diff options
| -rw-r--r-- | include/linux/hmm.h | 31 | ||||
| -rw-r--r-- | mm/hmm.c | 33 |
2 files changed, 44 insertions, 20 deletions
diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 42b1ae915915..c6fb869a81c0 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -274,14 +274,29 @@ static inline uint64_t hmm_pfn_from_pfn(const struct hmm_range *range, struct hmm_mirror; /* - * enum hmm_update_type - type of update + * enum hmm_update_event - type of update * @HMM_UPDATE_INVALIDATE: invalidate range (no indication as to why) */ -enum hmm_update_type { +enum hmm_update_event { HMM_UPDATE_INVALIDATE, }; /* + * struct hmm_update - HMM update informations for callback + * + * @start: virtual start address of the range to update + * @end: virtual end address of the range to update + * @event: event triggering the update (what is happening) + * @blockable: can the callback block/sleep ? + */ +struct hmm_update { + unsigned long start; + unsigned long end; + enum hmm_update_event event; + bool blockable; +}; + +/* * struct hmm_mirror_ops - HMM mirror device operations callback * * @update: callback to update range on a device @@ -300,9 +315,9 @@ struct hmm_mirror_ops { /* sync_cpu_device_pagetables() - synchronize page tables * * @mirror: pointer to struct hmm_mirror - * @update_type: type of update that occurred to the CPU page table - * @start: virtual start address of the range to update - * @end: virtual end address of the range to update + * @update: update informations (see struct hmm_update) + * Returns: -EAGAIN if update.blockable false and callback need to + * block, 0 otherwise. * * This callback ultimately originates from mmu_notifiers when the CPU * page table is updated. The device driver must update its page table @@ -313,10 +328,8 @@ struct hmm_mirror_ops { * page tables are completely updated (TLBs flushed, etc); this is a * synchronous call. */ - void (*sync_cpu_device_pagetables)(struct hmm_mirror *mirror, - enum hmm_update_type update_type, - unsigned long start, - unsigned long end); + int (*sync_cpu_device_pagetables)(struct hmm_mirror *mirror, + const struct hmm_update *update); }; /* @@ -126,10 +126,8 @@ void hmm_mm_destroy(struct mm_struct *mm) kfree(mm->hmm); } -static void hmm_invalidate_range(struct hmm *hmm, - enum hmm_update_type action, - unsigned long start, - unsigned long end) +static int hmm_invalidate_range(struct hmm *hmm, + const struct hmm_update *update) { struct hmm_mirror *mirror; struct hmm_range *range; @@ -138,22 +136,30 @@ static void hmm_invalidate_range(struct hmm *hmm, list_for_each_entry(range, &hmm->ranges, list) { unsigned long addr, idx, npages; - if (end < range->start || start >= range->end) + if (update->end < range->start || update->start >= range->end) continue; range->valid = false; - addr = max(start, range->start); + addr = max(update->start, range->start); idx = (addr - range->start) >> PAGE_SHIFT; - npages = (min(range->end, end) - addr) >> PAGE_SHIFT; + npages = (min(range->end, update->end) - addr) >> PAGE_SHIFT; memset(&range->pfns[idx], 0, sizeof(*range->pfns) * npages); } spin_unlock(&hmm->lock); down_read(&hmm->mirrors_sem); - list_for_each_entry(mirror, &hmm->mirrors, list) - mirror->ops->sync_cpu_device_pagetables(mirror, action, - start, end); + list_for_each_entry(mirror, &hmm->mirrors, list) { + int ret; + + ret = mirror->ops->sync_cpu_device_pagetables(mirror, update); + if (!update->blockable && ret == -EAGAIN) { + up_read(&hmm->mirrors_sem); + return -EAGAIN; + } + } up_read(&hmm->mirrors_sem); + + return 0; } static void hmm_release(struct mmu_notifier *mn, struct mm_struct *mm) @@ -202,11 +208,16 @@ static void hmm_invalidate_range_end(struct mmu_notifier *mn, unsigned long start, unsigned long end) { + struct hmm_update update; struct hmm *hmm = mm->hmm; VM_BUG_ON(!hmm); - hmm_invalidate_range(mm->hmm, HMM_UPDATE_INVALIDATE, start, end); + update.start = start; + update.end = end; + update.event = HMM_UPDATE_INVALIDATE; + update.blockable = true; + hmm_invalidate_range(hmm, &update); } static const struct mmu_notifier_ops hmm_mmu_notifier_ops = { |