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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 /fs/jffs2/compr_rtime.c
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
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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 'fs/jffs2/compr_rtime.c')
-rw-r--r--fs/jffs2/compr_rtime.c136
1 files changed, 136 insertions, 0 deletions
diff --git a/fs/jffs2/compr_rtime.c b/fs/jffs2/compr_rtime.c
new file mode 100644
index 000000000..3bd9d2f3b
--- /dev/null
+++ b/fs/jffs2/compr_rtime.c
@@ -0,0 +1,136 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright © 2001-2007 Red Hat, Inc.
+ * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
+ *
+ * Created by Arjan van de Ven <arjanv@redhat.com>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ *
+ *
+ * Very simple lz77-ish encoder.
+ *
+ * Theory of operation: Both encoder and decoder have a list of "last
+ * occurrences" for every possible source-value; after sending the
+ * first source-byte, the second byte indicated the "run" length of
+ * matches
+ *
+ * The algorithm is intended to only send "whole bytes", no bit-messing.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/jffs2.h>
+#include "compr.h"
+
+/* _compress returns the compressed size, -1 if bigger */
+static int jffs2_rtime_compress(unsigned char *data_in,
+ unsigned char *cpage_out,
+ uint32_t *sourcelen, uint32_t *dstlen)
+{
+ unsigned short positions[256];
+ int outpos = 0;
+ int pos=0;
+
+ if (*dstlen <= 3)
+ return -1;
+
+ memset(positions,0,sizeof(positions));
+
+ while (pos < (*sourcelen) && outpos <= (*dstlen)-2) {
+ int backpos, runlen=0;
+ unsigned char value;
+
+ value = data_in[pos];
+
+ cpage_out[outpos++] = data_in[pos++];
+
+ backpos = positions[value];
+ positions[value]=pos;
+
+ while ((backpos < pos) && (pos < (*sourcelen)) &&
+ (data_in[pos]==data_in[backpos++]) && (runlen<255)) {
+ pos++;
+ runlen++;
+ }
+ cpage_out[outpos++] = runlen;
+ }
+
+ if (outpos >= pos) {
+ /* We failed */
+ return -1;
+ }
+
+ /* Tell the caller how much we managed to compress, and how much space it took */
+ *sourcelen = pos;
+ *dstlen = outpos;
+ return 0;
+}
+
+
+static int jffs2_rtime_decompress(unsigned char *data_in,
+ unsigned char *cpage_out,
+ uint32_t srclen, uint32_t destlen)
+{
+ unsigned short positions[256];
+ int outpos = 0;
+ int pos=0;
+
+ memset(positions,0,sizeof(positions));
+
+ while (outpos<destlen) {
+ unsigned char value;
+ int backoffs;
+ int repeat;
+
+ value = data_in[pos++];
+ cpage_out[outpos++] = value; /* first the verbatim copied byte */
+ repeat = data_in[pos++];
+ backoffs = positions[value];
+
+ positions[value]=outpos;
+ if (repeat) {
+ if ((outpos + repeat) > destlen) {
+ return 1;
+ }
+ if (backoffs + repeat >= outpos) {
+ while(repeat) {
+ cpage_out[outpos++] = cpage_out[backoffs++];
+ repeat--;
+ }
+ } else {
+ memcpy(&cpage_out[outpos],&cpage_out[backoffs],repeat);
+ outpos+=repeat;
+ }
+ }
+ }
+ return 0;
+}
+
+static struct jffs2_compressor jffs2_rtime_comp = {
+ .priority = JFFS2_RTIME_PRIORITY,
+ .name = "rtime",
+ .compr = JFFS2_COMPR_RTIME,
+ .compress = &jffs2_rtime_compress,
+ .decompress = &jffs2_rtime_decompress,
+#ifdef JFFS2_RTIME_DISABLED
+ .disabled = 1,
+#else
+ .disabled = 0,
+#endif
+};
+
+int jffs2_rtime_init(void)
+{
+ return jffs2_register_compressor(&jffs2_rtime_comp);
+}
+
+void jffs2_rtime_exit(void)
+{
+ jffs2_unregister_compressor(&jffs2_rtime_comp);
+}