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xen: Make functions static 

Some functions in arch/x86/xen/p2m.c are used locally only. Make them
static. Rearrange the functions in p2m.c to avoid forward declarations.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
This commit is contained in:
Juergen Gross 2014-11-28 11:53:51 +01:00 committed by David Vrabel
parent 6f58d89e6c
commit 820c4db2be
2 changed files with 103 additions and 111 deletions
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6
arch/x86/include/asm/xen/page.h
View File

@ -52,15 +52,9 @@ extern unsigned long set_phys_range_identity(unsigned long pfn_s,
extern int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, extern int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
struct gnttab_map_grant_ref *kmap_ops, struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count); struct page **pages, unsigned int count);
extern int m2p_add_override(unsigned long mfn, struct page *page,
struct gnttab_map_grant_ref *kmap_op);
extern int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, extern int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
struct gnttab_map_grant_ref *kmap_ops, struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count); struct page **pages, unsigned int count);
extern int m2p_remove_override(struct page *page,
struct gnttab_map_grant_ref *kmap_op,
unsigned long mfn);
extern struct page *m2p_find_override(unsigned long mfn);
extern unsigned long m2p_find_override_pfn(unsigned long mfn, unsigned long pfn); extern unsigned long m2p_find_override_pfn(unsigned long mfn, unsigned long pfn);
static inline unsigned long pfn_to_mfn(unsigned long pfn) static inline unsigned long pfn_to_mfn(unsigned long pfn)

208
arch/x86/xen/p2m.c
View File

@ -896,6 +896,61 @@ static unsigned long mfn_hash(unsigned long mfn)
return hash_long(mfn, M2P_OVERRIDE_HASH_SHIFT); return hash_long(mfn, M2P_OVERRIDE_HASH_SHIFT);
} }
/* Add an MFN override for a particular page */
static int m2p_add_override(unsigned long mfn, struct page *page,
struct gnttab_map_grant_ref *kmap_op)
{
unsigned long flags;
unsigned long pfn;
unsigned long uninitialized_var(address);
unsigned level;
pte_t *ptep = NULL;
pfn = page_to_pfn(page);
if (!PageHighMem(page)) {
address = (unsigned long)__va(pfn << PAGE_SHIFT);
ptep = lookup_address(address, &level);
if (WARN(ptep == NULL || level != PG_LEVEL_4K,
"m2p_add_override: pfn %lx not mapped", pfn))
return -EINVAL;
}
if (kmap_op != NULL) {
if (!PageHighMem(page)) {
struct multicall_space mcs =
xen_mc_entry(sizeof(*kmap_op));
MULTI_grant_table_op(mcs.mc,
GNTTABOP_map_grant_ref, kmap_op, 1);
xen_mc_issue(PARAVIRT_LAZY_MMU);
}
}
spin_lock_irqsave(&m2p_override_lock, flags);
list_add(&page->lru, &m2p_overrides[mfn_hash(mfn)]);
spin_unlock_irqrestore(&m2p_override_lock, flags);
/* p2m(m2p(mfn)) == mfn: the mfn is already present somewhere in
* this domain. Set the FOREIGN_FRAME_BIT in the p2m for the other
* pfn so that the following mfn_to_pfn(mfn) calls will return the
* pfn from the m2p_override (the backend pfn) instead.
* We need to do this because the pages shared by the frontend
* (xen-blkfront) can be already locked (lock_page, called by
* do_read_cache_page); when the userspace backend tries to use them
* with direct_IO, mfn_to_pfn returns the pfn of the frontend, so
* do_blockdev_direct_IO is going to try to lock the same pages
* again resulting in a deadlock.
* As a side effect get_user_pages_fast might not be safe on the
* frontend pages while they are being shared with the backend,
* because mfn_to_pfn (that ends up being called by GUPF) will
* return the backend pfn rather than the frontend pfn. */
pfn = mfn_to_pfn_no_overrides(mfn);
if (get_phys_to_machine(pfn) == mfn)
set_phys_to_machine(pfn, FOREIGN_FRAME(mfn));
return 0;
}
int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
struct gnttab_map_grant_ref *kmap_ops, struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count) struct page **pages, unsigned int count)
@ -955,109 +1010,31 @@ int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
} }
EXPORT_SYMBOL_GPL(set_foreign_p2m_mapping); EXPORT_SYMBOL_GPL(set_foreign_p2m_mapping);
/* Add an MFN override for a particular page */ static struct page *m2p_find_override(unsigned long mfn)
int m2p_add_override(unsigned long mfn, struct page *page,
struct gnttab_map_grant_ref *kmap_op)
{ {
unsigned long flags; unsigned long flags;
unsigned long pfn; struct list_head *bucket = &m2p_overrides[mfn_hash(mfn)];
unsigned long uninitialized_var(address); struct page *p, *ret;
unsigned level;
pte_t *ptep = NULL;
pfn = page_to_pfn(page); ret = NULL;
if (!PageHighMem(page)) {
address = (unsigned long)__va(pfn << PAGE_SHIFT);
ptep = lookup_address(address, &level);
if (WARN(ptep == NULL || level != PG_LEVEL_4K,
"m2p_add_override: pfn %lx not mapped", pfn))
return -EINVAL;
}
if (kmap_op != NULL) { spin_lock_irqsave(&m2p_override_lock, flags);
if (!PageHighMem(page)) {
struct multicall_space mcs =
xen_mc_entry(sizeof(*kmap_op));
MULTI_grant_table_op(mcs.mc, list_for_each_entry(p, bucket, lru) {
GNTTABOP_map_grant_ref, kmap_op, 1); if (page_private(p) == mfn) {
ret = p;
xen_mc_issue(PARAVIRT_LAZY_MMU); break;
} }
} }
spin_lock_irqsave(&m2p_override_lock, flags);
list_add(&page->lru, &m2p_overrides[mfn_hash(mfn)]);
spin_unlock_irqrestore(&m2p_override_lock, flags); spin_unlock_irqrestore(&m2p_override_lock, flags);
/* p2m(m2p(mfn)) == mfn: the mfn is already present somewhere in
* this domain. Set the FOREIGN_FRAME_BIT in the p2m for the other
* pfn so that the following mfn_to_pfn(mfn) calls will return the
* pfn from the m2p_override (the backend pfn) instead.
* We need to do this because the pages shared by the frontend
* (xen-blkfront) can be already locked (lock_page, called by
* do_read_cache_page); when the userspace backend tries to use them
* with direct_IO, mfn_to_pfn returns the pfn of the frontend, so
* do_blockdev_direct_IO is going to try to lock the same pages
* again resulting in a deadlock.
* As a side effect get_user_pages_fast might not be safe on the
* frontend pages while they are being shared with the backend,
* because mfn_to_pfn (that ends up being called by GUPF) will
* return the backend pfn rather than the frontend pfn. */
pfn = mfn_to_pfn_no_overrides(mfn);
if (get_phys_to_machine(pfn) == mfn)
set_phys_to_machine(pfn, FOREIGN_FRAME(mfn));
return 0;
}
EXPORT_SYMBOL_GPL(m2p_add_override);
int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count)
{
int i, ret = 0;
bool lazy = false;
if (xen_feature(XENFEAT_auto_translated_physmap))
return 0;
if (kmap_ops &&
!in_interrupt() &&
paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) {
arch_enter_lazy_mmu_mode();
lazy = true;
}
for (i = 0; i < count; i++) {
unsigned long mfn = get_phys_to_machine(page_to_pfn(pages[i]));
unsigned long pfn = page_to_pfn(pages[i]);
if (mfn == INVALID_P2M_ENTRY || !(mfn & FOREIGN_FRAME_BIT)) {
ret = -EINVAL;
goto out;
}
set_page_private(pages[i], INVALID_P2M_ENTRY);
WARN_ON(!PagePrivate(pages[i]));
ClearPagePrivate(pages[i]);
set_phys_to_machine(pfn, pages[i]->index);
if (kmap_ops)
ret = m2p_remove_override(pages[i], &kmap_ops[i], mfn);
if (ret)
goto out;
}
out:
if (lazy)
arch_leave_lazy_mmu_mode();
return ret; return ret;
} }
EXPORT_SYMBOL_GPL(clear_foreign_p2m_mapping);
int m2p_remove_override(struct page *page, static int m2p_remove_override(struct page *page,
struct gnttab_map_grant_ref *kmap_op, struct gnttab_map_grant_ref *kmap_op,
unsigned long mfn) unsigned long mfn)
{ {
unsigned long flags; unsigned long flags;
unsigned long pfn; unsigned long pfn;
@ -1150,29 +1127,50 @@ int m2p_remove_override(struct page *page,
return 0; return 0;
} }
EXPORT_SYMBOL_GPL(m2p_remove_override);
struct page *m2p_find_override(unsigned long mfn) int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count)
{ {
unsigned long flags; int i, ret = 0;
struct list_head *bucket = &m2p_overrides[mfn_hash(mfn)]; bool lazy = false;
struct page *p, *ret;
ret = NULL; if (xen_feature(XENFEAT_auto_translated_physmap))
return 0;
spin_lock_irqsave(&m2p_override_lock, flags); if (kmap_ops &&
!in_interrupt() &&
list_for_each_entry(p, bucket, lru) { paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) {
if (page_private(p) == mfn) { arch_enter_lazy_mmu_mode();
ret = p; lazy = true;
break;
}
} }
spin_unlock_irqrestore(&m2p_override_lock, flags); for (i = 0; i < count; i++) {
unsigned long mfn = get_phys_to_machine(page_to_pfn(pages[i]));
unsigned long pfn = page_to_pfn(pages[i]);
if (mfn == INVALID_P2M_ENTRY || !(mfn & FOREIGN_FRAME_BIT)) {
ret = -EINVAL;
goto out;
}
set_page_private(pages[i], INVALID_P2M_ENTRY);
WARN_ON(!PagePrivate(pages[i]));
ClearPagePrivate(pages[i]);
set_phys_to_machine(pfn, pages[i]->index);
if (kmap_ops)
ret = m2p_remove_override(pages[i], &kmap_ops[i], mfn);
if (ret)
goto out;
}
out:
if (lazy)
arch_leave_lazy_mmu_mode();
return ret; return ret;
} }
EXPORT_SYMBOL_GPL(clear_foreign_p2m_mapping);
unsigned long m2p_find_override_pfn(unsigned long mfn, unsigned long pfn) unsigned long m2p_find_override_pfn(unsigned long mfn, unsigned long pfn)
{ {