[PATCH] lmb: remove overlapping region with next range

[Kumar, Udit]

On 9/24/2023 7:21 PM, Heinrich Schuchardt wrote:
>
> Am 24. September 2023 13:18:32 MESZ schrieb Udit Kumar <u-kumar1 at ti.com>:
>> In case of new memory range to be added is coalesced
>> with any already added non last lmb region.
>>
>> And there is possibility that, then region in which new memory
>> range added is not adjacent to next region. But have some
>> sections are overlapping.
>>
>> So along with adjacency check with next lmb region,
>> check for overlap should be done.
>>
>> In case overlap  is found, adjust and merge these two lmb
>> region into one.
>>
>> Reported-by: Suman Anna <s-anna at ti.com>
>> Signed-off-by: Udit Kumar <u-kumar1 at ti.com>
>> ---
>> logs
>> https://gist.github.com/uditkumarti/5d08c34442235ad270cfa863792ebcdc
>> seqeunce : line 1 to 13
>> without fix : line 96-100
>> with fix : line 199-202
>>
>> lib/lmb.c | 37 +++++++++++++++++++++++++++++++++----
>> 1 file changed, 33 insertions(+), 4 deletions(-)
>>
>> diff --git a/lib/lmb.c b/lib/lmb.c
>> index b2c233edb6..2580d01d90 100644
>> --- a/lib/lmb.c
>> +++ b/lib/lmb.c
>> @@ -74,6 +74,16 @@ static long lmb_addrs_adjacent(phys_addr_t base1, phys_size_t size1,
>> 	return 0;
>> }
>>
>> +static long lmb_regions_overlap(struct lmb_region *rgn, unsigned long r1,
>> +				unsigned long r2)
>> +{
>> +	phys_addr_t base1 = rgn->region[r1].base;
>> +	phys_size_t size1 = rgn->region[r1].size;
>> +	phys_addr_t base2 = rgn->region[r2].base;
>> +	phys_size_t size2 = rgn->region[r2].size;
>> +
>> +	return lmb_addrs_overlap(base1, size1, base2, size2);
>> +}
>> static long lmb_regions_adjacent(struct lmb_region *rgn, unsigned long r1,
>> 				 unsigned long r2)
>> {
>> @@ -81,7 +91,6 @@ static long lmb_regions_adjacent(struct lmb_region *rgn, unsigned long r1,
>> 	phys_size_t size1 = rgn->region[r1].size;
>> 	phys_addr_t base2 = rgn->region[r2].base;
>> 	phys_size_t size2 = rgn->region[r2].size;
>> -
>> 	return lmb_addrs_adjacent(base1, size1, base2, size2);
>> }
>>
>> @@ -105,6 +114,23 @@ static void lmb_coalesce_regions(struct lmb_region *rgn, unsigned long r1,
>> 	lmb_remove_region(rgn, r2);
>> }
>>
>> +/*Assmptuon : base addr of region 1 < base addr of region 2*/
> Assumption


Thanks Heinrich  will fix this typo in v2.

Let me wait for other review feedback as well before proceeding for v2.


> Regards Heinrich
>
>> +static void lmb_fix_over_lap_regions(struct lmb_region *rgn, unsigned long r1,
>> +				     unsigned long r2)
>> +{
>> +	phys_addr_t base1 = rgn->region[r1].base;
>> +	phys_size_t size1 = rgn->region[r1].size;
>> +	phys_addr_t base2 = rgn->region[r2].base;
>> +	phys_size_t size2 = rgn->region[r2].size;
>> +
>> +	if (base1 + size1 > base2 + size2) {
>> +		printf("This will not be a case any time\n");
>> +		return;
>> +	}
>> +	rgn->region[r1].size = base2 + size2 - base1;
>> +	lmb_remove_region(rgn, r2);
>> +}
>> +
>> void lmb_init(struct lmb *lmb)
>> {
>> #if IS_ENABLED(CONFIG_LMB_USE_MAX_REGIONS)
>> @@ -249,7 +275,6 @@ static long lmb_add_region_flags(struct lmb_region *rgn, phys_addr_t base,
>> 		phys_size_t rgnflags = rgn->region[i].flags;
>> 		phys_addr_t end = base + size - 1;
>> 		phys_addr_t rgnend = rgnbase + rgnsize - 1;
>> -
>> 		if (rgnbase <= base && end <= rgnend) {
>> 			if (flags == rgnflags)
>> 				/* Already have this region, so we're done */
>> @@ -278,10 +303,14 @@ static long lmb_add_region_flags(struct lmb_region *rgn, phys_addr_t base,
>> 		}
>> 	}
>>
>> -	if ((i < rgn->cnt - 1) && lmb_regions_adjacent(rgn, i, i + 1)) {
>> -		if (rgn->region[i].flags == rgn->region[i + 1].flags) {
>> +	if (i < rgn->cnt - 1 && rgn->region[i].flags == rgn->region[i + 1].flags)  {
>> +		if (lmb_regions_adjacent(rgn, i, i + 1)) {
>> 			lmb_coalesce_regions(rgn, i, i + 1);
>> 			coalesced++;
>> +		} else if (lmb_regions_overlap(rgn, i, i + 1)) {
>> +			/* fix overlapping area */
>> +			lmb_fix_over_lap_regions(rgn, i, i + 1);
>> +			coalesced++;
>> 		}
>> 	}
>>