On 7/28/21 6:56 AM, Dan Williams wrote: > On Wed, Jul 14, 2021 at 12:36 PM Joao Martins <joao.m.martins@xxxxxxxxxx> wrote: >> >> In support of using compound pages for devmap mappings, plumb the pgmap >> down to the vmemmap_populate implementation. Note that while altmap is >> retrievable from pgmap the memory hotplug code passes altmap without >> pgmap[*], so both need to be independently plumbed. >> >> So in addition to @altmap, pass @pgmap to sparse section populate >> functions namely: >> >> sparse_add_section >> section_activate >> populate_section_memmap >> __populate_section_memmap >> >> Passing @pgmap allows __populate_section_memmap() to both fetch the >> geometry in which memmap metadata is created for and also to let >> sparse-vmemmap fetch pgmap ranges to co-relate to a given section and pick >> whether to just reuse tail pages from past onlined sections. > > Looks good to me, just one quibble below: > > Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx> > Thank you! >> >> [*] https://lore.kernel.org/linux-mm/20210319092635.6214-1-osalvador@xxxxxxx/ >> >> Signed-off-by: Joao Martins <joao.m.martins@xxxxxxxxxx> >> --- >> include/linux/memory_hotplug.h | 5 ++++- >> include/linux/mm.h | 3 ++- >> mm/memory_hotplug.c | 3 ++- >> mm/sparse-vmemmap.c | 3 ++- >> mm/sparse.c | 24 +++++++++++++++--------- >> 5 files changed, 25 insertions(+), 13 deletions(-) >> >> diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h >> index a7fd2c3ccb77..9b1bca80224d 100644 >> --- a/include/linux/memory_hotplug.h >> +++ b/include/linux/memory_hotplug.h >> @@ -14,6 +14,7 @@ struct mem_section; >> struct memory_block; >> struct resource; >> struct vmem_altmap; >> +struct dev_pagemap; >> >> #ifdef CONFIG_MEMORY_HOTPLUG >> struct page *pfn_to_online_page(unsigned long pfn); >> @@ -60,6 +61,7 @@ typedef int __bitwise mhp_t; >> struct mhp_params { >> struct vmem_altmap *altmap; >> pgprot_t pgprot; >> + struct dev_pagemap *pgmap; >> }; >> >> bool mhp_range_allowed(u64 start, u64 size, bool need_mapping); >> @@ -333,7 +335,8 @@ extern void remove_pfn_range_from_zone(struct zone *zone, >> unsigned long nr_pages); >> extern bool is_memblock_offlined(struct memory_block *mem); >> extern int sparse_add_section(int nid, unsigned long pfn, >> - unsigned long nr_pages, struct vmem_altmap *altmap); >> + unsigned long nr_pages, struct vmem_altmap *altmap, >> + struct dev_pagemap *pgmap); >> extern void sparse_remove_section(struct mem_section *ms, >> unsigned long pfn, unsigned long nr_pages, >> unsigned long map_offset, struct vmem_altmap *altmap); >> diff --git a/include/linux/mm.h b/include/linux/mm.h >> index 7ca22e6e694a..f244a9219ce4 100644 >> --- a/include/linux/mm.h >> +++ b/include/linux/mm.h >> @@ -3083,7 +3083,8 @@ int vmemmap_remap_alloc(unsigned long start, unsigned long end, >> >> void *sparse_buffer_alloc(unsigned long size); >> struct page * __populate_section_memmap(unsigned long pfn, >> - unsigned long nr_pages, int nid, struct vmem_altmap *altmap); >> + unsigned long nr_pages, int nid, struct vmem_altmap *altmap, >> + struct dev_pagemap *pgmap); >> pgd_t *vmemmap_pgd_populate(unsigned long addr, int node); >> p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node); >> pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node); >> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c >> index 8cb75b26ea4f..c728a8ff38ad 100644 >> --- a/mm/memory_hotplug.c >> +++ b/mm/memory_hotplug.c >> @@ -268,7 +268,8 @@ int __ref __add_pages(int nid, unsigned long pfn, unsigned long nr_pages, >> /* Select all remaining pages up to the next section boundary */ >> cur_nr_pages = min(end_pfn - pfn, >> SECTION_ALIGN_UP(pfn + 1) - pfn); >> - err = sparse_add_section(nid, pfn, cur_nr_pages, altmap); >> + err = sparse_add_section(nid, pfn, cur_nr_pages, altmap, >> + params->pgmap); >> if (err) >> break; >> cond_resched(); >> diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c >> index bdce883f9286..80d3ba30d345 100644 >> --- a/mm/sparse-vmemmap.c >> +++ b/mm/sparse-vmemmap.c >> @@ -603,7 +603,8 @@ int __meminit vmemmap_populate_basepages(unsigned long start, unsigned long end, >> } >> >> struct page * __meminit __populate_section_memmap(unsigned long pfn, >> - unsigned long nr_pages, int nid, struct vmem_altmap *altmap) >> + unsigned long nr_pages, int nid, struct vmem_altmap *altmap, >> + struct dev_pagemap *pgmap) >> { >> unsigned long start = (unsigned long) pfn_to_page(pfn); >> unsigned long end = start + nr_pages * sizeof(struct page); >> diff --git a/mm/sparse.c b/mm/sparse.c >> index 6326cdf36c4f..5310be6171f1 100644 >> --- a/mm/sparse.c >> +++ b/mm/sparse.c >> @@ -453,7 +453,8 @@ static unsigned long __init section_map_size(void) >> } >> >> struct page __init *__populate_section_memmap(unsigned long pfn, >> - unsigned long nr_pages, int nid, struct vmem_altmap *altmap) >> + unsigned long nr_pages, int nid, struct vmem_altmap *altmap, >> + struct dev_pagemap *pgmap) >> { >> unsigned long size = section_map_size(); >> struct page *map = sparse_buffer_alloc(size); >> @@ -552,7 +553,7 @@ static void __init sparse_init_nid(int nid, unsigned long pnum_begin, >> break; >> >> map = __populate_section_memmap(pfn, PAGES_PER_SECTION, >> - nid, NULL); >> + nid, NULL, NULL); >> if (!map) { >> pr_err("%s: node[%d] memory map backing failed. Some memory will not be available.", >> __func__, nid); >> @@ -657,9 +658,10 @@ void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn) >> >> #ifdef CONFIG_SPARSEMEM_VMEMMAP >> static struct page * __meminit populate_section_memmap(unsigned long pfn, >> - unsigned long nr_pages, int nid, struct vmem_altmap *altmap) >> + unsigned long nr_pages, int nid, struct vmem_altmap *altmap, >> + struct dev_pagemap *pgmap) >> { >> - return __populate_section_memmap(pfn, nr_pages, nid, altmap); >> + return __populate_section_memmap(pfn, nr_pages, nid, altmap, pgmap); >> } >> >> static void depopulate_section_memmap(unsigned long pfn, unsigned long nr_pages, >> @@ -728,7 +730,8 @@ static int fill_subsection_map(unsigned long pfn, unsigned long nr_pages) >> } >> #else >> struct page * __meminit populate_section_memmap(unsigned long pfn, >> - unsigned long nr_pages, int nid, struct vmem_altmap *altmap) >> + unsigned long nr_pages, int nid, struct vmem_altmap *altmap, >> + struct dev_pagemap *pgmap) >> { >> return kvmalloc_node(array_size(sizeof(struct page), >> PAGES_PER_SECTION), GFP_KERNEL, nid); >> @@ -851,7 +854,8 @@ static void section_deactivate(unsigned long pfn, unsigned long nr_pages, >> } >> >> static struct page * __meminit section_activate(int nid, unsigned long pfn, >> - unsigned long nr_pages, struct vmem_altmap *altmap) >> + unsigned long nr_pages, struct vmem_altmap *altmap, >> + struct dev_pagemap *pgmap) >> { >> struct mem_section *ms = __pfn_to_section(pfn); >> struct mem_section_usage *usage = NULL; >> @@ -883,7 +887,7 @@ static struct page * __meminit section_activate(int nid, unsigned long pfn, >> if (nr_pages < PAGES_PER_SECTION && early_section(ms)) >> return pfn_to_page(pfn); >> >> - memmap = populate_section_memmap(pfn, nr_pages, nid, altmap); >> + memmap = populate_section_memmap(pfn, nr_pages, nid, altmap, pgmap); >> if (!memmap) { >> section_deactivate(pfn, nr_pages, altmap); >> return ERR_PTR(-ENOMEM); >> @@ -898,6 +902,7 @@ static struct page * __meminit section_activate(int nid, unsigned long pfn, >> * @start_pfn: start pfn of the memory range >> * @nr_pages: number of pfns to add in the section >> * @altmap: device page map >> + * @pgmap: device page map object that owns the section > > Since this patch is touching the kdoc, might as well fix it up > properly for @altmap, and perhaps an alternate note for @pgmap: > > @altmap: alternate pfns to allocate the memmap backing store > @pgmap: alternate compound page geometry for devmap mappings > Ah, indeed. I fixed it up and also added this to the commit message: "While at it, fix the kdoc for @altmap for sparse_add_section()." > >> * >> * This is only intended for hotplug. >> * >> @@ -911,7 +916,8 @@ static struct page * __meminit section_activate(int nid, unsigned long pfn, >> * * -ENOMEM - Out of memory. >> */ >> int __meminit sparse_add_section(int nid, unsigned long start_pfn, >> - unsigned long nr_pages, struct vmem_altmap *altmap) >> + unsigned long nr_pages, struct vmem_altmap *altmap, >> + struct dev_pagemap *pgmap) >> { >> unsigned long section_nr = pfn_to_section_nr(start_pfn); >> struct mem_section *ms; >> @@ -922,7 +928,7 @@ int __meminit sparse_add_section(int nid, unsigned long start_pfn, >> if (ret < 0) >> return ret; >> >> - memmap = section_activate(nid, start_pfn, nr_pages, altmap); >> + memmap = section_activate(nid, start_pfn, nr_pages, altmap, pgmap); >> if (IS_ERR(memmap)) >> return PTR_ERR(memmap); >> >> -- >> 2.17.1 >>