cregit-Linux how code gets into the kernel

Release 4.14 arch/s390/mm/gmap.c

Directory: arch/s390/mm
/*
 *  KVM guest address space mapping code
 *
 *    Copyright IBM Corp. 2007, 2016
 *    Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
 */

#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/swapops.h>
#include <linux/ksm.h>
#include <linux/mman.h>

#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/gmap.h>
#include <asm/tlb.h>


#define GMAP_SHADOW_FAKE_TABLE 1ULL

/**
 * gmap_alloc - allocate and initialize a guest address space
 * @mm: pointer to the parent mm_struct
 * @limit: maximum address of the gmap address space
 *
 * Returns a guest address space structure.
 */

static struct gmap *gmap_alloc(unsigned long limit) { struct gmap *gmap; struct page *page; unsigned long *table; unsigned long etype, atype; if (limit < _REGION3_SIZE) { limit = _REGION3_SIZE - 1; atype = _ASCE_TYPE_SEGMENT; etype = _SEGMENT_ENTRY_EMPTY; } else if (limit < _REGION2_SIZE) { limit = _REGION2_SIZE - 1; atype = _ASCE_TYPE_REGION3; etype = _REGION3_ENTRY_EMPTY; } else if (limit < _REGION1_SIZE) { limit = _REGION1_SIZE - 1; atype = _ASCE_TYPE_REGION2; etype = _REGION2_ENTRY_EMPTY; } else { limit = -1UL; atype = _ASCE_TYPE_REGION1; etype = _REGION1_ENTRY_EMPTY; } gmap = kzalloc(sizeof(struct gmap), GFP_KERNEL); if (!gmap) goto out; INIT_LIST_HEAD(&gmap->crst_list); INIT_LIST_HEAD(&gmap->children); INIT_LIST_HEAD(&gmap->pt_list); INIT_RADIX_TREE(&gmap->guest_to_host, GFP_KERNEL); INIT_RADIX_TREE(&gmap->host_to_guest, GFP_ATOMIC); INIT_RADIX_TREE(&gmap->host_to_rmap, GFP_ATOMIC); spin_lock_init(&gmap->guest_table_lock); spin_lock_init(&gmap->shadow_lock); atomic_set(&gmap->ref_count, 1); page = alloc_pages(GFP_KERNEL, CRST_ALLOC_ORDER); if (!page) goto out_free; page->index = 0; list_add(&page->lru, &gmap->crst_list); table = (unsigned long *) page_to_phys(page); crst_table_init(table, etype); gmap->table = table; gmap->asce = atype | _ASCE_TABLE_LENGTH | _ASCE_USER_BITS | __pa(table); gmap->asce_end = limit; return gmap; out_free: kfree(gmap); out: return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky30897.78%375.00%
Heiko Carstens72.22%125.00%
Total315100.00%4100.00%

/** * gmap_create - create a guest address space * @mm: pointer to the parent mm_struct * @limit: maximum size of the gmap address space * * Returns a guest address space structure. */
struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit) { struct gmap *gmap; unsigned long gmap_asce; gmap = gmap_alloc(limit); if (!gmap) return NULL; gmap->mm = mm; spin_lock(&mm->context.lock); list_add_rcu(&gmap->list, &mm->context.gmap_list); if (list_is_singular(&mm->context.gmap_list)) gmap_asce = gmap->asce; else gmap_asce = -1UL; WRITE_ONCE(mm->context.gmap_asce, gmap_asce); spin_unlock(&mm->context.lock); return gmap; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky119100.00%5100.00%
Total119100.00%5100.00%

EXPORT_SYMBOL_GPL(gmap_create);
static void gmap_flush_tlb(struct gmap *gmap) { if (MACHINE_HAS_IDTE) __tlb_flush_idte(gmap->asce); else __tlb_flush_global(); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky2596.15%150.00%
David Hildenbrand13.85%150.00%
Total26100.00%2100.00%


static void gmap_radix_tree_free(struct radix_tree_root *root) { struct radix_tree_iter iter; unsigned long indices[16]; unsigned long index; void __rcu **slot; int i, nr; /* A radix tree is freed by deleting all of its entries */ index = 0; do { nr = 0; radix_tree_for_each_slot(slot, root, &iter, index) { indices[nr] = iter.index; if (++nr == 16) break; } for (i = 0; i < nr; i++) { index = indices[i]; radix_tree_delete(root, index); } } while (nr > 0); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky11399.12%150.00%
Heiko Carstens10.88%150.00%
Total114100.00%2100.00%


static void gmap_rmap_radix_tree_free(struct radix_tree_root *root) { struct gmap_rmap *rmap, *rnext, *head; struct radix_tree_iter iter; unsigned long indices[16]; unsigned long index; void __rcu **slot; int i, nr; /* A radix tree is freed by deleting all of its entries */ index = 0; do { nr = 0; radix_tree_for_each_slot(slot, root, &iter, index) { indices[nr] = iter.index; if (++nr == 16) break; } for (i = 0; i < nr; i++) { index = indices[i]; head = radix_tree_delete(root, index); gmap_for_each_rmap_safe(rmap, rnext, head) kfree(rmap); } } while (nr > 0); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky13999.29%266.67%
Heiko Carstens10.71%133.33%
Total140100.00%3100.00%

/** * gmap_free - free a guest address space * @gmap: pointer to the guest address space structure * * No locks required. There are no references to this gmap anymore. */
static void gmap_free(struct gmap *gmap) { struct page *page, *next; /* Flush tlb of all gmaps (if not already done for shadows) */ if (!(gmap_is_shadow(gmap) && gmap->removed)) gmap_flush_tlb(gmap); /* Free all segment & region tables. */ list_for_each_entry_safe(page, next, &gmap->crst_list, lru) __free_pages(page, CRST_ALLOC_ORDER); gmap_radix_tree_free(&gmap->guest_to_host); gmap_radix_tree_free(&gmap->host_to_guest); /* Free additional data for a shadow gmap */ if (gmap_is_shadow(gmap)) { /* Free all page tables. */ list_for_each_entry_safe(page, next, &gmap->pt_list, lru) page_table_free_pgste(page); gmap_rmap_radix_tree_free(&gmap->host_to_rmap); /* Release reference to the parent */ gmap_put(gmap->parent); } kfree(gmap); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky9982.50%360.00%
David Hildenbrand2016.67%120.00%
Heiko Carstens10.83%120.00%
Total120100.00%5100.00%

/** * gmap_get - increase reference counter for guest address space * @gmap: pointer to the guest address space structure * * Returns the gmap pointer */
struct gmap *gmap_get(struct gmap *gmap) { atomic_inc(&gmap->ref_count); return gmap; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky23100.00%2100.00%
Total23100.00%2100.00%

EXPORT_SYMBOL_GPL(gmap_get); /** * gmap_put - decrease reference counter for guest address space * @gmap: pointer to the guest address space structure * * If the reference counter reaches zero the guest address space is freed. */
void gmap_put(struct gmap *gmap) { if (atomic_dec_return(&gmap->ref_count) == 0) gmap_free(gmap); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky27100.00%2100.00%
Total27100.00%2100.00%

EXPORT_SYMBOL_GPL(gmap_put); /** * gmap_remove - remove a guest address space but do not free it yet * @gmap: pointer to the guest address space structure */
void gmap_remove(struct gmap *gmap) { struct gmap *sg, *next; unsigned long gmap_asce; /* Remove all shadow gmaps linked to this gmap */ if (!list_empty(&gmap->children)) { spin_lock(&gmap->shadow_lock); list_for_each_entry_safe(sg, next, &gmap->children, list) { list_del(&sg->list); gmap_put(sg); } spin_unlock(&gmap->shadow_lock); } /* Remove gmap from the pre-mm list */ spin_lock(&gmap->mm->context.lock); list_del_rcu(&gmap->list); if (list_empty(&gmap->mm->context.gmap_list)) gmap_asce = 0; else if (list_is_singular(&gmap->mm->context.gmap_list)) gmap_asce = list_first_entry(&gmap->mm->context.gmap_list, struct gmap, list)->asce; else gmap_asce = -1UL; WRITE_ONCE(gmap->mm->context.gmap_asce, gmap_asce); spin_unlock(&gmap->mm->context.lock); synchronize_rcu(); /* Put reference */ gmap_put(gmap); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky192100.00%6100.00%
Total192100.00%6100.00%

EXPORT_SYMBOL_GPL(gmap_remove); /** * gmap_enable - switch primary space to the guest address space * @gmap: pointer to the guest address space structure */
void gmap_enable(struct gmap *gmap) { S390_lowcore.gmap = (unsigned long) gmap; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky20100.00%1100.00%
Total20100.00%1100.00%

EXPORT_SYMBOL_GPL(gmap_enable); /** * gmap_disable - switch back to the standard primary address space * @gmap: pointer to the guest address space structure */
void gmap_disable(struct gmap *gmap) { S390_lowcore.gmap = 0UL; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky16100.00%1100.00%
Total16100.00%1100.00%

EXPORT_SYMBOL_GPL(gmap_disable); /** * gmap_get_enabled - get a pointer to the currently enabled gmap * * Returns a pointer to the currently enabled gmap. 0 if none is enabled. */
struct gmap *gmap_get_enabled(void) { return (struct gmap *) S390_lowcore.gmap; }

Contributors

PersonTokensPropCommitsCommitProp
David Hildenbrand19100.00%1100.00%
Total19100.00%1100.00%

EXPORT_SYMBOL_GPL(gmap_get_enabled); /* * gmap_alloc_table is assumed to be called with mmap_sem held */
static int gmap_alloc_table(struct gmap *gmap, unsigned long *table, unsigned long init, unsigned long gaddr) { struct page *page; unsigned long *new; /* since we dont free the gmap table until gmap_free we can unlock */ page = alloc_pages(GFP_KERNEL, CRST_ALLOC_ORDER); if (!page) return -ENOMEM; new = (unsigned long *) page_to_phys(page); crst_table_init(new, init); spin_lock(&gmap->guest_table_lock); if (*table & _REGION_ENTRY_INVALID) { list_add(&page->lru, &gmap->crst_list); *table = (unsigned long) new | _REGION_ENTRY_LENGTH | (*table & _REGION_ENTRY_TYPE_MASK); page->index = gaddr; page = NULL; } spin_unlock(&gmap->guest_table_lock); if (page) __free_pages(page, CRST_ALLOC_ORDER); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky15098.68%266.67%
Heiko Carstens21.32%133.33%
Total152100.00%3100.00%

/** * __gmap_segment_gaddr - find virtual address from segment pointer * @entry: pointer to a segment table entry in the guest address space * * Returns the virtual address in the guest address space for the segment */
static unsigned long __gmap_segment_gaddr(unsigned long *entry) { struct page *page; unsigned long offset, mask; offset = (unsigned long) entry / sizeof(unsigned long); offset = (offset & (PTRS_PER_PMD - 1)) * PMD_SIZE; mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); page = virt_to_page((void *)((unsigned long) entry & mask)); return page->index + offset; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky91100.00%1100.00%
Total91100.00%1100.00%

/** * __gmap_unlink_by_vmaddr - unlink a single segment via a host address * @gmap: pointer to the guest address space structure * @vmaddr: address in the host process address space * * Returns 1 if a TLB flush is required */
static int __gmap_unlink_by_vmaddr(struct gmap *gmap, unsigned long vmaddr) { unsigned long *entry; int flush = 0; BUG_ON(gmap_is_shadow(gmap)); spin_lock(&gmap->guest_table_lock); entry = radix_tree_delete(&gmap->host_to_guest, vmaddr >> PMD_SHIFT); if (entry) { flush = (*entry != _SEGMENT_ENTRY_EMPTY); *entry = _SEGMENT_ENTRY_EMPTY; } spin_unlock(&gmap->guest_table_lock); return flush; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky8497.67%266.67%
Dominik Dingel22.33%133.33%
Total86100.00%3100.00%

/** * __gmap_unmap_by_gaddr - unmap a single segment via a guest address * @gmap: pointer to the guest address space structure * @gaddr: address in the guest address space * * Returns 1 if a TLB flush is required */
static int __gmap_unmap_by_gaddr(struct gmap *gmap, unsigned long gaddr) { unsigned long vmaddr; vmaddr = (unsigned long) radix_tree_delete(&gmap->guest_to_host, gaddr >> PMD_SHIFT); return vmaddr ? __gmap_unlink_by_vmaddr(gmap, vmaddr) : 0; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky49100.00%1100.00%
Total49100.00%1100.00%

/** * gmap_unmap_segment - unmap segment from the guest address space * @gmap: pointer to the guest address space structure * @to: address in the guest address space * @len: length of the memory area to unmap * * Returns 0 if the unmap succeeded, -EINVAL if not. */
int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len) { unsigned long off; int flush; BUG_ON(gmap_is_shadow(gmap)); if ((to | len) & (PMD_SIZE - 1)) return -EINVAL; if (len == 0 || to + len < to) return -EINVAL; flush = 0; down_write(&gmap->mm->mmap_sem); for (off = 0; off < len; off += PMD_SIZE) flush |= __gmap_unmap_by_gaddr(gmap, to + off); up_write(&gmap->mm->mmap_sem); if (flush) gmap_flush_tlb(gmap); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky128100.00%2100.00%
Total128100.00%2100.00%

EXPORT_SYMBOL_GPL(gmap_unmap_segment); /** * gmap_map_segment - map a segment to the guest address space * @gmap: pointer to the guest address space structure * @from: source address in the parent address space * @to: target address in the guest address space * @len: length of the memory area to map * * Returns 0 if the mmap succeeded, -EINVAL or -ENOMEM if not. */
int gmap_map_segment(struct gmap *gmap, unsigned long from, unsigned long to, unsigned long len) { unsigned long off; int flush; BUG_ON(gmap_is_shadow(gmap)); if ((from | to | len) & (PMD_SIZE - 1)) return -EINVAL; if (len == 0 || from + len < from || to + len < to || from + len - 1 > TASK_SIZE_MAX || to + len - 1 > gmap->asce_end) return -EINVAL; flush = 0; down_write(&gmap->mm->mmap_sem); for (off = 0; off < len; off += PMD_SIZE) { /* Remove old translation */ flush |= __gmap_unmap_by_gaddr(gmap, to + off); /* Store new translation */ if (radix_tree_insert(&gmap->guest_to_host, (to + off) >> PMD_SHIFT, (void *) from + off)) break; } up_write(&gmap->mm->mmap_sem); if (flush) gmap_flush_tlb(gmap); if (off >= len) return 0; gmap_unmap_segment(gmap, to, len); return -ENOMEM; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky20498.08%375.00%
Christian Bornträger41.92%125.00%
Total208100.00%4100.00%

EXPORT_SYMBOL_GPL(gmap_map_segment); /** * __gmap_translate - translate a guest address to a user space address * @gmap: pointer to guest mapping meta data structure * @gaddr: guest address * * Returns user space address which corresponds to the guest address or * -EFAULT if no such mapping exists. * This function does not establish potentially missing page table entries. * The mmap_sem of the mm that belongs to the address space must be held * when this function gets called. * * Note: Can also be called for shadow gmaps. */
unsigned long __gmap_translate(struct gmap *gmap, unsigned long gaddr) { unsigned long vmaddr; vmaddr = (unsigned long) radix_tree_lookup(&gmap->guest_to_host, gaddr >> PMD_SHIFT); /* Note: guest_to_host is empty for a shadow gmap */ return vmaddr ? (vmaddr | (gaddr & ~PMD_MASK)) : -EFAULT; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky55100.00%2100.00%
Total55100.00%2100.00%

EXPORT_SYMBOL_GPL(__gmap_translate); /** * gmap_translate - translate a guest address to a user space address * @gmap: pointer to guest mapping meta data structure * @gaddr: guest address * * Returns user space address which corresponds to the guest address or * -EFAULT if no such mapping exists. * This function does not establish potentially missing page table entries. */
unsigned long gmap_translate(struct gmap *gmap, unsigned long gaddr) { unsigned long rc; down_read(&gmap->mm->mmap_sem); rc = __gmap_translate(gmap, gaddr); up_read(&gmap->mm->mmap_sem); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky51100.00%1100.00%
Total51100.00%1100.00%

EXPORT_SYMBOL_GPL(gmap_translate); /** * gmap_unlink - disconnect a page table from the gmap shadow tables * @gmap: pointer to guest mapping meta data structure * @table: pointer to the host page table * @vmaddr: vm address associated with the host page table */
void gmap_unlink(struct mm_struct *mm, unsigned long *table, unsigned long vmaddr) { struct gmap *gmap; int flush; rcu_read_lock(); list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { flush = __gmap_unlink_by_vmaddr(gmap, vmaddr); if (flush) gmap_flush_tlb(gmap); } rcu_read_unlock(); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky61100.00%2100.00%
Total61100.00%2100.00%

/** * gmap_link - set up shadow page tables to connect a host to a guest address * @gmap: pointer to guest mapping meta data structure * @gaddr: guest address * @vmaddr: vm address * * Returns 0 on success, -ENOMEM for out of memory conditions, and -EFAULT * if the vm address is already mapped to a different guest segment. * The mmap_sem of the mm that belongs to the address space must be held * when this function gets called. */
int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr) { struct mm_struct *mm; unsigned long *table; spinlock_t *ptl; pgd_t *pgd; p4d_t *p4d; pud_t *pud; pmd_t *pmd; int rc; BUG_ON(gmap_is_shadow(gmap)); /* Create higher level tables in the gmap page table */ table = gmap->table; if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION1) { table += (gaddr & _REGION1_INDEX) >> _REGION1_SHIFT; if ((*table & _REGION_ENTRY_INVALID) && gmap_alloc_table(gmap, table, _REGION2_ENTRY_EMPTY, gaddr & _REGION1_MASK)) return -ENOMEM; table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); } if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION2) { table += (gaddr & _REGION2_INDEX) >> _REGION2_SHIFT; if ((*table & _REGION_ENTRY_INVALID) && gmap_alloc_table(gmap, table, _REGION3_ENTRY_EMPTY, gaddr & _REGION2_MASK)) return -ENOMEM; table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); } if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION3) { table += (gaddr & _REGION3_INDEX) >> _REGION3_SHIFT; if ((*table & _REGION_ENTRY_INVALID) && gmap_alloc_table(gmap, table, _SEGMENT_ENTRY_EMPTY, gaddr & _REGION3_MASK)) return -ENOMEM; table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); } table += (gaddr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT; /* Walk the parent mm page table */ mm = gmap->mm; pgd = pgd_offset(mm, vmaddr); VM_BUG_ON(pgd_none(*pgd)); p4d = p4d_offset(pgd, vmaddr); VM_BUG_ON(p4d_none(*p4d)); pud = pud_offset(p4d, vmaddr); VM_BUG_ON(pud_none(*pud)); /* large puds cannot yet be handled */ if (pud_large(*pud)) return -EFAULT; pmd = pmd_offset(pud, vmaddr); VM_BUG_ON(pmd_none(*pmd)); /* large pmds cannot yet be handled */ if (pmd_large(*pmd)) return -EFAULT; /* Link gmap segment table entry location to page table. */ rc = radix_tree_preload(GFP_KERNEL); if (rc) return rc; ptl = pmd_lock(mm, pmd); spin_lock(&gmap->guest_table_lock); if (*table == _SEGMENT_ENTRY_EMPTY) { rc = radix_tree_insert(&gmap->host_to_guest, vmaddr >> PMD_SHIFT, table); if (!rc) *table = pmd_val(*pmd); } else rc = 0; spin_unlock(&gmap->guest_table_lock); spin_unlock(ptl); radix_tree_preload_end(); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky43592.95%350.00%
Heiko Carstens194.06%116.67%
Gerald Schaefer132.78%116.67%
Dominik Dingel10.21%116.67%
Total468100.00%6100.00%

/** * gmap_fault - resolve a fault on a guest address * @gmap: pointer to guest mapping meta data structure * @gaddr: guest address * @fault_flags: flags to pass down to handle_mm_fault() * * Returns 0 on success, -ENOMEM for out of memory conditions, and -EFAULT * if the vm address is already mapped to a different guest segment. */
int gmap_fault(struct gmap *gmap, unsigned long gaddr, unsigned int fault_flags) { unsigned long vmaddr; int rc; bool unlocked; down_read(&gmap->mm->mmap_sem); retry: unlocked = false; vmaddr = __gmap_translate(gmap, gaddr); if (IS_ERR_VALUE(vmaddr)) { rc = vmaddr; goto out_up; } if (fixup_user_fault(current, gmap->mm, vmaddr, fault_flags, &unlocked)) { rc = -EFAULT; goto out_up; } /* * In the case that fixup_user_fault unlocked the mmap_sem during * faultin redo __gmap_translate to not race with a map/unmap_segment. */ if (unlocked) goto retry; rc = __gmap_link(gmap, gaddr, vmaddr); out_up: up_read(&gmap->mm->mmap_sem); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky131100.00%1100.00%
Total131100.00%1100.00%

EXPORT_SYMBOL_GPL(gmap_fault); /* * this function is assumed to be called with mmap_sem held */
void __gmap_zap(struct gmap *gmap, unsigned long gaddr) { unsigned long vmaddr; spinlock_t *ptl; pte_t *ptep; /* Find the vm address for the guest address */ vmaddr = (unsigned long) radix_tree_lookup(&gmap->guest_to_host, gaddr >> PMD_SHIFT); if (vmaddr) { vmaddr |= gaddr & ~PMD_MASK; /* Get pointer to the page table entry */ ptep = get_locked_pte(gmap->mm, vmaddr, &ptl); if (likely(ptep)) ptep_zap_unused(gmap->mm, vmaddr, ptep, 0); pte_unmap_unlock(ptep, ptl); } }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky100100.00%1100.00%
Total100100.00%1100.00%

EXPORT_SYMBOL_GPL(__gmap_zap);
void gmap_discard(struct gmap *gmap, unsigned long from, unsigned long to) { unsigned long gaddr, vmaddr, size; struct vm_area_struct *vma; down_read(&gmap->mm->mmap_sem); for (gaddr = from; gaddr < to; gaddr = (gaddr + PMD_SIZE) & PMD_MASK) { /* Find the vm address for the guest address */ vmaddr = (unsigned long) radix_tree_lookup(&gmap->guest_to_host, gaddr >> PMD_SHIFT); if (!vmaddr) continue; vmaddr |= gaddr & ~PMD_MASK; /* Find vma in the parent mm */ vma = find_vma(gmap->mm, vmaddr); size = min(to - gaddr, PMD_SIZE - (gaddr & ~PMD_MASK)); zap_page_range(vma, vmaddr, size); } up_read(&gmap->mm->mmap_sem); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky144100.00%1100.00%
Total144100.00%1100.00%

EXPORT_SYMBOL_GPL(gmap_discard); static LIST_HEAD(gmap_notifier_list); static DEFINE_SPINLOCK(gmap_notifier_lock); /** * gmap_register_pte_notifier - register a pte invalidation callback * @nb: pointer to the gmap notifier block */
void gmap_register_pte_notifier(struct gmap_notifier *nb) { spin_lock(&gmap_notifier_lock); list_add_rcu(&nb->list, &gmap_notifier_list); spin_unlock(&gmap_notifier_lock); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky33100.00%3100.00%
Total33100.00%3100.00%

EXPORT_SYMBOL_GPL(gmap_register_pte_notifier); /** * gmap_unregister_pte_notifier - remove a pte invalidation callback * @nb: pointer to the gmap notifier block */
void gmap_unregister_pte_notifier(struct gmap_notifier *nb) { spin_lock(&gmap_notifier_lock); list_del_rcu(&nb->list); spin_unlock(&gmap_notifier_lock); synchronize_rcu(); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky33100.00%3100.00%
Total33100.00%3100.00%

EXPORT_SYMBOL_GPL(gmap_unregister_pte_notifier); /** * gmap_call_notifier - call all registered invalidation callbacks * @gmap: pointer to guest mapping meta data structure * @start: start virtual address in the guest address space * @end: end virtual address in the guest address space */
static void gmap_call_notifier(struct gmap *gmap, unsigned long start, unsigned long end) { struct gmap_notifier *nb; list_for_each_entry(nb, &gmap_notifier_list, list) nb->notifier_call(gmap, start, end); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky43100.00%2100.00%
Total43100.00%2100.00%

/** * gmap_table_walk - walk the gmap page tables * @gmap: pointer to guest mapping meta data structure * @gaddr: virtual address in the guest address space * @level: page table level to stop at * * Returns a table entry pointer for the given guest address and @level * @level=0 : returns a pointer to a page table table entry (or NULL) * @level=1 : returns a pointer to a segment table entry (or NULL) * @level=2 : returns a pointer to a region-3 table entry (or NULL) * @level=3 : returns a pointer to a region-2 table entry (or NULL) * @level=4 : returns a pointer to a region-1 table entry (or NULL) * * Returns NULL if the gmap page tables could not be walked to the * requested level. * * Note: Can also be called for shadow gmaps. */
static inline unsigned long *gmap_table_walk(struct gmap *gmap, unsigned long gaddr, int level) { unsigned long *table; if ((gmap->asce & _ASCE_TYPE_MASK) + 4 < (level * 4)) return NULL; if (gmap_is_shadow(gmap) && gmap->removed) return NULL; if (gaddr & (-1UL << (31 + ((gmap->asce & _ASCE_TYPE_MASK) >> 2)*11))) return NULL; table = gmap->table; switch (gmap->asce & _ASCE_TYPE_MASK) { case _ASCE_TYPE_REGION1: table += (gaddr & _REGION1_INDEX) >> _REGION1_SHIFT; if (level == 4) break; if (*table & _REGION_ENTRY_INVALID) return NULL; table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); /* Fallthrough */ case _ASCE_TYPE_REGION2: table += (gaddr & _REGION2_INDEX) >> _REGION2_SHIFT; if (level == 3) break; if (*table & _REGION_ENTRY_INVALID) return NULL; table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); /* Fallthrough */ case _ASCE_TYPE_REGION3: table += (gaddr & _REGION3_INDEX) >> _REGION3_SHIFT; if (level == 2) break; if (*table & _REGION_ENTRY_INVALID) return NULL; table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); /* Fallthrough */ case _ASCE_TYPE_SEGMENT: table += (gaddr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT; if (level == 1) break; if (*table & _REGION_ENTRY_INVALID) return NULL; table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN); table += (gaddr & _PAGE_INDEX) >> _PAGE_SHIFT; } return table; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky27993.31%375.00%
Heiko Carstens206.69%125.00%
Total299100.00%4100.00%

/** * gmap_pte_op_walk - walk the gmap page table, get the page table lock * and return the pte pointer * @gmap: pointer to guest mapping meta data structure * @gaddr: virtual address in the guest address space * @ptl: pointer to the spinlock pointer * * Returns a pointer to the locked pte for a guest address, or NULL * * Note: Can also be called for shadow gmaps. */
static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr, spinlock_t **ptl) { unsigned long *table; if (gmap_is_shadow(gmap)) spin_lock(&gmap->guest_table_lock); /* Walk the gmap page table, lock and get pte pointer */ table = gmap_table_walk(gmap, gaddr, 1); /* get segment pointer */ if (!table || *table & _SEGMENT_ENTRY_INVALID) { if (gmap_is_shadow(gmap)) spin_unlock(&gmap->guest_table_lock); return NULL; } if (gmap_is_shadow(gmap)) { *ptl = &gmap->guest_table_lock; return pte_offset_map((pmd_t *) table, gaddr); } return pte_alloc_map_lock(gmap->mm, (pmd_t *) table, gaddr, ptl); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky131100.00%2100.00%
Total131100.00%2100.00%

/** * gmap_pte_op_fixup - force a page in and connect the gmap page table * @gmap: pointer to guest mapping meta data structure * @gaddr: virtual address in the guest address space * @vmaddr: address in the host process address space * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE * * Returns 0 if the caller can retry __gmap_translate (might fail again), * -ENOMEM if out of memory and -EFAULT if anything goes wrong while fixing * up or connecting the gmap page table. */
static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr, int prot) { struct mm_struct *mm = gmap->mm; unsigned int fault_flags; bool unlocked = false; BUG_ON(gmap_is_shadow(gmap)); fault_flags = (prot == PROT_WRITE) ? FAULT_FLAG_WRITE : 0; if (fixup_user_fault(current, mm, vmaddr, fault_flags, &unlocked)) return -EFAULT; if (unlocked) /* lost mmap_sem, caller has to retry __gmap_translate */ return 0; /* Connect the page tables */ return __gmap_link(gmap, gaddr, vmaddr); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky7979.80%266.67%
David Hildenbrand2020.20%133.33%
Total99100.00%3100.00%

/** * gmap_pte_op_end - release the page table lock * @ptl: pointer to the spinlock pointer */
static void gmap_pte_op_end(spinlock_t *ptl) { spin_unlock(ptl); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky15100.00%1100.00%
Total15100.00%1100.00%

/* * gmap_protect_range - remove access rights to memory and set pgste bits * @gmap: pointer to guest mapping meta data structure * @gaddr: virtual address in the guest address space * @len: size of area * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE * @bits: pgste notification bits to set * * Returns 0 if successfully protected, -ENOMEM if out of memory and * -EFAULT if gaddr is invalid (or mapping for shadows is missing). * * Called with sg->mm->mmap_sem in read. * * Note: Can also be called for shadow gmaps. */
static int gmap_protect_range(struct gmap *gmap, unsigned long gaddr, unsigned long len, int prot, unsigned long bits) { unsigned long vmaddr; spinlock_t *ptl; pte_t *ptep; int rc; while (len) { rc = -EAGAIN; ptep = gmap_pte_op_walk(gmap, gaddr, &ptl); if (ptep) { rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot, bits); gmap_pte_op_end(ptl); } if (rc) { vmaddr = __gmap_translate(gmap, gaddr); if (IS_ERR_VALUE(vmaddr)) return vmaddr; rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, prot); if (rc) return rc; continue; } gaddr += PAGE_SIZE; len -= PAGE_SIZE; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky14798.66%375.00%
David Hildenbrand21.34%125.00%
Total149100.00%4100.00%

/** * gmap_mprotect_notify - change access rights for a range of ptes and * call the notifier if any pte changes again * @gmap: pointer to guest mapping meta data structure * @gaddr: virtual address in the guest address space * @len: size of area * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE * * Returns 0 if for each page in the given range a gmap mapping exists, * the new access rights could be set and the notifier could be armed. * If the gmap mapping is missing for one or more pages -EFAULT is * returned. If no memory could be allocated -ENOMEM is returned. * This function establishes missing page table entries. */
int gmap_mprotect_notify(struct gmap *gmap, unsigned long gaddr, unsigned long len, int prot) { int rc; if ((gaddr & ~PAGE_MASK) || (len & ~PAGE_MASK) || gmap_is_shadow(gmap)) return -EINVAL; if (!MACHINE_HAS_ESOP && prot == PROT_READ) return -EINVAL; down_read(&gmap->mm->mmap_sem); rc = gmap_protect_range(gmap, gaddr, len, prot, PGSTE_IN_BIT); up_read(&gmap->mm->mmap_sem); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky100100.00%1100.00%
Total100100.00%1100.00%

EXPORT_SYMBOL_GPL(gmap_mprotect_notify); /** * gmap_read_table - get an unsigned long value from a guest page table using * absolute addressing, without marking the page referenced. * @gmap: pointer to guest mapping meta data structure * @gaddr: virtual address in the guest address space * @val: pointer to the unsigned long value to return * * Returns 0 if the value was read, -ENOMEM if out of memory and -EFAULT * if reading using the virtual address failed. * * Called with gmap->mm->mmap_sem in read. */
int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val) { unsigned long address, vmaddr; spinlock_t *ptl; pte_t *ptep, pte; int rc; while (1) { rc = -EAGAIN; ptep = gmap_pte_op_walk(gmap, gaddr, &ptl); if (ptep) { pte = *ptep; if (pte_present(pte) && (pte_val(pte) & _PAGE_READ)) { address = pte_val(pte) & PAGE_MASK; address += gaddr & ~PAGE_MASK; *val = *(unsigned long *) address; pte_val(*ptep) |= _PAGE_YOUNG; /* Do *NOT* clear the _PAGE_INVALID bit! */ rc = 0; } gmap_pte_op_end(ptl); } if (!rc) break; vmaddr = __gmap_translate(gmap, gaddr); if (IS_ERR_VALUE(vmaddr)) { rc = vmaddr; break; } rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, PROT_READ); if (rc) break; } return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky18398.92%150.00%
David Hildenbrand21.08%150.00%
Total185100.00%2100.00%

EXPORT_SYMBOL_GPL(gmap_read_table); /** * gmap_insert_rmap - add a rmap to the host_to_rmap radix tree * @sg: pointer to the shadow guest address space structure * @vmaddr: vm address associated with the rmap * @rmap: pointer to the rmap structure * * Called with the sg->guest_table_lock */
static inline void gmap_insert_rmap(struct gmap *sg, unsigned long vmaddr, struct gmap_rmap *rmap) { void __rcu **slot; BUG_ON(!gmap_is_shadow(sg)); slot = radix_tree_lookup_slot(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT); if (slot) { rmap->next = radix_tree_deref_slot_protected(slot, &sg->guest_table_lock); radix_tree_replace_slot(&sg->host_to_rmap, slot, rmap); } else { rmap->next = NULL; radix_tree_insert(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT, rmap); } }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky9994.29%133.33%
Johannes Weiner54.76%133.33%
Heiko Carstens10.95%133.33%
Total105100.00%3100.00%

/** * gmap_protect_rmap - modify access rights to memory and create an rmap * @sg: pointer to the shadow guest address space structure * @raddr: rmap address in the shadow gmap * @paddr: address in the parent guest address space * @len: length of the memory area to protect * @prot: indicates access rights: none, read-only or read-write * * Returns 0 if successfully protected and the rmap was created, -ENOMEM * if out of memory and -EFAULT if paddr is invalid. */
static int gmap_protect_rmap(struct gmap *sg, unsigned long raddr, unsigned long paddr, unsigned long len, int prot) { struct gmap *parent; struct gmap_rmap *rmap; unsigned long vmaddr; spinlock_t *ptl; pte_t *ptep; int rc; BUG_ON(!gmap_is_shadow(sg)); parent = sg->parent; while (len) { vmaddr = __gmap_translate(parent, paddr); if (IS_ERR_VALUE(vmaddr)) return vmaddr; rmap = kzalloc(sizeof(*rmap), GFP_KERNEL); if (!rmap) return -ENOMEM; rmap->raddr = raddr; rc = radix_tree_preload(GFP_KERNEL); if (rc) { kfree(rmap); return rc; } rc = -EAGAIN; ptep = gmap_pte_op_walk(parent, paddr, &ptl); if (ptep) { spin_lock(&sg->guest_table_lock); rc = ptep_force_prot(parent->mm, paddr, ptep, prot, PGSTE_VSIE_BIT); if (!rc) gmap_insert_rmap(sg, vmaddr, rmap); spin_unlock(&sg->guest_table_lock); gmap_pte_op_end(ptl); } radix_tree_preload_end(); if (rc) { kfree(rmap); rc = gmap_pte_op_fixup(parent, paddr, vmaddr, prot); if (rc) return rc; continue; } paddr += PAGE_SIZE; len -= PAGE_SIZE; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky25999.23%150.00%
David Hildenbrand20.77%150.00%
Total261100.00%2100.00%

#define _SHADOW_RMAP_MASK 0x7 #define _SHADOW_RMAP_REGION1 0x5 #define _SHADOW_RMAP_REGION2 0x4 #define _SHADOW_RMAP_REGION3 0x3 #define _SHADOW_RMAP_SEGMENT 0x2 #define _SHADOW_RMAP_PGTABLE 0x1 /** * gmap_idte_one - invalidate a single region or segment table entry * @asce: region or segment table *origin* + table-type bits * @vaddr: virtual address to identify the table entry to flush * * The invalid bit of a single region or segment table entry is set * and the associated TLB entries depending on the entry are flushed. * The table-type of the @asce identifies the portion of the @vaddr * that is used as the invalidation index. */
static inline void gmap_idte_one(unsigned long asce, unsigned long vaddr) { asm volatile( " .insn rrf,0xb98e0000,%0,%1,0,0" : : "a" (asce), "a" (vaddr) : "cc", "memory"); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky18100.00%1100.00%
Total18100.00%1100.00%

/** * gmap_unshadow_page - remove a page from a shadow page table * @sg: pointer to the shadow guest address space structure * @raddr: rmap address in the shadow guest address space * * Called with the sg->guest_table_lock */
static void gmap_unshadow_page(struct gmap *sg, unsigned long raddr) { unsigned long *table; BUG_ON(!gmap_is_shadow(sg)); table = gmap_table_walk(sg, raddr, 0); /* get page table pointer */ if (!table || *table & _PAGE_INVALID) return; gmap_call_notifier(sg, raddr, raddr + _PAGE_SIZE - 1); ptep_unshadow_pte(sg->mm, raddr, (pte_t *) table); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky7998.75%150.00%
Heiko Carstens11.25%150.00%
Total80100.00%2100.00%

/** * __gmap_unshadow_pgt - remove all entries from a shadow page table * @sg: pointer to the shadow guest address space structure * @raddr: rmap address in the shadow guest address space * @pgt: pointer to the start of a shadow page table * * Called with the sg->guest_table_lock */
static void __gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr, unsigned long *pgt) { int i; BUG_ON(!gmap_is_shadow(sg)); for (i = 0; i < _PAGE_ENTRIES; i++, raddr += _PAGE_SIZE) pgt[i] = _PAGE_INVALID; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky5496.43%150.00%
Heiko Carstens23.57%150.00%
Total56100.00%2100.00%

/** * gmap_unshadow_pgt - remove a shadow page table from a segment entry * @sg: pointer to the shadow guest address space structure * @raddr: address in the shadow guest address space * * Called with the sg->guest_table_lock */
static void gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr) { unsigned long sto, *ste, *pgt; struct page *page; BUG_ON(!gmap_is_shadow(sg)); ste = gmap_table_walk(sg, raddr, 1); /* get segment pointer */ if (!ste || !(*ste & _SEGMENT_ENTRY_ORIGIN)) return; gmap_call_notifier(sg, raddr, raddr + _SEGMENT_SIZE - 1); sto = (unsigned long) (ste - ((raddr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT)); gmap_idte_one(sto | _ASCE_TYPE_SEGMENT, raddr); pgt = (unsigned long *)(*ste & _SEGMENT_ENTRY_ORIGIN); *ste = _SEGMENT_ENTRY_EMPTY; __gmap_unshadow_pgt(sg, raddr, pgt); /* Free page table */ page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT); list_del(&page->lru); page_table_free_pgste(page); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky15294.41%133.33%
Heiko Carstens53.11%133.33%
David Hildenbrand42.48%133.33%
Total161100.00%3100.00%

/** * __gmap_unshadow_sgt - remove all entries from a shadow segment table * @sg: pointer to the shadow guest address space structure * @raddr: rmap address in the shadow guest address space * @sgt: pointer to the start of a shadow segment table * * Called with the sg->guest_table_lock */
static void __gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr, unsigned long *sgt) { unsigned long asce, *pgt; struct page *page; int i; BUG_ON(!gmap_is_shadow(sg)); asce = (unsigned long) sgt | _ASCE_TYPE_SEGMENT; for (i = 0; i < _CRST_ENTRIES; i++, raddr += _SEGMENT_SIZE) { if (!(sgt[i] & _SEGMENT_ENTRY_ORIGIN)) continue; pgt = (unsigned long *)(sgt[i] & _REGION_ENTRY_ORIGIN); sgt[i] = _SEGMENT_ENTRY_EMPTY; __gmap_unshadow_pgt(sg, raddr, pgt); /* Free page table */ page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT); list_del(&page->lru); page_table_free_pgste(page); } }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky13895.83%133.33%
David Hildenbrand42.78%133.33%
Heiko Carstens21.39%133.33%
Total144100.00%3100.00%

/** * gmap_unshadow_sgt - remove a shadow segment table from a region-3 entry * @sg: pointer to the shadow guest address space structure * @raddr: rmap address in the shadow guest address space * * Called with the shadow->guest_table_lock */
static void gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr) { unsigned long r3o, *r3e, *sgt; struct page *page; BUG_ON(!gmap_is_shadow(sg)); r3e = gmap_table_walk(sg, raddr, 2); /* get region-3 pointer */ if (!r3e || !(*r3e & _REGION_ENTRY_ORIGIN)) return; gmap_call_notifier(sg, raddr, raddr + _REGION3_SIZE - 1); r3o = (unsigned long) (r3e - ((raddr & _REGION3_INDEX) >> _REGION3_SHIFT)); gmap_idte_one(r3o | _ASCE_TYPE_REGION3, raddr); sgt = (unsigned long *)(*r3e & _REGION_ENTRY_ORIGIN); *r3e = _REGION3_ENTRY_EMPTY; __gmap_unshadow_sgt(sg, raddr, sgt); /* Free segment table */ page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT); list_del(&page->lru); __free_pages(page, CRST_ALLOC_ORDER); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky15393.87%133.33%
Heiko Carstens63.68%133.33%
David Hildenbrand42.45%133.33%
Total163100.00%3100.00%

/** * __gmap_unshadow_r3t - remove all entries from a shadow region-3 table * @sg: pointer to the shadow guest address space structure * @raddr: address in the shadow guest address space * @r3t: pointer to the start of a shadow region-3 table * * Called with the sg->guest_table_lock */
static void __gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr, unsigned long *r3t) { unsigned long asce, *sgt; struct page *page; int i; BUG_ON(!gmap_is_shadow(sg)); asce = (unsigned long) r3t | _ASCE_TYPE_REGION3; for (i = 0; i < _CRST_ENTRIES; i++, raddr += _REGION3_SIZE) { if (!(r3t[i] & _REGION_ENTRY_ORIGIN)) continue; sgt = (unsigned long *)(r3t[i] & _REGION_ENTRY_ORIGIN); r3t[i] = _REGION3_ENTRY_EMPTY; __gmap_unshadow_sgt(sg, raddr, sgt); /* Free segment table */ page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT); list_del(&page->lru); __free_pages(page, CRST_ALLOC_ORDER); } }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky13995.21%133.33%
David Hildenbrand42.74%133.33%
Heiko Carstens32.05%133.33%
Total146100.00%3100.00%

/** * gmap_unshadow_r3t - remove a shadow region-3 table from a region-2 entry * @sg: pointer to the shadow guest address space structure * @raddr: rmap address in the shadow guest address space * * Called with the sg->guest_table_lock */
static void gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr) { unsigned long r2o, *r2e, *r3t; struct page *page; BUG_ON(!gmap_is_shadow(sg)); r2e = gmap_table_walk(sg, raddr, 3); /* get region-2 pointer */ if (!r2e || !(*r2e & _REGION_ENTRY_ORIGIN)) return; gmap_call_notifier(sg, raddr, raddr + _REGION2_SIZE - 1); r2o = (unsigned long) (r2e - ((raddr & _REGION2_INDEX) >> _REGION2_SHIFT)); gmap_idte_one(r2o | _ASCE_TYPE_REGION2, raddr); r3t = (unsigned long *)(*r2e & _REGION_ENTRY_ORIGIN); *r2e = _REGION2_ENTRY_EMPTY; __gmap_unshadow_r3t(sg, raddr, r3t); /* Free region 3 table */ page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT); list_del(&page->lru); __free_pages(page, CRST_ALLOC_ORDER); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky15393.87%133.33%
Heiko Carstens63.68%133.33%
David Hildenbrand42.45%133.33%
Total163100.00%3100.00%

/** * __gmap_unshadow_r2t - remove all entries from a shadow region-2 table * @sg: pointer to the shadow guest address space structure * @raddr: rmap address in the shadow guest address space * @r2t: pointer to the start of a shadow region-2 table * * Called with the sg->guest_table_lock */
static void __gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr, unsigned long *r2t) { unsigned long asce, *r3t; struct page *page; int i; BUG_ON(!gmap_is_shadow(sg)); asce = (unsigned long) r2t | _ASCE_TYPE_REGION2; for (i = 0; i < _CRST_ENTRIES; i++, raddr += _REGION2_SIZE) { if (!(r2t[i] & _REGION_ENTRY_ORIGIN)) continue; r3t = (unsigned long *)(r2t[i] & _REGION_ENTRY_ORIGIN); r2t[i] = _REGION2_ENTRY_EMPTY; __gmap_unshadow_r3t(sg, raddr, r3t); /* Free region 3 table */ page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT); list_del(&page->lru); __free_pages(page, CRST_ALLOC_ORDER); } }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky13995.21%133.33%
David Hildenbrand42.74%133.33%
Heiko Carstens32.05%133.33%
Total146100.00%3100.00%

/** * gmap_unshadow_r2t - remove a shadow region-2 table from a region-1 entry * @sg: pointer to the shadow guest address space structure * @raddr: rmap address in the shadow guest address space * * Called with the sg->guest_table_lock */
static void gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr) { unsigned long r1o, *r1e, *r2t; struct page *page; BUG_ON(!gmap_is_shadow(sg)); r1e = gmap_table_walk(sg, raddr, 4); /* get region-1 pointer */ if (!r1e || !(*r1e & _REGION_ENTRY_ORIGIN)) return; gmap_call_notifier(sg, raddr, raddr + _REGION1_SIZE - 1); r1o = (unsigned long) (r1e - ((raddr & _REGION1_INDEX) >> _REGION1_SHIFT)); gmap_idte_one(r1o | _ASCE_TYPE_REGION1, raddr); r2t = (unsigned long *)(*r1e & _REGION_ENTRY_ORIGIN); *r1e = _REGION1_ENTRY_EMPTY; __gmap_unshadow_r2t(sg, raddr, r2t); /* Free region 2 table */ page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT); list_del(&page->lru); __free_pages(page, CRST_ALLOC_ORDER); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky15393.87%133.33%
Heiko Carstens63.68%133.33%
David Hildenbrand42.45%133.33%
Total163100.00%3100.00%

/** * __gmap_unshadow_r1t - remove all entries from a shadow region-1 table * @sg: pointer to the shadow guest address space structure * @raddr: rmap address in the shadow guest address space * @r1t: pointer to the start of a shadow region-1 table * * Called with the shadow->guest_table_lock */
static void __gmap_unshadow_r1t(struct gmap *sg, unsigned long raddr, unsigned long *r1t) { unsigned long asce, *r2t; struct page *page; int i; BUG_ON(!gmap_is_shadow(sg)); asce = (unsigned long) r1t | _ASCE_TYPE_REGION1; for (i = 0; i < _CRST_ENTRIES; i++, raddr += _REGION1_SIZE) { if (!(r1t[i] & _REGION_ENTRY_ORIGIN)) continue; r2t = (unsigned long *)(r1t[i] & _REGION_ENTRY_ORIGIN); __gmap_unshadow_r2t(sg, raddr, r2t); /* Clear entry and flush translation r1t -> r2t */ gmap_idte_one(asce, raddr); r1t[i] = _REGION1_ENTRY_EMPTY; /* Free region 2 table */ page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT); list_del(&page->lru); __free_pages(page, CRST_ALLOC_ORDER); } }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky14795.45%133.33%
David Hildenbrand42.60%133.33%
Heiko Carstens31.95%133.33%
Total154100.00%3100.00%

/** * gmap_unshadow - remove a shadow page table completely * @sg: pointer to the shadow guest address space structure * * Called with sg->guest_table_lock */
static void gmap_unshadow(struct gmap *sg) { unsigned long *table; BUG_ON(!gmap_is_shadow(sg)); if (sg->removed) return; sg->removed = 1; gmap_call_notifier(sg, 0, -1UL); gmap_flush_tlb(sg); table = (unsigned long *)(sg->asce & _ASCE_ORIGIN); switch (sg->asce & _ASCE_TYPE_MASK) { case _ASCE_TYPE_REGION1: __gmap_unshadow_r1t(sg, 0, table); break; case _ASCE_TYPE_REGION2: __gmap_unshadow_r2t(sg, 0, table); break; case _ASCE_TYPE_REGION3: __gmap_unshadow_r3t(sg, 0, table); break; case _ASCE_TYPE_SEGMENT: __gmap_unshadow_sgt(sg, 0, table); break; } }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky12596.15%150.00%
David Hildenbrand53.85%150.00%
Total130100.00%2100.00%

/** * gmap_find_shadow - find a specific asce in the list of shadow tables * @parent: pointer to the parent gmap * @asce: ASCE for which the shadow table is created * @edat_level: edat level to be used for the shadow translation * * Returns the pointer to a gmap if a shadow table with the given asce is * already available, ERR_PTR(-EAGAIN) if another one is just being created, * otherwise NULL */
static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce, int edat_level) { struct gmap *sg; list_for_each_entry(sg, &parent->children, list) { if (sg->orig_asce != asce || sg->edat_level != edat_level || sg->removed) continue; if (!sg->initialized) return ERR_PTR(-EAGAIN); atomic_inc(&sg->ref_count); return sg; } return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky5971.95%133.33%
David Hildenbrand2328.05%266.67%
Total82100.00%3100.00%

/** * gmap_shadow_valid - check if a shadow guest address space matches the * given properties and is still valid * @sg: pointer to the shadow guest address space structure * @asce: ASCE for which the shadow table is requested * @edat_level: edat level to be used for the shadow translation * * Returns 1 if the gmap shadow is still valid and matches the given * properties, the caller can continue using it. Returns 0 otherwise, the * caller has to request a new shadow gmap in this case. * */
int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level) { if (sg->removed) return 0; return sg->orig_asce == asce && sg->edat_level == edat_level; }

Contributors

PersonTokensPropCommitsCommitProp
David Hildenbrand39100.00%1100.00%
Total39100.00%1100.00%

EXPORT_SYMBOL_GPL(gmap_shadow_valid); /** * gmap_shadow - create/find a shadow guest address space * @parent: pointer to the parent gmap * @asce: ASCE for which the shadow table is created * @edat_level: edat level to be used for the shadow translation * * The pages of the top level page table referred by the asce parameter * will be set to read-only and marked in the PGSTEs of the kvm process. * The shadow table will be removed automatically on any change to the * PTE mapping for the source table. * * Returns a guest address space structure, ERR_PTR(-ENOMEM) if out of memory, * ERR_PTR(-EAGAIN) if the caller has to retry and ERR_PTR(-EFAULT) if the * parent gmap table could not be protected. */
struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce, int edat_level) { struct gmap *sg, *new; unsigned long limit; int rc; BUG_ON(gmap_is_shadow(parent)); spin_lock(&parent->shadow_lock); sg = gmap_find_shadow(parent, asce, edat_level); spin_unlock(&parent->shadow_lock); if (sg) return sg; /* Create a new shadow gmap */ limit = -1UL >> (33 - (((asce & _ASCE_TYPE_MASK) >> 2) * 11)); if (asce & _ASCE_REAL_SPACE) limit = -1UL; new = gmap_alloc(limit); if (!new) return ERR_PTR(-ENOMEM); new->mm = parent->mm; new->parent = gmap_get(parent); new->orig_asce = asce; new->edat_level = edat_level; new->initialized = false; spin_lock(&parent->shadow_lock); /* Recheck if another CPU created the same shadow */ sg = gmap_find_shadow(parent, asce, edat_level); if (sg) { spin_unlock(&parent->shadow_lock); gmap_free(new); return sg; } if (asce & _ASCE_REAL_SPACE) { /* only allow one real-space gmap shadow */ list_for_each_entry(sg, &parent->children, list) { if (sg->orig_asce & _ASCE_REAL_SPACE) { spin_lock(&sg->guest_table_lock); gmap_unshadow(sg); spin_unlock(&sg->guest_table_lock); list_del(&sg->list); gmap_put(sg); break; } } } atomic_set(&new->ref_count, 2); list_add(&new->list, &parent->children); if (asce & _ASCE_REAL_SPACE) { /* nothing to protect, return right away */ new->initialized = true; spin_unlock(&parent->shadow_lock); return new; } spin_unlock(&parent->shadow_lock); /* protect after insertion, so it will get properly invalidated */ down_read(&parent->mm->mmap_sem); rc = gmap_protect_range(parent, asce & _ASCE_ORIGIN, ((asce & _ASCE_TABLE_LENGTH) + 1) * PAGE_SIZE, PROT_READ, PGSTE_VSIE_BIT); up_read(&parent->mm->mmap_sem); spin_lock(&parent->shadow_lock); new->initialized = true; if (rc) { list_del(&new->list); gmap_free(new); new = ERR_PTR(rc); } spin_unlock(&parent->shadow_lock); return new; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky21550.35%116.67%
David Hildenbrand21149.41%466.67%
Heiko Carstens10.23%116.67%
Total427100.00%6100.00%

EXPORT_SYMBOL_GPL(gmap_shadow); /** * gmap_shadow_r2t - create an empty shadow region 2 table * @sg: pointer to the shadow guest address space structure * @saddr: faulting address in the shadow gmap * @r2t: parent gmap address of the region 2 table to get shadowed * @fake: r2t references contiguous guest memory block, not a r2t * * The r2t parameter specifies the address of the source table. The * four pages of the source table are made read-only in the parent gmap * address space. A write to the source table area @r2t will automatically * remove the shadow r2 table and all of its decendents. * * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the * shadow table structure is incomplete, -ENOMEM if out of memory and * -EFAULT if an address in the parent gmap could not be resolved. * * Called with sg->mm->mmap_sem in read. */
int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t, int fake) { unsigned long raddr, origin, offset, len; unsigned long *s_r2t, *table; struct page *page; int rc; BUG_ON(!gmap_is_shadow(sg)); /* Allocate a shadow region second table */ page = alloc_pages(GFP_KERNEL, CRST_ALLOC_ORDER); if (!page) return -ENOMEM; page->index = r2t & _REGION_ENTRY_ORIGIN; if (fake) page->index |= GMAP_SHADOW_FAKE_TABLE; s_r2t = (unsigned long *) page_to_phys(page); /* Install shadow region second table */ spin_lock(&sg->guest_table_lock); table = gmap_table_walk(sg, saddr, 4); /* get region-1 pointer */ if (!table) { rc = -EAGAIN; /* Race with unshadow */ goto out_free; } if (!(*table & _REGION_ENTRY_INVALID)) { rc = 0; /* Already established */ goto out_free; } else if (*table & _REGION_ENTRY_ORIGIN) { rc = -EAGAIN; /* Race with shadow */ goto out_free; } crst_table_init(s_r2t, _REGION2_ENTRY_EMPTY); /* mark as invalid as long as the parent table is not protected */ *table = (unsigned long) s_r2t | _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INVALID; if (sg->edat_level >= 1) *table |= (r2t & _REGION_ENTRY_PROTECT); list_add(&page->lru, &sg->crst_list); if (fake) { /* nothing to protect for fake tables */ *table &= ~_REGION_ENTRY_INVALID; spin_unlock(&sg->guest_table_lock); return 0; } spin_unlock(&sg->guest_table_lock); /* Make r2t read-only in parent gmap page table */ raddr = (saddr & _REGION1_MASK) | _SHADOW_RMAP_REGION1; origin = r2t & _REGION_ENTRY_ORIGIN; offset = ((r2t & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE; len = ((r2t & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset; rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ); spin_lock(&sg->guest_table_lock); if (!rc) { table = gmap_table_walk(sg, saddr, 4); if (!table || (*table & _REGION_ENTRY_ORIGIN) != (unsigned long) s_r2t) rc = -EAGAIN; /* Race with unshadow */ else *table &= ~_REGION_ENTRY_INVALID; } else { gmap_unshadow_r2t(sg, raddr); } spin_unlock(&sg->guest_table_lock); return rc; out_free: spin_unlock(&sg->guest_table_lock); __free_pages(page, CRST_ALLOC_ORDER); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky29669.16%120.00%
David Hildenbrand12729.67%360.00%
Heiko Carstens51.17%120.00%
Total428100.00%5100.00%

EXPORT_SYMBOL_GPL(gmap_shadow_r2t); /** * gmap_shadow_r3t - create a shadow region 3 table * @sg: pointer to the shadow guest address space structure * @saddr: faulting address in the shadow gmap * @r3t: parent gmap address of the region 3 table to get shadowed * @fake: r3t references contiguous guest memory block, not a r3t * * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the * shadow table structure is incomplete, -ENOMEM if out of memory and * -EFAULT if an address in the parent gmap could not be resolved. * * Called with sg->mm->mmap_sem in read. */
int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t, int fake) { unsigned long raddr, origin, offset, len; unsigned long *s_r3t, *table; struct page *page; int rc; BUG_ON(!gmap_is_shadow(sg)); /* Allocate a shadow region second table */ page = alloc_pages(GFP_KERNEL, CRST_ALLOC_ORDER); if (!page) return -ENOMEM; page->index = r3t & _REGION_ENTRY_ORIGIN; if (fake) page->index |= GMAP_SHADOW_FAKE_TABLE; s_r3t = (unsigned long *) page_to_phys(page); /* Install shadow region second table */ spin_lock(&sg->guest_table_lock); table = gmap_table_walk(sg, saddr, 3); /* get region-2 pointer */ if (!table) { rc = -EAGAIN; /* Race with unshadow */ goto out_free; } if (!(*table & _REGION_ENTRY_INVALID)) { rc = 0; /* Already established */ goto out_free; } else if (*table & _REGION_ENTRY_ORIGIN) { rc = -EAGAIN; /* Race with shadow */ } crst_table_init(s_r3t, _REGION3_ENTRY_EMPTY); /* mark as invalid as long as the parent table is not protected */ *table = (unsigned long) s_r3t | _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INVALID; if (sg->edat_level >= 1) *table |= (r3t & _REGION_ENTRY_PROTECT); list_add(&page->lru, &sg->crst_list); if (fake) { /* nothing to protect for fake tables */ *table &= ~_REGION_ENTRY_INVALID; spin_unlock(&sg->guest_table_lock); return 0; } spin_unlock(&sg->guest_table_lock); /* Make r3t read-only in parent gmap page table */ raddr = (saddr & _REGION2_MASK) | _SHADOW_RMAP_REGION2; origin = r3t & _REGION_ENTRY_ORIGIN; offset = ((r3t & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE; len = ((r3t & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset; rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ); spin_lock(&sg->guest_table_lock); if (!rc) { table = gmap_table_walk(sg, saddr, 3); if (!table || (*table & _REGION_ENTRY_ORIGIN) != (unsigned long) s_r3t) rc = -EAGAIN; /* Race with unshadow */ else *table &= ~_REGION_ENTRY_INVALID; } else { gmap_unshadow_r3t(sg, raddr); } spin_unlock(&sg->guest_table_lock); return rc; out_free: spin_unlock(&sg->guest_table_lock); __free_pages(page, CRST_ALLOC_ORDER); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky29669.65%120.00%
David Hildenbrand12429.18%360.00%
Heiko Carstens51.18%120.00%
Total425100.00%5100.00%

EXPORT_SYMBOL_GPL(gmap_shadow_r3t); /** * gmap_shadow_sgt - create a shadow segment table * @sg: pointer to the shadow guest address space structure * @saddr: faulting address in the shadow gmap * @sgt: parent gmap address of the segment table to get shadowed * @fake: sgt references contiguous guest memory block, not a sgt * * Returns: 0 if successfully shadowed or already shadowed, -EAGAIN if the * shadow table structure is incomplete, -ENOMEM if out of memory and * -EFAULT if an address in the parent gmap could not be resolved. * * Called with sg->mm->mmap_sem in read. */
int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt, int fake) { unsigned long raddr, origin, offset, len; unsigned long *s_sgt, *table; struct page *page; int rc; BUG_ON(!gmap_is_shadow(sg) || (sgt & _REGION3_ENTRY_LARGE)); /* Allocate a shadow segment table */ page = alloc_pages(GFP_KERNEL, CRST_ALLOC_ORDER); if (!page) return -ENOMEM; page->index = sgt & _REGION_ENTRY_ORIGIN; if (fake) page->index |= GMAP_SHADOW_FAKE_TABLE; s_sgt = (unsigned long *) page_to_phys(page); /* Install shadow region second table */ spin_lock(&sg->guest_table_lock); table = gmap_table_walk(sg, saddr, 2); /* get region-3 pointer */ if (!table) { rc = -EAGAIN; /* Race with unshadow */ goto out_free; } if (!(*table & _REGION_ENTRY_INVALID)) { rc = 0; /* Already established */ goto out_free; } else if (*table & _REGION_ENTRY_ORIGIN) { rc = -EAGAIN; /* Race with shadow */ goto out_free; } crst_table_init(s_sgt, _SEGMENT_ENTRY_EMPTY); /* mark as invalid as long as the parent table is not protected */ *table = (unsigned long) s_sgt | _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INVALID; if (sg->edat_level >= 1) *table |= sgt & _REGION_ENTRY_PROTECT; list_add(&page->lru, &sg->crst_list); if (fake) { /* nothing to protect for fake tables */ *table &= ~_REGION_ENTRY_INVALID; spin_unlock(&sg->guest_table_lock); return 0; } spin_unlock(&sg->guest_table_lock); /* Make sgt read-only in parent gmap page table */ raddr = (saddr & _REGION3_MASK) | _SHADOW_RMAP_REGION3; origin = sgt & _REGION_ENTRY_ORIGIN; offset = ((sgt & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE; len = ((sgt & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset; rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ); spin_lock(&sg->guest_table_lock); if (!rc) { table = gmap_table_walk(sg, saddr, 2); if (!table || (*table & _REGION_ENTRY_ORIGIN) != (unsigned long) s_sgt) rc = -EAGAIN; /* Race with unshadow */ else *table &= ~_REGION_ENTRY_INVALID; } else { gmap_unshadow_sgt(sg, raddr); } spin_unlock(&sg->guest_table_lock); return rc; out_free: spin_unlock(&sg->guest_table_lock); __free_pages(page, CRST_ALLOC_ORDER); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky29668.52%120.00%
David Hildenbrand13130.32%360.00%
Heiko Carstens51.16%120.00%
Total432100.00%5100.00%

EXPORT_SYMBOL_GPL(gmap_shadow_sgt); /** * gmap_shadow_lookup_pgtable - find a shadow page table * @sg: pointer to the shadow guest address space structure * @saddr: the address in the shadow aguest address space * @pgt: parent gmap address of the page table to get shadowed * @dat_protection: if the pgtable is marked as protected by dat * @fake: pgt references contiguous guest memory block, not a pgtable * * Returns 0 if the shadow page table was found and -EAGAIN if the page * table was not found. * * Called with sg->mm->mmap_sem in read. */
int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr, unsigned long *pgt, int *dat_protection, int *fake) { unsigned long *table; struct page *page; int rc; BUG_ON(!gmap_is_shadow(sg)); spin_lock(&sg->guest_table_lock); table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */ if (table && !(*table & _SEGMENT_ENTRY_INVALID)) { /* Shadow page tables are full pages (pte+pgste) */ page = pfn_to_page(*table >> PAGE_SHIFT); *pgt = page->index & ~GMAP_SHADOW_FAKE_TABLE; *dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT); *fake = !!(page->index & GMAP_SHADOW_FAKE_TABLE); rc = 0; } else { rc = -EAGAIN; } spin_unlock(&sg->guest_table_lock); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky13286.84%150.00%
David Hildenbrand2013.16%150.00%
Total152100.00%2100.00%

EXPORT_SYMBOL_GPL(gmap_shadow_pgt_lookup); /** * gmap_shadow_pgt - instantiate a shadow page table * @sg: pointer to the shadow guest address space structure * @saddr: faulting address in the shadow gmap * @pgt: parent gmap address of the page table to get shadowed * @fake: pgt references contiguous guest memory block, not a pgtable * * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the * shadow table structure is incomplete, -ENOMEM if out of memory, * -EFAULT if an address in the parent gmap could not be resolved and * * Called with gmap->mm->mmap_sem in read */
int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt, int fake) { unsigned long raddr, origin; unsigned long *s_pgt, *table; struct page *page; int rc; BUG_ON(!gmap_is_shadow(sg) || (pgt & _SEGMENT_ENTRY_LARGE)); /* Allocate a shadow page table */ page = page_table_alloc_pgste(sg->mm); if (!page) return -ENOMEM; page->index = pgt & _SEGMENT_ENTRY_ORIGIN; if (fake) page->index |= GMAP_SHADOW_FAKE_TABLE; s_pgt = (unsigned long *) page_to_phys(page); /* Install shadow page table */ spin_lock(&sg->guest_table_lock); table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */ if (!table) { rc = -EAGAIN; /* Race with unshadow */ goto out_free; } if (!(*table & _SEGMENT_ENTRY_INVALID)) { rc = 0; /* Already established */ goto out_free; } else if (*table & _SEGMENT_ENTRY_ORIGIN) { rc = -EAGAIN; /* Race with shadow */ goto out_free; } /* mark as invalid as long as the parent table is not protected */ *table = (unsigned long) s_pgt | _SEGMENT_ENTRY | (pgt & _SEGMENT_ENTRY_PROTECT) | _SEGMENT_ENTRY_INVALID; list_add(&page->lru, &sg->pt_list); if (fake) { /* nothing to protect for fake tables */ *table &= ~_SEGMENT_ENTRY_INVALID; spin_unlock(&sg->guest_table_lock); return 0; } spin_unlock(&sg->guest_table_lock); /* Make pgt read-only in parent gmap page table (not the pgste) */ raddr = (saddr & _SEGMENT_MASK) | _SHADOW_RMAP_SEGMENT; origin = pgt & _SEGMENT_ENTRY_ORIGIN & PAGE_MASK; rc = gmap_protect_rmap(sg, raddr, origin, PAGE_SIZE, PROT_READ); spin_lock(&sg->guest_table_lock); if (!rc) { table = gmap_table_walk(sg, saddr, 1); if (!table || (*table & _SEGMENT_ENTRY_ORIGIN) != (unsigned long) s_pgt) rc = -EAGAIN; /* Race with unshadow */ else *table &= ~_SEGMENT_ENTRY_INVALID; } else { gmap_unshadow_pgt(sg, raddr); } spin_unlock(&sg->guest_table_lock); return rc; out_free: spin_unlock(&sg->guest_table_lock); page_table_free_pgste(page); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky26169.05%125.00%
David Hildenbrand11630.69%250.00%
Heiko Carstens10.26%125.00%
Total378100.00%4100.00%

EXPORT_SYMBOL_GPL(gmap_shadow_pgt); /** * gmap_shadow_page - create a shadow page mapping * @sg: pointer to the shadow guest address space structure * @saddr: faulting address in the shadow gmap * @pte: pte in parent gmap address space to get shadowed * * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the * shadow table structure is incomplete, -ENOMEM if out of memory and * -EFAULT if an address in the parent gmap could not be resolved. * * Called with sg->mm->mmap_sem in read. */
int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte) { struct gmap *parent; struct gmap_rmap *rmap; unsigned long vmaddr, paddr; spinlock_t *ptl; pte_t *sptep, *tptep; int prot; int rc; BUG_ON(!gmap_is_shadow(sg)); parent = sg->parent; prot = (pte_val(pte) & _PAGE_PROTECT) ? PROT_READ : PROT_WRITE; rmap = kzalloc(sizeof(*rmap), GFP_KERNEL); if (!rmap) return -ENOMEM; rmap->raddr = (saddr & PAGE_MASK) | _SHADOW_RMAP_PGTABLE; while (1) { paddr = pte_val(pte) & PAGE_MASK; vmaddr = __gmap_translate(parent, paddr); if (IS_ERR_VALUE(vmaddr)) { rc = vmaddr; break; } rc = radix_tree_preload(GFP_KERNEL); if (rc) break; rc = -EAGAIN; sptep = gmap_pte_op_walk(parent, paddr, &ptl); if (sptep) { spin_lock(&sg->guest_table_lock); /* Get page table pointer */ tptep = (pte_t *) gmap_table_walk(sg, saddr, 0); if (!tptep) { spin_unlock(&sg->guest_table_lock); gmap_pte_op_end(ptl); radix_tree_preload_end(); break; } rc = ptep_shadow_pte(sg->mm, saddr, sptep, tptep, pte); if (rc > 0) { /* Success and a new mapping */ gmap_insert_rmap(sg, vmaddr, rmap); rmap = NULL; rc = 0; } gmap_pte_op_end(ptl); spin_unlock(&sg->guest_table_lock); } radix_tree_preload_end(); if (!rc) break; rc = gmap_pte_op_fixup(parent, paddr, vmaddr, prot); if (rc) break; } kfree(rmap); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky29289.57%360.00%
David Hildenbrand3410.43%240.00%
Total326100.00%5100.00%

EXPORT_SYMBOL_GPL(gmap_shadow_page); /** * gmap_shadow_notify - handle notifications for shadow gmap * * Called with sg->parent->shadow_lock. */
static void gmap_shadow_notify(struct gmap *sg, unsigned long vmaddr, unsigned long gaddr, pte_t *pte) { struct gmap_rmap *rmap, *rnext, *head; unsigned long start, end, bits, raddr; BUG_ON(!gmap_is_shadow(sg)); spin_lock(&sg->guest_table_lock); if (sg->removed) { spin_unlock(&sg->guest_table_lock); return; } /* Check for top level table */ start = sg->orig_asce & _ASCE_ORIGIN; end = start + ((sg->orig_asce & _ASCE_TABLE_LENGTH) + 1) * PAGE_SIZE; if (!(sg->orig_asce & _ASCE_REAL_SPACE) && gaddr >= start && gaddr < end) { /* The complete shadow table has to go */ gmap_unshadow(sg); spin_unlock(&sg->guest_table_lock); list_del(&sg->list); gmap_put(sg); return; } /* Remove the page table tree from on specific entry */ head = radix_tree_delete(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT); gmap_for_each_rmap_safe(rmap, rnext, head) { bits = rmap->raddr & _SHADOW_RMAP_MASK; raddr = rmap->raddr ^ bits; switch (bits) { case _SHADOW_RMAP_REGION1: gmap_unshadow_r2t(sg, raddr); break; case _SHADOW_RMAP_REGION2: gmap_unshadow_r3t(sg, raddr); break; case _SHADOW_RMAP_REGION3: gmap_unshadow_sgt(sg, raddr); break; case _SHADOW_RMAP_SEGMENT: gmap_unshadow_pgt(sg, raddr); break; case _SHADOW_RMAP_PGTABLE: gmap_unshadow_page(sg, raddr); break; } kfree(rmap); } spin_unlock(&sg->guest_table_lock); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky25795.54%350.00%
David Hildenbrand93.35%116.67%
Heiko Carstens20.74%116.67%
Janosch Frank10.37%116.67%
Total269100.00%6100.00%

/** * ptep_notify - call all invalidation callbacks for a specific pte. * @mm: pointer to the process mm_struct * @addr: virtual address in the process address space * @pte: pointer to the page table entry * @bits: bits from the pgste that caused the notify call * * This function is assumed to be called with the page table lock held * for the pte to notify. */
void ptep_notify(struct mm_struct *mm, unsigned long vmaddr, pte_t *pte, unsigned long bits) { unsigned long offset, gaddr = 0; unsigned long *table; struct gmap *gmap, *sg, *next; offset = ((unsigned long) pte) & (255 * sizeof(pte_t)); offset = offset * (PAGE_SIZE / sizeof(pte_t)); rcu_read_lock(); list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { spin_lock(&gmap->guest_table_lock); table = radix_tree_lookup(&gmap->host_to_guest, vmaddr >> PMD_SHIFT); if (table) gaddr = __gmap_segment_gaddr(table) + offset; spin_unlock(&gmap->guest_table_lock); if (!table) continue; if (!list_empty(&gmap->children) && (bits & PGSTE_VSIE_BIT)) { spin_lock(&gmap->shadow_lock); list_for_each_entry_safe(sg, next, &gmap->children, list) gmap_shadow_notify(sg, vmaddr, gaddr, pte); spin_unlock(&gmap->shadow_lock); } if (bits & PGSTE_IN_BIT) gmap_call_notifier(gmap, gaddr, gaddr + PAGE_SIZE - 1); } rcu_read_unlock(); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky16575.69%466.67%
Janosch Frank5223.85%116.67%
Heiko Carstens10.46%116.67%
Total218100.00%6100.00%

EXPORT_SYMBOL_GPL(ptep_notify);
static inline void thp_split_mm(struct mm_struct *mm) { #ifdef CONFIG_TRANSPARENT_HUGEPAGE struct vm_area_struct *vma; unsigned long addr; for (vma = mm->mmap; vma != NULL; vma = vma->vm_next) { for (addr = vma->vm_start; addr < vma->vm_end; addr += PAGE_SIZE) follow_page(vma, addr, FOLL_SPLIT); vma->vm_flags &= ~VM_HUGEPAGE; vma->vm_flags |= VM_NOHUGEPAGE; } mm->def_flags |= VM_NOHUGEPAGE; #endif }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky92100.00%1100.00%
Total92100.00%1100.00%

/* * Remove all empty zero pages from the mapping for lazy refaulting * - This must be called after mm->context.has_pgste is set, to avoid * future creation of zero pages * - This must be called after THP was enabled */
static int __zap_zero_pages(pmd_t *pmd, unsigned long start, unsigned long end, struct mm_walk *walk) { unsigned long addr; for (addr = start; addr != end; addr += PAGE_SIZE) { pte_t *ptep; spinlock_t *ptl; ptep = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); if (is_zero_pfn(pte_pfn(*ptep))) ptep_xchg_direct(walk->mm, addr, ptep, __pte(_PAGE_INVALID)); pte_unmap_unlock(ptep, ptl); } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Christian Bornträger104100.00%1100.00%
Total104100.00%1100.00%


static inline void zap_zero_pages(struct mm_struct *mm) { struct mm_walk walk = { .pmd_entry = __zap_zero_pages }; walk.mm = mm; walk_page_range(0, TASK_SIZE, &walk); }

Contributors

PersonTokensPropCommitsCommitProp
Christian Bornträger39100.00%1100.00%
Total39100.00%1100.00%

/* * switch on pgstes for its userspace process (for kvm) */
int s390_enable_sie(void) { struct mm_struct *mm = current->mm; /* Do we have pgstes? if yes, we are done */ if (mm_has_pgste(mm)) return 0; /* Fail if the page tables are 2K */ if (!mm_alloc_pgste(mm)) return -EINVAL; down_write(&mm->mmap_sem); mm->context.has_pgste = 1; /* split thp mappings and disable thp for future mappings */ thp_split_mm(mm); zap_zero_pages(mm); up_write(&mm->mmap_sem); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky7393.59%150.00%
Christian Bornträger56.41%150.00%
Total78100.00%2100.00%

EXPORT_SYMBOL_GPL(s390_enable_sie); /* * Enable storage key handling from now on and initialize the storage * keys with the default key. */
static int __s390_enable_skey(pte_t *pte, unsigned long addr, unsigned long next, struct mm_walk *walk) { /* Clear storage key */ ptep_zap_key(walk->mm, addr, pte); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky38100.00%1100.00%
Total38100.00%1100.00%


int s390_enable_skey(void) { struct mm_walk walk = { .pte_entry = __s390_enable_skey }; struct mm_struct *mm = current->mm; struct vm_area_struct *vma; int rc = 0; down_write(&mm->mmap_sem); if (mm_use_skey(mm)) goto out_up; mm->context.use_skey = 1; for (vma = mm->mmap; vma; vma = vma->vm_next) { if (ksm_madvise(vma, vma->vm_start, vma->vm_end, MADV_UNMERGEABLE, &vma->vm_flags)) { mm->context.use_skey = 0; rc = -ENOMEM; goto out_up; } } mm->def_flags &= ~VM_MERGEABLE; walk.mm = mm; walk_page_range(0, TASK_SIZE, &walk); out_up: up_write(&mm->mmap_sem); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky157100.00%1100.00%
Total157100.00%1100.00%

EXPORT_SYMBOL_GPL(s390_enable_skey); /* * Reset CMMA state, make all pages stable again. */
static int __s390_reset_cmma(pte_t *pte, unsigned long addr, unsigned long next, struct mm_walk *walk) { ptep_zap_unused(walk->mm, addr, pte, 1); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky39100.00%1100.00%
Total39100.00%1100.00%


void s390_reset_cmma(struct mm_struct *mm) { struct mm_walk walk = { .pte_entry = __s390_reset_cmma }; down_write(&mm->mmap_sem); walk.mm = mm; walk_page_range(0, TASK_SIZE, &walk); up_write(&mm->mmap_sem); }

Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky53100.00%1100.00%
Total53100.00%1100.00%

EXPORT_SYMBOL_GPL(s390_reset_cmma);

Overall Contributors

PersonTokensPropCommitsCommitProp
Martin Schwidefsky860086.89%1032.26%
David Hildenbrand9629.72%1341.94%
Christian Bornträger1531.55%26.45%
Heiko Carstens1091.10%26.45%
Janosch Frank530.54%13.23%
Gerald Schaefer130.13%13.23%
Johannes Weiner50.05%13.23%
Dominik Dingel30.03%13.23%
Total9898100.00%31100.00%
Directory: arch/s390/mm
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.