1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Authors: 4 * Branden Bonaby <brandonbonaby94@gmail.com> 5 */ 6 7 #include <linux/hyperv.h> 8 #include <linux/debugfs.h> 9 #include <linux/delay.h> 10 #include <linux/err.h> 11 12 #include "hyperv_vmbus.h" 13 14 static struct dentry *hv_debug_root; 15 16 static int hv_debugfs_delay_get(void *data, u64 *val) 17 { 18 *val = *(u32 *)data; 19 return 0; 20 } 21 22 static int hv_debugfs_delay_set(void *data, u64 val) 23 { 24 if (val > 1000) 25 return -EINVAL; 26 *(u32 *)data = val; 27 return 0; 28 } 29 30 DEFINE_DEBUGFS_ATTRIBUTE(hv_debugfs_delay_fops, hv_debugfs_delay_get, 31 hv_debugfs_delay_set, "%llu\n"); 32 33 static int hv_debugfs_state_get(void *data, u64 *val) 34 { 35 *val = *(bool *)data; 36 return 0; 37 } 38 39 static int hv_debugfs_state_set(void *data, u64 val) 40 { 41 if (val == 1) 42 *(bool *)data = true; 43 else if (val == 0) 44 *(bool *)data = false; 45 else 46 return -EINVAL; 47 return 0; 48 } 49 50 DEFINE_DEBUGFS_ATTRIBUTE(hv_debugfs_state_fops, hv_debugfs_state_get, 51 hv_debugfs_state_set, "%llu\n"); 52 53 /* Setup delay files to store test values */ 54 static int hv_debug_delay_files(struct hv_device *dev, struct dentry *root) 55 { 56 struct vmbus_channel *channel = dev->channel; 57 char *buffer = "fuzz_test_buffer_interrupt_delay"; 58 char *message = "fuzz_test_message_delay"; 59 int *buffer_val = &channel->fuzz_testing_interrupt_delay; 60 int *message_val = &channel->fuzz_testing_message_delay; 61 struct dentry *buffer_file, *message_file; 62 63 buffer_file = debugfs_create_file(buffer, 0644, root, 64 buffer_val, 65 &hv_debugfs_delay_fops); 66 if (IS_ERR(buffer_file)) { 67 pr_debug("debugfs_hyperv: file %s not created\n", buffer); 68 return PTR_ERR(buffer_file); 69 } 70 71 message_file = debugfs_create_file(message, 0644, root, 72 message_val, 73 &hv_debugfs_delay_fops); 74 if (IS_ERR(message_file)) { 75 pr_debug("debugfs_hyperv: file %s not created\n", message); 76 return PTR_ERR(message_file); 77 } 78 79 return 0; 80 } 81 82 /* Setup test state value for vmbus device */ 83 static int hv_debug_set_test_state(struct hv_device *dev, struct dentry *root) 84 { 85 struct vmbus_channel *channel = dev->channel; 86 bool *state = &channel->fuzz_testing_state; 87 char *status = "fuzz_test_state"; 88 struct dentry *test_state; 89 90 test_state = debugfs_create_file(status, 0644, root, 91 state, 92 &hv_debugfs_state_fops); 93 if (IS_ERR(test_state)) { 94 pr_debug("debugfs_hyperv: file %s not created\n", status); 95 return PTR_ERR(test_state); 96 } 97 98 return 0; 99 } 100 101 /* Bind hv device to a dentry for debugfs */ 102 static void hv_debug_set_dir_dentry(struct hv_device *dev, struct dentry *root) 103 { 104 if (hv_debug_root) 105 dev->debug_dir = root; 106 } 107 108 /* Create all test dentry's and names for fuzz testing */ 109 int hv_debug_add_dev_dir(struct hv_device *dev) 110 { 111 const char *device = dev_name(&dev->device); 112 char *delay_name = "delay"; 113 struct dentry *delay, *dev_root; 114 int ret; 115 116 if (!IS_ERR(hv_debug_root)) { 117 dev_root = debugfs_create_dir(device, hv_debug_root); 118 if (IS_ERR(dev_root)) { 119 pr_debug("debugfs_hyperv: hyperv/%s/ not created\n", 120 device); 121 return PTR_ERR(dev_root); 122 } 123 hv_debug_set_test_state(dev, dev_root); 124 hv_debug_set_dir_dentry(dev, dev_root); 125 delay = debugfs_create_dir(delay_name, dev_root); 126 127 if (IS_ERR(delay)) { 128 pr_debug("debugfs_hyperv: hyperv/%s/%s/ not created\n", 129 device, delay_name); 130 return PTR_ERR(delay); 131 } 132 ret = hv_debug_delay_files(dev, delay); 133 134 return ret; 135 } 136 pr_debug("debugfs_hyperv: hyperv/ not in root debugfs path\n"); 137 return PTR_ERR(hv_debug_root); 138 } 139 140 /* Remove dentry associated with released hv device */ 141 void hv_debug_rm_dev_dir(struct hv_device *dev) 142 { 143 if (!IS_ERR(hv_debug_root)) 144 debugfs_remove_recursive(dev->debug_dir); 145 } 146 147 /* Remove all dentrys associated with vmbus testing */ 148 void hv_debug_rm_all_dir(void) 149 { 150 debugfs_remove_recursive(hv_debug_root); 151 } 152 153 /* Delay buffer/message reads on a vmbus channel */ 154 void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type) 155 { 156 struct vmbus_channel *test_channel = channel->primary_channel ? 157 channel->primary_channel : 158 channel; 159 bool state = test_channel->fuzz_testing_state; 160 161 if (state) { 162 if (delay_type == 0) 163 udelay(test_channel->fuzz_testing_interrupt_delay); 164 else 165 udelay(test_channel->fuzz_testing_message_delay); 166 } 167 } 168 169 /* Initialize top dentry for vmbus testing */ 170 int hv_debug_init(void) 171 { 172 hv_debug_root = debugfs_create_dir("hyperv", NULL); 173 if (IS_ERR(hv_debug_root)) { 174 pr_debug("debugfs_hyperv: hyperv/ not created\n"); 175 return PTR_ERR(hv_debug_root); 176 } 177 return 0; 178 } 179