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27 March 2024, 02:37:15 UTC
Revision c6ef7fd40eddad38a8825cbd6bb2ce8bdbba88f5 authored by Paul Gortmaker on 04 January 2017, 20:08:15 UTC, committed by Alex Williamson on 04 January 2017, 20:22:38 UTC 
vfio-mdev: fix non-standard ioctl return val causing i386 build fail
 
What appears to be a copy and paste error from the line above gets
the ioctl a ssize_t return value instead of the traditional "int".

The associated sample code used "long" which meant it would compile
for x86-64 but not i386, with the latter failing as follows:

  CC [M]  samples/vfio-mdev/mtty.o
samples/vfio-mdev/mtty.c:1418:20: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
  .ioctl          = mtty_ioctl,
                    ^
samples/vfio-mdev/mtty.c:1418:20: note: (near initialization for ‘mdev_fops.ioctl’)
cc1: some warnings being treated as errors

Since in this case, vfio is working with struct file_operations; as such:

    long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
    long (*compat_ioctl) (struct file *, unsigned int, unsigned long);

...and so here we just standardize on long vs. the normal int that user
space typically sees and documents as per "man ioctl" and similar.

Fixes: 9d1a546c53b4 ("docs: Sample driver to demonstrate how to use Mediated device framework.")
Cc: Kirti Wankhede <kwankhede@nvidia.com>
Cc: Neo Jia <cjia@nvidia.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
1 parent e19f32d
Raw File
Tip revision: c6ef7fd40eddad38a8825cbd6bb2ce8bdbba88f5 authored by Paul Gortmaker on 04 January 2017, 20:08:15 UTC
vfio-mdev: fix non-standard ioctl return val causing i386 build fail
Tip revision: c6ef7fd
interval_tree_test.c 
#include <linux/module.h>
#include <linux/interval_tree.h>
#include <linux/random.h>
#include <asm/timex.h>

#define NODES        100
#define PERF_LOOPS   100000
#define SEARCHES     100
#define SEARCH_LOOPS 10000

static struct rb_root root = RB_ROOT;
static struct interval_tree_node nodes[NODES];
static u32 queries[SEARCHES];

static struct rnd_state rnd;

static inline unsigned long
search(unsigned long query, struct rb_root *root)
{
	struct interval_tree_node *node;
	unsigned long results = 0;

	for (node = interval_tree_iter_first(root, query, query); node;
	     node = interval_tree_iter_next(node, query, query))
		results++;
	return results;
}

static void init(void)
{
	int i;
	for (i = 0; i < NODES; i++) {
		u32 a = prandom_u32_state(&rnd);
		u32 b = prandom_u32_state(&rnd);
		if (a <= b) {
			nodes[i].start = a;
			nodes[i].last = b;
		} else {
			nodes[i].start = b;
			nodes[i].last = a;
		}
	}
	for (i = 0; i < SEARCHES; i++)
		queries[i] = prandom_u32_state(&rnd);
}

static int interval_tree_test_init(void)
{
	int i, j;
	unsigned long results;
	cycles_t time1, time2, time;

	printk(KERN_ALERT "interval tree insert/remove");

	prandom_seed_state(&rnd, 3141592653589793238ULL);
	init();

	time1 = get_cycles();

	for (i = 0; i < PERF_LOOPS; i++) {
		for (j = 0; j < NODES; j++)
			interval_tree_insert(nodes + j, &root);
		for (j = 0; j < NODES; j++)
			interval_tree_remove(nodes + j, &root);
	}

	time2 = get_cycles();
	time = time2 - time1;

	time = div_u64(time, PERF_LOOPS);
	printk(" -> %llu cycles\n", (unsigned long long)time);

	printk(KERN_ALERT "interval tree search");

	for (j = 0; j < NODES; j++)
		interval_tree_insert(nodes + j, &root);

	time1 = get_cycles();

	results = 0;
	for (i = 0; i < SEARCH_LOOPS; i++)
		for (j = 0; j < SEARCHES; j++)
			results += search(queries[j], &root);

	time2 = get_cycles();
	time = time2 - time1;

	time = div_u64(time, SEARCH_LOOPS);
	results = div_u64(results, SEARCH_LOOPS);
	printk(" -> %llu cycles (%lu results)\n",
	       (unsigned long long)time, results);

	return -EAGAIN; /* Fail will directly unload the module */
}

static void interval_tree_test_exit(void)
{
	printk(KERN_ALERT "test exit\n");
}

module_init(interval_tree_test_init)
module_exit(interval_tree_test_exit)

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Michel Lespinasse");
MODULE_DESCRIPTION("Interval Tree test");
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