* various local functions of those subsystems.
*/
-#define UBIFS_DBG_PRESERVE_UBI
-
-#include "ubifs.h"
#include <linux/module.h>
#include <linux/debugfs.h>
#include <linux/math64.h>
#include <linux/uaccess.h>
+#include <linux/random.h>
+#include "ubifs.h"
#ifdef CONFIG_UBIFS_FS_DEBUG
return 0;
}
-/* Failure mode for recovery testing */
-
-#define chance(n, d) (simple_rand() <= (n) * 32768LL / (d))
-
-struct failure_mode_info {
- struct list_head list;
- struct ubifs_info *c;
-};
-
-static LIST_HEAD(fmi_list);
-static DEFINE_SPINLOCK(fmi_lock);
-
-static unsigned int next;
-
-static int simple_rand(void)
-{
- if (next == 0)
- next = current->pid;
- next = next * 1103515245 + 12345;
- return (next >> 16) & 32767;
-}
-
-static void failure_mode_init(struct ubifs_info *c)
-{
- struct failure_mode_info *fmi;
-
- fmi = kmalloc(sizeof(struct failure_mode_info), GFP_NOFS);
- if (!fmi) {
- ubifs_err("Failed to register failure mode - no memory");
- return;
- }
- fmi->c = c;
- spin_lock(&fmi_lock);
- list_add_tail(&fmi->list, &fmi_list);
- spin_unlock(&fmi_lock);
-}
-
-static void failure_mode_exit(struct ubifs_info *c)
+static inline int chance(unsigned int n, unsigned int out_of)
{
- struct failure_mode_info *fmi, *tmp;
+ return !!((random32() % out_of) + 1 <= n);
- spin_lock(&fmi_lock);
- list_for_each_entry_safe(fmi, tmp, &fmi_list, list)
- if (fmi->c == c) {
- list_del(&fmi->list);
- kfree(fmi);
- }
- spin_unlock(&fmi_lock);
-}
-
-static struct ubifs_info *dbg_find_info(struct ubi_volume_desc *desc)
-{
- struct failure_mode_info *fmi;
-
- spin_lock(&fmi_lock);
- list_for_each_entry(fmi, &fmi_list, list)
- if (fmi->c->ubi == desc) {
- struct ubifs_info *c = fmi->c;
-
- spin_unlock(&fmi_lock);
- return c;
- }
- spin_unlock(&fmi_lock);
- return NULL;
}
-static int in_failure_mode(struct ubi_volume_desc *desc)
+static int power_cut_emulated(struct ubifs_info *c, int lnum, int write)
{
- struct ubifs_info *c = dbg_find_info(desc);
+ struct ubifs_debug_info *d = c->dbg;
- if (c && dbg_is_tst_rcvry(c))
- return c->dbg->failure_mode;
- return 0;
-}
+ ubifs_assert(dbg_is_tst_rcvry(c));
-static int do_fail(struct ubi_volume_desc *desc, int lnum, int write)
-{
- struct ubifs_info *c = dbg_find_info(desc);
- struct ubifs_debug_info *d;
-
- if (!c || !dbg_is_tst_rcvry(c))
- return 0;
- d = c->dbg;
- if (d->failure_mode)
- return 1;
- if (!d->fail_cnt) {
- /* First call - decide delay to failure */
+ if (!d->pc_cnt) {
+ /* First call - decide delay to the power cut */
if (chance(1, 2)) {
- unsigned int delay = 1 << (simple_rand() >> 11);
+ unsigned long delay;
if (chance(1, 2)) {
- d->fail_delay = 1;
- d->fail_timeout = jiffies +
- msecs_to_jiffies(delay);
- ubifs_warn("failing after %ums", delay);
+ d->pc_delay = 1;
+ /* Fail withing 1 minute */
+ delay = random32() % 60000;
+ d->pc_timeout = jiffies;
+ d->pc_timeout += msecs_to_jiffies(delay);
+ ubifs_warn("failing after %lums", delay);
} else {
- d->fail_delay = 2;
- d->fail_cnt_max = delay;
- ubifs_warn("failing after %u calls", delay);
+ d->pc_delay = 2;
+ delay = random32() % 10000;
+ /* Fail within 10000 operations */
+ d->pc_cnt_max = delay;
+ ubifs_warn("failing after %lu calls", delay);
}
}
- d->fail_cnt += 1;
+
+ d->pc_cnt += 1;
}
+
/* Determine if failure delay has expired */
- if (d->fail_delay == 1) {
- if (time_before(jiffies, d->fail_timeout))
+ if (d->pc_delay == 1 && time_before(jiffies, d->pc_timeout))
return 0;
- } else if (d->fail_delay == 2)
- if (d->fail_cnt++ < d->fail_cnt_max)
+ if (d->pc_delay == 2 && d->pc_cnt++ < d->pc_cnt_max)
return 0;
+
if (lnum == UBIFS_SB_LNUM) {
- if (write) {
- if (chance(1, 2))
- return 0;
- } else if (chance(19, 20))
+ if (write && chance(1, 2))
+ return 0;
+ if (chance(19, 20))
return 0;
ubifs_warn("failing in super block LEB %d", lnum);
} else if (lnum == UBIFS_MST_LNUM || lnum == UBIFS_MST_LNUM + 1) {
return 0;
ubifs_warn("failing in master LEB %d", lnum);
} else if (lnum >= UBIFS_LOG_LNUM && lnum <= c->log_last) {
- if (write) {
- if (chance(99, 100))
- return 0;
- } else if (chance(399, 400))
+ if (write && chance(99, 100))
+ return 0;
+ if (chance(399, 400))
return 0;
ubifs_warn("failing in log LEB %d", lnum);
} else if (lnum >= c->lpt_first && lnum <= c->lpt_last) {
- if (write) {
- if (chance(7, 8))
- return 0;
- } else if (chance(19, 20))
+ if (write && chance(7, 8))
+ return 0;
+ if (chance(19, 20))
return 0;
ubifs_warn("failing in LPT LEB %d", lnum);
} else if (lnum >= c->orph_first && lnum <= c->orph_last) {
- if (write) {
- if (chance(1, 2))
- return 0;
- } else if (chance(9, 10))
+ if (write && chance(1, 2))
+ return 0;
+ if (chance(9, 10))
return 0;
ubifs_warn("failing in orphan LEB %d", lnum);
} else if (lnum == c->ihead_lnum) {
ubifs_warn("failing in bud LEB %d commit not running", lnum);
}
- d->failure_mode = 1;
+ d->pc_happened = 1;
+ ubifs_warn("========== Power cut emulated ==========");
dump_stack();
return 1;
}
-static void cut_data(const void *buf, int len)
+static void cut_data(const void *buf, unsigned int len)
{
- int flen, i;
+ unsigned int from, to, i, ffs = chance(1, 2);
unsigned char *p = (void *)buf;
- flen = (len * (long long)simple_rand()) >> 15;
- for (i = flen; i < len; i++)
- p[i] = 0xff;
+ from = random32() % (len + 1);
+ if (chance(1, 2))
+ to = random32() % (len - from + 1);
+ else
+ to = len;
+
+ if (from < to)
+ ubifs_warn("filled bytes %u-%u with %s", from, to - 1,
+ ffs ? "0xFFs" : "random data");
+
+ if (ffs)
+ for (i = from; i < to; i++)
+ p[i] = 0xFF;
+ else
+ for (i = from; i < to; i++)
+ p[i] = random32() % 0x100;
}
-int dbg_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf,
+int dbg_leb_write(struct ubifs_info *c, int lnum, const void *buf,
int offs, int len, int dtype)
{
int err, failing;
- if (in_failure_mode(desc))
+ if (c->dbg->pc_happened)
return -EROFS;
- failing = do_fail(desc, lnum, 1);
+
+ failing = power_cut_emulated(c, lnum, 1);
if (failing)
cut_data(buf, len);
- err = ubi_leb_write(desc, lnum, buf, offs, len, dtype);
+ err = ubi_leb_write(c->ubi, lnum, buf, offs, len, dtype);
if (err)
return err;
if (failing)
return 0;
}
-int dbg_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf,
+int dbg_leb_change(struct ubifs_info *c, int lnum, const void *buf,
int len, int dtype)
{
int err;
- if (do_fail(desc, lnum, 1))
+ if (c->dbg->pc_happened)
return -EROFS;
- err = ubi_leb_change(desc, lnum, buf, len, dtype);
+ if (power_cut_emulated(c, lnum, 1))
+ return -EROFS;
+ err = ubi_leb_change(c->ubi, lnum, buf, len, dtype);
if (err)
return err;
- if (do_fail(desc, lnum, 1))
+ if (power_cut_emulated(c, lnum, 1))
return -EROFS;
return 0;
}
-int dbg_leb_unmap(struct ubi_volume_desc *desc, int lnum)
+int dbg_leb_unmap(struct ubifs_info *c, int lnum)
{
int err;
- if (do_fail(desc, lnum, 0))
+ if (c->dbg->pc_happened)
+ return -EROFS;
+ if (power_cut_emulated(c, lnum, 0))
return -EROFS;
- err = ubi_leb_unmap(desc, lnum);
+ err = ubi_leb_unmap(c->ubi, lnum);
if (err)
return err;
- if (do_fail(desc, lnum, 0))
+ if (power_cut_emulated(c, lnum, 0))
return -EROFS;
return 0;
}
-int dbg_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype)
+int dbg_leb_map(struct ubifs_info *c, int lnum, int dtype)
{
int err;
- if (do_fail(desc, lnum, 0))
+ if (c->dbg->pc_happened)
+ return -EROFS;
+ if (power_cut_emulated(c, lnum, 0))
return -EROFS;
- err = ubi_leb_map(desc, lnum, dtype);
+ err = ubi_leb_map(c->ubi, lnum, dtype);
if (err)
return err;
- if (do_fail(desc, lnum, 0))
+ if (power_cut_emulated(c, lnum, 0))
return -EROFS;
return 0;
}
if (!c->dbg)
return -ENOMEM;
- failure_mode_init(c);
return 0;
}
*/
void ubifs_debugging_exit(struct ubifs_info *c)
{
- failure_mode_exit(c);
kfree(c->dbg);
}