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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
| commit | f4cdf7ca9a1fdcca413157df19753f388a5a224e (patch) | |
| tree | 60a31895b2446cd7fa27514e8c2843534a0de0da /fs/jffs2/compr_rtime.c | |
| download | linux-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 'fs/jffs2/compr_rtime.c')
| -rw-r--r-- | fs/jffs2/compr_rtime.c | 136 |
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); +} |
