summaryrefslogtreecommitdiff
path: root/include/linux/spi/spi.h
diff options
context:
space:
mode:
authorAndy Shevchenko <andriy.shevchenko@linux.intel.com>2023-07-14 12:17:48 +0300
committerMark Brown <broonie@kernel.org>2023-07-14 14:44:39 +0100
commit75e308ffc4f0d36b895f1110ece8b77d4116fdb1 (patch)
tree3c3f612b0c248bcc5740b0376fc6effed9081fe8 /include/linux/spi/spi.h
parent169f5312dc46deb986e368b6828bedbedd297f6e (diff)
spi: Use struct_size() helper
The Documentation/process/deprecated.rst suggests to use flexible array members to provide a way to declare having a dynamically sized set of trailing elements in a structure.This makes code robust agains bunch of the issues described in the documentation, main of which is about the correctness of the sizeof() calculation for this data structure. Due to above, prefer struct_size() over open-coded versions. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20230714091748.89681-5-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'include/linux/spi/spi.h')
-rw-r--r--include/linux/spi/spi.h15
1 files changed, 9 insertions, 6 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 04daf61dfd3f..7f8b478fdeb3 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -13,6 +13,7 @@
#include <linux/gpio/consumer.h>
#include <linux/kthread.h>
#include <linux/mod_devicetable.h>
+#include <linux/overflow.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/u64_stats_sync.h>
@@ -1085,6 +1086,8 @@ struct spi_transfer {
* @state: for use by whichever driver currently owns the message
* @resources: for resource management when the SPI message is processed
* @prepared: spi_prepare_message was called for the this message
+ * @t: for use with spi_message_alloc() when message and transfers have
+ * been allocated together
*
* A @spi_message is used to execute an atomic sequence of data transfers,
* each represented by a struct spi_transfer. The sequence is "atomic"
@@ -1139,6 +1142,9 @@ struct spi_message {
/* List of spi_res resources when the SPI message is processed */
struct list_head resources;
+
+ /* For embedding transfers into the memory of the message */
+ struct spi_transfer t[];
};
static inline void spi_message_init_no_memset(struct spi_message *m)
@@ -1199,16 +1205,13 @@ static inline struct spi_message *spi_message_alloc(unsigned ntrans, gfp_t flags
{
struct spi_message *m;
- m = kzalloc(sizeof(struct spi_message)
- + ntrans * sizeof(struct spi_transfer),
- flags);
+ m = kzalloc(struct_size(m, t, ntrans), flags);
if (m) {
unsigned i;
- struct spi_transfer *t = (struct spi_transfer *)(m + 1);
spi_message_init_no_memset(m);
- for (i = 0; i < ntrans; i++, t++)
- spi_message_add_tail(t, m);
+ for (i = 0; i < ntrans; i++)
+ spi_message_add_tail(&m->t[i], m);
}
return m;
}