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> > > [*] 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 > * > * 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 >