int badblocks_check(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;
- }
- /* '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;
+ return _badblocks_check(bb, s, sectors, first_bad, bad_sectors);
}
EXPORT_SYMBOL_GPL(badblocks_check);
int badblocks_set(struct badblocks *bb, sector_t s, int sectors,
int acknowledged)
{
- u64 *p;
- int lo, hi;
- int rv = 0;
- unsigned long flags;
-
- if (bb->shift < 0)
- /* badblocks are disabled */
- return 1;
-
- 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 >= MAX_BADBLOCKS) {
- /* No room for more */
- rv = 1;
- 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;
- else
- badblocks_update_acked(bb);
- write_sequnlock_irqrestore(&bb->lock, flags);
-
- return rv;
+ return _badblocks_set(bb, s, sectors, acknowledged);
}
EXPORT_SYMBOL_GPL(badblocks_set);
*/
int badblocks_clear(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;
- }
-
- 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) &&
- (BB_OFFSET(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 >= 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) &&
- (BB_OFFSET(p[lo]) < target)) {
- /* 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);
- }
- }
-
- badblocks_update_acked(bb);
- bb->changed = 1;
-out:
- write_sequnlock_irq(&bb->lock);
- return rv;
+ return _badblocks_clear(bb, s, sectors);
}
EXPORT_SYMBOL_GPL(badblocks_clear);
projects / linux.git / commitdiff