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@@ -0,0 +1,98 @@
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+/*
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+ * Copyright (c) 2013
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+ * Phillip Lougher <phillip@squashfs.org.uk>
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+ *
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+ * This work is licensed under the terms of the GNU GPL, version 2. See
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+ * the COPYING file in the top-level directory.
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+ */
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+
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+#include <linux/types.h>
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+#include <linux/slab.h>
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+#include <linux/percpu.h>
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+#include <linux/buffer_head.h>
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+
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+#include "squashfs_fs.h"
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+#include "squashfs_fs_sb.h"
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+#include "decompressor.h"
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+#include "squashfs.h"
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+
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+/*
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+ * This file implements multi-threaded decompression using percpu
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+ * variables, one thread per cpu core.
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+ */
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+
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+struct squashfs_stream {
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+ void *stream;
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+};
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+
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+void *squashfs_decompressor_create(struct squashfs_sb_info *msblk,
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+ void *comp_opts)
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+{
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+ struct squashfs_stream *stream;
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+ struct squashfs_stream __percpu *percpu;
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+ int err, cpu;
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+
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+ percpu = alloc_percpu(struct squashfs_stream);
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+ if (percpu == NULL)
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+ return ERR_PTR(-ENOMEM);
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+
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+ for_each_possible_cpu(cpu) {
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+ stream = per_cpu_ptr(percpu, cpu);
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+ stream->stream = msblk->decompressor->init(msblk, comp_opts);
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+ if (IS_ERR(stream->stream)) {
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+ err = PTR_ERR(stream->stream);
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+ goto out;
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+ }
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+ }
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+
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+ kfree(comp_opts);
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+ return (__force void *) percpu;
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+
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+out:
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+ for_each_possible_cpu(cpu) {
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+ stream = per_cpu_ptr(percpu, cpu);
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+ if (!IS_ERR_OR_NULL(stream->stream))
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+ msblk->decompressor->free(stream->stream);
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+ }
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+ free_percpu(percpu);
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+ return ERR_PTR(err);
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+}
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+
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+void squashfs_decompressor_destroy(struct squashfs_sb_info *msblk)
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+{
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+ struct squashfs_stream __percpu *percpu =
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+ (struct squashfs_stream __percpu *) msblk->stream;
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+ struct squashfs_stream *stream;
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+ int cpu;
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+
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+ if (msblk->stream) {
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+ for_each_possible_cpu(cpu) {
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+ stream = per_cpu_ptr(percpu, cpu);
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+ msblk->decompressor->free(stream->stream);
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+ }
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+ free_percpu(percpu);
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+ }
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+}
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+
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+int squashfs_decompress(struct squashfs_sb_info *msblk,
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+ void **buffer, struct buffer_head **bh, int b, int offset, int length,
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+ int srclength, int pages)
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+{
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+ struct squashfs_stream __percpu *percpu =
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+ (struct squashfs_stream __percpu *) msblk->stream;
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+ struct squashfs_stream *stream = get_cpu_ptr(percpu);
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+ int res = msblk->decompressor->decompress(msblk, stream->stream, buffer,
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+ bh, b, offset, length, srclength, pages);
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+ put_cpu_ptr(stream);
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+
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+ if (res < 0)
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+ ERROR("%s decompression failed, data probably corrupt\n",
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+ msblk->decompressor->name);
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+
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+ return res;
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+}
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+
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+int squashfs_max_decompressors(void)
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+{
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+ return num_possible_cpus();
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+}
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