From patchwork Fri Dec 25 02:20:34 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Verma, Vishal L" X-Patchwork-Id: 7920341 Return-Path: X-Original-To: patchwork-linux-block@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 14CC89F318 for ; Fri, 25 Dec 2015 02:22:10 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5D11720412 for ; Fri, 25 Dec 2015 02:22:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8C64420460 for ; Fri, 25 Dec 2015 02:22:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754387AbbLYCV5 (ORCPT ); Thu, 24 Dec 2015 21:21:57 -0500 Received: from mga03.intel.com ([134.134.136.65]:39524 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754460AbbLYCVc (ORCPT ); Thu, 24 Dec 2015 21:21:32 -0500 Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga103.jf.intel.com with ESMTP; 24 Dec 2015 18:21:31 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,476,1444719600"; d="scan'208";a="18931367" Received: from omniknight.lm.intel.com ([10.232.112.62]) by fmsmga004.fm.intel.com with ESMTP; 24 Dec 2015 18:21:32 -0800 From: Vishal Verma To: linux-nvdimm@lists.01.org Cc: Vishal Verma , linux-block@vger.kernel.org, linux-raid@vger.kernel.org, linux-scsi@vger.kernel.org, Jens Axboe , NeilBrown , Jeff Moyer , Dan Williams Subject: [PATCH v5 3/3] md: convert to use the generic badblocks code Date: Thu, 24 Dec 2015 19:20:34 -0700 Message-Id: <1451010034-11236-4-git-send-email-vishal.l.verma@intel.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1451010034-11236-1-git-send-email-vishal.l.verma@intel.com> References: <1451010034-11236-1-git-send-email-vishal.l.verma@intel.com> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Retain badblocks as part of rdev, but use the accessor functions from include/linux/badblocks for all manipulation. Signed-off-by: Vishal Verma --- drivers/md/md.c | 516 +++----------------------------------------------------- drivers/md/md.h | 40 +---- 2 files changed, 28 insertions(+), 528 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index dbedc58..51dc9f3 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -34,6 +34,7 @@ #include #include +#include #include #include #include @@ -710,8 +711,7 @@ void md_rdev_clear(struct md_rdev *rdev) put_page(rdev->bb_page); rdev->bb_page = NULL; } - kfree(rdev->badblocks.page); - rdev->badblocks.page = NULL; + badblocks_free(&rdev->badblocks); } EXPORT_SYMBOL_GPL(md_rdev_clear); @@ -1361,8 +1361,6 @@ static __le32 calc_sb_1_csum(struct mdp_superblock_1 *sb) return cpu_to_le32(csum); } -static int md_set_badblocks(struct badblocks *bb, sector_t s, int sectors, - int acknowledged); static int super_1_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_version) { struct mdp_superblock_1 *sb; @@ -1487,8 +1485,7 @@ static int super_1_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_ count <<= sb->bblog_shift; if (bb + 1 == 0) break; - if (md_set_badblocks(&rdev->badblocks, - sector, count, 1) == 0) + if (badblocks_set(&rdev->badblocks, sector, count, 1)) return -EINVAL; } } else if (sb->bblog_offset != 0) @@ -2320,7 +2317,7 @@ repeat: rdev_for_each(rdev, mddev) { if (rdev->badblocks.changed) { rdev->badblocks.changed = 0; - md_ack_all_badblocks(&rdev->badblocks); + ack_all_badblocks(&rdev->badblocks); md_error(mddev, rdev); } clear_bit(Blocked, &rdev->flags); @@ -2446,7 +2443,7 @@ repeat: clear_bit(Blocked, &rdev->flags); if (any_badblocks_changed) - md_ack_all_badblocks(&rdev->badblocks); + ack_all_badblocks(&rdev->badblocks); clear_bit(BlockedBadBlocks, &rdev->flags); wake_up(&rdev->blocked_wait); } @@ -3054,11 +3051,17 @@ static ssize_t recovery_start_store(struct md_rdev *rdev, const char *buf, size_ static struct rdev_sysfs_entry rdev_recovery_start = __ATTR(recovery_start, S_IRUGO|S_IWUSR, recovery_start_show, recovery_start_store); -static ssize_t -badblocks_show(struct badblocks *bb, char *page, int unack); -static ssize_t -badblocks_store(struct badblocks *bb, const char *page, size_t len, int unack); - +/* sysfs access to bad-blocks list. + * We present two files. + * 'bad-blocks' lists sector numbers and lengths of ranges that + * are recorded as bad. The list is truncated to fit within + * the one-page limit of sysfs. + * Writing "sector length" to this file adds an acknowledged + * bad block list. + * 'unacknowledged-bad-blocks' lists bad blocks that have not yet + * been acknowledged. Writing to this file adds bad blocks + * without acknowledging them. This is largely for testing. + */ static ssize_t bb_show(struct md_rdev *rdev, char *page) { return badblocks_show(&rdev->badblocks, page, 0); @@ -3173,14 +3176,7 @@ int md_rdev_init(struct md_rdev *rdev) * This reserves the space even on arrays where it cannot * be used - I wonder if that matters */ - rdev->badblocks.count = 0; - rdev->badblocks.shift = -1; /* disabled until explicitly enabled */ - rdev->badblocks.page = kmalloc(PAGE_SIZE, GFP_KERNEL); - seqlock_init(&rdev->badblocks.lock); - if (rdev->badblocks.page == NULL) - return -ENOMEM; - - return 0; + return badblocks_init(&rdev->badblocks, 0); } EXPORT_SYMBOL_GPL(md_rdev_init); /* @@ -8486,254 +8482,9 @@ void md_finish_reshape(struct mddev *mddev) } EXPORT_SYMBOL(md_finish_reshape); -/* Bad block management. - * We can record which blocks on each device are 'bad' and so just - * fail those blocks, or that stripe, rather than the whole device. - * Entries in the bad-block table are 64bits wide. This comprises: - * Length of bad-range, in sectors: 0-511 for lengths 1-512 - * Start of bad-range, sector offset, 54 bits (allows 8 exbibytes) - * A 'shift' can be set so that larger blocks are tracked and - * consequently larger devices can be covered. - * 'Acknowledged' flag - 1 bit. - the most significant bit. - * - * Locking of the bad-block table uses a seqlock so md_is_badblock - * might need to retry if it is very unlucky. - * We will sometimes want to check for bad blocks in a bi_end_io function, - * so we use the write_seqlock_irq variant. - * - * When looking for a bad block we specify a range and want to - * know if any block in the range is bad. So we binary-search - * to the last range that starts at-or-before the given endpoint, - * (or "before the sector after the target range") - * then see if it ends after the given start. - * We return - * 0 if there are no known bad blocks in the range - * 1 if there are known bad block which are all acknowledged - * -1 if there are bad blocks which have not yet been acknowledged in metadata. - * plus the start/length of the first bad section we overlap. - */ -int md_is_badblock(struct badblocks *bb, sector_t s, int sectors, - sector_t *first_bad, int *bad_sectors) -{ - int hi; - int lo; - u64 *p = bb->page; - int rv; - sector_t target = s + sectors; - unsigned seq; - - if (bb->shift > 0) { - /* round the start down, and the end up */ - s >>= bb->shift; - target += (1<shift) - 1; - target >>= bb->shift; - sectors = target - s; - } - /* 'target' is now the first block after the bad range */ - -retry: - seq = read_seqbegin(&bb->lock); - lo = 0; - rv = 0; - hi = bb->count; - - /* Binary search between lo and hi for 'target' - * i.e. for the last range that starts before 'target' - */ - /* INVARIANT: ranges before 'lo' and at-or-after 'hi' - * are known not to be the last range before target. - * VARIANT: hi-lo is the number of possible - * ranges, and decreases until it reaches 1 - */ - while (hi - lo > 1) { - int mid = (lo + hi) / 2; - sector_t a = BB_OFFSET(p[mid]); - if (a < target) - /* This could still be the one, earlier ranges - * could not. */ - lo = mid; - else - /* This and later ranges are definitely out. */ - hi = mid; - } - /* 'lo' might be the last that started before target, but 'hi' isn't */ - if (hi > lo) { - /* need to check all range that end after 's' to see if - * any are unacknowledged. - */ - while (lo >= 0 && - BB_OFFSET(p[lo]) + BB_LEN(p[lo]) > s) { - if (BB_OFFSET(p[lo]) < target) { - /* starts before the end, and finishes after - * the start, so they must overlap - */ - if (rv != -1 && BB_ACK(p[lo])) - rv = 1; - else - rv = -1; - *first_bad = BB_OFFSET(p[lo]); - *bad_sectors = BB_LEN(p[lo]); - } - lo--; - } - } - - if (read_seqretry(&bb->lock, seq)) - goto retry; - - return rv; -} -EXPORT_SYMBOL_GPL(md_is_badblock); - -/* - * Add a range of bad blocks to the table. - * This might extend the table, or might contract it - * if two adjacent ranges can be merged. - * We binary-search to find the 'insertion' point, then - * decide how best to handle it. - */ -static int md_set_badblocks(struct badblocks *bb, sector_t s, int sectors, - int acknowledged) -{ - u64 *p; - int lo, hi; - int rv = 1; - unsigned long flags; - - if (bb->shift < 0) - /* badblocks are disabled */ - return 0; - - if (bb->shift) { - /* round the start down, and the end up */ - sector_t next = s + sectors; - s >>= bb->shift; - next += (1<shift) - 1; - next >>= bb->shift; - sectors = next - s; - } - - write_seqlock_irqsave(&bb->lock, flags); - - p = bb->page; - lo = 0; - hi = bb->count; - /* Find the last range that starts at-or-before 's' */ - while (hi - lo > 1) { - int mid = (lo + hi) / 2; - sector_t a = BB_OFFSET(p[mid]); - if (a <= s) - lo = mid; - else - hi = mid; - } - if (hi > lo && BB_OFFSET(p[lo]) > s) - hi = lo; - - if (hi > lo) { - /* we found a range that might merge with the start - * of our new range - */ - sector_t a = BB_OFFSET(p[lo]); - sector_t e = a + BB_LEN(p[lo]); - int ack = BB_ACK(p[lo]); - if (e >= s) { - /* Yes, we can merge with a previous range */ - if (s == a && s + sectors >= e) - /* new range covers old */ - ack = acknowledged; - else - ack = ack && acknowledged; - - if (e < s + sectors) - e = s + sectors; - if (e - a <= BB_MAX_LEN) { - p[lo] = BB_MAKE(a, e-a, ack); - s = e; - } else { - /* does not all fit in one range, - * make p[lo] maximal - */ - if (BB_LEN(p[lo]) != BB_MAX_LEN) - p[lo] = BB_MAKE(a, BB_MAX_LEN, ack); - s = a + BB_MAX_LEN; - } - sectors = e - s; - } - } - if (sectors && hi < bb->count) { - /* 'hi' points to the first range that starts after 's'. - * Maybe we can merge with the start of that range */ - sector_t a = BB_OFFSET(p[hi]); - sector_t e = a + BB_LEN(p[hi]); - int ack = BB_ACK(p[hi]); - if (a <= s + sectors) { - /* merging is possible */ - if (e <= s + sectors) { - /* full overlap */ - e = s + sectors; - ack = acknowledged; - } else - ack = ack && acknowledged; - - a = s; - if (e - a <= BB_MAX_LEN) { - p[hi] = BB_MAKE(a, e-a, ack); - s = e; - } else { - p[hi] = BB_MAKE(a, BB_MAX_LEN, ack); - s = a + BB_MAX_LEN; - } - sectors = e - s; - lo = hi; - hi++; - } - } - if (sectors == 0 && hi < bb->count) { - /* we might be able to combine lo and hi */ - /* Note: 's' is at the end of 'lo' */ - sector_t a = BB_OFFSET(p[hi]); - int lolen = BB_LEN(p[lo]); - int hilen = BB_LEN(p[hi]); - int newlen = lolen + hilen - (s - a); - if (s >= a && newlen < BB_MAX_LEN) { - /* yes, we can combine them */ - int ack = BB_ACK(p[lo]) && BB_ACK(p[hi]); - p[lo] = BB_MAKE(BB_OFFSET(p[lo]), newlen, ack); - memmove(p + hi, p + hi + 1, - (bb->count - hi - 1) * 8); - bb->count--; - } - } - while (sectors) { - /* didn't merge (it all). - * Need to add a range just before 'hi' */ - if (bb->count >= MD_MAX_BADBLOCKS) { - /* No room for more */ - rv = 0; - break; - } else { - int this_sectors = sectors; - memmove(p + hi + 1, p + hi, - (bb->count - hi) * 8); - bb->count++; - - if (this_sectors > BB_MAX_LEN) - this_sectors = BB_MAX_LEN; - p[hi] = BB_MAKE(s, this_sectors, acknowledged); - sectors -= this_sectors; - s += this_sectors; - } - } - - bb->changed = 1; - if (!acknowledged) - bb->unacked_exist = 1; - write_sequnlock_irqrestore(&bb->lock, flags); - - return rv; -} +/* Bad block management */ +/* Returns 1 on success, 0 on failure */ int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors, int is_new) { @@ -8742,114 +8493,19 @@ int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors, s += rdev->new_data_offset; else s += rdev->data_offset; - rv = md_set_badblocks(&rdev->badblocks, - s, sectors, 0); - if (rv) { + rv = badblocks_set(&rdev->badblocks, s, sectors, 0); + if (rv == 0) { /* Make sure they get written out promptly */ sysfs_notify_dirent_safe(rdev->sysfs_state); set_bit(MD_CHANGE_CLEAN, &rdev->mddev->flags); set_bit(MD_CHANGE_PENDING, &rdev->mddev->flags); md_wakeup_thread(rdev->mddev->thread); - } - return rv; + return 1; + } else + return 0; } EXPORT_SYMBOL_GPL(rdev_set_badblocks); -/* - * Remove a range of bad blocks from the table. - * This may involve extending the table if we spilt a region, - * but it must not fail. So if the table becomes full, we just - * drop the remove request. - */ -static int md_clear_badblocks(struct badblocks *bb, sector_t s, int sectors) -{ - u64 *p; - int lo, hi; - sector_t target = s + sectors; - int rv = 0; - - if (bb->shift > 0) { - /* When clearing we round the start up and the end down. - * This should not matter as the shift should align with - * the block size and no rounding should ever be needed. - * However it is better the think a block is bad when it - * isn't than to think a block is not bad when it is. - */ - s += (1<shift) - 1; - s >>= bb->shift; - target >>= bb->shift; - sectors = target - s; - } - - write_seqlock_irq(&bb->lock); - - p = bb->page; - lo = 0; - hi = bb->count; - /* Find the last range that starts before 'target' */ - while (hi - lo > 1) { - int mid = (lo + hi) / 2; - sector_t a = BB_OFFSET(p[mid]); - if (a < target) - lo = mid; - else - hi = mid; - } - if (hi > lo) { - /* p[lo] is the last range that could overlap the - * current range. Earlier ranges could also overlap, - * but only this one can overlap the end of the range. - */ - if (BB_OFFSET(p[lo]) + BB_LEN(p[lo]) > target) { - /* Partial overlap, leave the tail of this range */ - int ack = BB_ACK(p[lo]); - sector_t a = BB_OFFSET(p[lo]); - sector_t end = a + BB_LEN(p[lo]); - - if (a < s) { - /* we need to split this range */ - if (bb->count >= MD_MAX_BADBLOCKS) { - rv = -ENOSPC; - goto out; - } - memmove(p+lo+1, p+lo, (bb->count - lo) * 8); - bb->count++; - p[lo] = BB_MAKE(a, s-a, ack); - lo++; - } - p[lo] = BB_MAKE(target, end - target, ack); - /* there is no longer an overlap */ - hi = lo; - lo--; - } - while (lo >= 0 && - BB_OFFSET(p[lo]) + BB_LEN(p[lo]) > s) { - /* This range does overlap */ - if (BB_OFFSET(p[lo]) < s) { - /* Keep the early parts of this range. */ - int ack = BB_ACK(p[lo]); - sector_t start = BB_OFFSET(p[lo]); - p[lo] = BB_MAKE(start, s - start, ack); - /* now low doesn't overlap, so.. */ - break; - } - lo--; - } - /* 'lo' is strictly before, 'hi' is strictly after, - * anything between needs to be discarded - */ - if (hi - lo > 1) { - memmove(p+lo+1, p+hi, (bb->count - hi) * 8); - bb->count -= (hi - lo - 1); - } - } - - bb->changed = 1; -out: - write_sequnlock_irq(&bb->lock); - return rv; -} - int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors, int is_new) { @@ -8857,133 +8513,11 @@ int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors, s += rdev->new_data_offset; else s += rdev->data_offset; - return md_clear_badblocks(&rdev->badblocks, + return badblocks_clear(&rdev->badblocks, s, sectors); } EXPORT_SYMBOL_GPL(rdev_clear_badblocks); -/* - * Acknowledge all bad blocks in a list. - * This only succeeds if ->changed is clear. It is used by - * in-kernel metadata updates - */ -void md_ack_all_badblocks(struct badblocks *bb) -{ - if (bb->page == NULL || bb->changed) - /* no point even trying */ - return; - write_seqlock_irq(&bb->lock); - - if (bb->changed == 0 && bb->unacked_exist) { - u64 *p = bb->page; - int i; - for (i = 0; i < bb->count ; i++) { - if (!BB_ACK(p[i])) { - sector_t start = BB_OFFSET(p[i]); - int len = BB_LEN(p[i]); - p[i] = BB_MAKE(start, len, 1); - } - } - bb->unacked_exist = 0; - } - write_sequnlock_irq(&bb->lock); -} -EXPORT_SYMBOL_GPL(md_ack_all_badblocks); - -/* sysfs access to bad-blocks list. - * We present two files. - * 'bad-blocks' lists sector numbers and lengths of ranges that - * are recorded as bad. The list is truncated to fit within - * the one-page limit of sysfs. - * Writing "sector length" to this file adds an acknowledged - * bad block list. - * 'unacknowledged-bad-blocks' lists bad blocks that have not yet - * been acknowledged. Writing to this file adds bad blocks - * without acknowledging them. This is largely for testing. - */ - -static ssize_t -badblocks_show(struct badblocks *bb, char *page, int unack) -{ - size_t len; - int i; - u64 *p = bb->page; - unsigned seq; - - if (bb->shift < 0) - return 0; - -retry: - seq = read_seqbegin(&bb->lock); - - len = 0; - i = 0; - - while (len < PAGE_SIZE && i < bb->count) { - sector_t s = BB_OFFSET(p[i]); - unsigned int length = BB_LEN(p[i]); - int ack = BB_ACK(p[i]); - i++; - - if (unack && ack) - continue; - - len += snprintf(page+len, PAGE_SIZE-len, "%llu %u\n", - (unsigned long long)s << bb->shift, - length << bb->shift); - } - if (unack && len == 0) - bb->unacked_exist = 0; - - if (read_seqretry(&bb->lock, seq)) - goto retry; - - return len; -} - -#define DO_DEBUG 1 - -static ssize_t -badblocks_store(struct badblocks *bb, const char *page, size_t len, int unack) -{ - unsigned long long sector; - int length; - char newline; -#ifdef DO_DEBUG - /* Allow clearing via sysfs *only* for testing/debugging. - * Normally only a successful write may clear a badblock - */ - int clear = 0; - if (page[0] == '-') { - clear = 1; - page++; - } -#endif /* DO_DEBUG */ - - switch (sscanf(page, "%llu %d%c", §or, &length, &newline)) { - case 3: - if (newline != '\n') - return -EINVAL; - case 2: - if (length <= 0) - return -EINVAL; - break; - default: - return -EINVAL; - } - -#ifdef DO_DEBUG - if (clear) { - md_clear_badblocks(bb, sector, length); - return len; - } -#endif /* DO_DEBUG */ - if (md_set_badblocks(bb, sector, length, !unack)) - return len; - else - return -ENOSPC; -} - static int md_notify_reboot(struct notifier_block *this, unsigned long code, void *x) { diff --git a/drivers/md/md.h b/drivers/md/md.h index ca0b643..75b9aaa 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -17,6 +17,7 @@ #include #include +#include #include #include #include @@ -28,13 +29,6 @@ #define MaxSector (~(sector_t)0) -/* Bad block numbers are stored sorted in a single page. - * 64bits is used for each block or extent. - * 54 bits are sector number, 9 bits are extent size, - * 1 bit is an 'acknowledged' flag. - */ -#define MD_MAX_BADBLOCKS (PAGE_SIZE/8) - /* * MD's 'extended' device */ @@ -117,22 +111,7 @@ struct md_rdev { struct kernfs_node *sysfs_state; /* handle for 'state' * sysfs entry */ - struct badblocks { - int count; /* count of bad blocks */ - int unacked_exist; /* there probably are unacknowledged - * bad blocks. This is only cleared - * when a read discovers none - */ - int shift; /* shift from sectors to block size - * a -ve shift means badblocks are - * disabled.*/ - u64 *page; /* badblock list */ - int changed; - seqlock_t lock; - - sector_t sector; - sector_t size; /* in sectors */ - } badblocks; + struct badblocks badblocks; }; enum flag_bits { Faulty, /* device is known to have a fault */ @@ -185,22 +164,11 @@ enum flag_bits { */ }; -#define BB_LEN_MASK (0x00000000000001FFULL) -#define BB_OFFSET_MASK (0x7FFFFFFFFFFFFE00ULL) -#define BB_ACK_MASK (0x8000000000000000ULL) -#define BB_MAX_LEN 512 -#define BB_OFFSET(x) (((x) & BB_OFFSET_MASK) >> 9) -#define BB_LEN(x) (((x) & BB_LEN_MASK) + 1) -#define BB_ACK(x) (!!((x) & BB_ACK_MASK)) -#define BB_MAKE(a, l, ack) (((a)<<9) | ((l)-1) | ((u64)(!!(ack)) << 63)) - -extern int md_is_badblock(struct badblocks *bb, sector_t s, int sectors, - sector_t *first_bad, int *bad_sectors); static inline int is_badblock(struct md_rdev *rdev, sector_t s, int sectors, sector_t *first_bad, int *bad_sectors) { if (unlikely(rdev->badblocks.count)) { - int rv = md_is_badblock(&rdev->badblocks, rdev->data_offset + s, + int rv = badblocks_check(&rdev->badblocks, rdev->data_offset + s, sectors, first_bad, bad_sectors); if (rv) @@ -213,8 +181,6 @@ extern int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors, int is_new); extern int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors, int is_new); -extern void md_ack_all_badblocks(struct badblocks *bb); - struct md_cluster_info; struct mddev {