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linux/arch/x86/kernel/amd_iommu.c
Joerg Roedel d7f0776975 x86/amd-iommu: Fall back to GART if initialization fails 
This patch implements a fallback to the GART IOMMU if this
is possible and the AMD IOMMU initialization failed.
Otherwise the fallback would be nommu which is very
problematic on machines with more than 4GB of memory or
swiotlb which hurts io-performance.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2010-06-01 10:20:15 +02:00

2630 lines
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/*
* Copyright (C) 2007-2009 Advanced Micro Devices, Inc.
* Author: Joerg Roedel <joerg.roedel@amd.com>
* Leo Duran <leo.duran@amd.com>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/pci.h>
#include <linux/bitmap.h>
#include <linux/slab.h>
#include <linux/debugfs.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <linux/iommu-helper.h>
#include <linux/iommu.h>
#include <asm/proto.h>
#include <asm/iommu.h>
#include <asm/gart.h>
#include <asm/amd_iommu_proto.h>
#include <asm/amd_iommu_types.h>
#include <asm/amd_iommu.h>
#define CMD_SET_TYPE(cmd, t) ((cmd)->data[1] |= ((t) << 28))
#define EXIT_LOOP_COUNT 10000000
static DEFINE_RWLOCK(amd_iommu_devtable_lock);
/* A list of preallocated protection domains */
static LIST_HEAD(iommu_pd_list);
static DEFINE_SPINLOCK(iommu_pd_list_lock);
/*
* Domain for untranslated devices - only allocated
* if iommu=pt passed on kernel cmd line.
*/
static struct protection_domain *pt_domain;
static struct iommu_ops amd_iommu_ops;
/*
* general struct to manage commands send to an IOMMU
*/
struct iommu_cmd {
u32 data[4];
};
static void reset_iommu_command_buffer(struct amd_iommu *iommu);
static void update_domain(struct protection_domain *domain);
/****************************************************************************
*
* Helper functions
*
****************************************************************************/
static inline u16 get_device_id(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
return calc_devid(pdev->bus->number, pdev->devfn);
}
static struct iommu_dev_data *get_dev_data(struct device *dev)
{
return dev->archdata.iommu;
}
/*
* In this function the list of preallocated protection domains is traversed to
* find the domain for a specific device
*/
static struct dma_ops_domain *find_protection_domain(u16 devid)
{
struct dma_ops_domain *entry, *ret = NULL;
unsigned long flags;
u16 alias = amd_iommu_alias_table[devid];
if (list_empty(&iommu_pd_list))
return NULL;
spin_lock_irqsave(&iommu_pd_list_lock, flags);
list_for_each_entry(entry, &iommu_pd_list, list) {
if (entry->target_dev == devid ||
entry->target_dev == alias) {
ret = entry;
break;
}
}
spin_unlock_irqrestore(&iommu_pd_list_lock, flags);
return ret;
}
/*
* This function checks if the driver got a valid device from the caller to
* avoid dereferencing invalid pointers.
*/
static bool check_device(struct device *dev)
{
u16 devid;
if (!dev || !dev->dma_mask)
return false;
/* No device or no PCI device */
if (dev->bus != &pci_bus_type)
return false;
devid = get_device_id(dev);
/* Out of our scope? */
if (devid > amd_iommu_last_bdf)
return false;
if (amd_iommu_rlookup_table[devid] == NULL)
return false;
return true;
}
static int iommu_init_device(struct device *dev)
{
struct iommu_dev_data *dev_data;
struct pci_dev *pdev;
u16 devid, alias;
if (dev->archdata.iommu)
return 0;
dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL);
if (!dev_data)
return -ENOMEM;
dev_data->dev = dev;
devid = get_device_id(dev);
alias = amd_iommu_alias_table[devid];
pdev = pci_get_bus_and_slot(PCI_BUS(alias), alias & 0xff);
if (pdev)
dev_data->alias = &pdev->dev;
atomic_set(&dev_data->bind, 0);
dev->archdata.iommu = dev_data;
return 0;
}
static void iommu_uninit_device(struct device *dev)
{
kfree(dev->archdata.iommu);
}
void __init amd_iommu_uninit_devices(void)
{
struct pci_dev *pdev = NULL;
for_each_pci_dev(pdev) {
if (!check_device(&pdev->dev))
continue;
iommu_uninit_device(&pdev->dev);
}
}
int __init amd_iommu_init_devices(void)
{
struct pci_dev *pdev = NULL;
int ret = 0;
for_each_pci_dev(pdev) {
if (!check_device(&pdev->dev))
continue;
ret = iommu_init_device(&pdev->dev);
if (ret)
goto out_free;
}
return 0;
out_free:
amd_iommu_uninit_devices();
return ret;
}
#ifdef CONFIG_AMD_IOMMU_STATS
/*
* Initialization code for statistics collection
*/
DECLARE_STATS_COUNTER(compl_wait);
DECLARE_STATS_COUNTER(cnt_map_single);
DECLARE_STATS_COUNTER(cnt_unmap_single);
DECLARE_STATS_COUNTER(cnt_map_sg);
DECLARE_STATS_COUNTER(cnt_unmap_sg);
DECLARE_STATS_COUNTER(cnt_alloc_coherent);
DECLARE_STATS_COUNTER(cnt_free_coherent);
DECLARE_STATS_COUNTER(cross_page);
DECLARE_STATS_COUNTER(domain_flush_single);
DECLARE_STATS_COUNTER(domain_flush_all);
DECLARE_STATS_COUNTER(alloced_io_mem);
DECLARE_STATS_COUNTER(total_map_requests);
static struct dentry *stats_dir;
static struct dentry *de_fflush;
static void amd_iommu_stats_add(struct __iommu_counter *cnt)
{
if (stats_dir == NULL)
return;
cnt->dent = debugfs_create_u64(cnt->name, 0444, stats_dir,
&cnt->value);
}
static void amd_iommu_stats_init(void)
{
stats_dir = debugfs_create_dir("amd-iommu", NULL);
if (stats_dir == NULL)
return;
de_fflush = debugfs_create_bool("fullflush", 0444, stats_dir,
(u32 *)&amd_iommu_unmap_flush);
amd_iommu_stats_add(&compl_wait);
amd_iommu_stats_add(&cnt_map_single);
amd_iommu_stats_add(&cnt_unmap_single);
amd_iommu_stats_add(&cnt_map_sg);
amd_iommu_stats_add(&cnt_unmap_sg);
amd_iommu_stats_add(&cnt_alloc_coherent);
amd_iommu_stats_add(&cnt_free_coherent);
amd_iommu_stats_add(&cross_page);
amd_iommu_stats_add(&domain_flush_single);
amd_iommu_stats_add(&domain_flush_all);
amd_iommu_stats_add(&alloced_io_mem);
amd_iommu_stats_add(&total_map_requests);
}
#endif
/****************************************************************************
*
* Interrupt handling functions
*
****************************************************************************/
static void dump_dte_entry(u16 devid)
{
int i;
for (i = 0; i < 8; ++i)
pr_err("AMD-Vi: DTE[%d]: %08x\n", i,
amd_iommu_dev_table[devid].data[i]);
}
static void dump_command(unsigned long phys_addr)
{
struct iommu_cmd *cmd = phys_to_virt(phys_addr);
int i;
for (i = 0; i < 4; ++i)
pr_err("AMD-Vi: CMD[%d]: %08x\n", i, cmd->data[i]);
}
static void iommu_print_event(struct amd_iommu *iommu, void *__evt)
{
u32 *event = __evt;
int type = (event[1] >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
int devid = (event[0] >> EVENT_DEVID_SHIFT) & EVENT_DEVID_MASK;
int domid = (event[1] >> EVENT_DOMID_SHIFT) & EVENT_DOMID_MASK;
int flags = (event[1] >> EVENT_FLAGS_SHIFT) & EVENT_FLAGS_MASK;
u64 address = (u64)(((u64)event[3]) << 32) | event[2];
printk(KERN_ERR "AMD-Vi: Event logged [");
switch (type) {
case EVENT_TYPE_ILL_DEV:
printk("ILLEGAL_DEV_TABLE_ENTRY device=%02x:%02x.%x "
"address=0x%016llx flags=0x%04x]\n",
PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
address, flags);
dump_dte_entry(devid);
break;
case EVENT_TYPE_IO_FAULT:
printk("IO_PAGE_FAULT device=%02x:%02x.%x "
"domain=0x%04x address=0x%016llx flags=0x%04x]\n",
PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
domid, address, flags);
break;
case EVENT_TYPE_DEV_TAB_ERR:
printk("DEV_TAB_HARDWARE_ERROR device=%02x:%02x.%x "
"address=0x%016llx flags=0x%04x]\n",
PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
address, flags);
break;
case EVENT_TYPE_PAGE_TAB_ERR:
printk("PAGE_TAB_HARDWARE_ERROR device=%02x:%02x.%x "
"domain=0x%04x address=0x%016llx flags=0x%04x]\n",
PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
domid, address, flags);
break;
case EVENT_TYPE_ILL_CMD:
printk("ILLEGAL_COMMAND_ERROR address=0x%016llx]\n", address);
iommu->reset_in_progress = true;
reset_iommu_command_buffer(iommu);
dump_command(address);
break;
case EVENT_TYPE_CMD_HARD_ERR:
printk("COMMAND_HARDWARE_ERROR address=0x%016llx "
"flags=0x%04x]\n", address, flags);
break;
case EVENT_TYPE_IOTLB_INV_TO:
printk("IOTLB_INV_TIMEOUT device=%02x:%02x.%x "
"address=0x%016llx]\n",
PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
address);
break;
case EVENT_TYPE_INV_DEV_REQ:
printk("INVALID_DEVICE_REQUEST device=%02x:%02x.%x "
"address=0x%016llx flags=0x%04x]\n",
PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
address, flags);
break;
default:
printk(KERN_ERR "UNKNOWN type=0x%02x]\n", type);
}
}
static void iommu_poll_events(struct amd_iommu *iommu)
{
u32 head, tail;
unsigned long flags;
spin_lock_irqsave(&iommu->lock, flags);
head = readl(iommu->mmio_base + MMIO_EVT_HEAD_OFFSET);
tail = readl(iommu->mmio_base + MMIO_EVT_TAIL_OFFSET);
while (head != tail) {
iommu_print_event(iommu, iommu->evt_buf + head);
head = (head + EVENT_ENTRY_SIZE) % iommu->evt_buf_size;
}
writel(head, iommu->mmio_base + MMIO_EVT_HEAD_OFFSET);
spin_unlock_irqrestore(&iommu->lock, flags);
}
irqreturn_t amd_iommu_int_handler(int irq, void *data)
{
struct amd_iommu *iommu;
for_each_iommu(iommu)
iommu_poll_events(iommu);
return IRQ_HANDLED;
}
/****************************************************************************
*
* IOMMU command queuing functions
*
****************************************************************************/
/*
* Writes the command to the IOMMUs command buffer and informs the
* hardware about the new command. Must be called with iommu->lock held.
*/
static int __iommu_queue_command(struct amd_iommu *iommu, struct iommu_cmd *cmd)
{
u32 tail, head;
u8 *target;
WARN_ON(iommu->cmd_buf_size & CMD_BUFFER_UNINITIALIZED);
tail = readl(iommu->mmio_base + MMIO_CMD_TAIL_OFFSET);
target = iommu->cmd_buf + tail;
memcpy_toio(target, cmd, sizeof(*cmd));
tail = (tail + sizeof(*cmd)) % iommu->cmd_buf_size;
head = readl(iommu->mmio_base + MMIO_CMD_HEAD_OFFSET);
if (tail == head)
return -ENOMEM;
writel(tail, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET);
return 0;
}
/*
* General queuing function for commands. Takes iommu->lock and calls
* __iommu_queue_command().
*/
static int iommu_queue_command(struct amd_iommu *iommu, struct iommu_cmd *cmd)
{
unsigned long flags;
int ret;
spin_lock_irqsave(&iommu->lock, flags);
ret = __iommu_queue_command(iommu, cmd);
if (!ret)
iommu->need_sync = true;
spin_unlock_irqrestore(&iommu->lock, flags);
return ret;
}
/*
* This function waits until an IOMMU has completed a completion
* wait command
*/
static void __iommu_wait_for_completion(struct amd_iommu *iommu)
{
int ready = 0;
unsigned status = 0;
unsigned long i = 0;
INC_STATS_COUNTER(compl_wait);
while (!ready && (i < EXIT_LOOP_COUNT)) {
++i;
/* wait for the bit to become one */
status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET);
ready = status & MMIO_STATUS_COM_WAIT_INT_MASK;
}
/* set bit back to zero */
status &= ~MMIO_STATUS_COM_WAIT_INT_MASK;
writel(status, iommu->mmio_base + MMIO_STATUS_OFFSET);
if (unlikely(i == EXIT_LOOP_COUNT))
iommu->reset_in_progress = true;
}
/*
* This function queues a completion wait command into the command
* buffer of an IOMMU
*/
static int __iommu_completion_wait(struct amd_iommu *iommu)
{
struct iommu_cmd cmd;
memset(&cmd, 0, sizeof(cmd));
cmd.data[0] = CMD_COMPL_WAIT_INT_MASK;
CMD_SET_TYPE(&cmd, CMD_COMPL_WAIT);
return __iommu_queue_command(iommu, &cmd);
}
/*
* This function is called whenever we need to ensure that the IOMMU has
* completed execution of all commands we sent. It sends a
* COMPLETION_WAIT command and waits for it to finish. The IOMMU informs
* us about that by writing a value to a physical address we pass with
* the command.
*/
static int iommu_completion_wait(struct amd_iommu *iommu)
{
int ret = 0;
unsigned long flags;
spin_lock_irqsave(&iommu->lock, flags);
if (!iommu->need_sync)
goto out;
ret = __iommu_completion_wait(iommu);
iommu->need_sync = false;
if (ret)
goto out;
__iommu_wait_for_completion(iommu);
out:
spin_unlock_irqrestore(&iommu->lock, flags);
if (iommu->reset_in_progress)
reset_iommu_command_buffer(iommu);
return 0;
}
static void iommu_flush_complete(struct protection_domain *domain)
{
int i;
for (i = 0; i < amd_iommus_present; ++i) {
if (!domain->dev_iommu[i])
continue;
/*
* Devices of this domain are behind this IOMMU
* We need to wait for completion of all commands.
*/
iommu_completion_wait(amd_iommus[i]);
}
}
/*
* Command send function for invalidating a device table entry
*/
static int iommu_flush_device(struct device *dev)
{
struct amd_iommu *iommu;
struct iommu_cmd cmd;
u16 devid;
devid = get_device_id(dev);
iommu = amd_iommu_rlookup_table[devid];
/* Build command */
memset(&cmd, 0, sizeof(cmd));
CMD_SET_TYPE(&cmd, CMD_INV_DEV_ENTRY);
cmd.data[0] = devid;
return iommu_queue_command(iommu, &cmd);
}
static void __iommu_build_inv_iommu_pages(struct iommu_cmd *cmd, u64 address,
u16 domid, int pde, int s)
{
memset(cmd, 0, sizeof(*cmd));
address &= PAGE_MASK;
CMD_SET_TYPE(cmd, CMD_INV_IOMMU_PAGES);
cmd->data[1] |= domid;
cmd->data[2] = lower_32_bits(address);
cmd->data[3] = upper_32_bits(address);
if (s) /* size bit - we flush more than one 4kb page */
cmd->data[2] |= CMD_INV_IOMMU_PAGES_SIZE_MASK;
if (pde) /* PDE bit - we wan't flush everything not only the PTEs */
cmd->data[2] |= CMD_INV_IOMMU_PAGES_PDE_MASK;
}
/*
* Generic command send function for invalidaing TLB entries
*/
static int iommu_queue_inv_iommu_pages(struct amd_iommu *iommu,
u64 address, u16 domid, int pde, int s)
{
struct iommu_cmd cmd;
int ret;
__iommu_build_inv_iommu_pages(&cmd, address, domid, pde, s);
ret = iommu_queue_command(iommu, &cmd);
return ret;
}
/*
* TLB invalidation function which is called from the mapping functions.
* It invalidates a single PTE if the range to flush is within a single
* page. Otherwise it flushes the whole TLB of the IOMMU.
*/
static void __iommu_flush_pages(struct protection_domain *domain,
u64 address, size_t size, int pde)
{
int s = 0, i;
unsigned long pages = iommu_num_pages(address, size, PAGE_SIZE);
address &= PAGE_MASK;
if (pages > 1) {
/*
* If we have to flush more than one page, flush all
* TLB entries for this domain
*/
address = CMD_INV_IOMMU_ALL_PAGES_ADDRESS;
s = 1;
}
for (i = 0; i < amd_iommus_present; ++i) {
if (!domain->dev_iommu[i])
continue;
/*
* Devices of this domain are behind this IOMMU
* We need a TLB flush
*/
iommu_queue_inv_iommu_pages(amd_iommus[i], address,
domain->id, pde, s);
}
return;
}
static void iommu_flush_pages(struct protection_domain *domain,
u64 address, size_t size)
{
__iommu_flush_pages(domain, address, size, 0);
}
/* Flush the whole IO/TLB for a given protection domain */
static void iommu_flush_tlb(struct protection_domain *domain)
{
__iommu_flush_pages(domain, 0, CMD_INV_IOMMU_ALL_PAGES_ADDRESS, 0);
}
/* Flush the whole IO/TLB for a given protection domain - including PDE */
static void iommu_flush_tlb_pde(struct protection_domain *domain)
{
__iommu_flush_pages(domain, 0, CMD_INV_IOMMU_ALL_PAGES_ADDRESS, 1);
}
/*
* This function flushes the DTEs for all devices in domain
*/
static void iommu_flush_domain_devices(struct protection_domain *domain)
{
struct iommu_dev_data *dev_data;
unsigned long flags;
spin_lock_irqsave(&domain->lock, flags);
list_for_each_entry(dev_data, &domain->dev_list, list)
iommu_flush_device(dev_data->dev);
spin_unlock_irqrestore(&domain->lock, flags);
}
static void iommu_flush_all_domain_devices(void)
{
struct protection_domain *domain;
unsigned long flags;
spin_lock_irqsave(&amd_iommu_pd_lock, flags);
list_for_each_entry(domain, &amd_iommu_pd_list, list) {
iommu_flush_domain_devices(domain);
iommu_flush_complete(domain);
}
spin_unlock_irqrestore(&amd_iommu_pd_lock, flags);
}
void amd_iommu_flush_all_devices(void)
{
iommu_flush_all_domain_devices();
}
/*
* This function uses heavy locking and may disable irqs for some time. But
* this is no issue because it is only called during resume.
*/
void amd_iommu_flush_all_domains(void)
{
struct protection_domain *domain;
unsigned long flags;
spin_lock_irqsave(&amd_iommu_pd_lock, flags);
list_for_each_entry(domain, &amd_iommu_pd_list, list) {
spin_lock(&domain->lock);
iommu_flush_tlb_pde(domain);
iommu_flush_complete(domain);
spin_unlock(&domain->lock);
}
spin_unlock_irqrestore(&amd_iommu_pd_lock, flags);
}
static void reset_iommu_command_buffer(struct amd_iommu *iommu)
{
pr_err("AMD-Vi: Resetting IOMMU command buffer\n");
if (iommu->reset_in_progress)
panic("AMD-Vi: ILLEGAL_COMMAND_ERROR while resetting command buffer\n");
amd_iommu_reset_cmd_buffer(iommu);
amd_iommu_flush_all_devices();
amd_iommu_flush_all_domains();
iommu->reset_in_progress = false;
}
/****************************************************************************
*
* The functions below are used the create the page table mappings for
* unity mapped regions.
*
****************************************************************************/
/*
* This function is used to add another level to an IO page table. Adding
* another level increases the size of the address space by 9 bits to a size up
* to 64 bits.
*/
static bool increase_address_space(struct protection_domain *domain,
gfp_t gfp)
{
u64 *pte;
if (domain->mode == PAGE_MODE_6_LEVEL)
/* address space already 64 bit large */
return false;
pte = (void *)get_zeroed_page(gfp);
if (!pte)
return false;
*pte = PM_LEVEL_PDE(domain->mode,
virt_to_phys(domain->pt_root));
domain->pt_root = pte;
domain->mode += 1;
domain->updated = true;
return true;
}
static u64 *alloc_pte(struct protection_domain *domain,
unsigned long address,
unsigned long page_size,
u64 **pte_page,
gfp_t gfp)
{
int level, end_lvl;
u64 *pte, *page;
BUG_ON(!is_power_of_2(page_size));
while (address > PM_LEVEL_SIZE(domain->mode))
increase_address_space(domain, gfp);
level = domain->mode - 1;
pte = &domain->pt_root[PM_LEVEL_INDEX(level, address)];
address = PAGE_SIZE_ALIGN(address, page_size);
end_lvl = PAGE_SIZE_LEVEL(page_size);
while (level > end_lvl) {
if (!IOMMU_PTE_PRESENT(*pte)) {
page = (u64 *)get_zeroed_page(gfp);
if (!page)
return NULL;
*pte = PM_LEVEL_PDE(level, virt_to_phys(page));
}
/* No level skipping support yet */
if (PM_PTE_LEVEL(*pte) != level)
return NULL;
level -= 1;
pte = IOMMU_PTE_PAGE(*pte);
if (pte_page && level == end_lvl)
*pte_page = pte;
pte = &pte[PM_LEVEL_INDEX(level, address)];
}
return pte;
}
/*
* This function checks if there is a PTE for a given dma address. If
* there is one, it returns the pointer to it.
*/
static u64 *fetch_pte(struct protection_domain *domain, unsigned long address)
{
int level;
u64 *pte;
if (address > PM_LEVEL_SIZE(domain->mode))
return NULL;
level = domain->mode - 1;
pte = &domain->pt_root[PM_LEVEL_INDEX(level, address)];
while (level > 0) {
/* Not Present */
if (!IOMMU_PTE_PRESENT(*pte))
return NULL;
/* Large PTE */
if (PM_PTE_LEVEL(*pte) == 0x07) {
unsigned long pte_mask, __pte;
/*
* If we have a series of large PTEs, make
* sure to return a pointer to the first one.
*/
pte_mask = PTE_PAGE_SIZE(*pte);
pte_mask = ~((PAGE_SIZE_PTE_COUNT(pte_mask) << 3) - 1);
__pte = ((unsigned long)pte) & pte_mask;
return (u64 *)__pte;
}
/* No level skipping support yet */
if (PM_PTE_LEVEL(*pte) != level)
return NULL;
level -= 1;
/* Walk to the next level */
pte = IOMMU_PTE_PAGE(*pte);
pte = &pte[PM_LEVEL_INDEX(level, address)];
}
return pte;
}
/*
* Generic mapping functions. It maps a physical address into a DMA
* address space. It allocates the page table pages if necessary.
* In the future it can be extended to a generic mapping function
* supporting all features of AMD IOMMU page tables like level skipping
* and full 64 bit address spaces.
*/
static int iommu_map_page(struct protection_domain *dom,
unsigned long bus_addr,
unsigned long phys_addr,
int prot,
unsigned long page_size)
{
u64 __pte, *pte;
int i, count;
if (!(prot & IOMMU_PROT_MASK))
return -EINVAL;
bus_addr = PAGE_ALIGN(bus_addr);
phys_addr = PAGE_ALIGN(phys_addr);
count = PAGE_SIZE_PTE_COUNT(page_size);
pte = alloc_pte(dom, bus_addr, page_size, NULL, GFP_KERNEL);
for (i = 0; i < count; ++i)
if (IOMMU_PTE_PRESENT(pte[i]))
return -EBUSY;
if (page_size > PAGE_SIZE) {
__pte = PAGE_SIZE_PTE(phys_addr, page_size);
__pte |= PM_LEVEL_ENC(7) | IOMMU_PTE_P | IOMMU_PTE_FC;
} else
__pte = phys_addr | IOMMU_PTE_P | IOMMU_PTE_FC;
if (prot & IOMMU_PROT_IR)
__pte |= IOMMU_PTE_IR;
if (prot & IOMMU_PROT_IW)
__pte |= IOMMU_PTE_IW;
for (i = 0; i < count; ++i)
pte[i] = __pte;
update_domain(dom);
return 0;
}
static unsigned long iommu_unmap_page(struct protection_domain *dom,
unsigned long bus_addr,
unsigned long page_size)
{
unsigned long long unmap_size, unmapped;
u64 *pte;
BUG_ON(!is_power_of_2(page_size));
unmapped = 0;
while (unmapped < page_size) {
pte = fetch_pte(dom, bus_addr);
if (!pte) {
/*
* No PTE for this address
* move forward in 4kb steps
*/
unmap_size = PAGE_SIZE;
} else if (PM_PTE_LEVEL(*pte) == 0) {
/* 4kb PTE found for this address */
unmap_size = PAGE_SIZE;
*pte = 0ULL;
} else {
int count, i;
/* Large PTE found which maps this address */
unmap_size = PTE_PAGE_SIZE(*pte);
count = PAGE_SIZE_PTE_COUNT(unmap_size);
for (i = 0; i < count; i++)
pte[i] = 0ULL;
}
bus_addr = (bus_addr & ~(unmap_size - 1)) + unmap_size;
unmapped += unmap_size;
}
BUG_ON(!is_power_of_2(unmapped));
return unmapped;
}
/*
* This function checks if a specific unity mapping entry is needed for
* this specific IOMMU.
*/
static int iommu_for_unity_map(struct amd_iommu *iommu,
struct unity_map_entry *entry)
{
u16 bdf, i;
for (i = entry->devid_start; i <= entry->devid_end; ++i) {
bdf = amd_iommu_alias_table[i];
if (amd_iommu_rlookup_table[bdf] == iommu)
return 1;
}
return 0;
}
/*
* This function actually applies the mapping to the page table of the
* dma_ops domain.
*/
static int dma_ops_unity_map(struct dma_ops_domain *dma_dom,
struct unity_map_entry *e)
{
u64 addr;
int ret;
for (addr = e->address_start; addr < e->address_end;
addr += PAGE_SIZE) {
ret = iommu_map_page(&dma_dom->domain, addr, addr, e->prot,
PAGE_SIZE);
if (ret)
return ret;
/*
* if unity mapping is in aperture range mark the page
* as allocated in the aperture
*/
if (addr < dma_dom->aperture_size)
__set_bit(addr >> PAGE_SHIFT,
dma_dom->aperture[0]->bitmap);
}
return 0;
}
/*
* Init the unity mappings for a specific IOMMU in the system
*
* Basically iterates over all unity mapping entries and applies them to
* the default domain DMA of that IOMMU if necessary.
*/
static int iommu_init_unity_mappings(struct amd_iommu *iommu)
{
struct unity_map_entry *entry;
int ret;
list_for_each_entry(entry, &amd_iommu_unity_map, list) {
if (!iommu_for_unity_map(iommu, entry))
continue;
ret = dma_ops_unity_map(iommu->default_dom, entry);
if (ret)
return ret;
}
return 0;
}
/*
* Inits the unity mappings required for a specific device
*/
static int init_unity_mappings_for_device(struct dma_ops_domain *dma_dom,
u16 devid)
{
struct unity_map_entry *e;
int ret;
list_for_each_entry(e, &amd_iommu_unity_map, list) {
if (!(devid >= e->devid_start && devid <= e->devid_end))
continue;
ret = dma_ops_unity_map(dma_dom, e);
if (ret)
return ret;
}
return 0;
}
/****************************************************************************
*
* The next functions belong to the address allocator for the dma_ops
* interface functions. They work like the allocators in the other IOMMU
* drivers. Its basically a bitmap which marks the allocated pages in
* the aperture. Maybe it could be enhanced in the future to a more
* efficient allocator.
*
****************************************************************************/
/*
* The address allocator core functions.
*
* called with domain->lock held
*/
/*
* Used to reserve address ranges in the aperture (e.g. for exclusion
* ranges.
*/
static void dma_ops_reserve_addresses(struct dma_ops_domain *dom,
unsigned long start_page,
unsigned int pages)
{
unsigned int i, last_page = dom->aperture_size >> PAGE_SHIFT;
if (start_page + pages > last_page)
pages = last_page - start_page;
for (i = start_page; i < start_page + pages; ++i) {
int index = i / APERTURE_RANGE_PAGES;
int page = i % APERTURE_RANGE_PAGES;
__set_bit(page, dom->aperture[index]->bitmap);
}
}
/*
* This function is used to add a new aperture range to an existing
* aperture in case of dma_ops domain allocation or address allocation
* failure.
*/
static int alloc_new_range(struct dma_ops_domain *dma_dom,
bool populate, gfp_t gfp)
{
int index = dma_dom->aperture_size >> APERTURE_RANGE_SHIFT;
struct amd_iommu *iommu;
unsigned long i;
#ifdef CONFIG_IOMMU_STRESS
populate = false;
#endif
if (index >= APERTURE_MAX_RANGES)
return -ENOMEM;
dma_dom->aperture[index] = kzalloc(sizeof(struct aperture_range), gfp);
if (!dma_dom->aperture[index])
return -ENOMEM;
dma_dom->aperture[index]->bitmap = (void *)get_zeroed_page(gfp);
if (!dma_dom->aperture[index]->bitmap)
goto out_free;
dma_dom->aperture[index]->offset = dma_dom->aperture_size;
if (populate) {
unsigned long address = dma_dom->aperture_size;
int i, num_ptes = APERTURE_RANGE_PAGES / 512;
u64 *pte, *pte_page;
for (i = 0; i < num_ptes; ++i) {
pte = alloc_pte(&dma_dom->domain, address, PAGE_SIZE,
&pte_page, gfp);
if (!pte)
goto out_free;
dma_dom->aperture[index]->pte_pages[i] = pte_page;
address += APERTURE_RANGE_SIZE / 64;
}
}
dma_dom->aperture_size += APERTURE_RANGE_SIZE;
/* Intialize the exclusion range if necessary */
for_each_iommu(iommu) {
if (iommu->exclusion_start &&
iommu->exclusion_start >= dma_dom->aperture[index]->offset
&& iommu->exclusion_start < dma_dom->aperture_size) {
unsigned long startpage;
int pages = iommu_num_pages(iommu->exclusion_start,
iommu->exclusion_length,
PAGE_SIZE);
startpage = iommu->exclusion_start >> PAGE_SHIFT;
dma_ops_reserve_addresses(dma_dom, startpage, pages);
}
}
/*
* Check for areas already mapped as present in the new aperture
* range and mark those pages as reserved in the allocator. Such
* mappings may already exist as a result of requested unity
* mappings for devices.
*/
for (i = dma_dom->aperture[index]->offset;
i < dma_dom->aperture_size;
i += PAGE_SIZE) {
u64 *pte = fetch_pte(&dma_dom->domain, i);
if (!pte || !IOMMU_PTE_PRESENT(*pte))
continue;
dma_ops_reserve_addresses(dma_dom, i << PAGE_SHIFT, 1);
}
update_domain(&dma_dom->domain);
return 0;
out_free:
update_domain(&dma_dom->domain);
free_page((unsigned long)dma_dom->aperture[index]->bitmap);
kfree(dma_dom->aperture[index]);
dma_dom->aperture[index] = NULL;
return -ENOMEM;
}
static unsigned long dma_ops_area_alloc(struct device *dev,
struct dma_ops_domain *dom,
unsigned int pages,
unsigned long align_mask,
u64 dma_mask,
unsigned long start)
{
unsigned long next_bit = dom->next_address % APERTURE_RANGE_SIZE;
int max_index = dom->aperture_size >> APERTURE_RANGE_SHIFT;
int i = start >> APERTURE_RANGE_SHIFT;
unsigned long boundary_size;
unsigned long address = -1;
unsigned long limit;
next_bit >>= PAGE_SHIFT;
boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
PAGE_SIZE) >> PAGE_SHIFT;
for (;i < max_index; ++i) {
unsigned long offset = dom->aperture[i]->offset >> PAGE_SHIFT;
if (dom->aperture[i]->offset >= dma_mask)
break;
limit = iommu_device_max_index(APERTURE_RANGE_PAGES, offset,
dma_mask >> PAGE_SHIFT);
address = iommu_area_alloc(dom->aperture[i]->bitmap,
limit, next_bit, pages, 0,
boundary_size, align_mask);
if (address != -1) {
address = dom->aperture[i]->offset +
(address << PAGE_SHIFT);
dom->next_address = address + (pages << PAGE_SHIFT);
break;
}
next_bit = 0;
}
return address;
}
static unsigned long dma_ops_alloc_addresses(struct device *dev,
struct dma_ops_domain *dom,
unsigned int pages,
unsigned long align_mask,
u64 dma_mask)
{
unsigned long address;
#ifdef CONFIG_IOMMU_STRESS
dom->next_address = 0;
dom->need_flush = true;
#endif
address = dma_ops_area_alloc(dev, dom, pages, align_mask,
dma_mask, dom->next_address);
if (address == -1) {
dom->next_address = 0;
address = dma_ops_area_alloc(dev, dom, pages, align_mask,
dma_mask, 0);
dom->need_flush = true;
}
if (unlikely(address == -1))
address = DMA_ERROR_CODE;
WARN_ON((address + (PAGE_SIZE*pages)) > dom->aperture_size);
return address;
}
/*
* The address free function.
*
* called with domain->lock held
*/
static void dma_ops_free_addresses(struct dma_ops_domain *dom,
unsigned long address,
unsigned int pages)
{
unsigned i = address >> APERTURE_RANGE_SHIFT;
struct aperture_range *range = dom->aperture[i];
BUG_ON(i >= APERTURE_MAX_RANGES || range == NULL);
#ifdef CONFIG_IOMMU_STRESS
if (i < 4)
return;
#endif
if (address >= dom->next_address)
dom->need_flush = true;
address = (address % APERTURE_RANGE_SIZE) >> PAGE_SHIFT;
bitmap_clear(range->bitmap, address, pages);
}
/****************************************************************************
*
* The next functions belong to the domain allocation. A domain is
* allocated for every IOMMU as the default domain. If device isolation
* is enabled, every device get its own domain. The most important thing
* about domains is the page table mapping the DMA address space they
* contain.
*
****************************************************************************/
/*
* This function adds a protection domain to the global protection domain list
*/
static void add_domain_to_list(struct protection_domain *domain)
{
unsigned long flags;
spin_lock_irqsave(&amd_iommu_pd_lock, flags);
list_add(&domain->list, &amd_iommu_pd_list);
spin_unlock_irqrestore(&amd_iommu_pd_lock, flags);
}
/*
* This function removes a protection domain to the global
* protection domain list
*/
static void del_domain_from_list(struct protection_domain *domain)
{
unsigned long flags;
spin_lock_irqsave(&amd_iommu_pd_lock, flags);
list_del(&domain->list);
spin_unlock_irqrestore(&amd_iommu_pd_lock, flags);
}
static u16 domain_id_alloc(void)
{
unsigned long flags;
int id;
write_lock_irqsave(&amd_iommu_devtable_lock, flags);
id = find_first_zero_bit(amd_iommu_pd_alloc_bitmap, MAX_DOMAIN_ID);
BUG_ON(id == 0);
if (id > 0 && id < MAX_DOMAIN_ID)
__set_bit(id, amd_iommu_pd_alloc_bitmap);
else
id = 0;
write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
return id;
}
static void domain_id_free(int id)
{
unsigned long flags;
write_lock_irqsave(&amd_iommu_devtable_lock, flags);
if (id > 0 && id < MAX_DOMAIN_ID)
__clear_bit(id, amd_iommu_pd_alloc_bitmap);
write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
}
static void free_pagetable(struct protection_domain *domain)
{
int i, j;
u64 *p1, *p2, *p3;
p1 = domain->pt_root;
if (!p1)
return;
for (i = 0; i < 512; ++i) {
if (!IOMMU_PTE_PRESENT(p1[i]))
continue;
p2 = IOMMU_PTE_PAGE(p1[i]);
for (j = 0; j < 512; ++j) {
if (!IOMMU_PTE_PRESENT(p2[j]))
continue;
p3 = IOMMU_PTE_PAGE(p2[j]);
free_page((unsigned long)p3);
}
free_page((unsigned long)p2);
}
free_page((unsigned long)p1);
domain->pt_root = NULL;
}
/*
* Free a domain, only used if something went wrong in the
* allocation path and we need to free an already allocated page table
*/
static void dma_ops_domain_free(struct dma_ops_domain *dom)
{
int i;
if (!dom)
return;
del_domain_from_list(&dom->domain);
free_pagetable(&dom->domain);
for (i = 0; i < APERTURE_MAX_RANGES; ++i) {
if (!dom->aperture[i])
continue;
free_page((unsigned long)dom->aperture[i]->bitmap);
kfree(dom->aperture[i]);
}
kfree(dom);
}
/*
* Allocates a new protection domain usable for the dma_ops functions.
* It also intializes the page table and the address allocator data
* structures required for the dma_ops interface
*/
static struct dma_ops_domain *dma_ops_domain_alloc(void)
{
struct dma_ops_domain *dma_dom;
dma_dom = kzalloc(sizeof(struct dma_ops_domain), GFP_KERNEL);
if (!dma_dom)
return NULL;
spin_lock_init(&dma_dom->domain.lock);
dma_dom->domain.id = domain_id_alloc();
if (dma_dom->domain.id == 0)
goto free_dma_dom;
INIT_LIST_HEAD(&dma_dom->domain.dev_list);
dma_dom->domain.mode = PAGE_MODE_2_LEVEL;
dma_dom->domain.pt_root = (void *)get_zeroed_page(GFP_KERNEL);
dma_dom->domain.flags = PD_DMA_OPS_MASK;
dma_dom->domain.priv = dma_dom;
if (!dma_dom->domain.pt_root)
goto free_dma_dom;
dma_dom->need_flush = false;
dma_dom->target_dev = 0xffff;
add_domain_to_list(&dma_dom->domain);
if (alloc_new_range(dma_dom, true, GFP_KERNEL))
goto free_dma_dom;
/*
* mark the first page as allocated so we never return 0 as
* a valid dma-address. So we can use 0 as error value
*/
dma_dom->aperture[0]->bitmap[0] = 1;
dma_dom->next_address = 0;
return dma_dom;
free_dma_dom:
dma_ops_domain_free(dma_dom);
return NULL;
}
/*
* little helper function to check whether a given protection domain is a
* dma_ops domain
*/
static bool dma_ops_domain(struct protection_domain *domain)
{
return domain->flags & PD_DMA_OPS_MASK;
}
static void set_dte_entry(u16 devid, struct protection_domain *domain)
{
u64 pte_root = virt_to_phys(domain->pt_root);
pte_root |= (domain->mode & DEV_ENTRY_MODE_MASK)
<< DEV_ENTRY_MODE_SHIFT;
pte_root |= IOMMU_PTE_IR | IOMMU_PTE_IW | IOMMU_PTE_P | IOMMU_PTE_TV;
amd_iommu_dev_table[devid].data[2] = domain->id;
amd_iommu_dev_table[devid].data[1] = upper_32_bits(pte_root);
amd_iommu_dev_table[devid].data[0] = lower_32_bits(pte_root);
}
static void clear_dte_entry(u16 devid)
{
/* remove entry from the device table seen by the hardware */
amd_iommu_dev_table[devid].data[0] = IOMMU_PTE_P | IOMMU_PTE_TV;
amd_iommu_dev_table[devid].data[1] = 0;
amd_iommu_dev_table[devid].data[2] = 0;
amd_iommu_apply_erratum_63(devid);
}
static void do_attach(struct device *dev, struct protection_domain *domain)
{
struct iommu_dev_data *dev_data;
struct amd_iommu *iommu;
u16 devid;
devid = get_device_id(dev);
iommu = amd_iommu_rlookup_table[devid];
dev_data = get_dev_data(dev);
/* Update data structures */
dev_data->domain = domain;
list_add(&dev_data->list, &domain->dev_list);
set_dte_entry(devid, domain);
/* Do reference counting */
domain->dev_iommu[iommu->index] += 1;
domain->dev_cnt += 1;
/* Flush the DTE entry */
iommu_flush_device(dev);
}
static void do_detach(struct device *dev)
{
struct iommu_dev_data *dev_data;
struct amd_iommu *iommu;
u16 devid;
devid = get_device_id(dev);
iommu = amd_iommu_rlookup_table[devid];
dev_data = get_dev_data(dev);
/* decrease reference counters */
dev_data->domain->dev_iommu[iommu->index] -= 1;
dev_data->domain->dev_cnt -= 1;
/* Update data structures */
dev_data->domain = NULL;
list_del(&dev_data->list);
clear_dte_entry(devid);
/* Flush the DTE entry */
iommu_flush_device(dev);
}
/*
* If a device is not yet associated with a domain, this function does
* assigns it visible for the hardware
*/
static int __attach_device(struct device *dev,
struct protection_domain *domain)
{
struct iommu_dev_data *dev_data, *alias_data;
int ret;
dev_data = get_dev_data(dev);
alias_data = get_dev_data(dev_data->alias);
if (!alias_data)
return -EINVAL;
/* lock domain */
spin_lock(&domain->lock);
/* Some sanity checks */
ret = -EBUSY;
if (alias_data->domain != NULL &&
alias_data->domain != domain)
goto out_unlock;
if (dev_data->domain != NULL &&
dev_data->domain != domain)
goto out_unlock;
/* Do real assignment */
if (dev_data->alias != dev) {
alias_data = get_dev_data(dev_data->alias);
if (alias_data->domain == NULL)
do_attach(dev_data->alias, domain);
atomic_inc(&alias_data->bind);
}
if (dev_data->domain == NULL)
do_attach(dev, domain);
atomic_inc(&dev_data->bind);
ret = 0;
out_unlock:
/* ready */
spin_unlock(&domain->lock);
return ret;
}
/*
* If a device is not yet associated with a domain, this function does
* assigns it visible for the hardware
*/
static int attach_device(struct device *dev,
struct protection_domain *domain)
{
unsigned long flags;
int ret;
write_lock_irqsave(&amd_iommu_devtable_lock, flags);
ret = __attach_device(dev, domain);
write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
/*
* We might boot into a crash-kernel here. The crashed kernel
* left the caches in the IOMMU dirty. So we have to flush
* here to evict all dirty stuff.
*/
iommu_flush_tlb_pde(domain);
return ret;
}
/*
* Removes a device from a protection domain (unlocked)
*/
static void __detach_device(struct device *dev)
{
struct iommu_dev_data *dev_data = get_dev_data(dev);
struct iommu_dev_data *alias_data;
struct protection_domain *domain;
unsigned long flags;
BUG_ON(!dev_data->domain);
domain = dev_data->domain;
spin_lock_irqsave(&domain->lock, flags);
if (dev_data->alias != dev) {
alias_data = get_dev_data(dev_data->alias);
if (atomic_dec_and_test(&alias_data->bind))
do_detach(dev_data->alias);
}
if (atomic_dec_and_test(&dev_data->bind))
do_detach(dev);
spin_unlock_irqrestore(&domain->lock, flags);
/*
* If we run in passthrough mode the device must be assigned to the
* passthrough domain if it is detached from any other domain.
* Make sure we can deassign from the pt_domain itself.
*/
if (iommu_pass_through &&
(dev_data->domain == NULL && domain != pt_domain))
__attach_device(dev, pt_domain);
}
/*
* Removes a device from a protection domain (with devtable_lock held)
*/
static void detach_device(struct device *dev)
{
unsigned long flags;
/* lock device table */
write_lock_irqsave(&amd_iommu_devtable_lock, flags);
__detach_device(dev);
write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
}
/*
* Find out the protection domain structure for a given PCI device. This
* will give us the pointer to the page table root for example.
*/
static struct protection_domain *domain_for_device(struct device *dev)
{
struct protection_domain *dom;
struct iommu_dev_data *dev_data, *alias_data;
unsigned long flags;
u16 devid, alias;
devid = get_device_id(dev);
alias = amd_iommu_alias_table[devid];
dev_data = get_dev_data(dev);
alias_data = get_dev_data(dev_data->alias);
if (!alias_data)
return NULL;
read_lock_irqsave(&amd_iommu_devtable_lock, flags);
dom = dev_data->domain;
if (dom == NULL &&
alias_data->domain != NULL) {
__attach_device(dev, alias_data->domain);
dom = alias_data->domain;
}
read_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
return dom;
}
static int device_change_notifier(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
u16 devid;
struct protection_domain *domain;
struct dma_ops_domain *dma_domain;
struct amd_iommu *iommu;
unsigned long flags;
if (!check_device(dev))
return 0;
devid = get_device_id(dev);
iommu = amd_iommu_rlookup_table[devid];
switch (action) {
case BUS_NOTIFY_UNBOUND_DRIVER:
domain = domain_for_device(dev);
if (!domain)
goto out;
if (iommu_pass_through)
break;
detach_device(dev);
break;
case BUS_NOTIFY_ADD_DEVICE:
iommu_init_device(dev);
domain = domain_for_device(dev);
/* allocate a protection domain if a device is added */
dma_domain = find_protection_domain(devid);
if (dma_domain)
goto out;
dma_domain = dma_ops_domain_alloc();
if (!dma_domain)
goto out;
dma_domain->target_dev = devid;
spin_lock_irqsave(&iommu_pd_list_lock, flags);
list_add_tail(&dma_domain->list, &iommu_pd_list);
spin_unlock_irqrestore(&iommu_pd_list_lock, flags);
break;
case BUS_NOTIFY_DEL_DEVICE:
iommu_uninit_device(dev);
default:
goto out;
}
iommu_flush_device(dev);
iommu_completion_wait(iommu);
out:
return 0;
}
static struct notifier_block device_nb = {
.notifier_call = device_change_notifier,
};
void amd_iommu_init_notifier(void)
{
bus_register_notifier(&pci_bus_type, &device_nb);
}
/*****************************************************************************
*
* The next functions belong to the dma_ops mapping/unmapping code.
*
*****************************************************************************/
/*
* In the dma_ops path we only have the struct device. This function
* finds the corresponding IOMMU, the protection domain and the
* requestor id for a given device.
* If the device is not yet associated with a domain this is also done
* in this function.
*/
static struct protection_domain *get_domain(struct device *dev)
{
struct protection_domain *domain;
struct dma_ops_domain *dma_dom;
u16 devid = get_device_id(dev);
if (!check_device(dev))
return ERR_PTR(-EINVAL);
domain = domain_for_device(dev);
if (domain != NULL && !dma_ops_domain(domain))
return ERR_PTR(-EBUSY);
if (domain != NULL)
return domain;
/* Device not bount yet - bind it */
dma_dom = find_protection_domain(devid);
if (!dma_dom)
dma_dom = amd_iommu_rlookup_table[devid]->default_dom;
attach_device(dev, &dma_dom->domain);
DUMP_printk("Using protection domain %d for device %s\n",
dma_dom->domain.id, dev_name(dev));
return &dma_dom->domain;
}
static void update_device_table(struct protection_domain *domain)
{
struct iommu_dev_data *dev_data;
list_for_each_entry(dev_data, &domain->dev_list, list) {
u16 devid = get_device_id(dev_data->dev);
set_dte_entry(devid, domain);
}
}
static void update_domain(struct protection_domain *domain)
{
if (!domain->updated)
return;
update_device_table(domain);
iommu_flush_domain_devices(domain);
iommu_flush_tlb_pde(domain);
domain->updated = false;
}
/*
* This function fetches the PTE for a given address in the aperture
*/
static u64* dma_ops_get_pte(struct dma_ops_domain *dom,
unsigned long address)
{
struct aperture_range *aperture;
u64 *pte, *pte_page;
aperture = dom->aperture[APERTURE_RANGE_INDEX(address)];
if (!aperture)
return NULL;
pte = aperture->pte_pages[APERTURE_PAGE_INDEX(address)];
if (!pte) {
pte = alloc_pte(&dom->domain, address, PAGE_SIZE, &pte_page,
GFP_ATOMIC);
aperture->pte_pages[APERTURE_PAGE_INDEX(address)] = pte_page;
} else
pte += PM_LEVEL_INDEX(0, address);
update_domain(&dom->domain);
return pte;
}
/*
* This is the generic map function. It maps one 4kb page at paddr to
* the given address in the DMA address space for the domain.
*/
static dma_addr_t dma_ops_domain_map(struct dma_ops_domain *dom,
unsigned long address,
phys_addr_t paddr,
int direction)
{
u64 *pte, __pte;
WARN_ON(address > dom->aperture_size);
paddr &= PAGE_MASK;
pte = dma_ops_get_pte(dom, address);
if (!pte)
return DMA_ERROR_CODE;
__pte = paddr | IOMMU_PTE_P | IOMMU_PTE_FC;
if (direction == DMA_TO_DEVICE)
__pte |= IOMMU_PTE_IR;
else if (direction == DMA_FROM_DEVICE)
__pte |= IOMMU_PTE_IW;
else if (direction == DMA_BIDIRECTIONAL)
__pte |= IOMMU_PTE_IR | IOMMU_PTE_IW;
WARN_ON(*pte);
*pte = __pte;
return (dma_addr_t)address;
}
/*
* The generic unmapping function for on page in the DMA address space.
*/
static void dma_ops_domain_unmap(struct dma_ops_domain *dom,
unsigned long address)
{
struct aperture_range *aperture;
u64 *pte;
if (address >= dom->aperture_size)
return;
aperture = dom->aperture[APERTURE_RANGE_INDEX(address)];
if (!aperture)
return;
pte = aperture->pte_pages[APERTURE_PAGE_INDEX(address)];
if (!pte)
return;
pte += PM_LEVEL_INDEX(0, address);
WARN_ON(!*pte);
*pte = 0ULL;
}
/*
* This function contains common code for mapping of a physically
* contiguous memory region into DMA address space. It is used by all
* mapping functions provided with this IOMMU driver.
* Must be called with the domain lock held.
*/
static dma_addr_t __map_single(struct device *dev,
struct dma_ops_domain *dma_dom,
phys_addr_t paddr,
size_t size,
int dir,
bool align,
u64 dma_mask)
{
dma_addr_t offset = paddr & ~PAGE_MASK;
dma_addr_t address, start, ret;
unsigned int pages;
unsigned long align_mask = 0;
int i;
pages = iommu_num_pages(paddr, size, PAGE_SIZE);
paddr &= PAGE_MASK;
INC_STATS_COUNTER(total_map_requests);
if (pages > 1)
INC_STATS_COUNTER(cross_page);
if (align)
align_mask = (1UL << get_order(size)) - 1;
retry:
address = dma_ops_alloc_addresses(dev, dma_dom, pages, align_mask,
dma_mask);
if (unlikely(address == DMA_ERROR_CODE)) {
/*
* setting next_address here will let the address
* allocator only scan the new allocated range in the
* first run. This is a small optimization.
*/
dma_dom->next_address = dma_dom->aperture_size;
if (alloc_new_range(dma_dom, false, GFP_ATOMIC))
goto out;
/*
* aperture was successfully enlarged by 128 MB, try
* allocation again
*/
goto retry;
}
start = address;
for (i = 0; i < pages; ++i) {
ret = dma_ops_domain_map(dma_dom, start, paddr, dir);
if (ret == DMA_ERROR_CODE)
goto out_unmap;
paddr += PAGE_SIZE;
start += PAGE_SIZE;
}
address += offset;
ADD_STATS_COUNTER(alloced_io_mem, size);
if (unlikely(dma_dom->need_flush && !amd_iommu_unmap_flush)) {
iommu_flush_tlb(&dma_dom->domain);
dma_dom->need_flush = false;
} else if (unlikely(amd_iommu_np_cache))
iommu_flush_pages(&dma_dom->domain, address, size);
out:
return address;
out_unmap:
for (--i; i >= 0; --i) {
start -= PAGE_SIZE;
dma_ops_domain_unmap(dma_dom, start);
}
dma_ops_free_addresses(dma_dom, address, pages);
return DMA_ERROR_CODE;
}
/*
* Does the reverse of the __map_single function. Must be called with
* the domain lock held too
*/
static void __unmap_single(struct dma_ops_domain *dma_dom,
dma_addr_t dma_addr,
size_t size,
int dir)
{
dma_addr_t i, start;
unsigned int pages;
if ((dma_addr == DMA_ERROR_CODE) ||
(dma_addr + size > dma_dom->aperture_size))
return;
pages = iommu_num_pages(dma_addr, size, PAGE_SIZE);
dma_addr &= PAGE_MASK;
start = dma_addr;
for (i = 0; i < pages; ++i) {
dma_ops_domain_unmap(dma_dom, start);
start += PAGE_SIZE;
}
SUB_STATS_COUNTER(alloced_io_mem, size);
dma_ops_free_addresses(dma_dom, dma_addr, pages);
if (amd_iommu_unmap_flush || dma_dom->need_flush) {
iommu_flush_pages(&dma_dom->domain, dma_addr, size);
dma_dom->need_flush = false;
}
}
/*
* The exported map_single function for dma_ops.
*/
static dma_addr_t map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction dir,
struct dma_attrs *attrs)
{
unsigned long flags;
struct protection_domain *domain;
dma_addr_t addr;
u64 dma_mask;
phys_addr_t paddr = page_to_phys(page) + offset;
INC_STATS_COUNTER(cnt_map_single);
domain = get_domain(dev);
if (PTR_ERR(domain) == -EINVAL)
return (dma_addr_t)paddr;
else if (IS_ERR(domain))
return DMA_ERROR_CODE;
dma_mask = *dev->dma_mask;
spin_lock_irqsave(&domain->lock, flags);
addr = __map_single(dev, domain->priv, paddr, size, dir, false,
dma_mask);
if (addr == DMA_ERROR_CODE)
goto out;
iommu_flush_complete(domain);
out:
spin_unlock_irqrestore(&domain->lock, flags);
return addr;
}
/*
* The exported unmap_single function for dma_ops.
*/
static void unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
enum dma_data_direction dir, struct dma_attrs *attrs)
{
unsigned long flags;
struct protection_domain *domain;
INC_STATS_COUNTER(cnt_unmap_single);
domain = get_domain(dev);
if (IS_ERR(domain))
return;
spin_lock_irqsave(&domain->lock, flags);
__unmap_single(domain->priv, dma_addr, size, dir);
iommu_flush_complete(domain);
spin_unlock_irqrestore(&domain->lock, flags);
}
/*
* This is a special map_sg function which is used if we should map a
* device which is not handled by an AMD IOMMU in the system.
*/
static int map_sg_no_iommu(struct device *dev, struct scatterlist *sglist,
int nelems, int dir)
{
struct scatterlist *s;
int i;
for_each_sg(sglist, s, nelems, i) {
s->dma_address = (dma_addr_t)sg_phys(s);
s->dma_length = s->length;
}
return nelems;
}
/*
* The exported map_sg function for dma_ops (handles scatter-gather
* lists).
*/
static int map_sg(struct device *dev, struct scatterlist *sglist,
int nelems, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
unsigned long flags;
struct protection_domain *domain;
int i;
struct scatterlist *s;
phys_addr_t paddr;
int mapped_elems = 0;
u64 dma_mask;
INC_STATS_COUNTER(cnt_map_sg);
domain = get_domain(dev);
if (PTR_ERR(domain) == -EINVAL)
return map_sg_no_iommu(dev, sglist, nelems, dir);
else if (IS_ERR(domain))
return 0;
dma_mask = *dev->dma_mask;
spin_lock_irqsave(&domain->lock, flags);
for_each_sg(sglist, s, nelems, i) {
paddr = sg_phys(s);
s->dma_address = __map_single(dev, domain->priv,
paddr, s->length, dir, false,
dma_mask);
if (s->dma_address) {
s->dma_length = s->length;
mapped_elems++;
} else
goto unmap;
}
iommu_flush_complete(domain);
out:
spin_unlock_irqrestore(&domain->lock, flags);
return mapped_elems;
unmap:
for_each_sg(sglist, s, mapped_elems, i) {
if (s->dma_address)
__unmap_single(domain->priv, s->dma_address,
s->dma_length, dir);
s->dma_address = s->dma_length = 0;
}
mapped_elems = 0;
goto out;
}
/*
* The exported map_sg function for dma_ops (handles scatter-gather
* lists).
*/
static void unmap_sg(struct device *dev, struct scatterlist *sglist,
int nelems, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
unsigned long flags;
struct protection_domain *domain;
struct scatterlist *s;
int i;
INC_STATS_COUNTER(cnt_unmap_sg);
domain = get_domain(dev);
if (IS_ERR(domain))
return;
spin_lock_irqsave(&domain->lock, flags);
for_each_sg(sglist, s, nelems, i) {
__unmap_single(domain->priv, s->dma_address,
s->dma_length, dir);
s->dma_address = s->dma_length = 0;
}
iommu_flush_complete(domain);
spin_unlock_irqrestore(&domain->lock, flags);
}
/*
* The exported alloc_coherent function for dma_ops.
*/
static void *alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_addr, gfp_t flag)
{
unsigned long flags;
void *virt_addr;
struct protection_domain *domain;
phys_addr_t paddr;
u64 dma_mask = dev->coherent_dma_mask;
INC_STATS_COUNTER(cnt_alloc_coherent);
domain = get_domain(dev);
if (PTR_ERR(domain) == -EINVAL) {
virt_addr = (void *)__get_free_pages(flag, get_order(size));
*dma_addr = __pa(virt_addr);
return virt_addr;
} else if (IS_ERR(domain))
return NULL;
dma_mask = dev->coherent_dma_mask;
flag &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
flag |= __GFP_ZERO;
virt_addr = (void *)__get_free_pages(flag, get_order(size));
if (!virt_addr)
return NULL;
paddr = virt_to_phys(virt_addr);
if (!dma_mask)
dma_mask = *dev->dma_mask;
spin_lock_irqsave(&domain->lock, flags);
*dma_addr = __map_single(dev, domain->priv, paddr,
size, DMA_BIDIRECTIONAL, true, dma_mask);
if (*dma_addr == DMA_ERROR_CODE) {
spin_unlock_irqrestore(&domain->lock, flags);
goto out_free;
}
iommu_flush_complete(domain);
spin_unlock_irqrestore(&domain->lock, flags);
return virt_addr;
out_free:
free_pages((unsigned long)virt_addr, get_order(size));
return NULL;
}
/*
* The exported free_coherent function for dma_ops.
*/
static void free_coherent(struct device *dev, size_t size,
void *virt_addr, dma_addr_t dma_addr)
{
unsigned long flags;
struct protection_domain *domain;
INC_STATS_COUNTER(cnt_free_coherent);
domain = get_domain(dev);
if (IS_ERR(domain))
goto free_mem;
spin_lock_irqsave(&domain->lock, flags);
__unmap_single(domain->priv, dma_addr, size, DMA_BIDIRECTIONAL);
iommu_flush_complete(domain);
spin_unlock_irqrestore(&domain->lock, flags);
free_mem:
free_pages((unsigned long)virt_addr, get_order(size));
}
/*
* This function is called by the DMA layer to find out if we can handle a
* particular device. It is part of the dma_ops.
*/
static int amd_iommu_dma_supported(struct device *dev, u64 mask)
{
return check_device(dev);
}
/*
* The function for pre-allocating protection domains.
*
* If the driver core informs the DMA layer if a driver grabs a device
* we don't need to preallocate the protection domains anymore.
* For now we have to.
*/
static void prealloc_protection_domains(void)
{
struct pci_dev *dev = NULL;
struct dma_ops_domain *dma_dom;
u16 devid;
for_each_pci_dev(dev) {
/* Do we handle this device? */
if (!check_device(&dev->dev))
continue;
/* Is there already any domain for it? */
if (domain_for_device(&dev->dev))
continue;
devid = get_device_id(&dev->dev);
dma_dom = dma_ops_domain_alloc();
if (!dma_dom)
continue;
init_unity_mappings_for_device(dma_dom, devid);
dma_dom->target_dev = devid;
attach_device(&dev->dev, &dma_dom->domain);
list_add_tail(&dma_dom->list, &iommu_pd_list);
}
}
static struct dma_map_ops amd_iommu_dma_ops = {
.alloc_coherent = alloc_coherent,
.free_coherent = free_coherent,
.map_page = map_page,
.unmap_page = unmap_page,
.map_sg = map_sg,
.unmap_sg = unmap_sg,
.dma_supported = amd_iommu_dma_supported,
};
/*
* The function which clues the AMD IOMMU driver into dma_ops.
*/
void __init amd_iommu_init_api(void)
{
register_iommu(&amd_iommu_ops);
}
int __init amd_iommu_init_dma_ops(void)
{
struct amd_iommu *iommu;
int ret;
/*
* first allocate a default protection domain for every IOMMU we
* found in the system. Devices not assigned to any other
* protection domain will be assigned to the default one.
*/
for_each_iommu(iommu) {
iommu->default_dom = dma_ops_domain_alloc();
if (iommu->default_dom == NULL)
return -ENOMEM;
iommu->default_dom->domain.flags |= PD_DEFAULT_MASK;
ret = iommu_init_unity_mappings(iommu);
if (ret)
goto free_domains;
}
/*
* Pre-allocate the protection domains for each device.
*/
prealloc_protection_domains();
iommu_detected = 1;
swiotlb = 0;
/* Make the driver finally visible to the drivers */
dma_ops = &amd_iommu_dma_ops;
amd_iommu_stats_init();
return 0;
free_domains:
for_each_iommu(iommu) {
if (iommu->default_dom)
dma_ops_domain_free(iommu->default_dom);
}
return ret;
}
/*****************************************************************************
*
* The following functions belong to the exported interface of AMD IOMMU
*
* This interface allows access to lower level functions of the IOMMU
* like protection domain handling and assignement of devices to domains
* which is not possible with the dma_ops interface.
*
*****************************************************************************/
static void cleanup_domain(struct protection_domain *domain)
{
struct iommu_dev_data *dev_data, *next;
unsigned long flags;
write_lock_irqsave(&amd_iommu_devtable_lock, flags);
list_for_each_entry_safe(dev_data, next, &domain->dev_list, list) {
struct device *dev = dev_data->dev;
__detach_device(dev);
atomic_set(&dev_data->bind, 0);
}
write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
}
static void protection_domain_free(struct protection_domain *domain)
{
if (!domain)
return;
del_domain_from_list(domain);
if (domain->id)
domain_id_free(domain->id);
kfree(domain);
}
static struct protection_domain *protection_domain_alloc(void)
{
struct protection_domain *domain;
domain = kzalloc(sizeof(*domain), GFP_KERNEL);
if (!domain)
return NULL;
spin_lock_init(&domain->lock);
mutex_init(&domain->api_lock);
domain->id = domain_id_alloc();
if (!domain->id)
goto out_err;
INIT_LIST_HEAD(&domain->dev_list);
add_domain_to_list(domain);
return domain;
out_err:
kfree(domain);
return NULL;
}
static int amd_iommu_domain_init(struct iommu_domain *dom)
{
struct protection_domain *domain;
domain = protection_domain_alloc();
if (!domain)
goto out_free;
domain->mode = PAGE_MODE_3_LEVEL;
domain->pt_root = (void *)get_zeroed_page(GFP_KERNEL);
if (!domain->pt_root)
goto out_free;
dom->priv = domain;
return 0;
out_free:
protection_domain_free(domain);
return -ENOMEM;
}
static void amd_iommu_domain_destroy(struct iommu_domain *dom)
{
struct protection_domain *domain = dom->priv;
if (!domain)
return;
if (domain->dev_cnt > 0)
cleanup_domain(domain);
BUG_ON(domain->dev_cnt != 0);
free_pagetable(domain);
protection_domain_free(domain);
dom->priv = NULL;
}
static void amd_iommu_detach_device(struct iommu_domain *dom,
struct device *dev)
{
struct iommu_dev_data *dev_data = dev->archdata.iommu;
struct amd_iommu *iommu;
u16 devid;
if (!check_device(dev))
return;
devid = get_device_id(dev);
if (dev_data->domain != NULL)
detach_device(dev);
iommu = amd_iommu_rlookup_table[devid];
if (!iommu)
return;
iommu_flush_device(dev);
iommu_completion_wait(iommu);
}
static int amd_iommu_attach_device(struct iommu_domain *dom,
struct device *dev)
{
struct protection_domain *domain = dom->priv;
struct iommu_dev_data *dev_data;
struct amd_iommu *iommu;
int ret;
u16 devid;
if (!check_device(dev))
return -EINVAL;
dev_data = dev->archdata.iommu;
devid = get_device_id(dev);
iommu = amd_iommu_rlookup_table[devid];
if (!iommu)
return -EINVAL;
if (dev_data->domain)
detach_device(dev);
ret = attach_device(dev, domain);
iommu_completion_wait(iommu);
return ret;
}
static int amd_iommu_map(struct iommu_domain *dom, unsigned long iova,
phys_addr_t paddr, int gfp_order, int iommu_prot)
{
unsigned long page_size = 0x1000UL << gfp_order;
struct protection_domain *domain = dom->priv;
int prot = 0;
int ret;
if (iommu_prot & IOMMU_READ)
prot |= IOMMU_PROT_IR;
if (iommu_prot & IOMMU_WRITE)
prot |= IOMMU_PROT_IW;
mutex_lock(&domain->api_lock);
ret = iommu_map_page(domain, iova, paddr, prot, page_size);
mutex_unlock(&domain->api_lock);
return ret;
}
static int amd_iommu_unmap(struct iommu_domain *dom, unsigned long iova,
int gfp_order)
{
struct protection_domain *domain = dom->priv;
unsigned long page_size, unmap_size;
page_size = 0x1000UL << gfp_order;
mutex_lock(&domain->api_lock);
unmap_size = iommu_unmap_page(domain, iova, page_size);
mutex_unlock(&domain->api_lock);
iommu_flush_tlb_pde(domain);
return get_order(unmap_size);
}
static phys_addr_t amd_iommu_iova_to_phys(struct iommu_domain *dom,
unsigned long iova)
{
struct protection_domain *domain = dom->priv;
unsigned long offset_mask;
phys_addr_t paddr;
u64 *pte, __pte;
pte = fetch_pte(domain, iova);
if (!pte || !IOMMU_PTE_PRESENT(*pte))
return 0;
if (PM_PTE_LEVEL(*pte) == 0)
offset_mask = PAGE_SIZE - 1;
else
offset_mask = PTE_PAGE_SIZE(*pte) - 1;
__pte = *pte & PM_ADDR_MASK;
paddr = (__pte & ~offset_mask) | (iova & offset_mask);
return paddr;
}
static int amd_iommu_domain_has_cap(struct iommu_domain *domain,
unsigned long cap)
{
return 0;
}
static struct iommu_ops amd_iommu_ops = {
.domain_init = amd_iommu_domain_init,
.domain_destroy = amd_iommu_domain_destroy,
.attach_dev = amd_iommu_attach_device,
.detach_dev = amd_iommu_detach_device,
.map = amd_iommu_map,
.unmap = amd_iommu_unmap,
.iova_to_phys = amd_iommu_iova_to_phys,
.domain_has_cap = amd_iommu_domain_has_cap,
};
/*****************************************************************************
*
* The next functions do a basic initialization of IOMMU for pass through
* mode
*
* In passthrough mode the IOMMU is initialized and enabled but not used for
* DMA-API translation.
*
*****************************************************************************/
int __init amd_iommu_init_passthrough(void)
{
struct amd_iommu *iommu;
struct pci_dev *dev = NULL;
u16 devid;
/* allocate passthrough domain */
pt_domain = protection_domain_alloc();
if (!pt_domain)
return -ENOMEM;
pt_domain->mode |= PAGE_MODE_NONE;
while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
if (!check_device(&dev->dev))
continue;
devid = get_device_id(&dev->dev);
iommu = amd_iommu_rlookup_table[devid];
if (!iommu)
continue;
attach_device(&dev->dev, pt_domain);
}
pr_info("AMD-Vi: Initialized for Passthrough Mode\n");
return 0;
}
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