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author | kib <kib@FreeBSD.org> | 2012-05-12 20:42:56 +0000 |
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committer | kib <kib@FreeBSD.org> | 2012-05-12 20:42:56 +0000 |
commit | 9ff1ec42a4c0d37d3675e60e7b68cae42df1a954 (patch) | |
tree | 0b49fefb6622aaedac7bf526163774e487e14627 /sys/vm/vm_phys.c | |
parent | 1ad1048d19f6c3f268b6cd701a9aa01021fea708 (diff) | |
download | FreeBSD-src-9ff1ec42a4c0d37d3675e60e7b68cae42df1a954.zip FreeBSD-src-9ff1ec42a4c0d37d3675e60e7b68cae42df1a954.tar.gz |
Add a facility to register a range of physical addresses to be used
for allocation of fictitious pages, for which PHYS_TO_VM_PAGE()
returns proper fictitious vm_page_t. The range should be de-registered
after consumer stopped using it.
De-inline the PHYS_TO_VM_PAGE() since it now carries code to iterate
over registered ranges.
A hash container might be developed instead of range registration
interface, and fake pages could be put automatically into the hash,
were PHYS_TO_VM_PAGE() could look them up later. This should be
considered before the MFC of the commit is done.
Sponsored by: The FreeBSD Foundation
Reviewed by: alc
MFC after: 1 month
Diffstat (limited to 'sys/vm/vm_phys.c')
-rw-r--r-- | sys/vm/vm_phys.c | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/sys/vm/vm_phys.c b/sys/vm/vm_phys.c index 8c026e6..9cfea23 100644 --- a/sys/vm/vm_phys.c +++ b/sys/vm/vm_phys.c @@ -87,6 +87,15 @@ static struct vm_phys_seg vm_phys_segs[VM_PHYSSEG_MAX]; static int vm_phys_nsegs; +#define VM_PHYS_FICTITIOUS_NSEGS 8 +static struct vm_phys_fictitious_seg { + vm_paddr_t start; + vm_paddr_t end; + vm_page_t first_page; +} vm_phys_fictitious_segs[VM_PHYS_FICTITIOUS_NSEGS]; +static struct mtx vm_phys_fictitious_reg_mtx; +MALLOC_DEFINE(M_FICT_PAGES, "", ""); + static struct vm_freelist vm_phys_free_queues[VM_RAW_NFREELIST][VM_NFREEPOOL][VM_NFREEORDER]; static struct vm_freelist @@ -366,6 +375,8 @@ vm_phys_init(void) for (flind = 0; flind < vm_nfreelists; flind++) vm_phys_lookup_lists[0][flind] = &vm_phys_free_queues[flind]; #endif + + mtx_init(&vm_phys_fictitious_reg_mtx, "vmfctr", NULL, MTX_DEF); } /* @@ -510,6 +521,112 @@ vm_phys_paddr_to_vm_page(vm_paddr_t pa) return (NULL); } +vm_page_t +vm_phys_fictitious_to_vm_page(vm_paddr_t pa) +{ + struct vm_phys_fictitious_seg *seg; + vm_page_t m; + int segind; + + m = NULL; + for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) { + seg = &vm_phys_fictitious_segs[segind]; + if (pa >= seg->start && pa < seg->end) { + m = &seg->first_page[atop(pa - seg->start)]; + KASSERT((m->flags & PG_FICTITIOUS) != 0, + ("%p not fictitious", m)); + break; + } + } + return (m); +} + +int +vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end, + vm_memattr_t memattr) +{ + struct vm_phys_fictitious_seg *seg; + vm_page_t fp; + long i, page_count; + int segind; +#ifdef VM_PHYSSEG_DENSE + long pi; + boolean_t malloced; +#endif + + page_count = (end - start) / PAGE_SIZE; + +#ifdef VM_PHYSSEG_DENSE + pi = atop(start); + if (pi >= first_page && atop(end) < vm_page_array_size) { + fp = &vm_page_array[pi - first_page]; + malloced = FALSE; + } else +#endif + { + fp = malloc(page_count * sizeof(struct vm_page), M_FICT_PAGES, + M_WAITOK | M_ZERO); +#ifdef VM_PHYSSEG_DENSE + malloced = TRUE; +#endif + } + for (i = 0; i < page_count; i++) { + vm_page_initfake(&fp[i], start + PAGE_SIZE * i, memattr); + pmap_page_init(&fp[i]); + fp[i].oflags &= ~(VPO_BUSY | VPO_UNMANAGED); + } + mtx_lock(&vm_phys_fictitious_reg_mtx); + for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) { + seg = &vm_phys_fictitious_segs[segind]; + if (seg->start == 0 && seg->end == 0) { + seg->start = start; + seg->end = end; + seg->first_page = fp; + mtx_unlock(&vm_phys_fictitious_reg_mtx); + return (0); + } + } + mtx_unlock(&vm_phys_fictitious_reg_mtx); +#ifdef VM_PHYSSEG_DENSE + if (malloced) +#endif + free(fp, M_FICT_PAGES); + return (EBUSY); +} + +void +vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end) +{ + struct vm_phys_fictitious_seg *seg; + vm_page_t fp; + int segind; +#ifdef VM_PHYSSEG_DENSE + long pi; +#endif + +#ifdef VM_PHYSSEG_DENSE + pi = atop(start); +#endif + + mtx_lock(&vm_phys_fictitious_reg_mtx); + for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) { + seg = &vm_phys_fictitious_segs[segind]; + if (seg->start == start && seg->end == end) { + seg->start = seg->end = 0; + fp = seg->first_page; + seg->first_page = NULL; + mtx_unlock(&vm_phys_fictitious_reg_mtx); +#ifdef VM_PHYSSEG_DENSE + if (pi < first_page || atop(end) >= vm_page_array_size) +#endif + free(fp, M_FICT_PAGES); + return; + } + } + mtx_unlock(&vm_phys_fictitious_reg_mtx); + KASSERT(0, ("Unregistering not registered fictitious range")); +} + /* * Find the segment containing the given physical address. */ |