Alexey Kardashevskiy <a...@ozlabs.ru> writes:
> On 29/10/2020 11:40, Michael Ellerman wrote:
>> Alexey Kardashevskiy <a...@ozlabs.ru> writes:
>>> @@ -1126,7 +1129,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct
>>> device_node *pdn)
>>>
>>> mutex_lock(&direct_window_init_mutex);
>>>
>>> - dma_addr = find_existing_ddw(pdn);
>>> + dma_addr = find_existing_ddw(pdn, &len);
>>
>> I don't see len used anywhere?
>>
>>> if (dma_addr != 0)
>>> goto out_unlock;
>>>
>>> @@ -1212,14 +1215,26 @@ static u64 enable_ddw(struct pci_dev *dev, struct
>>> device_node *pdn)
>>> }
>>> /* verify the window * number of ptes will map the partition */
>>> /* check largest block * page size > max memory hotplug addr */
>>> - max_addr = ddw_memory_hotplug_max();
>>> - if (query.largest_available_block < (max_addr >> page_shift)) {
>>> - dev_dbg(&dev->dev, "can't map partition max 0x%llx with %llu "
>>> - "%llu-sized pages\n", max_addr,
>>> query.largest_available_block,
>>> - 1ULL << page_shift);
>>> + /*
>>> + * The "ibm,pmemory" can appear anywhere in the address space.
>>> + * Assuming it is still backed by page structs, try MAX_PHYSMEM_BITS
>>> + * for the upper limit and fallback to max RAM otherwise but this
>>> + * disables device::dma_ops_bypass.
>>> + */
>>> + len = max_ram_len;
>>
>> Here you override whatever find_existing_ddw() wrote to len?
>
> Not always, there is a bunch of gotos before this line to the end of the
> function and one (which returns the existing window) is legit. Thanks,
Ah yep I see it.
Gotos considered confusing ;)
cheers
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