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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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4.9 kB · 230 lines
C
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231// SPDX-License-Identifier: GPL-2.0-only/* * Copyright (c) 2023, Qualcomm Innovation Center, Inc. All rights reserved. */#include <linux/debugfs.h>#include <linux/interconnect.h>#include <linux/platform_device.h>#include <linux/slab.h>
#include "internal.h"
/* * This can be dangerous, therefore don't provide any real compile time * configuration option for this feature. * People who want to use this will need to modify the source code directly. */#undef INTERCONNECT_ALLOW_WRITE_DEBUGFS
#if defined(INTERCONNECT_ALLOW_WRITE_DEBUGFS) && defined(CONFIG_DEBUG_FS)
static LIST_HEAD(debugfs_paths);static DEFINE_MUTEX(debugfs_lock);
static struct platform_device *pdev;static struct icc_path *cur_path;
static char *src_node;static char *dst_node;static u32 avg_bw;static u32 peak_bw;static u32 tag;
struct debugfs_path { const char *src; const char *dst; struct icc_path *path; struct list_head list;};
static ssize_t icc_node_read(struct file *file, char __user *user_buf, size_t count, loff_t *ppos){ char **node = file->private_data; char *copy; size_t len; ssize_t ret;
scoped_guard(mutex, &debugfs_lock) { copy = kstrdup(*node ?: "", GFP_KERNEL); } if (!copy) return -ENOMEM;
len = strlen(copy); copy[len++] = '\n'; ret = simple_read_from_buffer(user_buf, count, ppos, copy, len); kfree(copy); return ret;}
static ssize_t icc_node_write(struct file *file, const char __user *user_buf, size_t count, loff_t *ppos){ char **node = file->private_data; char *old, *new;
if (*ppos) return -EINVAL; if (count + 1 > PAGE_SIZE) return -E2BIG;
new = memdup_user_nul(user_buf, count); if (IS_ERR(new)) return PTR_ERR(new); strim(new);
scoped_guard(mutex, &debugfs_lock) { old = *node; *node = new; }
kfree(old); return count;}
static const struct file_operations icc_node_fops = { .open = simple_open, .read = icc_node_read, .write = icc_node_write, .llseek = default_llseek,};
static struct icc_path *get_path(const char *src, const char *dst){ struct debugfs_path *path;
list_for_each_entry(path, &debugfs_paths, list) { if (!strcmp(path->src, src) && !strcmp(path->dst, dst)) return path->path; }
return NULL;}
static int icc_get_set(void *data, u64 val){ struct debugfs_path *debugfs_path; char *src, *dst; int ret = 0;
guard(mutex)(&debugfs_lock);
/* * If we've already looked up a path, then use the existing one instead * of calling icc_get() again. This allows for updating previous BW * votes when "get" is written to multiple times for multiple paths. */ cur_path = get_path(src_node, dst_node); if (cur_path) goto out;
src = kstrdup(src_node, GFP_KERNEL); dst = kstrdup(dst_node, GFP_KERNEL);
if (!src || !dst) { ret = -ENOMEM; goto err_free; }
cur_path = icc_get(&pdev->dev, src, dst); if (IS_ERR(cur_path)) { ret = PTR_ERR(cur_path); goto err_free; }
debugfs_path = kzalloc_obj(*debugfs_path); if (!debugfs_path) { ret = -ENOMEM; goto err_put; }
debugfs_path->path = cur_path; debugfs_path->src = src; debugfs_path->dst = dst; list_add_tail(&debugfs_path->list, &debugfs_paths);
goto out;
err_put: icc_put(cur_path);err_free: kfree(src); kfree(dst);out: return ret;}
DEFINE_DEBUGFS_ATTRIBUTE(icc_get_fops, NULL, icc_get_set, "%llu\n");
static int icc_commit_set(void *data, u64 val){ int ret;
guard(mutex)(&debugfs_lock);
if (!cur_path) { ret = -EINVAL; goto out; }
if (IS_ERR(cur_path)) { ret = PTR_ERR(cur_path); goto out; }
icc_set_tag(cur_path, tag); ret = icc_set_bw(cur_path, avg_bw, peak_bw);out: return ret;}
DEFINE_DEBUGFS_ATTRIBUTE(icc_commit_fops, NULL, icc_commit_set, "%llu\n");
int icc_debugfs_client_init(struct dentry *icc_dir){ struct dentry *client_dir; int ret;
pdev = platform_device_alloc("icc-debugfs-client", PLATFORM_DEVID_NONE); if (!pdev) return -ENOMEM;
ret = platform_device_add(pdev); if (ret) { pr_err("%s: failed to add platform device: %d\n", __func__, ret); platform_device_put(pdev); return ret; }
src_node = kstrdup("", GFP_KERNEL); dst_node = kstrdup("", GFP_KERNEL); if (!src_node || !dst_node) { kfree(dst_node); kfree(src_node); return -ENOMEM; }
client_dir = debugfs_create_dir("test_client", icc_dir);
debugfs_create_file("src_node", 0600, client_dir, &src_node, &icc_node_fops); debugfs_create_file("dst_node", 0600, client_dir, &dst_node, &icc_node_fops); debugfs_create_file("get", 0200, client_dir, NULL, &icc_get_fops); debugfs_create_u32("avg_bw", 0600, client_dir, &avg_bw); debugfs_create_u32("peak_bw", 0600, client_dir, &peak_bw); debugfs_create_u32("tag", 0600, client_dir, &tag); debugfs_create_file("commit", 0200, client_dir, NULL, &icc_commit_fops);
return 0;}
#else
int icc_debugfs_client_init(struct dentry *icc_dir){ return 0;}
#endif