp, buf, count, &pos);
/* If this is a synchronous IOCB, we return our status now. */
if (is_sync_kiocb(iocb))
return result;
/* Otherwise defer the completion for a few milliseconds. */
stuff = kmalloc (sizeof (*stuff), GFP_KERNEL);
if (stuff == NULL)
return result; /* No memory, just complete now */
stuff->iocb = iocb;
stuff->result = result;
__INIT_WORK(&stuff->work, scullc_do_deferred_op, stuff);
schedule_delayed_work(&stuff->work, HZ/100);
return -EIOCBQUEUED;
}
static ssize_t
ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos)
{
struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode;
int unaligned_aio = 0;
int ret;
trace_ext4_file_write(iocb->ki_filp->f_path.dentry, iocb->ki_left);
/*
* If we have encountered a bitmap-format file, the size limit
* is smaller than s_maxbytes, which is for extent-mapped files.
*/
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
size_t length = iov_length(iov, nr_segs);
if ((pos > sbi->s_bitmap_maxbytes ||
(pos == sbi->s_bitmap_maxbytes && length > 0)))
return -EFBIG;
if (pos + length > sbi->s_bitmap_maxbytes) {
nr_segs = iov_shorten((struct iovec *)iov, nr_segs,
sbi->s_bitmap_maxbytes - pos);
}
} else if (unlikely((iocb->ki_filp->f_flags & O_DIRECT) &&
!is_sync_kiocb(iocb))) {
unaligned_aio = ext4_unaligned_aio(inode, iov, nr_segs, pos);
}
/* Unaligned direct AIO must be serialized; see comment above */
if (unaligned_aio) {
static unsigned long unaligned_warn_time;
/* Warn about this once per day */
if (printk_timed_ratelimit(&unaligned_warn_time, 60*60*24*HZ))
ext4_msg(inode->i_sb, KERN_WARNING,
"Unaligned AIO/DIO on inode %ld by %s; "
"performance will be poor.",
inode->i_ino, current->comm);
mutex_lock(ext4_aio_mutex(inode));
ext4_aiodio_wait(inode);
}
ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
if (unaligned_aio)
mutex_unlock(ext4_aio_mutex(inode));
trace_file_write_done(iocb->ki_filp);
return ret;
}
static ssize_t
ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos)
{
struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode;
int unaligned_aio = 0;
int ret;
trace_ext4_file_write(iocb->ki_filp->f_path.dentry, iocb->ki_left);
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
size_t length = iov_length(iov, nr_segs);
if ((pos > sbi->s_bitmap_maxbytes ||
(pos == sbi->s_bitmap_maxbytes && length > 0)))
return -EFBIG;
if (pos + length > sbi->s_bitmap_maxbytes) {
nr_segs = iov_shorten((struct iovec *)iov, nr_segs,
sbi->s_bitmap_maxbytes - pos);
}
} else if (unlikely((iocb->ki_filp->f_flags & O_DIRECT) &&
!is_sync_kiocb(iocb))) {
unaligned_aio = ext4_unaligned_aio(inode, iov, nr_segs, pos);
}
if (unaligned_aio) {
static unsigned long unaligned_warn_time;
if (printk_timed_ratelimit(&unaligned_warn_time, 60*60*24*HZ))
ext4_msg(inode->i_sb, KERN_WARNING,
"Unaligned AIO/DIO on inode %ld by %s; "
"performance will be poor.",
inode->i_ino, current->comm);
mutex_lock(ext4_aio_mutex(inode));
ext4_aiodio_wait(inode);
}
ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
if (unaligned_aio)
mutex_unlock(ext4_aio_mutex(inode));
return ret;
}
