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authorLinus Torvalds <torvalds@linux-foundation.org>2026-09-20 08:15:23 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-09-20 08:15:23 -0700
commitbdab18633a302c82b5e5d5dbc4e38b0baf9c0837 (patch)
tree0446500af9a76d4e8b2a72a0a41391ceede73a10 /crypto/842.c
downloadlinux-stable-bdab18633a302c82b5e5d5dbc4e38b0baf9c0837.tar.gz
linux-stable-bdab18633a302c82b5e5d5dbc4e38b0baf9c0837.zip
Merge tag 'locking-urgent-2026-09-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipgrafted
Pull futex fix from Ingo Molnar: - Also allocate a default private futex hash on vfork() as well, to avoid races with (private) futex waiters (Peter Zijlstra) * tag 'locking-urgent-2026-09-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: futex: Also allocate private hash on vfork()
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
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+++ 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>");