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authorRoger Pau Monné <royger@FreeBSD.org>2014-12-10 11:21:52 +0000
committerRoger Pau Monné <royger@FreeBSD.org>2014-12-10 11:21:52 +0000
commit0767e98a2dc3b3309eebb051139c8b6c35991f8a (patch)
treef762e8cef4912851e1dfe74d0786e3da656f1b68 /sys/xen
parent2c4f16476d2b44a072e8bfbb158c44879f59d463 (diff)
downloadsrc-0767e98a2dc3b3309eebb051139c8b6c35991f8a.tar.gz
src-0767e98a2dc3b3309eebb051139c8b6c35991f8a.zip
Notes
Diffstat (limited to 'sys/xen')
-rw-r--r--sys/xen/gnttab.c720
1 files changed, 0 insertions, 720 deletions
diff --git a/sys/xen/gnttab.c b/sys/xen/gnttab.c
deleted file mode 100644
index 9ab3145b4fee..000000000000
--- a/sys/xen/gnttab.c
+++ /dev/null
@@ -1,720 +0,0 @@
-/******************************************************************************
- * gnttab.c
- *
- * Two sets of functionality:
- * 1. Granting foreign access to our memory reservation.
- * 2. Accessing others' memory reservations via grant references.
- * (i.e., mechanisms for both sender and recipient of grant references)
- *
- * Copyright (c) 2005, Christopher Clark
- * Copyright (c) 2004, K A Fraser
- */
-
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD$");
-
-#include "opt_pmap.h"
-
-#include <sys/param.h>
-#include <sys/systm.h>
-#include <sys/bus.h>
-#include <sys/conf.h>
-#include <sys/module.h>
-#include <sys/kernel.h>
-#include <sys/lock.h>
-#include <sys/malloc.h>
-#include <sys/mman.h>
-#include <sys/limits.h>
-#include <sys/rman.h>
-#include <machine/resource.h>
-
-#include <xen/xen-os.h>
-#include <xen/hypervisor.h>
-#include <machine/xen/synch_bitops.h>
-
-#include <xen/hypervisor.h>
-#include <xen/gnttab.h>
-
-#include <vm/vm.h>
-#include <vm/vm_kern.h>
-#include <vm/vm_extern.h>
-#include <vm/pmap.h>
-
-#define cmpxchg(a, b, c) atomic_cmpset_int((volatile u_int *)(a),(b),(c))
-
-/* External tools reserve first few grant table entries. */
-#define NR_RESERVED_ENTRIES 8
-#define GREFS_PER_GRANT_FRAME (PAGE_SIZE / sizeof(grant_entry_t))
-
-static grant_ref_t **gnttab_list;
-static unsigned int nr_grant_frames;
-static unsigned int boot_max_nr_grant_frames;
-static int gnttab_free_count;
-static grant_ref_t gnttab_free_head;
-static struct mtx gnttab_list_lock;
-
-#ifdef XENHVM
-/*
- * Resource representing allocated physical address space
- * for the grant table metainfo
- */
-static struct resource *gnttab_pseudo_phys_res;
-
-/* Resource id for allocated physical address space. */
-static int gnttab_pseudo_phys_res_id;
-#endif
-
-static grant_entry_t *shared;
-
-static struct gnttab_free_callback *gnttab_free_callback_list = NULL;
-
-static int gnttab_expand(unsigned int req_entries);
-
-#define RPP (PAGE_SIZE / sizeof(grant_ref_t))
-#define gnttab_entry(entry) (gnttab_list[(entry) / RPP][(entry) % RPP])
-
-static int
-get_free_entries(int count, int *entries)
-{
- int ref, error;
- grant_ref_t head;
-
- mtx_lock(&gnttab_list_lock);
- if ((gnttab_free_count < count) &&
- ((error = gnttab_expand(count - gnttab_free_count)) != 0)) {
- mtx_unlock(&gnttab_list_lock);
- return (error);
- }
- ref = head = gnttab_free_head;
- gnttab_free_count -= count;
- while (count-- > 1)
- head = gnttab_entry(head);
- gnttab_free_head = gnttab_entry(head);
- gnttab_entry(head) = GNTTAB_LIST_END;
- mtx_unlock(&gnttab_list_lock);
-
- *entries = ref;
- return (0);
-}
-
-static void
-do_free_callbacks(void)
-{
- struct gnttab_free_callback *callback, *next;
-
- callback = gnttab_free_callback_list;
- gnttab_free_callback_list = NULL;
-
- while (callback != NULL) {
- next = callback->next;
- if (gnttab_free_count >= callback->count) {
- callback->next = NULL;
- callback->fn(callback->arg);
- } else {
- callback->next = gnttab_free_callback_list;
- gnttab_free_callback_list = callback;
- }
- callback = next;
- }
-}
-
-static inline void
-check_free_callbacks(void)
-{
- if (__predict_false(gnttab_free_callback_list != NULL))
- do_free_callbacks();
-}
-
-static void
-put_free_entry(grant_ref_t ref)
-{
-
- mtx_lock(&gnttab_list_lock);
- gnttab_entry(ref) = gnttab_free_head;
- gnttab_free_head = ref;
- gnttab_free_count++;
- check_free_callbacks();
- mtx_unlock(&gnttab_list_lock);
-}
-
-/*
- * Public grant-issuing interface functions
- */
-
-int
-gnttab_grant_foreign_access(domid_t domid, unsigned long frame, int readonly,
- grant_ref_t *result)
-{
- int error, ref;
-
- error = get_free_entries(1, &ref);
-
- if (__predict_false(error))
- return (error);
-
- shared[ref].frame = frame;
- shared[ref].domid = domid;
- wmb();
- shared[ref].flags = GTF_permit_access | (readonly ? GTF_readonly : 0);
-
- if (result)
- *result = ref;
-
- return (0);
-}
-
-void
-gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
- unsigned long frame, int readonly)
-{
-
- shared[ref].frame = frame;
- shared[ref].domid = domid;
- wmb();
- shared[ref].flags = GTF_permit_access | (readonly ? GTF_readonly : 0);
-}
-
-int
-gnttab_query_foreign_access(grant_ref_t ref)
-{
- uint16_t nflags;
-
- nflags = shared[ref].flags;
-
- return (nflags & (GTF_reading|GTF_writing));
-}
-
-int
-gnttab_end_foreign_access_ref(grant_ref_t ref)
-{
- uint16_t flags, nflags;
-
- nflags = shared[ref].flags;
- do {
- if ( (flags = nflags) & (GTF_reading|GTF_writing) ) {
- printf("%s: WARNING: g.e. still in use!\n", __func__);
- return (0);
- }
- } while ((nflags = synch_cmpxchg(&shared[ref].flags, flags, 0)) !=
- flags);
-
- return (1);
-}
-
-void
-gnttab_end_foreign_access(grant_ref_t ref, void *page)
-{
- if (gnttab_end_foreign_access_ref(ref)) {
- put_free_entry(ref);
- if (page != NULL) {
- free(page, M_DEVBUF);
- }
- }
- else {
- /* XXX This needs to be fixed so that the ref and page are
- placed on a list to be freed up later. */
- printf("%s: WARNING: leaking g.e. and page still in use!\n",
- __func__);
- }
-}
-
-void
-gnttab_end_foreign_access_references(u_int count, grant_ref_t *refs)
-{
- grant_ref_t *last_ref;
- grant_ref_t head;
- grant_ref_t tail;
-
- head = GNTTAB_LIST_END;
- tail = *refs;
- last_ref = refs + count;
- while (refs != last_ref) {
-
- if (gnttab_end_foreign_access_ref(*refs)) {
- gnttab_entry(*refs) = head;
- head = *refs;
- } else {
- /*
- * XXX This needs to be fixed so that the ref
- * is placed on a list to be freed up later.
- */
- printf("%s: WARNING: leaking g.e. still in use!\n",
- __func__);
- count--;
- }
- refs++;
- }
-
- if (count != 0) {
- mtx_lock(&gnttab_list_lock);
- gnttab_free_count += count;
- gnttab_entry(tail) = gnttab_free_head;
- gnttab_free_head = head;
- mtx_unlock(&gnttab_list_lock);
- }
-}
-
-int
-gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn,
- grant_ref_t *result)
-{
- int error, ref;
-
- error = get_free_entries(1, &ref);
- if (__predict_false(error))
- return (error);
-
- gnttab_grant_foreign_transfer_ref(ref, domid, pfn);
-
- *result = ref;
- return (0);
-}
-
-void
-gnttab_grant_foreign_transfer_ref(grant_ref_t ref, domid_t domid,
- unsigned long pfn)
-{
- shared[ref].frame = pfn;
- shared[ref].domid = domid;
- wmb();
- shared[ref].flags = GTF_accept_transfer;
-}
-
-unsigned long
-gnttab_end_foreign_transfer_ref(grant_ref_t ref)
-{
- unsigned long frame;
- uint16_t flags;
-
- /*
- * If a transfer is not even yet started, try to reclaim the grant
- * reference and return failure (== 0).
- */
- while (!((flags = shared[ref].flags) & GTF_transfer_committed)) {
- if ( synch_cmpxchg(&shared[ref].flags, flags, 0) == flags )
- return (0);
- cpu_relax();
- }
-
- /* If a transfer is in progress then wait until it is completed. */
- while (!(flags & GTF_transfer_completed)) {
- flags = shared[ref].flags;
- cpu_relax();
- }
-
- /* Read the frame number /after/ reading completion status. */
- rmb();
- frame = shared[ref].frame;
- KASSERT(frame != 0, ("grant table inconsistent"));
-
- return (frame);
-}
-
-unsigned long
-gnttab_end_foreign_transfer(grant_ref_t ref)
-{
- unsigned long frame = gnttab_end_foreign_transfer_ref(ref);
-
- put_free_entry(ref);
- return (frame);
-}
-
-void
-gnttab_free_grant_reference(grant_ref_t ref)
-{
-
- put_free_entry(ref);
-}
-
-void
-gnttab_free_grant_references(grant_ref_t head)
-{
- grant_ref_t ref;
- int count = 1;
-
- if (head == GNTTAB_LIST_END)
- return;
-
- ref = head;
- while (gnttab_entry(ref) != GNTTAB_LIST_END) {
- ref = gnttab_entry(ref);
- count++;
- }
- mtx_lock(&gnttab_list_lock);
- gnttab_entry(ref) = gnttab_free_head;
- gnttab_free_head = head;
- gnttab_free_count += count;
- check_free_callbacks();
- mtx_unlock(&gnttab_list_lock);
-}
-
-int
-gnttab_alloc_grant_references(uint16_t count, grant_ref_t *head)
-{
- int ref, error;
-
- error = get_free_entries(count, &ref);
- if (__predict_false(error))
- return (error);
-
- *head = ref;
- return (0);
-}
-
-int
-gnttab_empty_grant_references(const grant_ref_t *private_head)
-{
-
- return (*private_head == GNTTAB_LIST_END);
-}
-
-int
-gnttab_claim_grant_reference(grant_ref_t *private_head)
-{
- grant_ref_t g = *private_head;
-
- if (__predict_false(g == GNTTAB_LIST_END))
- return (g);
- *private_head = gnttab_entry(g);
- return (g);
-}
-
-void
-gnttab_release_grant_reference(grant_ref_t *private_head, grant_ref_t release)
-{
-
- gnttab_entry(release) = *private_head;
- *private_head = release;
-}
-
-void
-gnttab_request_free_callback(struct gnttab_free_callback *callback,
- void (*fn)(void *), void *arg, uint16_t count)
-{
-
- mtx_lock(&gnttab_list_lock);
- if (callback->next)
- goto out;
- callback->fn = fn;
- callback->arg = arg;
- callback->count = count;
- callback->next = gnttab_free_callback_list;
- gnttab_free_callback_list = callback;
- check_free_callbacks();
- out:
- mtx_unlock(&gnttab_list_lock);
-
-}
-
-void
-gnttab_cancel_free_callback(struct gnttab_free_callback *callback)
-{
- struct gnttab_free_callback **pcb;
-
- mtx_lock(&gnttab_list_lock);
- for (pcb = &gnttab_free_callback_list; *pcb; pcb = &(*pcb)->next) {
- if (*pcb == callback) {
- *pcb = callback->next;
- break;
- }
- }
- mtx_unlock(&gnttab_list_lock);
-}
-
-
-static int
-grow_gnttab_list(unsigned int more_frames)
-{
- unsigned int new_nr_grant_frames, extra_entries, i;
-
- new_nr_grant_frames = nr_grant_frames + more_frames;
- extra_entries = more_frames * GREFS_PER_GRANT_FRAME;
-
- for (i = nr_grant_frames; i < new_nr_grant_frames; i++)
- {
- gnttab_list[i] = (grant_ref_t *)
- malloc(PAGE_SIZE, M_DEVBUF, M_NOWAIT);
-
- if (!gnttab_list[i])
- goto grow_nomem;
- }
-
- for (i = GREFS_PER_GRANT_FRAME * nr_grant_frames;
- i < GREFS_PER_GRANT_FRAME * new_nr_grant_frames - 1; i++)
- gnttab_entry(i) = i + 1;
-
- gnttab_entry(i) = gnttab_free_head;
- gnttab_free_head = GREFS_PER_GRANT_FRAME * nr_grant_frames;
- gnttab_free_count += extra_entries;
-
- nr_grant_frames = new_nr_grant_frames;
-
- check_free_callbacks();
-
- return (0);
-
-grow_nomem:
- for ( ; i >= nr_grant_frames; i--)
- free(gnttab_list[i], M_DEVBUF);
- return (ENOMEM);
-}
-
-static unsigned int
-__max_nr_grant_frames(void)
-{
- struct gnttab_query_size query;
- int rc;
-
- query.dom = DOMID_SELF;
-
- rc = HYPERVISOR_grant_table_op(GNTTABOP_query_size, &query, 1);
- if ((rc < 0) || (query.status != GNTST_okay))
- return (4); /* Legacy max supported number of frames */
-
- return (query.max_nr_frames);
-}
-
-static inline
-unsigned int max_nr_grant_frames(void)
-{
- unsigned int xen_max = __max_nr_grant_frames();
-
- if (xen_max > boot_max_nr_grant_frames)
- return (boot_max_nr_grant_frames);
- return (xen_max);
-}
-
-#ifdef notyet
-/*
- * XXX needed for backend support
- *
- */
-static int
-map_pte_fn(pte_t *pte, struct page *pmd_page,
- unsigned long addr, void *data)
-{
- unsigned long **frames = (unsigned long **)data;
-
- set_pte_at(&init_mm, addr, pte, pfn_pte_ma((*frames)[0], PAGE_KERNEL));
- (*frames)++;
- return 0;
-}
-
-static int
-unmap_pte_fn(pte_t *pte, struct page *pmd_page,
- unsigned long addr, void *data)
-{
-
- set_pte_at(&init_mm, addr, pte, __pte(0));
- return 0;
-}
-#endif
-
-#ifndef XENHVM
-
-static int
-gnttab_map(unsigned int start_idx, unsigned int end_idx)
-{
- struct gnttab_setup_table setup;
- u_long *frames;
-
- unsigned int nr_gframes = end_idx + 1;
- int i, rc;
-
- frames = malloc(nr_gframes * sizeof(unsigned long), M_DEVBUF, M_NOWAIT);
- if (!frames)
- return (ENOMEM);
-
- setup.dom = DOMID_SELF;
- setup.nr_frames = nr_gframes;
- set_xen_guest_handle(setup.frame_list, frames);
-
- rc = HYPERVISOR_grant_table_op(GNTTABOP_setup_table, &setup, 1);
- if (rc == -ENOSYS) {
- free(frames, M_DEVBUF);
- return (ENOSYS);
- }
- KASSERT(!(rc || setup.status),
- ("unexpected result from grant_table_op"));
-
- if (shared == NULL) {
- vm_offset_t area;
-
- area = kva_alloc(PAGE_SIZE * max_nr_grant_frames());
- KASSERT(area, ("can't allocate VM space for grant table"));
- shared = (grant_entry_t *)area;
- }
-
- for (i = 0; i < nr_gframes; i++)
- PT_SET_MA(((caddr_t)shared) + i*PAGE_SIZE,
- ((vm_paddr_t)frames[i]) << PAGE_SHIFT | PG_RW | PG_V);
-
- free(frames, M_DEVBUF);
-
- return (0);
-}
-
-int
-gnttab_resume(device_t dev)
-{
-
- if (max_nr_grant_frames() < nr_grant_frames)
- return (ENOSYS);
- return (gnttab_map(0, nr_grant_frames - 1));
-}
-
-int
-gnttab_suspend(void)
-{
- int i;
-
- for (i = 0; i < nr_grant_frames; i++)
- pmap_kremove((vm_offset_t) shared + i * PAGE_SIZE);
-
- return (0);
-}
-
-#else /* XENHVM */
-
-static vm_paddr_t resume_frames;
-
-static int
-gnttab_map(unsigned int start_idx, unsigned int end_idx)
-{
- struct xen_add_to_physmap xatp;
- unsigned int i = end_idx;
-
- /*
- * Loop backwards, so that the first hypercall has the largest index,
- * ensuring that the table will grow only once.
- */
- do {
- xatp.domid = DOMID_SELF;
- xatp.idx = i;
- xatp.space = XENMAPSPACE_grant_table;
- xatp.gpfn = (resume_frames >> PAGE_SHIFT) + i;
- if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
- panic("HYPERVISOR_memory_op failed to map gnttab");
- } while (i-- > start_idx);
-
- if (shared == NULL) {
- vm_offset_t area;
-
- area = kva_alloc(PAGE_SIZE * max_nr_grant_frames());
- KASSERT(area, ("can't allocate VM space for grant table"));
- shared = (grant_entry_t *)area;
- }
-
- for (i = start_idx; i <= end_idx; i++) {
- pmap_kenter((vm_offset_t) shared + i * PAGE_SIZE,
- resume_frames + i * PAGE_SIZE);
- }
-
- return (0);
-}
-
-int
-gnttab_resume(device_t dev)
-{
- unsigned int max_nr_gframes, nr_gframes;
-
- nr_gframes = nr_grant_frames;
- max_nr_gframes = max_nr_grant_frames();
- if (max_nr_gframes < nr_gframes)
- return (ENOSYS);
-
- if (!resume_frames) {
- KASSERT(dev != NULL,
- ("No resume frames and no device provided"));
-
- gnttab_pseudo_phys_res = bus_alloc_resource(dev,
- SYS_RES_MEMORY, &gnttab_pseudo_phys_res_id, 0, ~0,
- PAGE_SIZE * max_nr_gframes, RF_ACTIVE);
- if (gnttab_pseudo_phys_res == NULL)
- panic("Unable to reserve physical memory for gnttab");
- resume_frames = rman_get_start(gnttab_pseudo_phys_res);
- }
-
- return (gnttab_map(0, nr_gframes - 1));
-}
-
-#endif
-
-static int
-gnttab_expand(unsigned int req_entries)
-{
- int error;
- unsigned int cur, extra;
-
- cur = nr_grant_frames;
- extra = ((req_entries + (GREFS_PER_GRANT_FRAME-1)) /
- GREFS_PER_GRANT_FRAME);
- if (cur + extra > max_nr_grant_frames())
- return (ENOSPC);
-
- error = gnttab_map(cur, cur + extra - 1);
- if (!error)
- error = grow_gnttab_list(extra);
-
- return (error);
-}
-
-int
-gnttab_init(device_t dev)
-{
- int i;
- unsigned int max_nr_glist_frames;
- unsigned int nr_init_grefs;
-
- if (!is_running_on_xen())
- return (ENODEV);
-
- nr_grant_frames = 1;
- boot_max_nr_grant_frames = __max_nr_grant_frames();
-
- /* Determine the maximum number of frames required for the
- * grant reference free list on the current hypervisor.
- */
- max_nr_glist_frames = (boot_max_nr_grant_frames *
- GREFS_PER_GRANT_FRAME /
- (PAGE_SIZE / sizeof(grant_ref_t)));
-
- gnttab_list = malloc(max_nr_glist_frames * sizeof(grant_ref_t *),
- M_DEVBUF, M_NOWAIT);
-
- if (gnttab_list == NULL)
- return (ENOMEM);
-
- for (i = 0; i < nr_grant_frames; i++) {
- gnttab_list[i] = (grant_ref_t *)
- malloc(PAGE_SIZE, M_DEVBUF, M_NOWAIT);
- if (gnttab_list[i] == NULL)
- goto ini_nomem;
- }
-
- if (gnttab_resume(dev))
- return (ENODEV);
-
- nr_init_grefs = nr_grant_frames * GREFS_PER_GRANT_FRAME;
-
- for (i = NR_RESERVED_ENTRIES; i < nr_init_grefs - 1; i++)
- gnttab_entry(i) = i + 1;
-
- gnttab_entry(nr_init_grefs - 1) = GNTTAB_LIST_END;
- gnttab_free_count = nr_init_grefs - NR_RESERVED_ENTRIES;
- gnttab_free_head = NR_RESERVED_ENTRIES;
-
- if (bootverbose)
- printf("Grant table initialized\n");
-
- return (0);
-
-ini_nomem:
- for (i--; i >= 0; i--)
- free(gnttab_list[i], M_DEVBUF);
- free(gnttab_list, M_DEVBUF);
- return (ENOMEM);
-
-}
-
-MTX_SYSINIT(gnttab, &gnttab_list_lock, "GNTTAB LOCK", MTX_DEF);