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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /net/ceph/ceph_hash.c
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'net/ceph/ceph_hash.c')
-rw-r--r--net/ceph/ceph_hash.c131
1 files changed, 131 insertions, 0 deletions
diff --git a/net/ceph/ceph_hash.c b/net/ceph/ceph_hash.c
new file mode 100644
index 000000000..16a47c0ee
--- /dev/null
+++ b/net/ceph/ceph_hash.c
@@ -0,0 +1,131 @@
+
+#include <linux/ceph/types.h>
+#include <linux/module.h>
+
+/*
+ * Robert Jenkin's hash function.
+ * https://burtleburtle.net/bob/hash/evahash.html
+ * This is in the public domain.
+ */
+#define mix(a, b, c) \
+ do { \
+ a = a - b; a = a - c; a = a ^ (c >> 13); \
+ b = b - c; b = b - a; b = b ^ (a << 8); \
+ c = c - a; c = c - b; c = c ^ (b >> 13); \
+ a = a - b; a = a - c; a = a ^ (c >> 12); \
+ b = b - c; b = b - a; b = b ^ (a << 16); \
+ c = c - a; c = c - b; c = c ^ (b >> 5); \
+ a = a - b; a = a - c; a = a ^ (c >> 3); \
+ b = b - c; b = b - a; b = b ^ (a << 10); \
+ c = c - a; c = c - b; c = c ^ (b >> 15); \
+ } while (0)
+
+unsigned int ceph_str_hash_rjenkins(const char *str, unsigned int length)
+{
+ const unsigned char *k = (const unsigned char *)str;
+ __u32 a, b, c; /* the internal state */
+ __u32 len; /* how many key bytes still need mixing */
+
+ /* Set up the internal state */
+ len = length;
+ a = 0x9e3779b9; /* the golden ratio; an arbitrary value */
+ b = a;
+ c = 0; /* variable initialization of internal state */
+
+ /* handle most of the key */
+ while (len >= 12) {
+ a = a + (k[0] + ((__u32)k[1] << 8) + ((__u32)k[2] << 16) +
+ ((__u32)k[3] << 24));
+ b = b + (k[4] + ((__u32)k[5] << 8) + ((__u32)k[6] << 16) +
+ ((__u32)k[7] << 24));
+ c = c + (k[8] + ((__u32)k[9] << 8) + ((__u32)k[10] << 16) +
+ ((__u32)k[11] << 24));
+ mix(a, b, c);
+ k = k + 12;
+ len = len - 12;
+ }
+
+ /* handle the last 11 bytes */
+ c = c + length;
+ switch (len) {
+ case 11:
+ c = c + ((__u32)k[10] << 24);
+ fallthrough;
+ case 10:
+ c = c + ((__u32)k[9] << 16);
+ fallthrough;
+ case 9:
+ c = c + ((__u32)k[8] << 8);
+ /* the first byte of c is reserved for the length */
+ fallthrough;
+ case 8:
+ b = b + ((__u32)k[7] << 24);
+ fallthrough;
+ case 7:
+ b = b + ((__u32)k[6] << 16);
+ fallthrough;
+ case 6:
+ b = b + ((__u32)k[5] << 8);
+ fallthrough;
+ case 5:
+ b = b + k[4];
+ fallthrough;
+ case 4:
+ a = a + ((__u32)k[3] << 24);
+ fallthrough;
+ case 3:
+ a = a + ((__u32)k[2] << 16);
+ fallthrough;
+ case 2:
+ a = a + ((__u32)k[1] << 8);
+ fallthrough;
+ case 1:
+ a = a + k[0];
+ /* case 0: nothing left to add */
+ }
+ mix(a, b, c);
+
+ return c;
+}
+
+/*
+ * linux dcache hash
+ */
+unsigned int ceph_str_hash_linux(const char *str, unsigned int length)
+{
+ unsigned long hash = 0;
+ unsigned char c;
+
+ while (length--) {
+ c = *str++;
+ hash = (hash + (c << 4) + (c >> 4)) * 11;
+ }
+ return hash;
+}
+
+
+unsigned int ceph_str_hash(int type, const char *s, unsigned int len)
+{
+ switch (type) {
+ case CEPH_STR_HASH_LINUX:
+ return ceph_str_hash_linux(s, len);
+ case CEPH_STR_HASH_RJENKINS:
+ return ceph_str_hash_rjenkins(s, len);
+ default:
+ return -1;
+ }
+}
+EXPORT_SYMBOL(ceph_str_hash);
+
+const char *ceph_str_hash_name(int type)
+{
+ switch (type) {
+ case CEPH_STR_HASH_LINUX:
+ return "linux";
+ case CEPH_STR_HASH_RJENKINS:
+ return "rjenkins";
+ default:
+ return "unknown";
+ }
+}
+EXPORT_SYMBOL(ceph_str_hash_name);