50865c14f3
Documentation/filesystems/seq_file.rst describes the possible return values from a "show()" function used by single_open(). show_trace() returns the value of "trace_count". This could be interpreted as "SEQ_SKIP", or just confuse the calling function. Change to just return "0" to avoid confusing anyone reading this code and possibly using as a template. Reading "daemon_active" was never an intended use case. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20221018165900.109029-1-tony.luck@intel.com
60 lines
1.1 KiB
C
60 lines
1.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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#include <linux/debugfs.h>
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#include <linux/ras.h>
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#include "debugfs.h"
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struct dentry *ras_debugfs_dir;
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static atomic_t trace_count = ATOMIC_INIT(0);
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int ras_userspace_consumers(void)
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{
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return atomic_read(&trace_count);
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}
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EXPORT_SYMBOL_GPL(ras_userspace_consumers);
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static int trace_show(struct seq_file *m, void *v)
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{
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return 0;
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}
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static int trace_open(struct inode *inode, struct file *file)
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{
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atomic_inc(&trace_count);
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return single_open(file, trace_show, NULL);
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}
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static int trace_release(struct inode *inode, struct file *file)
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{
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atomic_dec(&trace_count);
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return single_release(inode, file);
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}
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static const struct file_operations trace_fops = {
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.open = trace_open,
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.read = seq_read,
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.llseek = seq_lseek,
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.release = trace_release,
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};
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int __init ras_add_daemon_trace(void)
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{
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struct dentry *fentry;
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if (!ras_debugfs_dir)
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return -ENOENT;
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fentry = debugfs_create_file("daemon_active", S_IRUSR, ras_debugfs_dir,
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NULL, &trace_fops);
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if (!fentry)
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return -ENODEV;
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return 0;
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}
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void __init ras_debugfs_init(void)
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{
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ras_debugfs_dir = debugfs_create_dir("ras", NULL);
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}
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