arm: dts: rockchip: add mpu6050 to rk3288-evb-act8846
[firefly-linux-kernel-4.4.55.git] / fs / jbd2 / checkpoint.c
index 6bb52859cb866a12e804453c77d3f0a301fe327b..684996c8a3a4a2df646dc44c4ee4e90904470989 100644 (file)
@@ -96,15 +96,8 @@ static int __try_to_free_cp_buf(struct journal_head *jh)
 
        if (jh->b_transaction == NULL && !buffer_locked(bh) &&
            !buffer_dirty(bh) && !buffer_write_io_error(bh)) {
-               /*
-                * Get our reference so that bh cannot be freed before
-                * we unlock it
-                */
-               get_bh(bh);
                JBUFFER_TRACE(jh, "remove from checkpoint list");
                ret = __jbd2_journal_remove_checkpoint(jh) + 1;
-               BUFFER_TRACE(bh, "release");
-               __brelse(bh);
        }
        return ret;
 }
@@ -120,10 +113,8 @@ void __jbd2_log_wait_for_space(journal_t *journal)
        int nblocks, space_left;
        /* assert_spin_locked(&journal->j_state_lock); */
 
-       nblocks = jbd_space_needed(journal);
-       while (__jbd2_log_space_left(journal) < nblocks) {
-               if (journal->j_flags & JBD2_ABORT)
-                       return;
+       nblocks = jbd2_space_needed(journal);
+       while (jbd2_log_space_left(journal) < nblocks) {
                write_unlock(&journal->j_state_lock);
                mutex_lock(&journal->j_checkpoint_mutex);
 
@@ -139,9 +130,13 @@ void __jbd2_log_wait_for_space(journal_t *journal)
                 * trace for forensic evidence.
                 */
                write_lock(&journal->j_state_lock);
+               if (journal->j_flags & JBD2_ABORT) {
+                       mutex_unlock(&journal->j_checkpoint_mutex);
+                       return;
+               }
                spin_lock(&journal->j_list_lock);
-               nblocks = jbd_space_needed(journal);
-               space_left = __jbd2_log_space_left(journal);
+               nblocks = jbd2_space_needed(journal);
+               space_left = jbd2_log_space_left(journal);
                if (space_left < nblocks) {
                        int chkpt = journal->j_checkpoint_transactions != NULL;
                        tid_t tid = 0;
@@ -156,7 +151,15 @@ void __jbd2_log_wait_for_space(journal_t *journal)
                                /* We were able to recover space; yay! */
                                ;
                        } else if (tid) {
+                               /*
+                                * jbd2_journal_commit_transaction() may want
+                                * to take the checkpoint_mutex if JBD2_FLUSHED
+                                * is set.  So we need to temporarily drop it.
+                                */
+                               mutex_unlock(&journal->j_checkpoint_mutex);
                                jbd2_log_wait_commit(journal, tid);
+                               write_lock(&journal->j_state_lock);
+                               continue;
                        } else {
                                printk(KERN_ERR "%s: needed %d blocks and "
                                       "only had %d space available\n",
@@ -175,58 +178,6 @@ void __jbd2_log_wait_for_space(journal_t *journal)
        }
 }
 
-/*
- * Clean up transaction's list of buffers submitted for io.
- * We wait for any pending IO to complete and remove any clean
- * buffers. Note that we take the buffers in the opposite ordering
- * from the one in which they were submitted for IO.
- *
- * Return 0 on success, and return <0 if some buffers have failed
- * to be written out.
- *
- * Called with j_list_lock held.
- */
-static int __wait_cp_io(journal_t *journal, transaction_t *transaction)
-{
-       struct journal_head *jh;
-       struct buffer_head *bh;
-       tid_t this_tid;
-       int released = 0;
-       int ret = 0;
-
-       this_tid = transaction->t_tid;
-restart:
-       /* Did somebody clean up the transaction in the meanwhile? */
-       if (journal->j_checkpoint_transactions != transaction ||
-                       transaction->t_tid != this_tid)
-               return ret;
-       while (!released && transaction->t_checkpoint_io_list) {
-               jh = transaction->t_checkpoint_io_list;
-               bh = jh2bh(jh);
-               get_bh(bh);
-               if (buffer_locked(bh)) {
-                       spin_unlock(&journal->j_list_lock);
-                       wait_on_buffer(bh);
-                       /* the journal_head may have gone by now */
-                       BUFFER_TRACE(bh, "brelse");
-                       __brelse(bh);
-                       spin_lock(&journal->j_list_lock);
-                       goto restart;
-               }
-               if (unlikely(buffer_write_io_error(bh)))
-                       ret = -EIO;
-
-               /*
-                * Now in whatever state the buffer currently is, we know that
-                * it has been written out and so we can drop it from the list
-                */
-               released = __jbd2_journal_remove_checkpoint(jh);
-               __brelse(bh);
-       }
-
-       return ret;
-}
-
 static void
 __flush_batch(journal_t *journal, int *batch_count)
 {
@@ -246,81 +197,6 @@ __flush_batch(journal_t *journal, int *batch_count)
        *batch_count = 0;
 }
 
-/*
- * Try to flush one buffer from the checkpoint list to disk.
- *
- * Return 1 if something happened which requires us to abort the current
- * scan of the checkpoint list.  Return <0 if the buffer has failed to
- * be written out.
- *
- * Called with j_list_lock held and drops it if 1 is returned
- */
-static int __process_buffer(journal_t *journal, struct journal_head *jh,
-                           int *batch_count, transaction_t *transaction)
-{
-       struct buffer_head *bh = jh2bh(jh);
-       int ret = 0;
-
-       if (buffer_locked(bh)) {
-               get_bh(bh);
-               spin_unlock(&journal->j_list_lock);
-               wait_on_buffer(bh);
-               /* the journal_head may have gone by now */
-               BUFFER_TRACE(bh, "brelse");
-               __brelse(bh);
-               ret = 1;
-       } else if (jh->b_transaction != NULL) {
-               transaction_t *t = jh->b_transaction;
-               tid_t tid = t->t_tid;
-
-               transaction->t_chp_stats.cs_forced_to_close++;
-               spin_unlock(&journal->j_list_lock);
-               if (unlikely(journal->j_flags & JBD2_UNMOUNT))
-                       /*
-                        * The journal thread is dead; so starting and
-                        * waiting for a commit to finish will cause
-                        * us to wait for a _very_ long time.
-                        */
-                       printk(KERN_ERR "JBD2: %s: "
-                              "Waiting for Godot: block %llu\n",
-                              journal->j_devname,
-                              (unsigned long long) bh->b_blocknr);
-               jbd2_log_start_commit(journal, tid);
-               jbd2_log_wait_commit(journal, tid);
-               ret = 1;
-       } else if (!buffer_dirty(bh)) {
-               ret = 1;
-               if (unlikely(buffer_write_io_error(bh)))
-                       ret = -EIO;
-               get_bh(bh);
-               BUFFER_TRACE(bh, "remove from checkpoint");
-               __jbd2_journal_remove_checkpoint(jh);
-               spin_unlock(&journal->j_list_lock);
-               __brelse(bh);
-       } else {
-               /*
-                * Important: we are about to write the buffer, and
-                * possibly block, while still holding the journal lock.
-                * We cannot afford to let the transaction logic start
-                * messing around with this buffer before we write it to
-                * disk, as that would break recoverability.
-                */
-               BUFFER_TRACE(bh, "queue");
-               get_bh(bh);
-               J_ASSERT_BH(bh, !buffer_jwrite(bh));
-               journal->j_chkpt_bhs[*batch_count] = bh;
-               __buffer_relink_io(jh);
-               transaction->t_chp_stats.cs_written++;
-               (*batch_count)++;
-               if (*batch_count == JBD2_NR_BATCH) {
-                       spin_unlock(&journal->j_list_lock);
-                       __flush_batch(journal, batch_count);
-                       ret = 1;
-               }
-       }
-       return ret;
-}
-
 /*
  * Perform an actual checkpoint. We take the first transaction on the
  * list of transactions to be checkpointed and send all its buffers
@@ -331,9 +207,11 @@ static int __process_buffer(journal_t *journal, struct journal_head *jh,
  */
 int jbd2_log_do_checkpoint(journal_t *journal)
 {
-       transaction_t *transaction;
-       tid_t this_tid;
-       int result;
+       struct journal_head     *jh;
+       struct buffer_head      *bh;
+       transaction_t           *transaction;
+       tid_t                   this_tid;
+       int                     result, batch_count = 0;
 
        jbd_debug(1, "Start checkpoint\n");
 
@@ -366,45 +244,117 @@ restart:
         * done (maybe it's a new transaction, but it fell at the same
         * address).
         */
-       if (journal->j_checkpoint_transactions == transaction &&
-                       transaction->t_tid == this_tid) {
-               int batch_count = 0;
-               struct journal_head *jh;
-               int retry = 0, err;
-
-               while (!retry && transaction->t_checkpoint_list) {
-                       jh = transaction->t_checkpoint_list;
-                       retry = __process_buffer(journal, jh, &batch_count,
-                                                transaction);
-                       if (retry < 0 && !result)
-                               result = retry;
-                       if (!retry && (need_resched() ||
-                               spin_needbreak(&journal->j_list_lock))) {
-                               spin_unlock(&journal->j_list_lock);
-                               retry = 1;
-                               break;
-                       }
+       if (journal->j_checkpoint_transactions != transaction ||
+           transaction->t_tid != this_tid)
+               goto out;
+
+       /* checkpoint all of the transaction's buffers */
+       while (transaction->t_checkpoint_list) {
+               jh = transaction->t_checkpoint_list;
+               bh = jh2bh(jh);
+
+               if (buffer_locked(bh)) {
+                       spin_unlock(&journal->j_list_lock);
+                       get_bh(bh);
+                       wait_on_buffer(bh);
+                       /* the journal_head may have gone by now */
+                       BUFFER_TRACE(bh, "brelse");
+                       __brelse(bh);
+                       goto retry;
                }
+               if (jh->b_transaction != NULL) {
+                       transaction_t *t = jh->b_transaction;
+                       tid_t tid = t->t_tid;
 
-               if (batch_count) {
-                       if (!retry) {
-                               spin_unlock(&journal->j_list_lock);
-                               retry = 1;
-                       }
-                       __flush_batch(journal, &batch_count);
+                       transaction->t_chp_stats.cs_forced_to_close++;
+                       spin_unlock(&journal->j_list_lock);
+                       if (unlikely(journal->j_flags & JBD2_UNMOUNT))
+                               /*
+                                * The journal thread is dead; so
+                                * starting and waiting for a commit
+                                * to finish will cause us to wait for
+                                * a _very_ long time.
+                                */
+                               printk(KERN_ERR
+               "JBD2: %s: Waiting for Godot: block %llu\n",
+               journal->j_devname, (unsigned long long) bh->b_blocknr);
+
+                       jbd2_log_start_commit(journal, tid);
+                       jbd2_log_wait_commit(journal, tid);
+                       goto retry;
                }
+               if (!buffer_dirty(bh)) {
+                       if (unlikely(buffer_write_io_error(bh)) && !result)
+                               result = -EIO;
+                       BUFFER_TRACE(bh, "remove from checkpoint");
+                       if (__jbd2_journal_remove_checkpoint(jh))
+                               /* The transaction was released; we're done */
+                               goto out;
+                       continue;
+               }
+               /*
+                * Important: we are about to write the buffer, and
+                * possibly block, while still holding the journal
+                * lock.  We cannot afford to let the transaction
+                * logic start messing around with this buffer before
+                * we write it to disk, as that would break
+                * recoverability.
+                */
+               BUFFER_TRACE(bh, "queue");
+               get_bh(bh);
+               J_ASSERT_BH(bh, !buffer_jwrite(bh));
+               journal->j_chkpt_bhs[batch_count++] = bh;
+               __buffer_relink_io(jh);
+               transaction->t_chp_stats.cs_written++;
+               if ((batch_count == JBD2_NR_BATCH) ||
+                   need_resched() ||
+                   spin_needbreak(&journal->j_list_lock))
+                       goto unlock_and_flush;
+       }
 
-               if (retry) {
+       if (batch_count) {
+               unlock_and_flush:
+                       spin_unlock(&journal->j_list_lock);
+               retry:
+                       if (batch_count)
+                               __flush_batch(journal, &batch_count);
                        spin_lock(&journal->j_list_lock);
                        goto restart;
+       }
+
+       /*
+        * Now we issued all of the transaction's buffers, let's deal
+        * with the buffers that are out for I/O.
+        */
+restart2:
+       /* Did somebody clean up the transaction in the meanwhile? */
+       if (journal->j_checkpoint_transactions != transaction ||
+           transaction->t_tid != this_tid)
+               goto out;
+
+       while (transaction->t_checkpoint_io_list) {
+               jh = transaction->t_checkpoint_io_list;
+               bh = jh2bh(jh);
+               if (buffer_locked(bh)) {
+                       spin_unlock(&journal->j_list_lock);
+                       get_bh(bh);
+                       wait_on_buffer(bh);
+                       /* the journal_head may have gone by now */
+                       BUFFER_TRACE(bh, "brelse");
+                       __brelse(bh);
+                       spin_lock(&journal->j_list_lock);
+                       goto restart2;
                }
+               if (unlikely(buffer_write_io_error(bh)) && !result)
+                       result = -EIO;
+
                /*
-                * Now we have cleaned up the first transaction's checkpoint
-                * list. Let's clean up the second one
+                * Now in whatever state the buffer currently is, we
+                * know that it has been written out and so we can
+                * drop it from the list
                 */
-               err = __wait_cp_io(journal, transaction);
-               if (!result)
-                       result = err;
+               if (__jbd2_journal_remove_checkpoint(jh))
+                       break;
        }
 out:
        spin_unlock(&journal->j_list_lock);
@@ -467,20 +417,17 @@ int jbd2_cleanup_journal_tail(journal_t *journal)
  * journal_clean_one_cp_list
  *
  * Find all the written-back checkpoint buffers in the given list and
- * release them.
+ * release them. If 'destroy' is set, clean all buffers unconditionally.
  *
- * Called with the journal locked.
  * Called with j_list_lock held.
- * Returns number of buffers reaped (for debug)
+ * Returns 1 if we freed the transaction, 0 otherwise.
  */
-
-static int journal_clean_one_cp_list(struct journal_head *jh, int *released)
+static int journal_clean_one_cp_list(struct journal_head *jh, bool destroy)
 {
        struct journal_head *last_jh;
        struct journal_head *next_jh = jh;
-       int ret, freed = 0;
+       int ret;
 
-       *released = 0;
        if (!jh)
                return 0;
 
@@ -488,14 +435,14 @@ static int journal_clean_one_cp_list(struct journal_head *jh, int *released)
        do {
                jh = next_jh;
                next_jh = jh->b_cpnext;
-               ret = __try_to_free_cp_buf(jh);
-               if (ret) {
-                       freed++;
-                       if (ret == 2) {
-                               *released = 1;
-                               return freed;
-                       }
-               }
+               if (!destroy)
+                       ret = __try_to_free_cp_buf(jh);
+               else
+                       ret = __jbd2_journal_remove_checkpoint(jh) + 1;
+               if (!ret)
+                       return 0;
+               if (ret == 2)
+                       return 1;
                /*
                 * This function only frees up some memory
                 * if possible so we dont have an obligation
@@ -503,60 +450,84 @@ static int journal_clean_one_cp_list(struct journal_head *jh, int *released)
                 * requested:
                 */
                if (need_resched())
-                       return freed;
+                       return 0;
        } while (jh != last_jh);
 
-       return freed;
+       return 0;
 }
 
 /*
  * journal_clean_checkpoint_list
  *
  * Find all the written-back checkpoint buffers in the journal and release them.
+ * If 'destroy' is set, release all buffers unconditionally.
  *
- * Called with the journal locked.
  * Called with j_list_lock held.
- * Returns number of buffers reaped (for debug)
  */
-
-int __jbd2_journal_clean_checkpoint_list(journal_t *journal)
+void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy)
 {
        transaction_t *transaction, *last_transaction, *next_transaction;
-       int ret = 0;
-       int released;
+       int ret;
 
        transaction = journal->j_checkpoint_transactions;
        if (!transaction)
-               goto out;
+               return;
 
        last_transaction = transaction->t_cpprev;
        next_transaction = transaction;
        do {
                transaction = next_transaction;
                next_transaction = transaction->t_cpnext;
-               ret += journal_clean_one_cp_list(transaction->
-                               t_checkpoint_list, &released);
+               ret = journal_clean_one_cp_list(transaction->t_checkpoint_list,
+                                               destroy);
                /*
                 * This function only frees up some memory if possible so we
                 * dont have an obligation to finish processing. Bail out if
                 * preemption requested:
                 */
                if (need_resched())
-                       goto out;
-               if (released)
+                       return;
+               if (ret)
                        continue;
                /*
                 * It is essential that we are as careful as in the case of
                 * t_checkpoint_list with removing the buffer from the list as
                 * we can possibly see not yet submitted buffers on io_list
                 */
-               ret += journal_clean_one_cp_list(transaction->
-                               t_checkpoint_io_list, &released);
+               ret = journal_clean_one_cp_list(transaction->
+                               t_checkpoint_io_list, destroy);
                if (need_resched())
-                       goto out;
+                       return;
+               /*
+                * Stop scanning if we couldn't free the transaction. This
+                * avoids pointless scanning of transactions which still
+                * weren't checkpointed.
+                */
+               if (!ret)
+                       return;
        } while (transaction != last_transaction);
-out:
-       return ret;
+}
+
+/*
+ * Remove buffers from all checkpoint lists as journal is aborted and we just
+ * need to free memory
+ */
+void jbd2_journal_destroy_checkpoint(journal_t *journal)
+{
+       /*
+        * We loop because __jbd2_journal_clean_checkpoint_list() may abort
+        * early due to a need of rescheduling.
+        */
+       while (1) {
+               spin_lock(&journal->j_list_lock);
+               if (!journal->j_checkpoint_transactions) {
+                       spin_unlock(&journal->j_list_lock);
+                       break;
+               }
+               __jbd2_journal_clean_checkpoint_list(journal, true);
+               spin_unlock(&journal->j_list_lock);
+               cond_resched();
+       }
 }
 
 /*
@@ -624,10 +595,6 @@ int __jbd2_journal_remove_checkpoint(struct journal_head *jh)
 
        __jbd2_journal_drop_transaction(journal, transaction);
        jbd2_journal_free_transaction(transaction);
-
-       /* Just in case anybody was waiting for more transactions to be
-           checkpointed... */
-       wake_up(&journal->j_wait_logspace);
        ret = 1;
 out:
        return ret;
@@ -689,9 +656,7 @@ void __jbd2_journal_drop_transaction(journal_t *journal, transaction_t *transact
        J_ASSERT(transaction->t_state == T_FINISHED);
        J_ASSERT(transaction->t_buffers == NULL);
        J_ASSERT(transaction->t_forget == NULL);
-       J_ASSERT(transaction->t_iobuf_list == NULL);
        J_ASSERT(transaction->t_shadow_list == NULL);
-       J_ASSERT(transaction->t_log_list == NULL);
        J_ASSERT(transaction->t_checkpoint_list == NULL);
        J_ASSERT(transaction->t_checkpoint_io_list == NULL);
        J_ASSERT(atomic_read(&transaction->t_updates) == 0);