Merge branches 'stable/p2m-identity.v4.9.1' and 'stable/e820' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

* 'stable/p2m-identity.v4.9.1' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/m2p: Check whether the MFN has IDENTITY_FRAME bit set..
  xen/m2p: No need to catch exceptions when we know that there is no RAM
  xen/debug: WARN_ON when identity PFN has no _PAGE_IOMAP flag set.
  xen/debugfs: Add 'p2m' file for printing out the P2M layout.
  xen/setup: Set identity mapping for non-RAM E820 and E820 gaps.
  xen/mmu: WARN_ON when racing to swap middle leaf.
  xen/mmu: Set _PAGE_IOMAP if PFN is an identity PFN.
  xen/mmu: Add the notion of identity (1-1) mapping.
  xen: Mark all initial reserved pages for the balloon as INVALID_P2M_ENTRY.

* 'stable/e820' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/e820: Don't mark balloon memory as E820_UNUSABLE when running as guest and fix overflow.
  xen/setup: Inhibit resource API from using System RAM E820 gaps as PCI mem gaps.
This commit is contained in:
Linus Torvalds
2011-03-15 10:32:15 -07:00
6 changed files with 498 additions and 21 deletions

View File

@@ -29,8 +29,10 @@ typedef struct xpaddr {
/**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/
#define INVALID_P2M_ENTRY (~0UL)
#define FOREIGN_FRAME_BIT (1UL<<31)
#define FOREIGN_FRAME_BIT (1UL<<(BITS_PER_LONG-1))
#define IDENTITY_FRAME_BIT (1UL<<(BITS_PER_LONG-2))
#define FOREIGN_FRAME(m) ((m) | FOREIGN_FRAME_BIT)
#define IDENTITY_FRAME(m) ((m) | IDENTITY_FRAME_BIT)
/* Maximum amount of memory we can handle in a domain in pages */
#define MAX_DOMAIN_PAGES \
@@ -41,12 +43,18 @@ extern unsigned int machine_to_phys_order;
extern unsigned long get_phys_to_machine(unsigned long pfn);
extern bool set_phys_to_machine(unsigned long pfn, unsigned long mfn);
extern bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn);
extern unsigned long set_phys_range_identity(unsigned long pfn_s,
unsigned long pfn_e);
extern int m2p_add_override(unsigned long mfn, struct page *page);
extern int m2p_remove_override(struct page *page);
extern struct page *m2p_find_override(unsigned long mfn);
extern unsigned long m2p_find_override_pfn(unsigned long mfn, unsigned long pfn);
#ifdef CONFIG_XEN_DEBUG_FS
extern int p2m_dump_show(struct seq_file *m, void *v);
#endif
static inline unsigned long pfn_to_mfn(unsigned long pfn)
{
unsigned long mfn;
@@ -57,7 +65,7 @@ static inline unsigned long pfn_to_mfn(unsigned long pfn)
mfn = get_phys_to_machine(pfn);
if (mfn != INVALID_P2M_ENTRY)
mfn &= ~FOREIGN_FRAME_BIT;
mfn &= ~(FOREIGN_FRAME_BIT | IDENTITY_FRAME_BIT);
return mfn;
}
@@ -73,25 +81,44 @@ static inline int phys_to_machine_mapping_valid(unsigned long pfn)
static inline unsigned long mfn_to_pfn(unsigned long mfn)
{
unsigned long pfn;
int ret = 0;
if (xen_feature(XENFEAT_auto_translated_physmap))
return mfn;
if (unlikely((mfn >> machine_to_phys_order) != 0)) {
pfn = ~0;
goto try_override;
}
pfn = 0;
/*
* The array access can fail (e.g., device space beyond end of RAM).
* In such cases it doesn't matter what we return (we return garbage),
* but we must handle the fault without crashing!
*/
__get_user(pfn, &machine_to_phys_mapping[mfn]);
ret = __get_user(pfn, &machine_to_phys_mapping[mfn]);
try_override:
/* ret might be < 0 if there are no entries in the m2p for mfn */
if (ret < 0)
pfn = ~0;
else if (get_phys_to_machine(pfn) != mfn)
/*
* If this appears to be a foreign mfn (because the pfn
* doesn't map back to the mfn), then check the local override
* table to see if there's a better pfn to use.
*
* m2p_find_override_pfn returns ~0 if it doesn't find anything.
*/
pfn = m2p_find_override_pfn(mfn, ~0);
/*
* If this appears to be a foreign mfn (because the pfn
* doesn't map back to the mfn), then check the local override
* table to see if there's a better pfn to use.
/*
* pfn is ~0 if there are no entries in the m2p for mfn or if the
* entry doesn't map back to the mfn and m2p_override doesn't have a
* valid entry for it.
*/
if (get_phys_to_machine(pfn) != mfn)
pfn = m2p_find_override_pfn(mfn, pfn);
if (pfn == ~0 &&
get_phys_to_machine(mfn) == IDENTITY_FRAME(mfn))
pfn = mfn;
return pfn;
}