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V4L/DVB (8130): split dvb_ringbuffer dual-use functions

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split the suckers into kernel-memory and user-memory versions,
annotate both properly.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
Al Viro
2008-06-22 14:20:29 -03:00
committed by Mauro Carvalho Chehab
parent 67778b3227
commit b0ba0e3ab6
7 changed files with 69 additions and 37 deletions
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78
drivers/media/dvb/dvb-core/dvb_ringbuffer.c
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@@ -107,35 +107,43 @@ void dvb_ringbuffer_flush_spinlock_wakeup(struct dvb_ringbuffer *rbuf)
wake_up(&rbuf->queue);
}
ssize_t dvb_ringbuffer_read(struct dvb_ringbuffer *rbuf, u8 *buf, size_t len, int usermem)
ssize_t dvb_ringbuffer_read_user(struct dvb_ringbuffer *rbuf, u8 __user *buf, size_t len)
{
size_t todo = len;
size_t split;
split = (rbuf->pread + len > rbuf->size) ? rbuf->size - rbuf->pread : 0;
if (split > 0) {
if (!usermem)
memcpy(buf, rbuf->data+rbuf->pread, split);
else
if (copy_to_user(buf, rbuf->data+rbuf->pread, split))
return -EFAULT;
if (copy_to_user(buf, rbuf->data+rbuf->pread, split))
return -EFAULT;
buf += split;
todo -= split;
rbuf->pread = 0;
}
if (!usermem)
memcpy(buf, rbuf->data+rbuf->pread, todo);
else
if (copy_to_user(buf, rbuf->data+rbuf->pread, todo))
return -EFAULT;
if (copy_to_user(buf, rbuf->data+rbuf->pread, todo))
return -EFAULT;
rbuf->pread = (rbuf->pread + todo) % rbuf->size;
return len;
}
void dvb_ringbuffer_read(struct dvb_ringbuffer *rbuf, u8 *buf, size_t len)
{
size_t todo = len;
size_t split;
split = (rbuf->pread + len > rbuf->size) ? rbuf->size - rbuf->pread : 0;
if (split > 0) {
memcpy(buf, rbuf->data+rbuf->pread, split);
buf += split;
todo -= split;
rbuf->pread = 0;
}
memcpy(buf, rbuf->data+rbuf->pread, todo);
rbuf->pread = (rbuf->pread + todo) % rbuf->size;
}
ssize_t dvb_ringbuffer_write(struct dvb_ringbuffer *rbuf, const u8 *buf, size_t len)
@@ -171,8 +179,8 @@ ssize_t dvb_ringbuffer_pkt_write(struct dvb_ringbuffer *rbuf, u8* buf, size_t le
return status;
}
ssize_t dvb_ringbuffer_pkt_read(struct dvb_ringbuffer *rbuf, size_t idx,
int offset, u8* buf, size_t len, int usermem)
ssize_t dvb_ringbuffer_pkt_read_user(struct dvb_ringbuffer *rbuf, size_t idx,
int offset, u8 __user *buf, size_t len)
{
size_t todo;
size_t split;
@@ -187,24 +195,43 @@ ssize_t dvb_ringbuffer_pkt_read(struct dvb_ringbuffer *rbuf, size_t idx,
todo = len;
split = ((idx + len) > rbuf->size) ? rbuf->size - idx : 0;
if (split > 0) {
if (!usermem)
memcpy(buf, rbuf->data+idx, split);
else
if (copy_to_user(buf, rbuf->data+idx, split))
return -EFAULT;
if (copy_to_user(buf, rbuf->data+idx, split))
return -EFAULT;
buf += split;
todo -= split;
idx = 0;
}
if (!usermem)
memcpy(buf, rbuf->data+idx, todo);
else
if (copy_to_user(buf, rbuf->data+idx, todo))
return -EFAULT;
if (copy_to_user(buf, rbuf->data+idx, todo))
return -EFAULT;
return len;
}
ssize_t dvb_ringbuffer_pkt_read(struct dvb_ringbuffer *rbuf, size_t idx,
int offset, u8* buf, size_t len)
{
size_t todo;
size_t split;
size_t pktlen;
pktlen = rbuf->data[idx] << 8;
pktlen |= rbuf->data[(idx + 1) % rbuf->size];
if (offset > pktlen) return -EINVAL;
if ((offset + len) > pktlen) len = pktlen - offset;
idx = (idx + DVB_RINGBUFFER_PKTHDRSIZE + offset) % rbuf->size;
todo = len;
split = ((idx + len) > rbuf->size) ? rbuf->size - idx : 0;
if (split > 0) {
memcpy(buf, rbuf->data+idx, split);
buf += split;
todo -= split;
idx = 0;
}
memcpy(buf, rbuf->data+idx, todo);
return len;
}
void dvb_ringbuffer_pkt_dispose(struct dvb_ringbuffer *rbuf, size_t idx)
{
size_t pktlen;
@@ -266,5 +293,6 @@ EXPORT_SYMBOL(dvb_ringbuffer_empty);
EXPORT_SYMBOL(dvb_ringbuffer_free);
EXPORT_SYMBOL(dvb_ringbuffer_avail);
EXPORT_SYMBOL(dvb_ringbuffer_flush_spinlock_wakeup);
EXPORT_SYMBOL(dvb_ringbuffer_read_user);
EXPORT_SYMBOL(dvb_ringbuffer_read);
EXPORT_SYMBOL(dvb_ringbuffer_write);