Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 218 insertions, 0 deletions

diff --git a/fs/jffs2/compr_zlib.c b/fs/jffs2/compr_zlib.c
new file mode 100644
index 000000000000..9f9932c22adb
--- /dev/null
+++ b/fs/jffs2/compr_zlib.c
@@ -0,0 +1,218 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2001-2003 Red Hat, Inc.
+ *
+ * Created by David Woodhouse <dwmw2@infradead.org>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ * $Id: compr_zlib.c,v 1.29 2004/11/16 20:36:11 dwmw2 Exp $
+ *
+ */
+
+#if !defined(__KERNEL__) && !defined(__ECOS)
+#error "The userspace support got too messy and was removed. Update your mkfs.jffs2"
+#endif
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/zlib.h>
+#include <linux/zutil.h>
+#include <asm/semaphore.h>
+#include "nodelist.h"
+#include "compr.h"
+
+        /* Plan: call deflate() with avail_in == *sourcelen, 
+                avail_out = *dstlen - 12 and flush == Z_FINISH. 
+                If it doesn't manage to finish, call it again with
+                avail_in == 0 and avail_out set to the remaining 12
+                bytes for it to clean up. 
+           Q: Is 12 bytes sufficient?
+        */
+#define STREAM_END_SPACE 12
+
+static DECLARE_MUTEX(deflate_sem);
+static DECLARE_MUTEX(inflate_sem);
+static z_stream inf_strm, def_strm;
+
+#ifdef __KERNEL__ /* Linux-only */
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+
+static int __init alloc_workspaces(void)
+{
+        def_strm.workspace = vmalloc(zlib_deflate_workspacesize());
+        if (!def_strm.workspace) {
+                printk(KERN_WARNING "Failed to allocate %d bytes for deflate workspace\n", zlib_deflate_workspacesize());
+                return -ENOMEM;
+        }
+        D1(printk(KERN_DEBUG "Allocated %d bytes for deflate workspace\n", zlib_deflate_workspacesize()));
+        inf_strm.workspace = vmalloc(zlib_inflate_workspacesize());
+        if (!inf_strm.workspace) {
+                printk(KERN_WARNING "Failed to allocate %d bytes for inflate workspace\n", zlib_inflate_workspacesize());
+                vfree(def_strm.workspace);
+                return -ENOMEM;
+        }
+        D1(printk(KERN_DEBUG "Allocated %d bytes for inflate workspace\n", zlib_inflate_workspacesize()));
+        return 0;
+}
+
+static void free_workspaces(void)
+{
+        vfree(def_strm.workspace);
+        vfree(inf_strm.workspace);
+}
+#else
+#define alloc_workspaces() (0)
+#define free_workspaces() do { } while(0)
+#endif /* __KERNEL__ */
+
+int jffs2_zlib_compress(unsigned char *data_in, unsigned char *cpage_out, 
+                   uint32_t *sourcelen, uint32_t *dstlen, void *model)
+{
+        int ret;
+
+        if (*dstlen <= STREAM_END_SPACE)
+                return -1;
+
+        down(&deflate_sem);
+
+        if (Z_OK != zlib_deflateInit(&def_strm, 3)) {
+                printk(KERN_WARNING "deflateInit failed\n");
+                up(&deflate_sem);
+                return -1;
+        }
+
+        def_strm.next_in = data_in;
+        def_strm.total_in = 0;
+        
+        def_strm.next_out = cpage_out;
+        def_strm.total_out = 0;
+
+        while (def_strm.total_out < *dstlen - STREAM_END_SPACE && def_strm.total_in < *sourcelen) {
+                def_strm.avail_out = *dstlen - (def_strm.total_out + STREAM_END_SPACE);
+                def_strm.avail_in = min((unsigned)(*sourcelen-def_strm.total_in), def_strm.avail_out);
+                D1(printk(KERN_DEBUG "calling deflate with avail_in %d, avail_out %d\n",
+                          def_strm.avail_in, def_strm.avail_out));
+                ret = zlib_deflate(&def_strm, Z_PARTIAL_FLUSH);
+                D1(printk(KERN_DEBUG "deflate returned with avail_in %d, avail_out %d, total_in %ld, total_out %ld\n", 
+                          def_strm.avail_in, def_strm.avail_out, def_strm.total_in, def_strm.total_out));
+                if (ret != Z_OK) {
+                        D1(printk(KERN_DEBUG "deflate in loop returned %d\n", ret));
+                        zlib_deflateEnd(&def_strm);
+                        up(&deflate_sem);
+                        return -1;
+                }
+        }
+        def_strm.avail_out += STREAM_END_SPACE;
+        def_strm.avail_in = 0;
+        ret = zlib_deflate(&def_strm, Z_FINISH);
+        zlib_deflateEnd(&def_strm);
+
+        if (ret != Z_STREAM_END) {
+                D1(printk(KERN_DEBUG "final deflate returned %d\n", ret));
+                ret = -1;
+                goto out;
+        }
+
+        if (def_strm.total_out >= def_strm.total_in) {
+                D1(printk(KERN_DEBUG "zlib compressed %ld bytes into %ld; failing\n",
+                          def_strm.total_in, def_strm.total_out));
+                ret = -1;
+                goto out;
+        }
+
+        D1(printk(KERN_DEBUG "zlib compressed %ld bytes into %ld\n",
+                  def_strm.total_in, def_strm.total_out));
+
+        *dstlen = def_strm.total_out;
+        *sourcelen = def_strm.total_in;
+        ret = 0;
+ out:
+        up(&deflate_sem);
+        return ret;
+}
+
+int jffs2_zlib_decompress(unsigned char *data_in, unsigned char *cpage_out,
+                      uint32_t srclen, uint32_t destlen, void *model)
+{
+        int ret;
+        int wbits = MAX_WBITS;
+
+        down(&inflate_sem);
+
+        inf_strm.next_in = data_in;
+        inf_strm.avail_in = srclen;
+        inf_strm.total_in = 0;
+        
+        inf_strm.next_out = cpage_out;
+        inf_strm.avail_out = destlen;
+        inf_strm.total_out = 0;
+
+        /* If it's deflate, and it's got no preset dictionary, then
+           we can tell zlib to skip the adler32 check. */
+        if (srclen > 2 && !(data_in[1] & PRESET_DICT) &&
+            ((data_in[0] & 0x0f) == Z_DEFLATED) &&
+            !(((data_in[0]<<8) + data_in[1]) % 31)) {
+
+                D2(printk(KERN_DEBUG "inflate skipping adler32\n"));
+                wbits = -((data_in[0] >> 4) + 8);
+                inf_strm.next_in += 2;
+                inf_strm.avail_in -= 2;
+        } else {
+                /* Let this remain D1 for now -- it should never happen */
+                D1(printk(KERN_DEBUG "inflate not skipping adler32\n"));
+        }
+
+
+        if (Z_OK != zlib_inflateInit2(&inf_strm, wbits)) {
+                printk(KERN_WARNING "inflateInit failed\n");
+                up(&inflate_sem);
+                return 1;
+        }
+
+        while((ret = zlib_inflate(&inf_strm, Z_FINISH)) == Z_OK)
+                ;
+        if (ret != Z_STREAM_END) {
+                printk(KERN_NOTICE "inflate returned %d\n", ret);
+        }
+        zlib_inflateEnd(&inf_strm);
+        up(&inflate_sem);
+        return 0;
+}
+
+static struct jffs2_compressor jffs2_zlib_comp = {
+    .priority = JFFS2_ZLIB_PRIORITY,
+    .name = "zlib",
+    .compr = JFFS2_COMPR_ZLIB,
+    .compress = &jffs2_zlib_compress,
+    .decompress = &jffs2_zlib_decompress,
+#ifdef JFFS2_ZLIB_DISABLED
+    .disabled = 1,
+#else
+    .disabled = 0,
+#endif
+};
+
+int __init jffs2_zlib_init(void)
+{
+    int ret;
+
+    ret = alloc_workspaces();
+    if (ret)
+        return ret;
+
+    ret = jffs2_register_compressor(&jffs2_zlib_comp);
+    if (ret)
+        free_workspaces();
+
+    return ret;
+}
+
+void jffs2_zlib_exit(void)
+{
+    jffs2_unregister_compressor(&jffs2_zlib_comp);
+    free_workspaces();
+}