diff --git a/drivers/Makefile b/drivers/Makefile index 503d82569449..6d9d7fab77f5 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -15,6 +15,8 @@ obj-$(CONFIG_ACPI) += acpi/ obj-$(CONFIG_PNP) += pnp/ obj-$(CONFIG_ARM_AMBA) += amba/ +obj-$(CONFIG_XEN) += xen/ + # char/ comes before serial/ etc so that the VT console is the boot-time # default. obj-y += char/ diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile new file mode 100644 index 000000000000..eb42b521eef9 --- /dev/null +++ b/drivers/xen/Makefile @@ -0,0 +1 @@ +obj-y += grant-table.o diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c new file mode 100644 index 000000000000..ea94dbabf9a9 --- /dev/null +++ b/drivers/xen/grant-table.c @@ -0,0 +1,582 @@ +/****************************************************************************** + * grant_table.c + * + * Granting foreign access to our memory reservation. + * + * Copyright (c) 2005-2006, Christopher Clark + * Copyright (c) 2004-2005, K A Fraser + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation; or, when distributed + * separately from the Linux kernel or incorporated into other + * software packages, subject to the following license: + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this source file (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, modify, + * merge, publish, distribute, sublicense, and/or sell copies of the Software, + * and to permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#include +#include +#include +#include +#include + +#include +#include +#include + +#include +#include + + +/* External tools reserve first few grant table entries. */ +#define NR_RESERVED_ENTRIES 8 +#define GNTTAB_LIST_END 0xffffffff +#define GREFS_PER_GRANT_FRAME (PAGE_SIZE / sizeof(struct grant_entry)) + +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 DEFINE_SPINLOCK(gnttab_list_lock); + +static struct grant_entry *shared; + +static struct gnttab_free_callback *gnttab_free_callback_list; + +static int gnttab_expand(unsigned int req_entries); + +#define RPP (PAGE_SIZE / sizeof(grant_ref_t)) + +static inline grant_ref_t *__gnttab_entry(grant_ref_t entry) +{ + return &gnttab_list[(entry) / RPP][(entry) % RPP]; +} +/* This can be used as an l-value */ +#define gnttab_entry(entry) (*__gnttab_entry(entry)) + +static int get_free_entries(unsigned count) +{ + unsigned long flags; + int ref, rc; + grant_ref_t head; + + spin_lock_irqsave(&gnttab_list_lock, flags); + + if ((gnttab_free_count < count) && + ((rc = gnttab_expand(count - gnttab_free_count)) < 0)) { + spin_unlock_irqrestore(&gnttab_list_lock, flags); + return rc; + } + + 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; + + spin_unlock_irqrestore(&gnttab_list_lock, flags); + + return ref; +} + +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 (unlikely(gnttab_free_callback_list)) + do_free_callbacks(); +} + +static void put_free_entry(grant_ref_t ref) +{ + unsigned long flags; + spin_lock_irqsave(&gnttab_list_lock, flags); + gnttab_entry(ref) = gnttab_free_head; + gnttab_free_head = ref; + gnttab_free_count++; + check_free_callbacks(); + spin_unlock_irqrestore(&gnttab_list_lock, flags); +} + +static void update_grant_entry(grant_ref_t ref, domid_t domid, + unsigned long frame, unsigned flags) +{ + /* + * Introducing a valid entry into the grant table: + * 1. Write ent->domid. + * 2. Write ent->frame: + * GTF_permit_access: Frame to which access is permitted. + * GTF_accept_transfer: Pseudo-phys frame slot being filled by new + * frame, or zero if none. + * 3. Write memory barrier (WMB). + * 4. Write ent->flags, inc. valid type. + */ + shared[ref].frame = frame; + shared[ref].domid = domid; + wmb(); + shared[ref].flags = flags; +} + +/* + * Public grant-issuing interface functions + */ +void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid, + unsigned long frame, int readonly) +{ + update_grant_entry(ref, domid, frame, + GTF_permit_access | (readonly ? GTF_readonly : 0)); +} +EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_ref); + +int gnttab_grant_foreign_access(domid_t domid, unsigned long frame, + int readonly) +{ + int ref; + + ref = get_free_entries(1); + if (unlikely(ref < 0)) + return -ENOSPC; + + gnttab_grant_foreign_access_ref(ref, domid, frame, readonly); + + return ref; +} +EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access); + +int gnttab_query_foreign_access(grant_ref_t ref) +{ + u16 nflags; + + nflags = shared[ref].flags; + + return (nflags & (GTF_reading|GTF_writing)); +} +EXPORT_SYMBOL_GPL(gnttab_query_foreign_access); + +int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly) +{ + u16 flags, nflags; + + nflags = shared[ref].flags; + do { + flags = nflags; + if (flags & (GTF_reading|GTF_writing)) { + printk(KERN_ALERT "WARNING: g.e. still in use!\n"); + return 0; + } + } while ((nflags = sync_cmpxchg(&shared[ref].flags, flags, 0)) != flags); + + return 1; +} +EXPORT_SYMBOL_GPL(gnttab_end_foreign_access_ref); + +void gnttab_end_foreign_access(grant_ref_t ref, int readonly, + unsigned long page) +{ + if (gnttab_end_foreign_access_ref(ref, readonly)) { + put_free_entry(ref); + if (page != 0) + free_page(page); + } else { + /* XXX This needs to be fixed so that the ref and page are + placed on a list to be freed up later. */ + printk(KERN_WARNING + "WARNING: leaking g.e. and page still in use!\n"); + } +} +EXPORT_SYMBOL_GPL(gnttab_end_foreign_access); + +int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn) +{ + int ref; + + ref = get_free_entries(1); + if (unlikely(ref < 0)) + return -ENOSPC; + gnttab_grant_foreign_transfer_ref(ref, domid, pfn); + + return ref; +} +EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer); + +void gnttab_grant_foreign_transfer_ref(grant_ref_t ref, domid_t domid, + unsigned long pfn) +{ + update_grant_entry(ref, domid, pfn, GTF_accept_transfer); +} +EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer_ref); + +unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref) +{ + unsigned long frame; + u16 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 (sync_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(); + } + + rmb(); /* Read the frame number /after/ reading completion status. */ + frame = shared[ref].frame; + BUG_ON(frame == 0); + + return frame; +} +EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer_ref); + +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; +} +EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer); + +void gnttab_free_grant_reference(grant_ref_t ref) +{ + put_free_entry(ref); +} +EXPORT_SYMBOL_GPL(gnttab_free_grant_reference); + +void gnttab_free_grant_references(grant_ref_t head) +{ + grant_ref_t ref; + unsigned long flags; + int count = 1; + if (head == GNTTAB_LIST_END) + return; + spin_lock_irqsave(&gnttab_list_lock, flags); + ref = head; + while (gnttab_entry(ref) != GNTTAB_LIST_END) { + ref = gnttab_entry(ref); + count++; + } + gnttab_entry(ref) = gnttab_free_head; + gnttab_free_head = head; + gnttab_free_count += count; + check_free_callbacks(); + spin_unlock_irqrestore(&gnttab_list_lock, flags); +} +EXPORT_SYMBOL_GPL(gnttab_free_grant_references); + +int gnttab_alloc_grant_references(u16 count, grant_ref_t *head) +{ + int h = get_free_entries(count); + + if (h < 0) + return -ENOSPC; + + *head = h; + + return 0; +} +EXPORT_SYMBOL_GPL(gnttab_alloc_grant_references); + +int gnttab_empty_grant_references(const grant_ref_t *private_head) +{ + return (*private_head == GNTTAB_LIST_END); +} +EXPORT_SYMBOL_GPL(gnttab_empty_grant_references); + +int gnttab_claim_grant_reference(grant_ref_t *private_head) +{ + grant_ref_t g = *private_head; + if (unlikely(g == GNTTAB_LIST_END)) + return -ENOSPC; + *private_head = gnttab_entry(g); + return g; +} +EXPORT_SYMBOL_GPL(gnttab_claim_grant_reference); + +void gnttab_release_grant_reference(grant_ref_t *private_head, + grant_ref_t release) +{ + gnttab_entry(release) = *private_head; + *private_head = release; +} +EXPORT_SYMBOL_GPL(gnttab_release_grant_reference); + +void gnttab_request_free_callback(struct gnttab_free_callback *callback, + void (*fn)(void *), void *arg, u16 count) +{ + unsigned long flags; + spin_lock_irqsave(&gnttab_list_lock, flags); + 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: + spin_unlock_irqrestore(&gnttab_list_lock, flags); +} +EXPORT_SYMBOL_GPL(gnttab_request_free_callback); + +void gnttab_cancel_free_callback(struct gnttab_free_callback *callback) +{ + struct gnttab_free_callback **pcb; + unsigned long flags; + + spin_lock_irqsave(&gnttab_list_lock, flags); + for (pcb = &gnttab_free_callback_list; *pcb; pcb = &(*pcb)->next) { + if (*pcb == callback) { + *pcb = callback->next; + break; + } + } + spin_unlock_irqrestore(&gnttab_list_lock, flags); +} +EXPORT_SYMBOL_GPL(gnttab_cancel_free_callback); + +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 *)__get_free_page(GFP_ATOMIC); + 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_page((unsigned long) gnttab_list[i]); + 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; +} + +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, mfn_pte((*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; +} + +static int gnttab_map(unsigned int start_idx, unsigned int end_idx) +{ + struct gnttab_setup_table setup; + unsigned long *frames; + unsigned int nr_gframes = end_idx + 1; + int rc; + + frames = kmalloc(nr_gframes * sizeof(unsigned long), GFP_ATOMIC); + if (!frames) + return -ENOMEM; + + setup.dom = DOMID_SELF; + setup.nr_frames = nr_gframes; + setup.frame_list = frames; + + rc = HYPERVISOR_grant_table_op(GNTTABOP_setup_table, &setup, 1); + if (rc == -ENOSYS) { + kfree(frames); + return -ENOSYS; + } + + BUG_ON(rc || setup.status); + + if (shared == NULL) { + struct vm_struct *area; + area = alloc_vm_area(PAGE_SIZE * max_nr_grant_frames()); + BUG_ON(area == NULL); + shared = area->addr; + } + rc = apply_to_page_range(&init_mm, (unsigned long)shared, + PAGE_SIZE * nr_gframes, + map_pte_fn, &frames); + BUG_ON(rc); + frames -= nr_gframes; /* adjust after map_pte_fn() */ + + kfree(frames); + + return 0; +} + +static int gnttab_resume(void) +{ + if (max_nr_grant_frames() < nr_grant_frames) + return -ENOSYS; + return gnttab_map(0, nr_grant_frames - 1); +} + +static int gnttab_suspend(void) +{ + apply_to_page_range(&init_mm, (unsigned long)shared, + PAGE_SIZE * nr_grant_frames, + unmap_pte_fn, NULL); + + return 0; +} + +static int gnttab_expand(unsigned int req_entries) +{ + int rc; + 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; + + rc = gnttab_map(cur, cur + extra - 1); + if (rc == 0) + rc = grow_gnttab_list(extra); + + return rc; +} + +static int __devinit gnttab_init(void) +{ + 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 = kmalloc(max_nr_glist_frames * sizeof(grant_ref_t *), + GFP_KERNEL); + if (gnttab_list == NULL) + return -ENOMEM; + + for (i = 0; i < nr_grant_frames; i++) { + gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_KERNEL); + if (gnttab_list[i] == NULL) + goto ini_nomem; + } + + if (gnttab_resume() < 0) + 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; + + printk("Grant table initialized\n"); + return 0; + + ini_nomem: + for (i--; i >= 0; i--) + free_page((unsigned long)gnttab_list[i]); + kfree(gnttab_list); + return -ENOMEM; +} + +core_initcall(gnttab_init); diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h new file mode 100644 index 000000000000..761c83498e03 --- /dev/null +++ b/include/xen/grant_table.h @@ -0,0 +1,107 @@ +/****************************************************************************** + * grant_table.h + * + * 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) 2004-2005, K A Fraser + * Copyright (c) 2005, Christopher Clark + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation; or, when distributed + * separately from the Linux kernel or incorporated into other + * software packages, subject to the following license: + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this source file (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, modify, + * merge, publish, distribute, sublicense, and/or sell copies of the Software, + * and to permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#ifndef __ASM_GNTTAB_H__ +#define __ASM_GNTTAB_H__ + +#include +#include + +/* NR_GRANT_FRAMES must be less than or equal to that configured in Xen */ +#define NR_GRANT_FRAMES 4 + +struct gnttab_free_callback { + struct gnttab_free_callback *next; + void (*fn)(void *); + void *arg; + u16 count; +}; + +int gnttab_grant_foreign_access(domid_t domid, unsigned long frame, + int readonly); + +/* + * End access through the given grant reference, iff the grant entry is no + * longer in use. Return 1 if the grant entry was freed, 0 if it is still in + * use. + */ +int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly); + +/* + * Eventually end access through the given grant reference, and once that + * access has been ended, free the given page too. Access will be ended + * immediately iff the grant entry is not in use, otherwise it will happen + * some time later. page may be 0, in which case no freeing will occur. + */ +void gnttab_end_foreign_access(grant_ref_t ref, int readonly, + unsigned long page); + +int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn); + +unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref); +unsigned long gnttab_end_foreign_transfer(grant_ref_t ref); + +int gnttab_query_foreign_access(grant_ref_t ref); + +/* + * operations on reserved batches of grant references + */ +int gnttab_alloc_grant_references(u16 count, grant_ref_t *pprivate_head); + +void gnttab_free_grant_reference(grant_ref_t ref); + +void gnttab_free_grant_references(grant_ref_t head); + +int gnttab_empty_grant_references(const grant_ref_t *pprivate_head); + +int gnttab_claim_grant_reference(grant_ref_t *pprivate_head); + +void gnttab_release_grant_reference(grant_ref_t *private_head, + grant_ref_t release); + +void gnttab_request_free_callback(struct gnttab_free_callback *callback, + void (*fn)(void *), void *arg, u16 count); +void gnttab_cancel_free_callback(struct gnttab_free_callback *callback); + +void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid, + unsigned long frame, int readonly); + +void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid, + unsigned long pfn); + +#define gnttab_map_vaddr(map) ((void *)(map.host_virt_addr)) + +#endif /* __ASM_GNTTAB_H__ */ diff --git a/include/xen/interface/grant_table.h b/include/xen/interface/grant_table.h index e9e06695ed52..219049802cf2 100644 --- a/include/xen/interface/grant_table.h +++ b/include/xen/interface/grant_table.h @@ -4,6 +4,24 @@ * Interface for granting foreign access to page frames, and receiving * page-ownership transfers. * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to + * deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or + * sell copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + * * Copyright (c) 2004, K A Fraser */ @@ -17,7 +35,7 @@ /* Some rough guidelines on accessing and updating grant-table entries * in a concurrency-safe manner. For more information, Linux contains a - * reference implementation for guest OSes (arch/i386/mach-xen/grant_table.c). + * reference implementation for guest OSes (arch/xen/kernel/grant_table.c). * * NB. WMB is a no-op on current-generation x86 processors. However, a * compiler barrier will still be required. @@ -144,9 +162,9 @@ typedef uint32_t grant_handle_t; * that must be presented later to destroy the mapping(s). On error, * is a negative status code. * NOTES: - * 1. If GNTPIN_map_for_dev is specified then is the address + * 1. If GNTMAP_device_map is specified then is the address * via which I/O devices may access the granted frame. - * 2. If GNTPIN_map_for_host is specified then a mapping will be added at + * 2. If GNTMAP_host_map is specified then a mapping will be added at * either a host virtual address in the current address space, or at * a PTE at the specified machine address. The type of mapping to * perform is selected through the GNTMAP_contains_pte flag, and the @@ -167,7 +185,6 @@ struct gnttab_map_grant_ref { grant_handle_t handle; uint64_t dev_bus_addr; }; -DEFINE_GUEST_HANDLE_STRUCT(gnttab_map_grant_ref); /* * GNTTABOP_unmap_grant_ref: Destroy one or more grant-reference mappings @@ -189,7 +206,6 @@ struct gnttab_unmap_grant_ref { /* OUT parameters. */ int16_t status; /* GNTST_* */ }; -DEFINE_GUEST_HANDLE_STRUCT(gnttab_unmap_grant_ref); /* * GNTTABOP_setup_table: Set up a grant table for comprising at least @@ -207,9 +223,8 @@ struct gnttab_setup_table { uint32_t nr_frames; /* OUT parameters. */ int16_t status; /* GNTST_* */ - GUEST_HANDLE(ulong) frame_list; + ulong *frame_list; }; -DEFINE_GUEST_HANDLE_STRUCT(gnttab_setup_table); /* * GNTTABOP_dump_table: Dump the contents of the grant table to the @@ -222,7 +237,6 @@ struct gnttab_dump_table { /* OUT parameters. */ int16_t status; /* GNTST_* */ }; -DEFINE_GUEST_HANDLE_STRUCT(gnttab_dump_table); /* * GNTTABOP_transfer_grant_ref: Transfer to a foreign domain. The @@ -241,7 +255,65 @@ struct gnttab_transfer { /* OUT parameters. */ int16_t status; }; -DEFINE_GUEST_HANDLE_STRUCT(gnttab_transfer); + + +/* + * GNTTABOP_copy: Hypervisor based copy + * source and destinations can be eithers MFNs or, for foreign domains, + * grant references. the foreign domain has to grant read/write access + * in its grant table. + * + * The flags specify what type source and destinations are (either MFN + * or grant reference). + * + * Note that this can also be used to copy data between two domains + * via a third party if the source and destination domains had previously + * grant appropriate access to their pages to the third party. + * + * source_offset specifies an offset in the source frame, dest_offset + * the offset in the target frame and len specifies the number of + * bytes to be copied. + */ + +#define _GNTCOPY_source_gref (0) +#define GNTCOPY_source_gref (1<<_GNTCOPY_source_gref) +#define _GNTCOPY_dest_gref (1) +#define GNTCOPY_dest_gref (1<<_GNTCOPY_dest_gref) + +#define GNTTABOP_copy 5 +struct gnttab_copy { + /* IN parameters. */ + struct { + union { + grant_ref_t ref; + unsigned long gmfn; + } u; + domid_t domid; + uint16_t offset; + } source, dest; + uint16_t len; + uint16_t flags; /* GNTCOPY_* */ + /* OUT parameters. */ + int16_t status; +}; + +/* + * GNTTABOP_query_size: Query the current and maximum sizes of the shared + * grant table. + * NOTES: + * 1. may be specified as DOMID_SELF. + * 2. Only a sufficiently-privileged domain may specify != DOMID_SELF. + */ +#define GNTTABOP_query_size 6 +struct gnttab_query_size { + /* IN parameters. */ + domid_t dom; + /* OUT parameters. */ + uint32_t nr_frames; + uint32_t max_nr_frames; + int16_t status; /* GNTST_* */ +}; + /* * Bitfield values for update_pin_status.flags. @@ -284,6 +356,7 @@ DEFINE_GUEST_HANDLE_STRUCT(gnttab_transfer); #define GNTST_no_device_space (-7) /* Out of space in I/O MMU. */ #define GNTST_permission_denied (-8) /* Not enough privilege for operation. */ #define GNTST_bad_page (-9) /* Specified page was invalid for op. */ +#define GNTST_bad_copy_arg (-10) /* copy arguments cross page boundary */ #define GNTTABOP_error_msgs { \ "okay", \ @@ -295,7 +368,8 @@ DEFINE_GUEST_HANDLE_STRUCT(gnttab_transfer); "invalid device address", \ "no spare translation slot in the I/O MMU", \ "permission denied", \ - "bad page" \ + "bad page", \ + "copy arguments cross page boundary" \ } #endif /* __XEN_PUBLIC_GRANT_TABLE_H__ */