search for: dev_pagemap_kill

...ap->ops->page_free) { WARN(1, "Missing page_free method\n"); return -EINVAL; } @@ -75,6 +75,24 @@ static unsigned long pfn_next(unsigned long pfn) #define for_each_device_pfn(pfn, map) \ for (pfn = pfn_first(map); pfn < pfn_end(map); pfn = pfn_next(pfn)) +static void dev_pagemap_kill(struct dev_pagemap *pgmap) +{ + if (pgmap->ops && pgmap->ops->kill) + pgmap->ops->kill(pgmap); + else + percpu_ref_kill(pgmap->ref); +} + +static void dev_pagemap_cleanup(struct dev_pagemap *pgmap) +{ + if (pgmap->ops && pgmap->ops->cleanup) { + pgmap-&...

...(1, "Missing page_free method\n"); > return -EINVAL; > } > @@ -75,6 +75,24 @@ static unsigned long pfn_next(unsigned long pfn) > #define for_each_device_pfn(pfn, map) \ > for (pfn = pfn_first(map); pfn < pfn_end(map); pfn = pfn_next(pfn)) > > +static void dev_pagemap_kill(struct dev_pagemap *pgmap) > +{ > + if (pgmap->ops && pgmap->ops->kill) > + pgmap->ops->kill(pgmap); > + else > + percpu_ref_kill(pgmap->ref); > +} > + > +static void dev_pagemap_cleanup(struct dev_pagemap *pgmap) > +{ > + if (pgmap->ops...

...tart + resource_size(res)) >> PAGE_SHIFT; } -static unsigned long pfn_next(unsigned long pfn) -{ - if (pfn % 1024 == 0) - cond_resched(); - return pfn + 1; -} - -#define for_each_device_pfn(pfn, map) \ - for (pfn = pfn_first(map); pfn < pfn_end(map); pfn = pfn_next(pfn)) - static void dev_pagemap_kill(struct dev_pagemap *pgmap) { if (pgmap->ops && pgmap->ops->kill) @@ -128,12 +86,10 @@ void memunmap_pages(struct dev_pagemap *pgmap) { struct resource *res = &pgmap->res; struct page *first_page; - unsigned long pfn; int nid; dev_pagemap_kill(pgmap); - for_each...

...* This returns true if the page is reserved by ZONE_DEVICE driver. */ @@ -119,9 +106,6 @@ bool pfn_zone_device_reserved(unsigned long pfn) return ret; } -#define for_each_device_pfn(pfn, map, i) \ - for (pfn = pfn_first(map, i); pfn < pfn_end(map, i); pfn = pfn_next(pfn)) - static void dev_pagemap_kill(struct dev_pagemap *pgmap) { if (pgmap->ops && pgmap->ops->kill) @@ -177,20 +161,20 @@ static void pageunmap_range(struct dev_pagemap *pgmap, int range_id) void memunmap_pages(struct dev_pagemap *pgmap) { - unsigned long pfn; int i; dev_pagemap_kill(pgmap); for (i =...

...* This returns true if the page is reserved by ZONE_DEVICE driver. */ @@ -118,9 +82,6 @@ bool pfn_zone_device_reserved(unsigned long pfn) return ret; } -#define for_each_device_pfn(pfn, map, i) \ - for (pfn = pfn_first(map, i); pfn < pfn_end(map, i); pfn = pfn_next(pfn)) - static void dev_pagemap_kill(struct dev_pagemap *pgmap) { if (pgmap->ops && pgmap->ops->kill) @@ -176,20 +137,18 @@ static void pageunmap_range(struct dev_pagemap *pgmap, int range_id) void memunmap_pages(struct dev_pagemap *pgmap) { - unsigned long pfn; int i; dev_pagemap_kill(pgmap); for (i =...

...* This returns true if the page is reserved by ZONE_DEVICE driver. */ @@ -119,9 +106,6 @@ bool pfn_zone_device_reserved(unsigned long pfn) return ret; } -#define for_each_device_pfn(pfn, map, i) \ - for (pfn = pfn_first(map, i); pfn < pfn_end(map, i); pfn = pfn_next(pfn)) - static void dev_pagemap_kill(struct dev_pagemap *pgmap) { if (pgmap->ops && pgmap->ops->kill) @@ -177,20 +161,20 @@ static void pageunmap_range(struct dev_pagemap *pgmap, int range_id) void memunmap_pages(struct dev_pagemap *pgmap) { - unsigned long pfn; int i; dev_pagemap_kill(pgmap); for (i =...

Matthew Wilcox, Ira Weiny, and others have complained that ZONE_DEVICE struct page reference counting is ugly because they are "free" when the reference count is one instead of zero. This leads to explicit checks for ZONE_DEVICE pages in places like put_page(), GUP, THP splitting, and page migration which have to adjust the expected reference count when determining if the page is

This is still an RFC because after looking at the pmem/dax code some more, I realized that the ZONE_DEVICE struct pages are being inserted into the process' page tables with vmf_insert_mixed() and a zero refcount on the ZONE_DEVICE struct page. This is sort of OK because insert_pfn() increments the reference count on the pgmap which is what prevents memunmap_pages() from freeing the struct

...if (is_migration_entry(entry)) pmd_migration_entry_wait(mm, vmf.pmd); return 0; } diff --git a/mm/memremap.c b/mm/memremap.c index 03e38b7a38f1..4231054188b4 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -132,8 +132,13 @@ void memunmap_pages(struct dev_pagemap *pgmap) int nid; dev_pagemap_kill(pgmap); - for_each_device_pfn(pfn, pgmap) - put_page(pfn_to_page(pfn)); + for_each_device_pfn(pfn, pgmap) { + struct page *page = pfn_to_page(pfn); + unsigned int order = compound_order(page); + + put_page(page); + pfn += (1U << order) - 1; + } dev_pagemap_cleanup(pgmap); /* make s...

Hi Dan, Jérôme and Jason, below is a series that cleans up the dev_pagemap interface so that it is more easily usable, which removes the need to wrap it in hmm and thus allowing to kill a lot of code Note: this series is on top of Linux 5.2-rc5 and has some minor conflicts with the hmm tree that are easy to resolve. Diffstat summary: 32 files changed, 361 insertions(+), 1012 deletions(-) Git

...n_entry_wait(mm, vmf.pmd); > return 0; > } > diff --git a/mm/memremap.c b/mm/memremap.c > index 03e38b7a38f1..4231054188b4 100644 > --- a/mm/memremap.c > +++ b/mm/memremap.c > @@ -132,8 +132,13 @@ void memunmap_pages(struct dev_pagemap *pgmap) > int nid; > > dev_pagemap_kill(pgmap); > - for_each_device_pfn(pfn, pgmap) > - put_page(pfn_to_page(pfn)); > + for_each_device_pfn(pfn, pgmap) { > + struct page *page = pfn_to_page(pfn); > + unsigned int order = compound_order(page); > + > + put_page(page); > + pfn += (1U << order) - 1; > +...

...) - cond_resched(); - return pfn + 1; -} - /* * This returns true if the page is reserved by ZONE_DEVICE driver. */ @@ -176,13 +169,12 @@ static void pageunmap_range(struct dev_pagemap *pgmap, int range_id) void memunmap_pages(struct dev_pagemap *pgmap) { - unsigned long pfn; int i; dev_pagemap_kill(pgmap); for (i = 0; i < pgmap->nr_range; i++) - for_each_device_pfn(pfn, pgmap, i) - put_page(pfn_to_page(pfn)); + percpu_ref_put_many(pgmap->ref, pfn_end(pgmap, i) - + pfn_first(pgmap, i)); dev_pagemap_cleanup(pgmap); for (i = 0; i < pgmap->nr_range; i++) @@ -516,6...

Hi Dan, Jérôme and Jason, below is a series that cleans up the dev_pagemap interface so that it is more easily usable, which removes the need to wrap it in hmm and thus allowing to kill a lot of code Note: this series is on top of the rdma/hmm branch + the dev_pagemap releas fix series from Dan that went into 5.2-rc5. Git tree: git://git.infradead.org/users/hch/misc.git

Hi Dan, Jérôme and Jason, below is a series that cleans up the dev_pagemap interface so that it is more easily usable, which removes the need to wrap it in hmm and thus allowing to kill a lot of code Diffstat: 22 files changed, 245 insertions(+), 802 deletions(-) Git tree: git://git.infradead.org/users/hch/misc.git hmm-devmem-cleanup Gitweb:

These patches apply to linux-5.8.0-rc1. Patches 1-3 should probably go into 5.8, the others can be queued for 5.9. Patches 4-6 improve the HMM self tests. Patch 7-8 prepare nouveau for the meat of this series which adds support and testing for compound page mapping of system memory (patches 9-11) and compound page migration to device private memory (patches 12-16). Since these changes are split