1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * CMA SysFS Interface 4 * 5 * Copyright (c) 2021 Minchan Kim <minchan@kernel.org> 6 */ 7 8 #include <linux/cma.h> 9 #include <linux/kernel.h> 10 #include <linux/slab.h> 11 12 #include "cma.h" 13 14 #define CMA_ATTR_RO(_name) \ 15 static struct kobj_attribute _name##_attr = __ATTR_RO(_name) 16 17 void cma_sysfs_account_success_pages(struct cma *cma, unsigned long nr_pages) 18 { 19 atomic64_add(nr_pages, &cma->nr_pages_succeeded); 20 } 21 22 void cma_sysfs_account_fail_pages(struct cma *cma, unsigned long nr_pages) 23 { 24 atomic64_add(nr_pages, &cma->nr_pages_failed); 25 } 26 27 static inline struct cma *cma_from_kobj(struct kobject *kobj) 28 { 29 return container_of(kobj, struct cma_kobject, kobj)->cma; 30 } 31 32 static ssize_t alloc_pages_success_show(struct kobject *kobj, 33 struct kobj_attribute *attr, char *buf) 34 { 35 struct cma *cma = cma_from_kobj(kobj); 36 37 return sysfs_emit(buf, "%llu\n", 38 atomic64_read(&cma->nr_pages_succeeded)); 39 } 40 CMA_ATTR_RO(alloc_pages_success); 41 42 static ssize_t alloc_pages_fail_show(struct kobject *kobj, 43 struct kobj_attribute *attr, char *buf) 44 { 45 struct cma *cma = cma_from_kobj(kobj); 46 47 return sysfs_emit(buf, "%llu\n", atomic64_read(&cma->nr_pages_failed)); 48 } 49 CMA_ATTR_RO(alloc_pages_fail); 50 51 static void cma_kobj_release(struct kobject *kobj) 52 { 53 struct cma *cma = cma_from_kobj(kobj); 54 struct cma_kobject *cma_kobj = cma->cma_kobj; 55 56 kfree(cma_kobj); 57 cma->cma_kobj = NULL; 58 } 59 60 static struct attribute *cma_attrs[] = { 61 &alloc_pages_success_attr.attr, 62 &alloc_pages_fail_attr.attr, 63 NULL, 64 }; 65 ATTRIBUTE_GROUPS(cma); 66 67 static const struct kobj_type cma_ktype = { 68 .release = cma_kobj_release, 69 .sysfs_ops = &kobj_sysfs_ops, 70 .default_groups = cma_groups, 71 }; 72 73 static int __init cma_sysfs_init(void) 74 { 75 struct kobject *cma_kobj_root; 76 struct cma_kobject *cma_kobj; 77 struct cma *cma; 78 int i, err; 79 80 cma_kobj_root = kobject_create_and_add("cma", mm_kobj); 81 if (!cma_kobj_root) 82 return -ENOMEM; 83 84 for (i = 0; i < cma_area_count; i++) { 85 cma_kobj = kzalloc(sizeof(*cma_kobj), GFP_KERNEL); 86 if (!cma_kobj) { 87 err = -ENOMEM; 88 goto out; 89 } 90 91 cma = &cma_areas[i]; 92 cma->cma_kobj = cma_kobj; 93 cma_kobj->cma = cma; 94 err = kobject_init_and_add(&cma_kobj->kobj, &cma_ktype, 95 cma_kobj_root, "%s", cma->name); 96 if (err) { 97 kobject_put(&cma_kobj->kobj); 98 goto out; 99 } 100 } 101 102 return 0; 103 out: 104 while (--i >= 0) { 105 cma = &cma_areas[i]; 106 kobject_put(&cma->cma_kobj->kobj); 107 } 108 kobject_put(cma_kobj_root); 109 110 return err; 111 } 112 subsys_initcall(cma_sysfs_init); 113