[PATCH] md: improve handing of read errors with raid6 (d69762e9) · Commits · 戴 / test

drivers/md/raid6main.c

+66 −4

Original line number	Diff line number	Diff line
		@@ -420,9 +420,35 @@ static int raid6_end_read_request (struct bio * bi, unsigned int bytes_done,
		#else
		set_bit(R5_UPTODATE, &sh->dev[i].flags);
		#endif
		if (test_bit(R5_ReadError, &sh->dev[i].flags)) {
		printk(KERN_INFO "raid6: read error corrected!!\n");
		clear_bit(R5_ReadError, &sh->dev[i].flags);
		clear_bit(R5_ReWrite, &sh->dev[i].flags);
		}
		if (atomic_read(&conf->disks[i].rdev->read_errors))
		atomic_set(&conf->disks[i].rdev->read_errors, 0);
		} else {
		md_error(conf->mddev, conf->disks[i].rdev);
		int retry = 0;
		clear_bit(R5_UPTODATE, &sh->dev[i].flags);
		atomic_inc(&conf->disks[i].rdev->read_errors);
		if (conf->mddev->degraded)
		printk(KERN_WARNING "raid6: read error not correctable.\n");
		else if (test_bit(R5_ReWrite, &sh->dev[i].flags))
		/* Oh, no!!! */
		printk(KERN_WARNING "raid6: read error NOT corrected!!\n");
		else if (atomic_read(&conf->disks[i].rdev->read_errors)
		> conf->max_nr_stripes)
		printk(KERN_WARNING
		"raid6: Too many read errors, failing device.\n");
		else
		retry = 1;
		if (retry)
		set_bit(R5_ReadError, &sh->dev[i].flags);
		else {
		clear_bit(R5_ReadError, &sh->dev[i].flags);
		clear_bit(R5_ReWrite, &sh->dev[i].flags);
		md_error(conf->mddev, conf->disks[i].rdev);
		}
		}
		rdev_dec_pending(conf->disks[i].rdev, conf->mddev);
		#if 0
		@@ -1079,6 +1105,12 @@ static void handle_stripe(struct stripe_head sh, struct page tmp_page)
		if (dev->written) written++;
		rdev = conf->disks[i].rdev; /* FIXME, should I be looking rdev */
		if (!rdev \|\| !test_bit(In_sync, &rdev->flags)) {
		/* The ReadError flag will just be confusing now */
		clear_bit(R5_ReadError, &dev->flags);
		clear_bit(R5_ReWrite, &dev->flags);
		}
		if (!rdev \|\| !test_bit(In_sync, &rdev->flags)
		\|\| test_bit(R5_ReadError, &dev->flags)) {
		if ( failed < 2 )
		failed_num[failed] = i;
		failed++;
		@@ -1095,6 +1127,14 @@ static void handle_stripe(struct stripe_head sh, struct page tmp_page)
		if (failed > 2 && to_read+to_write+written) {
		for (i=disks; i--; ) {
		int bitmap_end = 0;

		if (test_bit(R5_ReadError, &sh->dev[i].flags)) {
		mdk_rdev_t *rdev = conf->disks[i].rdev;
		if (rdev && test_bit(In_sync, &rdev->flags))
		/* multiple read failures in one stripe */
		md_error(conf->mddev, rdev);
		}

		spin_lock_irq(&conf->device_lock);
		/* fail all writes first */
		bi = sh->dev[i].towrite;
		@@ -1130,7 +1170,8 @@ static void handle_stripe(struct stripe_head sh, struct page tmp_page)
		}

		/* fail any reads if this device is non-operational */
		if (!test_bit(R5_Insync, &sh->dev[i].flags)) {
		if (!test_bit(R5_Insync, &sh->dev[i].flags) \|\|
		test_bit(R5_ReadError, &sh->dev[i].flags)) {
		bi = sh->dev[i].toread;
		sh->dev[i].toread = NULL;
		if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
		@@ -1457,6 +1498,27 @@ static void handle_stripe(struct stripe_head sh, struct page tmp_page)
		clear_bit(STRIPE_SYNCING, &sh->state);
		}

		/* If the failed drives are just a ReadError, then we might need
		* to progress the repair/check process
		*/
		if (failed <= 2 && ! conf->mddev->ro)
		for (i=0; i<failed;i++) {
		dev = &sh->dev[failed_num[i]];
		if (test_bit(R5_ReadError, &dev->flags)
		&& !test_bit(R5_LOCKED, &dev->flags)
		&& test_bit(R5_UPTODATE, &dev->flags)
		) {
		if (!test_bit(R5_ReWrite, &dev->flags)) {
		set_bit(R5_Wantwrite, &dev->flags);
		set_bit(R5_ReWrite, &dev->flags);
		set_bit(R5_LOCKED, &dev->flags);
		} else {
		/* let's read it back */
		set_bit(R5_Wantread, &dev->flags);
		set_bit(R5_LOCKED, &dev->flags);
		}
		}
		}
		spin_unlock(&sh->lock);

		while ((bi=return_bi)) {

Admin message