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authorCheng Lingfei <chenglingfei@foxmail.com>2026-08-24 20:45:46 +0800
committerTejun Heo <tj@kernel.org>2026-08-24 06:55:59 -1000
commit909a3f0e9d8b0d8001cf6e99808f88eca8e44328 (patch)
treebe05d18bd5619b55ff3b30f28a292907021768ee /crypto/842.c
downloadlinux-stable-909a3f0e9d8b0d8001cf6e99808f88eca8e44328.tar.gz
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docs: cgroup-v2: fix misc.events key format descriptiongrafted
In misc cgroup, misc.events does not output a simple "max" key. Instead, each registered misc resource outputs a separate key suffixed with ".max" (i.e., "<res>.max"). Update the documentation to clarify that the entry key is "<res>.max". Suggested-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Cheng Lingfei <chenglingfei@foxmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'crypto/842.c')
-rw-r--r--crypto/842.c87
1 files changed, 87 insertions, 0 deletions
diff --git a/crypto/842.c b/crypto/842.c
new file mode 100644
index 000000000..4007e87be
--- /dev/null
+++ b/crypto/842.c
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+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Cryptographic API for the 842 software compression algorithm.
+ *
+ * Copyright (C) IBM Corporation, 2011-2015
+ *
+ * Original Authors: Robert Jennings <rcj@linux.vnet.ibm.com>
+ * Seth Jennings <sjenning@linux.vnet.ibm.com>
+ *
+ * Rewrite: Dan Streetman <ddstreet@ieee.org>
+ *
+ * This is the software implementation of compression and decompression using
+ * the 842 format. This uses the software 842 library at lib/842/ which is
+ * only a reference implementation, and is very, very slow as compared to other
+ * software compressors. You probably do not want to use this software
+ * compression. If you have access to the PowerPC 842 compression hardware, you
+ * want to use the 842 hardware compression interface, which is at:
+ * drivers/crypto/nx/nx-842-crypto.c
+ */
+
+#include <crypto/internal/scompress.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/sw842.h>
+
+static void *crypto842_alloc_ctx(void)
+{
+ void *ctx;
+
+ ctx = kmalloc(SW842_MEM_COMPRESS, GFP_KERNEL);
+ if (!ctx)
+ return ERR_PTR(-ENOMEM);
+
+ return ctx;
+}
+
+static void crypto842_free_ctx(void *ctx)
+{
+ kfree(ctx);
+}
+
+static int crypto842_scompress(struct crypto_scomp *tfm,
+ const u8 *src, unsigned int slen,
+ u8 *dst, unsigned int *dlen, void *ctx)
+{
+ return sw842_compress(src, slen, dst, dlen, ctx);
+}
+
+static int crypto842_sdecompress(struct crypto_scomp *tfm,
+ const u8 *src, unsigned int slen,
+ u8 *dst, unsigned int *dlen, void *ctx)
+{
+ return sw842_decompress(src, slen, dst, dlen);
+}
+
+static struct scomp_alg scomp = {
+ .streams = {
+ .alloc_ctx = crypto842_alloc_ctx,
+ .free_ctx = crypto842_free_ctx,
+ },
+ .compress = crypto842_scompress,
+ .decompress = crypto842_sdecompress,
+ .base = {
+ .cra_name = "842",
+ .cra_driver_name = "842-scomp",
+ .cra_priority = 100,
+ .cra_module = THIS_MODULE,
+ }
+};
+
+static int __init crypto842_mod_init(void)
+{
+ return crypto_register_scomp(&scomp);
+}
+module_init(crypto842_mod_init);
+
+static void __exit crypto842_mod_exit(void)
+{
+ crypto_unregister_scomp(&scomp);
+}
+module_exit(crypto842_mod_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("842 Software Compression Algorithm");
+MODULE_ALIAS_CRYPTO("842");
+MODULE_ALIAS_CRYPTO("842-generic");
+MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");