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Commit fc974ee2 authored by Vishal Verma's avatar Vishal Verma Committed by Dan Williams
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md: convert to use the generic badblocks code 

Retain badblocks as part of rdev, but use the accessor functions from
include/linux/badblocks for all manipulation.
Signed-off-by: default avatarVishal Verma <vishal.l.verma@intel.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent 99e6608c
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Showing with 28 additions and 528 deletions
drivers/md/md.c
View file @ fc974ee2
......@@ -34,6 +34,7 @@
#include <linux/kthread.h>
#include <linux/blkdev.h>
#include <linux/badblocks.h>
#include <linux/sysctl.h>
#include <linux/seq_file.h>
#include <linux/fs.h>
......@@ -709,8 +710,7 @@ 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);
......@@ -1360,8 +1360,6 @@ 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;
......@@ -1486,8 +1484,7 @@ 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)
......@@ -2319,7 +2316,7 @@ void md_update_sb(struct mddev *mddev, int force_change)
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);
......@@ -2445,7 +2442,7 @@ void md_update_sb(struct mddev *mddev, int force_change)
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);
}
......@@ -3046,11 +3043,17 @@ 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);
......@@ -3165,14 +3168,7 @@ 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);
/*
......@@ -8478,254 +8474,9 @@ 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<<bb->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<<bb->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)
{
......@@ -8734,114 +8485,19 @@ 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<<bb->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)
{
......@@ -8849,133 +8505,11 @@ 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", &sector, &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)
{
......
drivers/md/md.h
View file @ fc974ee2
......@@ -17,6 +17,7 @@
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
#include <linux/badblocks.h>
#include <linux/kobject.h>
#include <linux/list.h>
#include <linux/mm.h>
......@@ -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 {
......
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