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 void cma_sysfs_account_release_pages(struct cma *cma, unsigned long nr_pages) 28 { 29 atomic64_add(nr_pages, &cma->nr_pages_released); 30 } 31 32 static inline struct cma *cma_from_kobj(struct kobject *kobj) 33 { 34 return container_of(kobj, struct cma_kobject, kobj)->cma; 35 } 36 37 static ssize_t alloc_pages_success_show(struct kobject *kobj, 38 struct kobj_attribute *attr, char *buf) 39 { 40 struct cma *cma = cma_from_kobj(kobj); 41 42 return sysfs_emit(buf, "%llu\n", 43 atomic64_read(&cma->nr_pages_succeeded)); 44 } 45 CMA_ATTR_RO(alloc_pages_success); 46 47 static ssize_t alloc_pages_fail_show(struct kobject *kobj, 48 struct kobj_attribute *attr, char *buf) 49 { 50 struct cma *cma = cma_from_kobj(kobj); 51 52 return sysfs_emit(buf, "%llu\n", atomic64_read(&cma->nr_pages_failed)); 53 } 54 CMA_ATTR_RO(alloc_pages_fail); 55 56 static ssize_t release_pages_success_show(struct kobject *kobj, 57 struct kobj_attribute *attr, char *buf) 58 { 59 struct cma *cma = cma_from_kobj(kobj); 60 61 return sysfs_emit(buf, "%llu\n", atomic64_read(&cma->nr_pages_released)); 62 } 63 CMA_ATTR_RO(release_pages_success); 64 65 static void cma_kobj_release(struct kobject *kobj) 66 { 67 struct cma *cma = cma_from_kobj(kobj); 68 struct cma_kobject *cma_kobj = cma->cma_kobj; 69 70 kfree(cma_kobj); 71 cma->cma_kobj = NULL; 72 } 73 74 static struct attribute *cma_attrs[] = { 75 &alloc_pages_success_attr.attr, 76 &alloc_pages_fail_attr.attr, 77 &release_pages_success_attr.attr, 78 NULL, 79 }; 80 ATTRIBUTE_GROUPS(cma); 81 82 static const struct kobj_type cma_ktype = { 83 .release = cma_kobj_release, 84 .sysfs_ops = &kobj_sysfs_ops, 85 .default_groups = cma_groups, 86 }; 87 88 static int __init cma_sysfs_init(void) 89 { 90 struct kobject *cma_kobj_root; 91 struct cma_kobject *cma_kobj; 92 struct cma *cma; 93 int i, err; 94 95 cma_kobj_root = kobject_create_and_add("cma", mm_kobj); 96 if (!cma_kobj_root) 97 return -ENOMEM; 98 99 for (i = 0; i < cma_area_count; i++) { 100 cma_kobj = kzalloc(sizeof(*cma_kobj), GFP_KERNEL); 101 if (!cma_kobj) { 102 err = -ENOMEM; 103 goto out; 104 } 105 106 cma = &cma_areas[i]; 107 cma->cma_kobj = cma_kobj; 108 cma_kobj->cma = cma; 109 err = kobject_init_and_add(&cma_kobj->kobj, &cma_ktype, 110 cma_kobj_root, "%s", cma->name); 111 if (err) { 112 kobject_put(&cma_kobj->kobj); 113 goto out; 114 } 115 } 116 117 return 0; 118 out: 119 while (--i >= 0) { 120 cma = &cma_areas[i]; 121 kobject_put(&cma->cma_kobj->kobj); 122 } 123 kobject_put(cma_kobj_root); 124 125 return err; 126 } 127 subsys_initcall(cma_sysfs_init); 128