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Merge branch 'work-next' into staging-next

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This commit is contained in:
Greg Kroah-Hartman 2011-12-08 12:16:43 -08:00
commit 19324328ad
2 changed files with 24 additions and 36 deletions
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58
drivers/staging/iio/ring_sw.c
View file

@ -170,6 +170,7 @@ static int iio_read_first_n_sw_rb(struct iio_buffer *r,
u8 *initial_read_p, *initial_write_p, *current_read_p, *end_read_p;
u8 *data;
int ret, max_copied, bytes_to_rip, dead_offset;
size_t data_available, buffer_size;
/* A userspace program has probably made an error if it tries to
* read something that is not a whole number of bpds.
@ -182,9 +183,11 @@ static int iio_read_first_n_sw_rb(struct iio_buffer *r,
n, ring->buf.bytes_per_datum);
goto error_ret;
}
buffer_size = ring->buf.bytes_per_datum*ring->buf.length;
/* Limit size to whole of ring buffer */
bytes_to_rip = min((size_t)(ring->buf.bytes_per_datum*ring->buf.length),
n);
bytes_to_rip = min_t(size_t, buffer_size, n);
data = kmalloc(bytes_to_rip, GFP_KERNEL);
if (data == NULL) {
@ -213,38 +216,24 @@ static int iio_read_first_n_sw_rb(struct iio_buffer *r,
goto error_free_data_cpy;
}
if (initial_write_p >= initial_read_p + bytes_to_rip) {
/* write_p is greater than necessary, all is easy */
max_copied = bytes_to_rip;
if (initial_write_p >= initial_read_p)
data_available = initial_write_p - initial_read_p;
else
data_available = buffer_size - (initial_read_p - initial_write_p);
if (data_available < bytes_to_rip)
bytes_to_rip = data_available;
if (initial_read_p + bytes_to_rip >= ring->data + buffer_size) {
max_copied = ring->data + buffer_size - initial_read_p;
memcpy(data, initial_read_p, max_copied);
end_read_p = initial_read_p + max_copied;
} else if (initial_write_p > initial_read_p) {
/*not enough data to cpy */
max_copied = initial_write_p - initial_read_p;
memcpy(data, initial_read_p, max_copied);
end_read_p = initial_write_p;
memcpy(data + max_copied, ring->data, bytes_to_rip - max_copied);
end_read_p = ring->data + bytes_to_rip - max_copied;
} else {
/* going through 'end' of ring buffer */
max_copied = ring->data
+ ring->buf.length*ring->buf.bytes_per_datum - initial_read_p;
memcpy(data, initial_read_p, max_copied);
/* possible we are done if we align precisely with end */
if (max_copied == bytes_to_rip)
end_read_p = ring->data;
else if (initial_write_p
> ring->data + bytes_to_rip - max_copied) {
/* enough data to finish */
memcpy(data + max_copied, ring->data,
bytes_to_rip - max_copied);
max_copied = bytes_to_rip;
end_read_p = ring->data + (bytes_to_rip - max_copied);
} else { /* not enough data */
memcpy(data + max_copied, ring->data,
initial_write_p - ring->data);
max_copied += initial_write_p - ring->data;
end_read_p = initial_write_p;
}
memcpy(data, initial_read_p, bytes_to_rip);
end_read_p = initial_read_p + bytes_to_rip;
}
/* Now to verify which section was cleanly copied - i.e. how far
* read pointer has been pushed */
current_read_p = ring->read_p;
@ -252,15 +241,14 @@ static int iio_read_first_n_sw_rb(struct iio_buffer *r,
if (initial_read_p <= current_read_p)
dead_offset = current_read_p - initial_read_p;
else
dead_offset = ring->buf.length*ring->buf.bytes_per_datum
- (initial_read_p - current_read_p);
dead_offset = buffer_size - (initial_read_p - current_read_p);
/* possible issue if the initial write has been lapped or indeed
* the point we were reading to has been passed */
/* No valid data read.
* In this case the read pointer is already correct having been
* pushed further than we would look. */
if (max_copied - dead_offset < 0) {
if (bytes_to_rip - dead_offset < 0) {
ret = 0;
goto error_free_data_cpy;
}
@ -276,7 +264,7 @@ static int iio_read_first_n_sw_rb(struct iio_buffer *r,
while (ring->read_p != end_read_p)
ring->read_p = end_read_p;
ret = max_copied - dead_offset;
ret = bytes_to_rip - dead_offset;
if (copy_to_user(buf, data + dead_offset, ret)) {
ret = -EFAULT;

2
drivers/staging/iio/types.h
View file

@ -35,7 +35,7 @@ enum iio_modifier {
IIO_MOD_Y,
IIO_MOD_Z,
IIO_MOD_X_AND_Y,
IIO_MOD_X_ANX_Z,
IIO_MOD_X_AND_Z,
IIO_MOD_Y_AND_Z,
IIO_MOD_X_AND_Y_AND_Z,
IIO_MOD_X_OR_Y,