1 files changed, 291 insertions, 36 deletions

diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 510ffa0bbda4..e975bd82f38b 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -32,6 +32,8 @@
 #include "ubifs.h"
 #include <linux/module.h>
 #include <linux/moduleparam.h>
+#include <linux/debugfs.h>
+#include <linux/math64.h>
 
 #ifdef CONFIG_UBIFS_FS_DEBUG
 
@@ -596,7 +598,9 @@ void dbg_dump_budg(struct ubifs_info *c)
         struct rb_node *rb;
         struct ubifs_bud *bud;
         struct ubifs_gced_idx_leb *idx_gc;
+        long long available, outstanding, free;
 
+        ubifs_assert(spin_is_locked(&c->space_lock));
         spin_lock(&dbg_lock);
         printk(KERN_DEBUG "(pid %d) Budgeting info: budg_data_growth %lld, "
                "budg_dd_growth %lld, budg_idx_growth %lld\n", current->pid,
@@ -616,9 +620,11 @@ void dbg_dump_budg(struct ubifs_info *c)
                c->dark_wm, c->dead_wm, c->max_idx_node_sz);
         printk(KERN_DEBUG "\tgc_lnum %d, ihead_lnum %d\n",
                c->gc_lnum, c->ihead_lnum);
-        for (i = 0; i < c->jhead_cnt; i++)
-                printk(KERN_DEBUG "\tjhead %d\t LEB %d\n",
-                       c->jheads[i].wbuf.jhead, c->jheads[i].wbuf.lnum);
+        /* If we are in R/O mode, journal heads do not exist */
+        if (c->jheads)
+                for (i = 0; i < c->jhead_cnt; i++)
+                        printk(KERN_DEBUG "\tjhead %d\t LEB %d\n",
+                               c->jheads[i].wbuf.jhead, c->jheads[i].wbuf.lnum);
         for (rb = rb_first(&c->buds); rb; rb = rb_next(rb)) {
                 bud = rb_entry(rb, struct ubifs_bud, rb);
                 printk(KERN_DEBUG "\tbud LEB %d\n", bud->lnum);
@@ -629,6 +635,14 @@ void dbg_dump_budg(struct ubifs_info *c)
                 printk(KERN_DEBUG "\tGC'ed idx LEB %d unmap %d\n",
                        idx_gc->lnum, idx_gc->unmap);
         printk(KERN_DEBUG "\tcommit state %d\n", c->cmt_state);
+
+        /* Print budgeting predictions */
+        available = ubifs_calc_available(c, c->min_idx_lebs);
+        outstanding = c->budg_data_growth + c->budg_dd_growth;
+        free = ubifs_get_free_space_nolock(c);
+        printk(KERN_DEBUG "Budgeting predictions:\n");
+        printk(KERN_DEBUG "\tavailable: %lld, outstanding %lld, free %lld\n",
+               available, outstanding, free);
         spin_unlock(&dbg_lock);
 }
 
@@ -645,7 +659,8 @@ void dbg_dump_lprops(struct ubifs_info *c)
         struct ubifs_lprops lp;
         struct ubifs_lp_stats lst;
 
-        printk(KERN_DEBUG "(pid %d) Dumping LEB properties\n", current->pid);
+        printk(KERN_DEBUG "(pid %d) start dumping LEB properties\n",
+               current->pid);
         ubifs_get_lp_stats(c, &lst);
         dbg_dump_lstats(&lst);
 
@@ -656,6 +671,8 @@ void dbg_dump_lprops(struct ubifs_info *c)
 
                 dbg_dump_lprop(c, &lp);
         }
+        printk(KERN_DEBUG "(pid %d) finish dumping LEB properties\n",
+               current->pid);
 }
 
 void dbg_dump_lpt_info(struct ubifs_info *c)
@@ -663,6 +680,7 @@ void dbg_dump_lpt_info(struct ubifs_info *c)
         int i;
 
         spin_lock(&dbg_lock);
+        printk(KERN_DEBUG "(pid %d) dumping LPT information\n", current->pid);
         printk(KERN_DEBUG "\tlpt_sz:        %lld\n", c->lpt_sz);
         printk(KERN_DEBUG "\tpnode_sz:      %d\n", c->pnode_sz);
         printk(KERN_DEBUG "\tnnode_sz:      %d\n", c->nnode_sz);
@@ -684,7 +702,8 @@ void dbg_dump_lpt_info(struct ubifs_info *c)
         printk(KERN_DEBUG "\tLPT root is at %d:%d\n", c->lpt_lnum, c->lpt_offs);
         printk(KERN_DEBUG "\tLPT head is at %d:%d\n",
                c->nhead_lnum, c->nhead_offs);
-        printk(KERN_DEBUG "\tLPT ltab is at %d:%d\n", c->ltab_lnum, c->ltab_offs);
+        printk(KERN_DEBUG "\tLPT ltab is at %d:%d\n",
+               c->ltab_lnum, c->ltab_offs);
         if (c->big_lpt)
                 printk(KERN_DEBUG "\tLPT lsave is at %d:%d\n",
                        c->lsave_lnum, c->lsave_offs);
@@ -703,9 +722,9 @@ void dbg_dump_leb(const struct ubifs_info *c, int lnum)
         if (dbg_failure_mode)
                 return;
 
-        printk(KERN_DEBUG "(pid %d) Dumping LEB %d\n", current->pid, lnum);
-
-        sleb = ubifs_scan(c, lnum, 0, c->dbg_buf);
+        printk(KERN_DEBUG "(pid %d) start dumping LEB %d\n",
+               current->pid, lnum);
+        sleb = ubifs_scan(c, lnum, 0, c->dbg->buf);
         if (IS_ERR(sleb)) {
                 ubifs_err("scan error %d", (int)PTR_ERR(sleb));
                 return;
@@ -721,6 +740,8 @@ void dbg_dump_leb(const struct ubifs_info *c, int lnum)
                 dbg_dump_node(c, snod->node);
         }
 
+        printk(KERN_DEBUG "(pid %d) finish dumping LEB %d\n",
+               current->pid, lnum);
         ubifs_scan_destroy(sleb);
         return;
 }
@@ -768,7 +789,7 @@ void dbg_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat)
 {
         int i;
 
-        printk(KERN_DEBUG "(pid %d) Dumping heap cat %d (%d elements)\n",
+        printk(KERN_DEBUG "(pid %d) start dumping heap cat %d (%d elements)\n",
                current->pid, cat, heap->cnt);
         for (i = 0; i < heap->cnt; i++) {
                 struct ubifs_lprops *lprops = heap->arr[i];
@@ -777,6 +798,7 @@ void dbg_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat)
                        "flags %d\n", i, lprops->lnum, lprops->hpos,
                        lprops->free, lprops->dirty, lprops->flags);
         }
+        printk(KERN_DEBUG "(pid %d) finish dumping heap\n", current->pid);
 }
 
 void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
@@ -784,7 +806,7 @@ void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
 {
         int i;
 
-        printk(KERN_DEBUG "(pid %d) Dumping pnode:\n", current->pid);
+        printk(KERN_DEBUG "(pid %d) dumping pnode:\n", current->pid);
         printk(KERN_DEBUG "\taddress %zx parent %zx cnext %zx\n",
                (size_t)pnode, (size_t)parent, (size_t)pnode->cnext);
         printk(KERN_DEBUG "\tflags %lu iip %d level %d num %d\n",
@@ -803,7 +825,7 @@ void dbg_dump_tnc(struct ubifs_info *c)
         int level;
 
         printk(KERN_DEBUG "\n");
-        printk(KERN_DEBUG "(pid %d) Dumping the TNC tree\n", current->pid);
+        printk(KERN_DEBUG "(pid %d) start dumping TNC tree\n", current->pid);
         znode = ubifs_tnc_levelorder_next(c->zroot.znode, NULL);
         level = znode->level;
         printk(KERN_DEBUG "== Level %d ==\n", level);
@@ -815,8 +837,7 @@ void dbg_dump_tnc(struct ubifs_info *c)
                 dbg_dump_znode(c, znode);
                 znode = ubifs_tnc_levelorder_next(c->zroot.znode, znode);
         }
-
-        printk(KERN_DEBUG "\n");
+        printk(KERN_DEBUG "(pid %d) finish dumping TNC tree\n", current->pid);
 }
 
 static int dump_znode(struct ubifs_info *c, struct ubifs_znode *znode,
@@ -839,6 +860,65 @@ void dbg_dump_index(struct ubifs_info *c)
 }
 
 /**
+ * dbg_save_space_info - save information about flash space.
+ * @c: UBIFS file-system description object
+ *
+ * This function saves information about UBIFS free space, dirty space, etc, in
+ * order to check it later.
+ */
+void dbg_save_space_info(struct ubifs_info *c)
+{
+        struct ubifs_debug_info *d = c->dbg;
+
+        ubifs_get_lp_stats(c, &d->saved_lst);
+
+        spin_lock(&c->space_lock);
+        d->saved_free = ubifs_get_free_space_nolock(c);
+        spin_unlock(&c->space_lock);
+}
+
+/**
+ * dbg_check_space_info - check flash space information.
+ * @c: UBIFS file-system description object
+ *
+ * This function compares current flash space information with the information
+ * which was saved when the 'dbg_save_space_info()' function was called.
+ * Returns zero if the information has not changed, and %-EINVAL it it has
+ * changed.
+ */
+int dbg_check_space_info(struct ubifs_info *c)
+{
+        struct ubifs_debug_info *d = c->dbg;
+        struct ubifs_lp_stats lst;
+        long long avail, free;
+
+        spin_lock(&c->space_lock);
+        avail = ubifs_calc_available(c, c->min_idx_lebs);
+        spin_unlock(&c->space_lock);
+        free = ubifs_get_free_space(c);
+
+        if (free != d->saved_free) {
+                ubifs_err("free space changed from %lld to %lld",
+                          d->saved_free, free);
+                goto out;
+        }
+
+        return 0;
+
+out:
+        ubifs_msg("saved lprops statistics dump");
+        dbg_dump_lstats(&d->saved_lst);
+        ubifs_get_lp_stats(c, &lst);
+        ubifs_msg("current lprops statistics dump");
+        dbg_dump_lstats(&d->saved_lst);
+        spin_lock(&c->space_lock);
+        dbg_dump_budg(c);
+        spin_unlock(&c->space_lock);
+        dump_stack();
+        return -EINVAL;
+}
+
+/**
  * dbg_check_synced_i_size - check synchronized inode size.
  * @inode: inode to check
  *
@@ -992,8 +1072,8 @@ static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
                         zbr1->offs, DBGKEY(&key));
                 dbg_err("but it should have key %s according to tnc",
                         DBGKEY(&zbr1->key));
-                        dbg_dump_node(c, dent1);
-                        goto out_free;
+                dbg_dump_node(c, dent1);
+                goto out_free;
         }
 
         key_read(c, &dent2->key, &key);
@@ -1002,8 +1082,8 @@ static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
                         zbr1->offs, DBGKEY(&key));
                 dbg_err("but it should have key %s according to tnc",
                         DBGKEY(&zbr2->key));
-                        dbg_dump_node(c, dent2);
-                        goto out_free;
+                dbg_dump_node(c, dent2);
+                goto out_free;
         }
 
         nlen1 = le16_to_cpu(dent1->nlen);
@@ -1020,9 +1100,9 @@ static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
                 dbg_err("bad order of colliding key %s",
                         DBGKEY(&key));
 
-        dbg_msg("first node at %d:%d\n", zbr1->lnum, zbr1->offs);
+        ubifs_msg("first node at %d:%d\n", zbr1->lnum, zbr1->offs);
         dbg_dump_node(c, dent1);
-        dbg_msg("second node at %d:%d\n", zbr2->lnum, zbr2->offs);
+        ubifs_msg("second node at %d:%d\n", zbr2->lnum, zbr2->offs);
         dbg_dump_node(c, dent2);
 
 out_free:
@@ -1327,7 +1407,7 @@ int dbg_check_tnc(struct ubifs_info *c, int extra)
  * @c: UBIFS file-system description object
  * @leaf_cb: called for each leaf node
  * @znode_cb: called for each indexing node
- * @priv: private date which is passed to callbacks
+ * @priv: private data which is passed to callbacks
  *
  * This function walks the UBIFS index and calls the @leaf_cb for each leaf
  * node and @znode_cb for each indexing node. Returns zero in case of success
@@ -2097,13 +2177,13 @@ static int simple_rand(void)
         return (next >> 16) & 32767;
 }
 
-void dbg_failure_mode_registration(struct ubifs_info *c)
+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) {
-                dbg_err("Failed to register failure mode - no memory");
+                ubifs_err("Failed to register failure mode - no memory");
                 return;
         }
         fmi->c = c;
@@ -2112,7 +2192,7 @@ void dbg_failure_mode_registration(struct ubifs_info *c)
         spin_unlock(&fmi_lock);
 }
 
-void dbg_failure_mode_deregistration(struct ubifs_info *c)
+static void failure_mode_exit(struct ubifs_info *c)
 {
         struct failure_mode_info *fmi, *tmp;
 
@@ -2146,42 +2226,44 @@ static int in_failure_mode(struct ubi_volume_desc *desc)
         struct ubifs_info *c = dbg_find_info(desc);
 
         if (c && dbg_failure_mode)
-                return c->failure_mode;
+                return c->dbg->failure_mode;
         return 0;
 }
 
 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_failure_mode)
                 return 0;
-        if (c->failure_mode)
+        d = c->dbg;
+        if (d->failure_mode)
                 return 1;
-        if (!c->fail_cnt) {
+        if (!d->fail_cnt) {
                 /* First call - decide delay to failure */
                 if (chance(1, 2)) {
                         unsigned int delay = 1 << (simple_rand() >> 11);
 
                         if (chance(1, 2)) {
-                                c->fail_delay = 1;
-                                c->fail_timeout = jiffies +
+                                d->fail_delay = 1;
+                                d->fail_timeout = jiffies +
                                                   msecs_to_jiffies(delay);
                                 dbg_rcvry("failing after %ums", delay);
                         } else {
-                                c->fail_delay = 2;
-                                c->fail_cnt_max = delay;
+                                d->fail_delay = 2;
+                                d->fail_cnt_max = delay;
                                 dbg_rcvry("failing after %u calls", delay);
                         }
                 }
-                c->fail_cnt += 1;
+                d->fail_cnt += 1;
         }
         /* Determine if failure delay has expired */
-        if (c->fail_delay == 1) {
-                if (time_before(jiffies, c->fail_timeout))
+        if (d->fail_delay == 1) {
+                if (time_before(jiffies, d->fail_timeout))
                         return 0;
-        } else if (c->fail_delay == 2)
-                if (c->fail_cnt++ < c->fail_cnt_max)
+        } else if (d->fail_delay == 2)
+                if (d->fail_cnt++ < d->fail_cnt_max)
                         return 0;
         if (lnum == UBIFS_SB_LNUM) {
                 if (write) {
@@ -2239,7 +2321,7 @@ static int do_fail(struct ubi_volume_desc *desc, int lnum, int write)
                 dbg_rcvry("failing in bud LEB %d commit not running", lnum);
         }
         ubifs_err("*** SETTING FAILURE MODE ON (LEB %d) ***", lnum);
-        c->failure_mode = 1;
+        d->failure_mode = 1;
         dump_stack();
         return 1;
 }
@@ -2344,4 +2426,177 @@ int dbg_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype)
         return 0;
 }
 
+/**
+ * ubifs_debugging_init - initialize UBIFS debugging.
+ * @c: UBIFS file-system description object
+ *
+ * This function initializes debugging-related data for the file system.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_debugging_init(struct ubifs_info *c)
+{
+        c->dbg = kzalloc(sizeof(struct ubifs_debug_info), GFP_KERNEL);
+        if (!c->dbg)
+                return -ENOMEM;
+
+        c->dbg->buf = vmalloc(c->leb_size);
+        if (!c->dbg->buf)
+                goto out;
+
+        failure_mode_init(c);
+        return 0;
+
+out:
+        kfree(c->dbg);
+        return -ENOMEM;
+}
+
+/**
+ * ubifs_debugging_exit - free debugging data.
+ * @c: UBIFS file-system description object
+ */
+void ubifs_debugging_exit(struct ubifs_info *c)
+{
+        failure_mode_exit(c);
+        vfree(c->dbg->buf);
+        kfree(c->dbg);
+}
+
+/*
+ * Root directory for UBIFS stuff in debugfs. Contains sub-directories which
+ * contain the stuff specific to particular file-system mounts.
+ */
+static struct dentry *dfs_rootdir;
+
+/**
+ * dbg_debugfs_init - initialize debugfs file-system.
+ *
+ * UBIFS uses debugfs file-system to expose various debugging knobs to
+ * user-space. This function creates "ubifs" directory in the debugfs
+ * file-system. Returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+int dbg_debugfs_init(void)
+{
+        dfs_rootdir = debugfs_create_dir("ubifs", NULL);
+        if (IS_ERR(dfs_rootdir)) {
+                int err = PTR_ERR(dfs_rootdir);
+                ubifs_err("cannot create \"ubifs\" debugfs directory, "
+                          "error %d\n", err);
+                return err;
+        }
+
+        return 0;
+}
+
+/**
+ * dbg_debugfs_exit - remove the "ubifs" directory from debugfs file-system.
+ */
+void dbg_debugfs_exit(void)
+{
+        debugfs_remove(dfs_rootdir);
+}
+
+static int open_debugfs_file(struct inode *inode, struct file *file)
+{
+        file->private_data = inode->i_private;
+        return 0;
+}
+
+static ssize_t write_debugfs_file(struct file *file, const char __user *buf,
+                                  size_t count, loff_t *ppos)
+{
+        struct ubifs_info *c = file->private_data;
+        struct ubifs_debug_info *d = c->dbg;
+
+        if (file->f_path.dentry == d->dfs_dump_lprops)
+                dbg_dump_lprops(c);
+        else if (file->f_path.dentry == d->dfs_dump_budg) {
+                spin_lock(&c->space_lock);
+                dbg_dump_budg(c);
+                spin_unlock(&c->space_lock);
+        } else if (file->f_path.dentry == d->dfs_dump_tnc) {
+                mutex_lock(&c->tnc_mutex);
+                dbg_dump_tnc(c);
+                mutex_unlock(&c->tnc_mutex);
+        } else
+                return -EINVAL;
+
+        *ppos += count;
+        return count;
+}
+
+static const struct file_operations dfs_fops = {
+        .open = open_debugfs_file,
+        .write = write_debugfs_file,
+        .owner = THIS_MODULE,
+};
+
+/**
+ * dbg_debugfs_init_fs - initialize debugfs for UBIFS instance.
+ * @c: UBIFS file-system description object
+ *
+ * This function creates all debugfs files for this instance of UBIFS. Returns
+ * zero in case of success and a negative error code in case of failure.
+ *
+ * Note, the only reason we have not merged this function with the
+ * 'ubifs_debugging_init()' function is because it is better to initialize
+ * debugfs interfaces at the very end of the mount process, and remove them at
+ * the very beginning of the mount process.
+ */
+int dbg_debugfs_init_fs(struct ubifs_info *c)
+{
+        int err;
+        const char *fname;
+        struct dentry *dent;
+        struct ubifs_debug_info *d = c->dbg;
+
+        sprintf(d->dfs_dir_name, "ubi%d_%d", c->vi.ubi_num, c->vi.vol_id);
+        d->dfs_dir = debugfs_create_dir(d->dfs_dir_name, dfs_rootdir);
+        if (IS_ERR(d->dfs_dir)) {
+                err = PTR_ERR(d->dfs_dir);
+                ubifs_err("cannot create \"%s\" debugfs directory, error %d\n",
+                          d->dfs_dir_name, err);
+                goto out;
+        }
+
+        fname = "dump_lprops";
+        dent = debugfs_create_file(fname, S_IWUGO, d->dfs_dir, c, &dfs_fops);
+        if (IS_ERR(dent))
+                goto out_remove;
+        d->dfs_dump_lprops = dent;
+
+        fname = "dump_budg";
+        dent = debugfs_create_file(fname, S_IWUGO, d->dfs_dir, c, &dfs_fops);
+        if (IS_ERR(dent))
+                goto out_remove;
+        d->dfs_dump_budg = dent;
+
+        fname = "dump_tnc";
+        dent = debugfs_create_file(fname, S_IWUGO, d->dfs_dir, c, &dfs_fops);
+        if (IS_ERR(dent))
+                goto out_remove;
+        d->dfs_dump_tnc = dent;
+
+        return 0;
+
+out_remove:
+        err = PTR_ERR(dent);
+        ubifs_err("cannot create \"%s\" debugfs directory, error %d\n",
+                  fname, err);
+        debugfs_remove_recursive(d->dfs_dir);
+out:
+        return err;
+}
+
+/**
+ * dbg_debugfs_exit_fs - remove all debugfs files.
+ * @c: UBIFS file-system description object
+ */
+void dbg_debugfs_exit_fs(struct ubifs_info *c)
+{
+        debugfs_remove_recursive(c->dbg->dfs_dir);
+}
+
 #endif /* CONFIG_UBIFS_FS_DEBUG */