| Message ID | 20211115193026.27568-8-alex.sierra@amd.com |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | Add MEMORY_DEVICE_COHERENT for coherent device memory mapping | expand |
Am 2021-11-15 um 2:30 p.m. schrieb Alex Sierra: > Device Coherent type uses device memory that is coherently accesible by > the CPU. This could be shown as SP (special purpose) memory range > at the BIOS-e820 memory enumeration. If no SP memory is supported in > system, this could be faked by setting CONFIG_EFI_FAKE_MEMMAP. > > Currently, test_hmm only supports two different SP ranges of at least > 256MB size. This could be specified in the kernel parameter variable > efi_fake_mem. Ex. Two SP ranges of 1GB starting at 0x100000000 & > 0x140000000 physical address. Ex. > efi_fake_mem=1G@0x100000000:0x40000,1G@0x140000000:0x40000 > > Signed-off-by: Alex Sierra <alex.sierra@amd.com> > --- > lib/test_hmm.c | 191 +++++++++++++++++++++++++++++++++----------- > lib/test_hmm_uapi.h | 15 ++-- > 2 files changed, 153 insertions(+), 53 deletions(-) > > diff --git a/lib/test_hmm.c b/lib/test_hmm.c > index 45334df28d7b..9e2cc0cd4412 100644 > --- a/lib/test_hmm.c > +++ b/lib/test_hmm.c > @@ -471,6 +471,7 @@ static int dmirror_allocate_chunk(struct dmirror_device *mdevice, > unsigned long pfn_first; > unsigned long pfn_last; > void *ptr; > + int ret = -ENOMEM; > > devmem = kzalloc(sizeof(*devmem), GFP_KERNEL); > if (!devmem) > @@ -553,7 +554,7 @@ static int dmirror_allocate_chunk(struct dmirror_device *mdevice, > } > spin_unlock(&mdevice->lock); > > - return true; > + return 0; You're changing the meaning of the return value, but you're not updating the callers. I think at least dmirror_devmem_alloc_page will be broken by this change. > > err_release: > mutex_unlock(&mdevice->devmem_lock); > @@ -562,7 +563,7 @@ static int dmirror_allocate_chunk(struct dmirror_device *mdevice, > err_devmem: > kfree(devmem); > > - return false; > + return ret; > } > > static struct page *dmirror_devmem_alloc_page(struct dmirror_device *mdevice) > @@ -571,8 +572,10 @@ static struct page *dmirror_devmem_alloc_page(struct dmirror_device *mdevice) > struct page *rpage; > > /* > - * This is a fake device so we alloc real system memory to store > - * our device memory. > + * For ZONE_DEVICE private type, this is a fake device so we alloc real > + * system memory to store our device memory. > + * For ZONE_DEVICE coherent type we use the actual dpage to store the data > + * and ignore rpage. > */ > rpage = alloc_page(GFP_HIGHUSER); > if (!rpage) > @@ -623,12 +626,17 @@ static void dmirror_migrate_alloc_and_copy(struct migrate_vma *args, > * unallocated pte_none() or read-only zero page. > */ > spage = migrate_pfn_to_page(*src); > + if (spage && is_zone_device_page(spage)) > + pr_err("page already in device spage pfn: 0x%lx\n", > + page_to_pfn(spage)); > + WARN_ON(spage && is_zone_device_page(spage)); You can write WARN_ON inside the if-condition: if (WARN_ON(spage && is_zone_device_page(spage)) ... But I don't see why you need both pr_err and WARN_ON. You can add a custom message by using WARN instead of WARN_ON: WARN(spage && is_zone_device_page(spage), "page already in device spage pfn: 0x%lx\n", page_to_pfn(spage)); > > dpage = dmirror_devmem_alloc_page(mdevice); > if (!dpage) > continue; > > - rpage = dpage->zone_device_data; > + rpage = is_device_private_page(dpage) ? dpage->zone_device_data : > + dpage; > if (spage) > copy_highpage(rpage, spage); > else > @@ -640,8 +648,11 @@ static void dmirror_migrate_alloc_and_copy(struct migrate_vma *args, > * the simulated device memory and that page holds the pointer > * to the mirror. > */ > + rpage = dpage->zone_device_data; > rpage->zone_device_data = dmirror; > > + pr_debug("migrating from sys to dev pfn src: 0x%lx pfn dst: 0x%lx\n", > + page_to_pfn(spage), page_to_pfn(dpage)); > *dst = migrate_pfn(page_to_pfn(dpage)) | > MIGRATE_PFN_LOCKED; > if ((*src & MIGRATE_PFN_WRITE) || > @@ -721,10 +732,13 @@ static int dmirror_migrate_finalize_and_map(struct migrate_vma *args, > continue; > > /* > - * Store the page that holds the data so the page table > - * doesn't have to deal with ZONE_DEVICE private pages. > + * For ZONE_DEVICE private pages we store the page that > + * holds the data so the page table doesn't have to deal it. > + * For ZONE_DEVICE coherent pages we store the actual page, since > + * the CPU has coherent access to the page. > */ I find this explanation confusing. The comment in dmirror_devmem_alloc_page is much clearer. I think all we need here is that dpage->zone_device_data points to the backing page for device_private pages. Device_coherent struct pages don't have a backing page because they represent a real CPU-accessible page already. > - entry = dpage->zone_device_data; > + entry = is_device_private_page(dpage) ? dpage->zone_device_data : > + dpage; I see this in a few places. Maybe better to wrap that in a helper function or macro. Something like this: #define BACKING_PAGE(page) (is_device_private_page((page)) ? \ (page)->zone_device_data : (page)) > if (*dst & MIGRATE_PFN_WRITE) > entry = xa_tag_pointer(entry, DPT_XA_TAG_WRITE); > entry = xa_store(&dmirror->pt, pfn, entry, GFP_ATOMIC); > @@ -804,8 +818,110 @@ static int dmirror_exclusive(struct dmirror *dmirror, > return ret; > } > > -static int dmirror_migrate(struct dmirror *dmirror, > - struct hmm_dmirror_cmd *cmd) > +static vm_fault_t dmirror_devmem_fault_alloc_and_copy(struct migrate_vma *args, > + struct dmirror *dmirror) > +{ > + const unsigned long *src = args->src; > + unsigned long *dst = args->dst; > + unsigned long start = args->start; > + unsigned long end = args->end; > + unsigned long addr; > + > + for (addr = start; addr < end; addr += PAGE_SIZE, > + src++, dst++) { > + struct page *dpage, *spage; > + > + spage = migrate_pfn_to_page(*src); > + if (!spage || !(*src & MIGRATE_PFN_MIGRATE)) > + continue; > + > + WARN_ON(!is_device_page(spage)); > + spage = is_device_private_page(spage) ? spage->zone_device_data : > + spage; > + dpage = alloc_page_vma(GFP_HIGHUSER_MOVABLE, args->vma, addr); > + if (!dpage) > + continue; > + pr_debug("migrating from dev to sys pfn src: 0x%lx pfn dst: 0x%lx\n", > + page_to_pfn(spage), page_to_pfn(dpage)); > + > + lock_page(dpage); > + xa_erase(&dmirror->pt, addr >> PAGE_SHIFT); > + copy_highpage(dpage, spage); > + *dst = migrate_pfn(page_to_pfn(dpage)) | MIGRATE_PFN_LOCKED; > + if (*src & MIGRATE_PFN_WRITE) > + *dst |= MIGRATE_PFN_WRITE; > + } > + return 0; > +} > + > +static int dmirror_migrate_to_system(struct dmirror *dmirror, > + struct hmm_dmirror_cmd *cmd) > +{ > + unsigned long start, end, addr; > + unsigned long size = cmd->npages << PAGE_SHIFT; > + struct mm_struct *mm = dmirror->notifier.mm; > + struct vm_area_struct *vma; > + unsigned long src_pfns[64]; > + unsigned long dst_pfns[64]; > + struct migrate_vma args; > + unsigned long next; > + int ret; > + > + start = cmd->addr; > + end = start + size; > + if (end < start) > + return -EINVAL; > + > + /* Since the mm is for the mirrored process, get a reference first. */ > + if (!mmget_not_zero(mm)) > + return -EINVAL; > + > + mmap_read_lock(mm); > + for (addr = start; addr < end; addr = next) { > + vma = find_vma(mm, addr); > + if (!vma || addr < vma->vm_start || > + !(vma->vm_flags & VM_READ)) { > + ret = -EINVAL; > + goto out; > + } > + next = min(end, addr + (ARRAY_SIZE(src_pfns) << PAGE_SHIFT)); > + if (next > vma->vm_end) > + next = vma->vm_end; > + > + args.vma = vma; > + args.src = src_pfns; > + args.dst = dst_pfns; > + args.start = addr; > + args.end = next; > + args.pgmap_owner = dmirror->mdevice; > + args.flags = (dmirror->mdevice->zone_device_type == > + HMM_DMIRROR_MEMORY_DEVICE_PRIVATE) ? > + MIGRATE_VMA_SELECT_DEVICE_PRIVATE : > + MIGRATE_VMA_SELECT_DEVICE_COHERENT; > + > + ret = migrate_vma_setup(&args); > + if (ret) > + goto out; > + > + pr_debug("Migrating from device mem to sys mem\n"); > + dmirror_devmem_fault_alloc_and_copy(&args, dmirror); > + > + migrate_vma_pages(&args); > + migrate_vma_finalize(&args); > + } > + mmap_read_unlock(mm); > + mmput(mm); > + > + return ret; > + > +out: > + mmap_read_unlock(mm); > + mmput(mm); > + return ret; > +} > + > +static int dmirror_migrate_to_device(struct dmirror *dmirror, > + struct hmm_dmirror_cmd *cmd) > { > unsigned long start, end, addr; > unsigned long size = cmd->npages << PAGE_SHIFT; > @@ -849,6 +965,7 @@ static int dmirror_migrate(struct dmirror *dmirror, > if (ret) > goto out; > > + pr_debug("Migrating from sys mem to device mem\n"); > dmirror_migrate_alloc_and_copy(&args, dmirror); > migrate_vma_pages(&args); > dmirror_migrate_finalize_and_map(&args, dmirror); > @@ -857,7 +974,7 @@ static int dmirror_migrate(struct dmirror *dmirror, > mmap_read_unlock(mm); > mmput(mm); > > - /* Return the migrated data for verification. */ > + /* Return the migrated data for verification. only for pages in device zone */ > ret = dmirror_bounce_init(&bounce, start, size); > if (ret) > return ret; > @@ -894,9 +1011,15 @@ static void dmirror_mkentry(struct dmirror *dmirror, struct hmm_range *range, > } > > page = hmm_pfn_to_page(entry); > - if (is_device_private_page(page)) { > - /* Is the page migrated to this device or some other? */ > - if (dmirror->mdevice == dmirror_page_to_device(page)) > + if (is_device_page(page)) { > + /* Is page ZONE_DEVICE coherent? */ > + if (!is_device_private_page(page)) > + *perm = HMM_DMIRROR_PROT_DEV_COHERENT; Does it make sense to distinguish between DEV_COHERENT_LOCAL and DEV_COHERENT_REMOTE as well? > + /* > + * Is page ZONE_DEVICE private migrated to > + * this device or some other? > + */ > + else if (dmirror->mdevice == dmirror_page_to_device(page)) > *perm = HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL; > else > *perm = HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE; > @@ -1096,8 +1219,12 @@ static long dmirror_fops_unlocked_ioctl(struct file *filp, > ret = dmirror_write(dmirror, &cmd); > break; > > - case HMM_DMIRROR_MIGRATE: > - ret = dmirror_migrate(dmirror, &cmd); > + case HMM_DMIRROR_MIGRATE_TO_DEV: > + ret = dmirror_migrate_to_device(dmirror, &cmd); > + break; > + > + case HMM_DMIRROR_MIGRATE_TO_SYS: > + ret = dmirror_migrate_to_system(dmirror, &cmd); > break; > > case HMM_DMIRROR_EXCLUSIVE: > @@ -1152,38 +1279,6 @@ static void dmirror_devmem_free(struct page *page) > spin_unlock(&mdevice->lock); > } > > -static vm_fault_t dmirror_devmem_fault_alloc_and_copy(struct migrate_vma *args, > - struct dmirror *dmirror) > -{ > - const unsigned long *src = args->src; > - unsigned long *dst = args->dst; > - unsigned long start = args->start; > - unsigned long end = args->end; > - unsigned long addr; > - > - for (addr = start; addr < end; addr += PAGE_SIZE, > - src++, dst++) { > - struct page *dpage, *spage; > - > - spage = migrate_pfn_to_page(*src); > - if (!spage || !(*src & MIGRATE_PFN_MIGRATE)) > - continue; > - spage = spage->zone_device_data; > - > - dpage = alloc_page_vma(GFP_HIGHUSER_MOVABLE, args->vma, addr); > - if (!dpage) > - continue; > - > - lock_page(dpage); > - xa_erase(&dmirror->pt, addr >> PAGE_SHIFT); > - copy_highpage(dpage, spage); > - *dst = migrate_pfn(page_to_pfn(dpage)) | MIGRATE_PFN_LOCKED; > - if (*src & MIGRATE_PFN_WRITE) > - *dst |= MIGRATE_PFN_WRITE; > - } > - return 0; > -} > - > static vm_fault_t dmirror_devmem_fault(struct vm_fault *vmf) > { > struct migrate_vma args; > diff --git a/lib/test_hmm_uapi.h b/lib/test_hmm_uapi.h > index 77f81e6314eb..af15c35a90f4 100644 > --- a/lib/test_hmm_uapi.h > +++ b/lib/test_hmm_uapi.h > @@ -19,6 +19,7 @@ > * @npages: (in) number of pages to read/write > * @cpages: (out) number of pages copied > * @faults: (out) number of device page faults seen > + * @zone_device_type: (out) zone device memory type > */ > struct hmm_dmirror_cmd { > __u64 addr; > @@ -32,11 +33,12 @@ struct hmm_dmirror_cmd { > /* Expose the address space of the calling process through hmm device file */ > #define HMM_DMIRROR_READ _IOWR('H', 0x00, struct hmm_dmirror_cmd) > #define HMM_DMIRROR_WRITE _IOWR('H', 0x01, struct hmm_dmirror_cmd) > -#define HMM_DMIRROR_MIGRATE _IOWR('H', 0x02, struct hmm_dmirror_cmd) > -#define HMM_DMIRROR_SNAPSHOT _IOWR('H', 0x03, struct hmm_dmirror_cmd) > -#define HMM_DMIRROR_EXCLUSIVE _IOWR('H', 0x04, struct hmm_dmirror_cmd) > -#define HMM_DMIRROR_CHECK_EXCLUSIVE _IOWR('H', 0x05, struct hmm_dmirror_cmd) > -#define HMM_DMIRROR_GET_MEM_DEV_TYPE _IOWR('H', 0x06, struct hmm_dmirror_cmd) > +#define HMM_DMIRROR_MIGRATE_TO_DEV _IOWR('H', 0x02, struct hmm_dmirror_cmd) > +#define HMM_DMIRROR_MIGRATE_TO_SYS _IOWR('H', 0x03, struct hmm_dmirror_cmd) > +#define HMM_DMIRROR_SNAPSHOT _IOWR('H', 0x04, struct hmm_dmirror_cmd) > +#define HMM_DMIRROR_EXCLUSIVE _IOWR('H', 0x05, struct hmm_dmirror_cmd) > +#define HMM_DMIRROR_CHECK_EXCLUSIVE _IOWR('H', 0x06, struct hmm_dmirror_cmd) > +#define HMM_DMIRROR_GET_MEM_DEV_TYPE _IOWR('H', 0x07, struct hmm_dmirror_cmd) > > /* > * Values returned in hmm_dmirror_cmd.ptr for HMM_DMIRROR_SNAPSHOT. > @@ -51,6 +53,8 @@ struct hmm_dmirror_cmd { > * device the ioctl() is made > * HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE: Migrated device private page on some > * other device > + * HMM_DMIRROR_PROT_DEV_COHERENT: Migrate device coherent page on the device > + * the ioctl() is made > */ > enum { > HMM_DMIRROR_PROT_ERROR = 0xFF, > @@ -62,6 +66,7 @@ enum { > HMM_DMIRROR_PROT_ZERO = 0x10, > HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL = 0x20, > HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE = 0x30, > + HMM_DMIRROR_PROT_DEV_COHERENT = 0x40, Does it make sense to distinguish between DEV_COHERENT_LOCAL and DEV_COHERENT_REMOTE as well? Regards, Felix > }; > > enum {
diff --git a/lib/test_hmm.c b/lib/test_hmm.c index 45334df28d7b..9e2cc0cd4412 100644 --- a/lib/test_hmm.c +++ b/lib/test_hmm.c @@ -471,6 +471,7 @@ static int dmirror_allocate_chunk(struct dmirror_device *mdevice, unsigned long pfn_first; unsigned long pfn_last; void *ptr; + int ret = -ENOMEM; devmem = kzalloc(sizeof(*devmem), GFP_KERNEL); if (!devmem) @@ -553,7 +554,7 @@ static int dmirror_allocate_chunk(struct dmirror_device *mdevice, } spin_unlock(&mdevice->lock); - return true; + return 0; err_release: mutex_unlock(&mdevice->devmem_lock); @@ -562,7 +563,7 @@ static int dmirror_allocate_chunk(struct dmirror_device *mdevice, err_devmem: kfree(devmem); - return false; + return ret; } static struct page *dmirror_devmem_alloc_page(struct dmirror_device *mdevice) @@ -571,8 +572,10 @@ static struct page *dmirror_devmem_alloc_page(struct dmirror_device *mdevice) struct page *rpage; /* - * This is a fake device so we alloc real system memory to store - * our device memory. + * For ZONE_DEVICE private type, this is a fake device so we alloc real + * system memory to store our device memory. + * For ZONE_DEVICE coherent type we use the actual dpage to store the data + * and ignore rpage. */ rpage = alloc_page(GFP_HIGHUSER); if (!rpage) @@ -623,12 +626,17 @@ static void dmirror_migrate_alloc_and_copy(struct migrate_vma *args, * unallocated pte_none() or read-only zero page. */ spage = migrate_pfn_to_page(*src); + if (spage && is_zone_device_page(spage)) + pr_err("page already in device spage pfn: 0x%lx\n", + page_to_pfn(spage)); + WARN_ON(spage && is_zone_device_page(spage)); dpage = dmirror_devmem_alloc_page(mdevice); if (!dpage) continue; - rpage = dpage->zone_device_data; + rpage = is_device_private_page(dpage) ? dpage->zone_device_data : + dpage; if (spage) copy_highpage(rpage, spage); else @@ -640,8 +648,11 @@ static void dmirror_migrate_alloc_and_copy(struct migrate_vma *args, * the simulated device memory and that page holds the pointer * to the mirror. */ + rpage = dpage->zone_device_data; rpage->zone_device_data = dmirror; + pr_debug("migrating from sys to dev pfn src: 0x%lx pfn dst: 0x%lx\n", + page_to_pfn(spage), page_to_pfn(dpage)); *dst = migrate_pfn(page_to_pfn(dpage)) | MIGRATE_PFN_LOCKED; if ((*src & MIGRATE_PFN_WRITE) || @@ -721,10 +732,13 @@ static int dmirror_migrate_finalize_and_map(struct migrate_vma *args, continue; /* - * Store the page that holds the data so the page table - * doesn't have to deal with ZONE_DEVICE private pages. + * For ZONE_DEVICE private pages we store the page that + * holds the data so the page table doesn't have to deal it. + * For ZONE_DEVICE coherent pages we store the actual page, since + * the CPU has coherent access to the page. */ - entry = dpage->zone_device_data; + entry = is_device_private_page(dpage) ? dpage->zone_device_data : + dpage; if (*dst & MIGRATE_PFN_WRITE) entry = xa_tag_pointer(entry, DPT_XA_TAG_WRITE); entry = xa_store(&dmirror->pt, pfn, entry, GFP_ATOMIC); @@ -804,8 +818,110 @@ static int dmirror_exclusive(struct dmirror *dmirror, return ret; } -static int dmirror_migrate(struct dmirror *dmirror, - struct hmm_dmirror_cmd *cmd) +static vm_fault_t dmirror_devmem_fault_alloc_and_copy(struct migrate_vma *args, + struct dmirror *dmirror) +{ + const unsigned long *src = args->src; + unsigned long *dst = args->dst; + unsigned long start = args->start; + unsigned long end = args->end; + unsigned long addr; + + for (addr = start; addr < end; addr += PAGE_SIZE, + src++, dst++) { + struct page *dpage, *spage; + + spage = migrate_pfn_to_page(*src); + if (!spage || !(*src & MIGRATE_PFN_MIGRATE)) + continue; + + WARN_ON(!is_device_page(spage)); + spage = is_device_private_page(spage) ? spage->zone_device_data : + spage; + dpage = alloc_page_vma(GFP_HIGHUSER_MOVABLE, args->vma, addr); + if (!dpage) + continue; + pr_debug("migrating from dev to sys pfn src: 0x%lx pfn dst: 0x%lx\n", + page_to_pfn(spage), page_to_pfn(dpage)); + + lock_page(dpage); + xa_erase(&dmirror->pt, addr >> PAGE_SHIFT); + copy_highpage(dpage, spage); + *dst = migrate_pfn(page_to_pfn(dpage)) | MIGRATE_PFN_LOCKED; + if (*src & MIGRATE_PFN_WRITE) + *dst |= MIGRATE_PFN_WRITE; + } + return 0; +} + +static int dmirror_migrate_to_system(struct dmirror *dmirror, + struct hmm_dmirror_cmd *cmd) +{ + unsigned long start, end, addr; + unsigned long size = cmd->npages << PAGE_SHIFT; + struct mm_struct *mm = dmirror->notifier.mm; + struct vm_area_struct *vma; + unsigned long src_pfns[64]; + unsigned long dst_pfns[64]; + struct migrate_vma args; + unsigned long next; + int ret; + + start = cmd->addr; + end = start + size; + if (end < start) + return -EINVAL; + + /* Since the mm is for the mirrored process, get a reference first. */ + if (!mmget_not_zero(mm)) + return -EINVAL; + + mmap_read_lock(mm); + for (addr = start; addr < end; addr = next) { + vma = find_vma(mm, addr); + if (!vma || addr < vma->vm_start || + !(vma->vm_flags & VM_READ)) { + ret = -EINVAL; + goto out; + } + next = min(end, addr + (ARRAY_SIZE(src_pfns) << PAGE_SHIFT)); + if (next > vma->vm_end) + next = vma->vm_end; + + args.vma = vma; + args.src = src_pfns; + args.dst = dst_pfns; + args.start = addr; + args.end = next; + args.pgmap_owner = dmirror->mdevice; + args.flags = (dmirror->mdevice->zone_device_type == + HMM_DMIRROR_MEMORY_DEVICE_PRIVATE) ? + MIGRATE_VMA_SELECT_DEVICE_PRIVATE : + MIGRATE_VMA_SELECT_DEVICE_COHERENT; + + ret = migrate_vma_setup(&args); + if (ret) + goto out; + + pr_debug("Migrating from device mem to sys mem\n"); + dmirror_devmem_fault_alloc_and_copy(&args, dmirror); + + migrate_vma_pages(&args); + migrate_vma_finalize(&args); + } + mmap_read_unlock(mm); + mmput(mm); + + return ret; + +out: + mmap_read_unlock(mm); + mmput(mm); + return ret; +} + +static int dmirror_migrate_to_device(struct dmirror *dmirror, + struct hmm_dmirror_cmd *cmd) { unsigned long start, end, addr; unsigned long size = cmd->npages << PAGE_SHIFT; @@ -849,6 +965,7 @@ static int dmirror_migrate(struct dmirror *dmirror, if (ret) goto out; + pr_debug("Migrating from sys mem to device mem\n"); dmirror_migrate_alloc_and_copy(&args, dmirror); migrate_vma_pages(&args); dmirror_migrate_finalize_and_map(&args, dmirror); @@ -857,7 +974,7 @@ static int dmirror_migrate(struct dmirror *dmirror, mmap_read_unlock(mm); mmput(mm); - /* Return the migrated data for verification. */ + /* Return the migrated data for verification. only for pages in device zone */ ret = dmirror_bounce_init(&bounce, start, size); if (ret) return ret; @@ -894,9 +1011,15 @@ static void dmirror_mkentry(struct dmirror *dmirror, struct hmm_range *range, } page = hmm_pfn_to_page(entry); - if (is_device_private_page(page)) { - /* Is the page migrated to this device or some other? */ - if (dmirror->mdevice == dmirror_page_to_device(page)) + if (is_device_page(page)) { + /* Is page ZONE_DEVICE coherent? */ + if (!is_device_private_page(page)) + *perm = HMM_DMIRROR_PROT_DEV_COHERENT; + /* + * Is page ZONE_DEVICE private migrated to + * this device or some other? + */ + else if (dmirror->mdevice == dmirror_page_to_device(page)) *perm = HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL; else *perm = HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE; @@ -1096,8 +1219,12 @@ static long dmirror_fops_unlocked_ioctl(struct file *filp, ret = dmirror_write(dmirror, &cmd); break; - case HMM_DMIRROR_MIGRATE: - ret = dmirror_migrate(dmirror, &cmd); + case HMM_DMIRROR_MIGRATE_TO_DEV: + ret = dmirror_migrate_to_device(dmirror, &cmd); + break; + + case HMM_DMIRROR_MIGRATE_TO_SYS: + ret = dmirror_migrate_to_system(dmirror, &cmd); break; case HMM_DMIRROR_EXCLUSIVE: @@ -1152,38 +1279,6 @@ static void dmirror_devmem_free(struct page *page) spin_unlock(&mdevice->lock); } -static vm_fault_t dmirror_devmem_fault_alloc_and_copy(struct migrate_vma *args, - struct dmirror *dmirror) -{ - const unsigned long *src = args->src; - unsigned long *dst = args->dst; - unsigned long start = args->start; - unsigned long end = args->end; - unsigned long addr; - - for (addr = start; addr < end; addr += PAGE_SIZE, - src++, dst++) { - struct page *dpage, *spage; - - spage = migrate_pfn_to_page(*src); - if (!spage || !(*src & MIGRATE_PFN_MIGRATE)) - continue; - spage = spage->zone_device_data; - - dpage = alloc_page_vma(GFP_HIGHUSER_MOVABLE, args->vma, addr); - if (!dpage) - continue; - - lock_page(dpage); - xa_erase(&dmirror->pt, addr >> PAGE_SHIFT); - copy_highpage(dpage, spage); - *dst = migrate_pfn(page_to_pfn(dpage)) | MIGRATE_PFN_LOCKED; - if (*src & MIGRATE_PFN_WRITE) - *dst |= MIGRATE_PFN_WRITE; - } - return 0; -} - static vm_fault_t dmirror_devmem_fault(struct vm_fault *vmf) { struct migrate_vma args; diff --git a/lib/test_hmm_uapi.h b/lib/test_hmm_uapi.h index 77f81e6314eb..af15c35a90f4 100644 --- a/lib/test_hmm_uapi.h +++ b/lib/test_hmm_uapi.h @@ -19,6 +19,7 @@ * @npages: (in) number of pages to read/write * @cpages: (out) number of pages copied * @faults: (out) number of device page faults seen + * @zone_device_type: (out) zone device memory type */ struct hmm_dmirror_cmd { __u64 addr; @@ -32,11 +33,12 @@ struct hmm_dmirror_cmd { /* Expose the address space of the calling process through hmm device file */ #define HMM_DMIRROR_READ _IOWR('H', 0x00, struct hmm_dmirror_cmd) #define HMM_DMIRROR_WRITE _IOWR('H', 0x01, struct hmm_dmirror_cmd) -#define HMM_DMIRROR_MIGRATE _IOWR('H', 0x02, struct hmm_dmirror_cmd) -#define HMM_DMIRROR_SNAPSHOT _IOWR('H', 0x03, struct hmm_dmirror_cmd) -#define HMM_DMIRROR_EXCLUSIVE _IOWR('H', 0x04, struct hmm_dmirror_cmd) -#define HMM_DMIRROR_CHECK_EXCLUSIVE _IOWR('H', 0x05, struct hmm_dmirror_cmd) -#define HMM_DMIRROR_GET_MEM_DEV_TYPE _IOWR('H', 0x06, struct hmm_dmirror_cmd) +#define HMM_DMIRROR_MIGRATE_TO_DEV _IOWR('H', 0x02, struct hmm_dmirror_cmd) +#define HMM_DMIRROR_MIGRATE_TO_SYS _IOWR('H', 0x03, struct hmm_dmirror_cmd) +#define HMM_DMIRROR_SNAPSHOT _IOWR('H', 0x04, struct hmm_dmirror_cmd) +#define HMM_DMIRROR_EXCLUSIVE _IOWR('H', 0x05, struct hmm_dmirror_cmd) +#define HMM_DMIRROR_CHECK_EXCLUSIVE _IOWR('H', 0x06, struct hmm_dmirror_cmd) +#define HMM_DMIRROR_GET_MEM_DEV_TYPE _IOWR('H', 0x07, struct hmm_dmirror_cmd) /* * Values returned in hmm_dmirror_cmd.ptr for HMM_DMIRROR_SNAPSHOT. @@ -51,6 +53,8 @@ struct hmm_dmirror_cmd { * device the ioctl() is made * HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE: Migrated device private page on some * other device + * HMM_DMIRROR_PROT_DEV_COHERENT: Migrate device coherent page on the device + * the ioctl() is made */ enum { HMM_DMIRROR_PROT_ERROR = 0xFF, @@ -62,6 +66,7 @@ enum { HMM_DMIRROR_PROT_ZERO = 0x10, HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL = 0x20, HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE = 0x30, + HMM_DMIRROR_PROT_DEV_COHERENT = 0x40, }; enum {
Device Coherent type uses device memory that is coherently accesible by the CPU. This could be shown as SP (special purpose) memory range at the BIOS-e820 memory enumeration. If no SP memory is supported in system, this could be faked by setting CONFIG_EFI_FAKE_MEMMAP. Currently, test_hmm only supports two different SP ranges of at least 256MB size. This could be specified in the kernel parameter variable efi_fake_mem. Ex. Two SP ranges of 1GB starting at 0x100000000 & 0x140000000 physical address. Ex. efi_fake_mem=1G@0x100000000:0x40000,1G@0x140000000:0x40000 Signed-off-by: Alex Sierra <alex.sierra@amd.com> --- lib/test_hmm.c | 191 +++++++++++++++++++++++++++++++++----------- lib/test_hmm_uapi.h | 15 ++-- 2 files changed, 153 insertions(+), 53 deletions(-)