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Merge branch 'for-4.18/dax' into libnvdimm-for-next

This commit is contained in:
Dan Williams 2018-06-08 15:16:40 -07:00
parent 808c340be1 cc4a90ac81
commit b56845794e
21 changed files with 546 additions and 296 deletions
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14
drivers/dax/super.c
View File

@ -86,6 +86,7 @@ int __bdev_dax_supported(struct super_block *sb, int blocksize)
{
struct block_device *bdev = sb->s_bdev;
struct dax_device *dax_dev;
bool dax_enabled = false;
pgoff_t pgoff;
int err, id;
void *kaddr;
@ -134,14 +135,21 @@ int __bdev_dax_supported(struct super_block *sb, int blocksize)
* on being able to do (page_address(pfn_to_page())).
*/
WARN_ON(IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API));
dax_enabled = true;
} else if (pfn_t_devmap(pfn)) {
/* pass */;
} else {
struct dev_pagemap *pgmap;
pgmap = get_dev_pagemap(pfn_t_to_pfn(pfn), NULL);
if (pgmap && pgmap->type == MEMORY_DEVICE_FS_DAX)
dax_enabled = true;
put_dev_pagemap(pgmap);
}
if (!dax_enabled) {
pr_debug("VFS (%s): error: dax support not enabled\n",
sb->s_id);
return -EOPNOTSUPP;
}
return 0;
}
EXPORT_SYMBOL_GPL(__bdev_dax_supported);

2
drivers/nvdimm/pfn_devs.c
View File

@ -561,8 +561,6 @@ static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap)
res->start += start_pad;
res->end -= end_trunc;
pgmap->type = MEMORY_DEVICE_HOST;
if (nd_pfn->mode == PFN_MODE_RAM) {
if (offset < SZ_8K)
return -EINVAL;

25
drivers/nvdimm/pmem.c
View File

@ -289,6 +289,27 @@ static void pmem_release_disk(void *__pmem)
put_disk(pmem->disk);
}
static void pmem_release_pgmap_ops(void *__pgmap)
{
dev_pagemap_put_ops();
}
static void fsdax_pagefree(struct page *page, void *data)
{
wake_up_var(&page->_refcount);
}
static int setup_pagemap_fsdax(struct device *dev, struct dev_pagemap *pgmap)
{
dev_pagemap_get_ops();
if (devm_add_action_or_reset(dev, pmem_release_pgmap_ops, pgmap))
return -ENOMEM;
pgmap->type = MEMORY_DEVICE_FS_DAX;
pgmap->page_free = fsdax_pagefree;
return 0;
}
static int pmem_attach_disk(struct device *dev,
struct nd_namespace_common *ndns)
{
@ -347,6 +368,8 @@ static int pmem_attach_disk(struct device *dev,
pmem->pfn_flags = PFN_DEV;
pmem->pgmap.ref = &q->q_usage_counter;
if (is_nd_pfn(dev)) {
if (setup_pagemap_fsdax(dev, &pmem->pgmap))
return -ENOMEM;
addr = devm_memremap_pages(dev, &pmem->pgmap);
pfn_sb = nd_pfn->pfn_sb;
pmem->data_offset = le64_to_cpu(pfn_sb->dataoff);
@ -358,6 +381,8 @@ static int pmem_attach_disk(struct device *dev,
} else if (pmem_should_map_pages(dev)) {
memcpy(&pmem->pgmap.res, &nsio->res, sizeof(pmem->pgmap.res));
pmem->pgmap.altmap_valid = false;
if (setup_pagemap_fsdax(dev, &pmem->pgmap))
return -ENOMEM;
addr = devm_memremap_pages(dev, &pmem->pgmap);
pmem->pfn_flags |= PFN_MAP;
memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res));

1
fs/Kconfig
View File

@ -38,6 +38,7 @@ config FS_DAX
bool "Direct Access (DAX) support"
depends on MMU
depends on !(ARM || MIPS || SPARC)
select DEV_PAGEMAP_OPS if (ZONE_DEVICE && !FS_DAX_LIMITED)
select FS_IOMAP
select DAX
help

115
fs/dax.c
View File

@ -351,6 +351,19 @@ static void dax_disassociate_entry(void *entry, struct address_space *mapping,
}
}
static struct page *dax_busy_page(void *entry)
{
unsigned long pfn;
for_each_mapped_pfn(entry, pfn) {
struct page *page = pfn_to_page(pfn);
if (page_ref_count(page) > 1)
return page;
}
return NULL;
}
/*
* Find radix tree entry at given index. If it points to an exceptional entry,
* return it with the radix tree entry locked. If the radix tree doesn't
@ -492,6 +505,90 @@ static void *grab_mapping_entry(struct address_space *mapping, pgoff_t index,
return entry;
}
/**
* dax_layout_busy_page - find first pinned page in @mapping
* @mapping: address space to scan for a page with ref count > 1
*
* DAX requires ZONE_DEVICE mapped pages. These pages are never
* 'onlined' to the page allocator so they are considered idle when
* page->count == 1. A filesystem uses this interface to determine if
* any page in the mapping is busy, i.e. for DMA, or other
* get_user_pages() usages.
*
* It is expected that the filesystem is holding locks to block the
* establishment of new mappings in this address_space. I.e. it expects
* to be able to run unmap_mapping_range() and subsequently not race
* mapping_mapped() becoming true.
*/
struct page *dax_layout_busy_page(struct address_space *mapping)
{
pgoff_t indices[PAGEVEC_SIZE];
struct page *page = NULL;
struct pagevec pvec;
pgoff_t index, end;
unsigned i;
/*
* In the 'limited' case get_user_pages() for dax is disabled.
*/
if (IS_ENABLED(CONFIG_FS_DAX_LIMITED))
return NULL;
if (!dax_mapping(mapping) || !mapping_mapped(mapping))
return NULL;
pagevec_init(&pvec);
index = 0;
end = -1;
/*
* If we race get_user_pages_fast() here either we'll see the
* elevated page count in the pagevec_lookup and wait, or
* get_user_pages_fast() will see that the page it took a reference
* against is no longer mapped in the page tables and bail to the
* get_user_pages() slow path. The slow path is protected by
* pte_lock() and pmd_lock(). New references are not taken without
* holding those locks, and unmap_mapping_range() will not zero the
* pte or pmd without holding the respective lock, so we are
* guaranteed to either see new references or prevent new
* references from being established.
*/
unmap_mapping_range(mapping, 0, 0, 1);
while (index < end && pagevec_lookup_entries(&pvec, mapping, index,
min(end - index, (pgoff_t)PAGEVEC_SIZE),
indices)) {
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *pvec_ent = pvec.pages[i];
void *entry;
index = indices[i];
if (index >= end)
break;
if (!radix_tree_exceptional_entry(pvec_ent))
continue;
xa_lock_irq(&mapping->i_pages);
entry = get_unlocked_mapping_entry(mapping, index, NULL);
if (entry)
page = dax_busy_page(entry);
put_unlocked_mapping_entry(mapping, index, entry);
xa_unlock_irq(&mapping->i_pages);
if (page)
break;
}
pagevec_remove_exceptionals(&pvec);
pagevec_release(&pvec);
index++;
if (page)
break;
}
return page;
}
EXPORT_SYMBOL_GPL(dax_layout_busy_page);
static int __dax_invalidate_mapping_entry(struct address_space *mapping,
pgoff_t index, bool trunc)
{
@ -912,7 +1009,6 @@ static int dax_load_hole(struct address_space *mapping, void *entry,
unsigned long vaddr = vmf->address;
int ret = VM_FAULT_NOPAGE;
struct page *zero_page;
void *entry2;
pfn_t pfn;
zero_page = ZERO_PAGE(0);
@ -922,13 +1018,8 @@ static int dax_load_hole(struct address_space *mapping, void *entry,
}
pfn = page_to_pfn_t(zero_page);
entry2 = dax_insert_mapping_entry(mapping, vmf, entry, pfn,
RADIX_DAX_ZERO_PAGE, false);
if (IS_ERR(entry2)) {
ret = VM_FAULT_SIGBUS;
goto out;
}
dax_insert_mapping_entry(mapping, vmf, entry, pfn, RADIX_DAX_ZERO_PAGE,
false);
vm_insert_mixed(vmf->vma, vaddr, pfn);
out:
trace_dax_load_hole(inode, vmf, ret);
@ -1240,10 +1331,6 @@ static int dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
entry = dax_insert_mapping_entry(mapping, vmf, entry, pfn,
0, write && !sync);
if (IS_ERR(entry)) {
error = PTR_ERR(entry);
goto error_finish_iomap;
}
/*
* If we are doing synchronous page fault and inode needs fsync,
@ -1327,8 +1414,6 @@ static int dax_pmd_load_hole(struct vm_fault *vmf, struct iomap *iomap,
pfn = page_to_pfn_t(zero_page);
ret = dax_insert_mapping_entry(mapping, vmf, entry, pfn,
RADIX_DAX_PMD | RADIX_DAX_ZERO_PAGE, false);
if (IS_ERR(ret))
goto fallback;
ptl = pmd_lock(vmf->vma->vm_mm, vmf->pmd);
if (!pmd_none(*(vmf->pmd))) {
@ -1450,8 +1535,6 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
entry = dax_insert_mapping_entry(mapping, vmf, entry, pfn,
RADIX_DAX_PMD, write && !sync);
if (IS_ERR(entry))
goto finish_iomap;
/*
* If we are doing synchronous page fault and inode needs fsync,

72
fs/xfs/xfs_file.c
View File

@ -312,7 +312,7 @@ xfs_file_aio_write_checks(
if (error <= 0)
return error;
error = xfs_break_layouts(inode, iolock);
error = xfs_break_layouts(inode, iolock, BREAK_WRITE);
if (error)
return error;
@ -718,6 +718,69 @@ xfs_file_write_iter(
return ret;
}
static void
xfs_wait_dax_page(
struct inode *inode,
bool *did_unlock)
{
struct xfs_inode *ip = XFS_I(inode);
*did_unlock = true;
xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
schedule();
xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
}
static int
xfs_break_dax_layouts(
struct inode *inode,
uint iolock,
bool *did_unlock)
{
struct page *page;
ASSERT(xfs_isilocked(XFS_I(inode), XFS_MMAPLOCK_EXCL));
page = dax_layout_busy_page(inode->i_mapping);
if (!page)
return 0;
return ___wait_var_event(&page->_refcount,
atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE,
0, 0, xfs_wait_dax_page(inode, did_unlock));
}
int
xfs_break_layouts(
struct inode *inode,
uint *iolock,
enum layout_break_reason reason)
{
bool retry;
int error;
ASSERT(xfs_isilocked(XFS_I(inode), XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL));
do {
retry = false;
switch (reason) {
case BREAK_UNMAP:
error = xfs_break_dax_layouts(inode, *iolock, &retry);
if (error || retry)
break;
/* fall through */
case BREAK_WRITE:
error = xfs_break_leased_layouts(inode, iolock, &retry);
break;
default:
WARN_ON_ONCE(1);
error = -EINVAL;
}
} while (error == 0 && retry);
return error;
}
#define XFS_FALLOC_FL_SUPPORTED \
(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE | \
@ -734,7 +797,7 @@ xfs_file_fallocate(
struct xfs_inode *ip = XFS_I(inode);
long error;
enum xfs_prealloc_flags flags = 0;
uint iolock = XFS_IOLOCK_EXCL;
uint iolock = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL;
loff_t new_size = 0;
bool do_file_insert = false;
@ -744,13 +807,10 @@ xfs_file_fallocate(
return -EOPNOTSUPP;
xfs_ilock(ip, iolock);
error = xfs_break_layouts(inode, &iolock);
error = xfs_break_layouts(inode, &iolock, BREAK_UNMAP);
if (error)
goto out_unlock;
xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
iolock |= XFS_MMAPLOCK_EXCL;
if (mode & FALLOC_FL_PUNCH_HOLE) {
error = xfs_free_file_space(ip, offset, len);
if (error)

16
fs/xfs/xfs_inode.h
View File

@ -378,6 +378,20 @@ static inline void xfs_ifunlock(struct xfs_inode *ip)
#define XFS_ILOCK_DEP(flags) (((flags) & XFS_ILOCK_DEP_MASK) \
>> XFS_ILOCK_SHIFT)
/*
* Layouts are broken in the BREAK_WRITE case to ensure that
* layout-holders do not collide with local writes. Additionally,
* layouts are broken in the BREAK_UNMAP case to make sure the
* layout-holder has a consistent view of the file's extent map. While
* BREAK_WRITE breaks can be satisfied by recalling FL_LAYOUT leases,
* BREAK_UNMAP breaks additionally require waiting for busy dax-pages to
* go idle.
*/
enum layout_break_reason {
BREAK_WRITE,
BREAK_UNMAP,
};
/*
* For multiple groups support: if S_ISGID bit is set in the parent
* directory, group of new file is set to that of the parent, and
@ -443,6 +457,8 @@ enum xfs_prealloc_flags {
int xfs_update_prealloc_flags(struct xfs_inode *ip,
enum xfs_prealloc_flags flags);
int xfs_break_layouts(struct inode *inode, uint *iolock,
enum layout_break_reason reason);
/* from xfs_iops.c */
extern void xfs_setup_inode(struct xfs_inode *ip);

8
fs/xfs/xfs_ioctl.c
View File

@ -39,7 +39,6 @@
#include "xfs_icache.h"
#include "xfs_symlink.h"
#include "xfs_trans.h"
#include "xfs_pnfs.h"
#include "xfs_acl.h"
#include "xfs_btree.h"
#include <linux/fsmap.h>
@ -614,7 +613,7 @@ xfs_ioc_space(
struct xfs_inode *ip = XFS_I(inode);
struct iattr iattr;
enum xfs_prealloc_flags flags = 0;
uint iolock = XFS_IOLOCK_EXCL;
uint iolock = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL;
int error;
/*
@ -644,13 +643,10 @@ xfs_ioc_space(
return error;
xfs_ilock(ip, iolock);
error = xfs_break_layouts(inode, &iolock);
error = xfs_break_layouts(inode, &iolock, BREAK_UNMAP);
if (error)
goto out_unlock;
xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
iolock |= XFS_MMAPLOCK_EXCL;
switch (bf->l_whence) {
case 0: /*SEEK_SET*/
break;

18
fs/xfs/xfs_iops.c
View File

@ -37,7 +37,6 @@
#include "xfs_da_btree.h"
#include "xfs_dir2.h"
#include "xfs_trans_space.h"
#include "xfs_pnfs.h"
#include "xfs_iomap.h"
#include <linux/capability.h>
@ -1030,14 +1029,19 @@ xfs_vn_setattr(
int error;
if (iattr->ia_valid & ATTR_SIZE) {
struct xfs_inode *ip = XFS_I(d_inode(dentry));
uint iolock = XFS_IOLOCK_EXCL;
error = xfs_break_layouts(d_inode(dentry), &iolock);
if (error)
return error;
struct inode *inode = d_inode(dentry);
struct xfs_inode *ip = XFS_I(inode);
uint iolock;
xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
iolock = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL;
error = xfs_break_layouts(inode, &iolock, BREAK_UNMAP);
if (error) {
xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
return error;
}
error = xfs_vn_setattr_size(dentry, iattr);
xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
} else {

15
fs/xfs/xfs_pnfs.c
View File

@ -31,19 +31,20 @@
* rules in the page fault path we don't bother.
*/
int
xfs_break_layouts(
xfs_break_leased_layouts(
struct inode *inode,
uint *iolock)
uint *iolock,
bool *did_unlock)
{
struct xfs_inode *ip = XFS_I(inode);
int error;
ASSERT(xfs_isilocked(ip, XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL));
while ((error = break_layout(inode, false) == -EWOULDBLOCK)) {
xfs_iunlock(ip, *iolock);
*did_unlock = true;
error = break_layout(inode, true);
*iolock = XFS_IOLOCK_EXCL;
*iolock &= ~XFS_IOLOCK_SHARED;
*iolock |= XFS_IOLOCK_EXCL;
xfs_ilock(ip, *iolock);
}
@ -120,8 +121,8 @@ xfs_fs_map_blocks(
* Lock out any other I/O before we flush and invalidate the pagecache,
* and then hand out a layout to the remote system. This is very
* similar to direct I/O, except that the synchronization is much more
* complicated. See the comment near xfs_break_layouts for a detailed
* explanation.
* complicated. See the comment near xfs_break_leased_layouts
* for a detailed explanation.
*/
xfs_ilock(ip, XFS_IOLOCK_EXCL);

5
fs/xfs/xfs_pnfs.h
View File

@ -9,10 +9,11 @@ int xfs_fs_map_blocks(struct inode *inode, loff_t offset, u64 length,
int xfs_fs_commit_blocks(struct inode *inode, struct iomap *maps, int nr_maps,
struct iattr *iattr);
int xfs_break_layouts(struct inode *inode, uint *iolock);
int xfs_break_leased_layouts(struct inode *inode, uint *iolock,
bool *did_unlock);
#else
static inline int
xfs_break_layouts(struct inode *inode, uint *iolock)
xfs_break_leased_layouts(struct inode *inode, uint *iolock, bool *did_unlock)
{
return 0;
}

7
include/linux/dax.h
View File

@ -83,6 +83,8 @@ static inline void fs_put_dax(struct dax_device *dax_dev)
struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev);
int dax_writeback_mapping_range(struct address_space *mapping,
struct block_device *bdev, struct writeback_control *wbc);
struct page *dax_layout_busy_page(struct address_space *mapping);
#else
static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
{
@ -103,6 +105,11 @@ static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev)
return NULL;
}
static inline struct page *dax_layout_busy_page(struct address_space *mapping)
{
return NULL;
}
static inline int dax_writeback_mapping_range(struct address_space *mapping,
struct block_device *bdev, struct writeback_control *wbc)
{

36
include/linux/memremap.h
View File

@ -1,7 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_MEMREMAP_H_
#define _LINUX_MEMREMAP_H_
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/percpu-refcount.h>
@ -30,13 +29,6 @@ struct vmem_altmap {
* Specialize ZONE_DEVICE memory into multiple types each having differents
* usage.
*
* MEMORY_DEVICE_HOST:
* Persistent device memory (pmem): struct page might be allocated in different
* memory and architecture might want to perform special actions. It is similar
* to regular memory, in that the CPU can access it transparently. However,
* it is likely to have different bandwidth and latency than regular memory.
* See Documentation/nvdimm/nvdimm.txt for more information.
*
* MEMORY_DEVICE_PRIVATE:
* Device memory that is not directly addressable by the CPU: CPU can neither
* read nor write private memory. In this case, we do still have struct pages
@ -53,11 +45,19 @@ struct vmem_altmap {
* driver can hotplug the device memory using ZONE_DEVICE and with that memory
* type. Any page of a process can be migrated to such memory. However no one
* should be allow to pin such memory so that it can always be evicted.
*
* MEMORY_DEVICE_FS_DAX:
* Host memory that has similar access semantics as System RAM i.e. DMA
* coherent and supports page pinning. In support of coordinating page
* pinning vs other operations MEMORY_DEVICE_FS_DAX arranges for a
* wakeup event whenever a page is unpinned and becomes idle. This
* wakeup is used to coordinate physical address space management (ex:
* fs truncate/hole punch) vs pinned pages (ex: device dma).
*/
enum memory_type {
MEMORY_DEVICE_HOST = 0,
MEMORY_DEVICE_PRIVATE,
MEMORY_DEVICE_PRIVATE = 1,
MEMORY_DEVICE_PUBLIC,
MEMORY_DEVICE_FS_DAX,
};
/*
@ -129,8 +129,6 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
unsigned long vmem_altmap_offset(struct vmem_altmap *altmap);
void vmem_altmap_free(struct vmem_altmap *altmap, unsigned long nr_pfns);
static inline bool is_zone_device_page(const struct page *page);
#else
static inline void *devm_memremap_pages(struct device *dev,
struct dev_pagemap *pgmap)
@ -161,20 +159,6 @@ static inline void vmem_altmap_free(struct vmem_altmap *altmap,
}
#endif /* CONFIG_ZONE_DEVICE */
#if defined(CONFIG_DEVICE_PRIVATE) || defined(CONFIG_DEVICE_PUBLIC)
static inline bool is_device_private_page(const struct page *page)
{
return is_zone_device_page(page) &&
page->pgmap->type == MEMORY_DEVICE_PRIVATE;
}
static inline bool is_device_public_page(const struct page *page)
{
return is_zone_device_page(page) &&
page->pgmap->type == MEMORY_DEVICE_PUBLIC;
}
#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
static inline void put_dev_pagemap(struct dev_pagemap *pgmap)
{
if (pgmap)

71
include/linux/mm.h
View File

@ -821,27 +821,65 @@ static inline bool is_zone_device_page(const struct page *page)
}
#endif
#if defined(CONFIG_DEVICE_PRIVATE) || defined(CONFIG_DEVICE_PUBLIC)
void put_zone_device_private_or_public_page(struct page *page);
DECLARE_STATIC_KEY_FALSE(device_private_key);
#define IS_HMM_ENABLED static_branch_unlikely(&device_private_key)
static inline bool is_device_private_page(const struct page *page);
static inline bool is_device_public_page(const struct page *page);
#else /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
static inline void put_zone_device_private_or_public_page(struct page *page)
#ifdef CONFIG_DEV_PAGEMAP_OPS
void dev_pagemap_get_ops(void);
void dev_pagemap_put_ops(void);
void __put_devmap_managed_page(struct page *page);
DECLARE_STATIC_KEY_FALSE(devmap_managed_key);
static inline bool put_devmap_managed_page(struct page *page)
{
if (!static_branch_unlikely(&devmap_managed_key))
return false;
if (!is_zone_device_page(page))
return false;
switch (page->pgmap->type) {
case MEMORY_DEVICE_PRIVATE:
case MEMORY_DEVICE_PUBLIC:
case MEMORY_DEVICE_FS_DAX:
__put_devmap_managed_page(page);
return true;
default:
break;
}
return false;
}
static inline bool is_device_private_page(const struct page *page)
{
return is_zone_device_page(page) &&
page->pgmap->type == MEMORY_DEVICE_PRIVATE;
}
static inline bool is_device_public_page(const struct page *page)
{
return is_zone_device_page(page) &&
page->pgmap->type == MEMORY_DEVICE_PUBLIC;
}
#else /* CONFIG_DEV_PAGEMAP_OPS */
static inline void dev_pagemap_get_ops(void)
{
}
#define IS_HMM_ENABLED 0
static inline void dev_pagemap_put_ops(void)
{
}
static inline bool put_devmap_managed_page(struct page *page)
{
return false;
}
static inline bool is_device_private_page(const struct page *page)
{
return false;
}
static inline bool is_device_public_page(const struct page *page)
{
return false;
}
#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
#endif /* CONFIG_DEV_PAGEMAP_OPS */
static inline void get_page(struct page *page)
{
@ -859,16 +897,13 @@ static inline void put_page(struct page *page)
page = compound_head(page);
/*
* For private device pages we need to catch refcount transition from
* 2 to 1, when refcount reach one it means the private device page is
* free and we need to inform the device driver through callback. See
* For devmap managed pages we need to catch refcount transition from
* 2 to 1, when refcount reach one it means the page is free and we
* need to inform the device driver through callback. See
* include/linux/memremap.h and HMM for details.
*/
if (IS_HMM_ENABLED && unlikely(is_device_private_page(page) ||
unlikely(is_device_public_page(page)))) {
put_zone_device_private_or_public_page(page);
if (put_devmap_managed_page(page))
return;
}
if (put_page_testzero(page))
__put_page(page);

3
kernel/Makefile
View File

@ -112,7 +112,8 @@ obj-$(CONFIG_JUMP_LABEL) += jump_label.o
obj-$(CONFIG_CONTEXT_TRACKING) += context_tracking.o
obj-$(CONFIG_TORTURE_TEST) += torture.o
obj-$(CONFIG_HAS_IOMEM) += memremap.o
obj-$(CONFIG_HAS_IOMEM) += iomem.o
obj-$(CONFIG_ZONE_DEVICE) += memremap.o
$(obj)/configs.o: $(obj)/config_data.h

167
kernel/iomem.c Normal file
View File

@ -0,0 +1,167 @@
/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/device.h>
#include <linux/types.h>
#include <linux/io.h>
#include <linux/mm.h>
#ifndef ioremap_cache
/* temporary while we convert existing ioremap_cache users to memremap */
__weak void __iomem *ioremap_cache(resource_size_t offset, unsigned long size)
{
return ioremap(offset, size);
}
#endif
#ifndef arch_memremap_wb
static void *arch_memremap_wb(resource_size_t offset, unsigned long size)
{
return (__force void *)ioremap_cache(offset, size);
}
#endif
#ifndef arch_memremap_can_ram_remap
static bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
unsigned long flags)
{
return true;
}
#endif
static void *try_ram_remap(resource_size_t offset, size_t size,
unsigned long flags)
{
unsigned long pfn = PHYS_PFN(offset);
/* In the simple case just return the existing linear address */
if (pfn_valid(pfn) && !PageHighMem(pfn_to_page(pfn)) &&
arch_memremap_can_ram_remap(offset, size, flags))
return __va(offset);
return NULL; /* fallback to arch_memremap_wb */
}
/**
* memremap() - remap an iomem_resource as cacheable memory
* @offset: iomem resource start address
* @size: size of remap
* @flags: any of MEMREMAP_WB, MEMREMAP_WT, MEMREMAP_WC,
* MEMREMAP_ENC, MEMREMAP_DEC
*
* memremap() is "ioremap" for cases where it is known that the resource
* being mapped does not have i/o side effects and the __iomem
* annotation is not applicable. In the case of multiple flags, the different
* mapping types will be attempted in the order listed below until one of
* them succeeds.
*
* MEMREMAP_WB - matches the default mapping for System RAM on
* the architecture. This is usually a read-allocate write-back cache.
* Morever, if MEMREMAP_WB is specified and the requested remap region is RAM
* memremap() will bypass establishing a new mapping and instead return
* a pointer into the direct map.
*
* MEMREMAP_WT - establish a mapping whereby writes either bypass the
* cache or are written through to memory and never exist in a
* cache-dirty state with respect to program visibility. Attempts to
* map System RAM with this mapping type will fail.
*
* MEMREMAP_WC - establish a writecombine mapping, whereby writes may
* be coalesced together (e.g. in the CPU's write buffers), but is otherwise
* uncached. Attempts to map System RAM with this mapping type will fail.
*/
void *memremap(resource_size_t offset, size_t size, unsigned long flags)
{
int is_ram = region_intersects(offset, size,
IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
void *addr = NULL;
if (!flags)
return NULL;
if (is_ram == REGION_MIXED) {
WARN_ONCE(1, "memremap attempted on mixed range %pa size: %#lx\n",
&offset, (unsigned long) size);
return NULL;
}
/* Try all mapping types requested until one returns non-NULL */
if (flags & MEMREMAP_WB) {
/*
* MEMREMAP_WB is special in that it can be satisifed
* from the direct map. Some archs depend on the
* capability of memremap() to autodetect cases where
* the requested range is potentially in System RAM.
*/
if (is_ram == REGION_INTERSECTS)
addr = try_ram_remap(offset, size, flags);
if (!addr)
addr = arch_memremap_wb(offset, size);
}
/*
* If we don't have a mapping yet and other request flags are
* present then we will be attempting to establish a new virtual
* address mapping. Enforce that this mapping is not aliasing
* System RAM.
*/
if (!addr && is_ram == REGION_INTERSECTS && flags != MEMREMAP_WB) {
WARN_ONCE(1, "memremap attempted on ram %pa size: %#lx\n",
&offset, (unsigned long) size);
return NULL;
}
if (!addr && (flags & MEMREMAP_WT))
addr = ioremap_wt(offset, size);
if (!addr && (flags & MEMREMAP_WC))
addr = ioremap_wc(offset, size);
return addr;
}
EXPORT_SYMBOL(memremap);
void memunmap(void *addr)
{
if (is_vmalloc_addr(addr))
iounmap((void __iomem *) addr);
}
EXPORT_SYMBOL(memunmap);
static void devm_memremap_release(struct device *dev, void *res)
{
memunmap(*(void **)res);
}
static int devm_memremap_match(struct device *dev, void *res, void *match_data)
{
return *(void **)res == match_data;
}
void *devm_memremap(struct device *dev, resource_size_t offset,
size_t size, unsigned long flags)
{
void **ptr, *addr;
ptr = devres_alloc_node(devm_memremap_release, sizeof(*ptr), GFP_KERNEL,
dev_to_node(dev));
if (!ptr)
return ERR_PTR(-ENOMEM);
addr = memremap(offset, size, flags);
if (addr) {
*ptr = addr;
devres_add(dev, ptr);
} else {
devres_free(ptr);
return ERR_PTR(-ENXIO);
}
return addr;
}
EXPORT_SYMBOL(devm_memremap);
void devm_memunmap(struct device *dev, void *addr)
{
WARN_ON(devres_release(dev, devm_memremap_release,
devm_memremap_match, addr));
}
EXPORT_SYMBOL(devm_memunmap);

210
kernel/memremap.c
View File

@ -1,15 +1,5 @@
/*
* Copyright(c) 2015 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License 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.
*/
/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright(c) 2015 Intel Corporation. All rights reserved. */
#include <linux/radix-tree.h>
#include <linux/device.h>
#include <linux/types.h>
@ -19,170 +9,8 @@
#include <linux/memory_hotplug.h>
#include <linux/swap.h>
#include <linux/swapops.h>
#include <linux/wait_bit.h>
#ifndef ioremap_cache
/* temporary while we convert existing ioremap_cache users to memremap */
__weak void __iomem *ioremap_cache(resource_size_t offset, unsigned long size)
{
return ioremap(offset, size);
}
#endif
#ifndef arch_memremap_wb
static void *arch_memremap_wb(resource_size_t offset, unsigned long size)
{
return (__force void *)ioremap_cache(offset, size);
}
#endif
#ifndef arch_memremap_can_ram_remap
static bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
unsigned long flags)
{
return true;
}
#endif
static void *try_ram_remap(resource_size_t offset, size_t size,
unsigned long flags)
{
unsigned long pfn = PHYS_PFN(offset);
/* In the simple case just return the existing linear address */
if (pfn_valid(pfn) && !PageHighMem(pfn_to_page(pfn)) &&
arch_memremap_can_ram_remap(offset, size, flags))
return __va(offset);
return NULL; /* fallback to arch_memremap_wb */
}
/**
* memremap() - remap an iomem_resource as cacheable memory
* @offset: iomem resource start address
* @size: size of remap
* @flags: any of MEMREMAP_WB, MEMREMAP_WT, MEMREMAP_WC,
* MEMREMAP_ENC, MEMREMAP_DEC
*
* memremap() is "ioremap" for cases where it is known that the resource
* being mapped does not have i/o side effects and the __iomem
* annotation is not applicable. In the case of multiple flags, the different
* mapping types will be attempted in the order listed below until one of
* them succeeds.
*
* MEMREMAP_WB - matches the default mapping for System RAM on
* the architecture. This is usually a read-allocate write-back cache.
* Morever, if MEMREMAP_WB is specified and the requested remap region is RAM
* memremap() will bypass establishing a new mapping and instead return
* a pointer into the direct map.
*
* MEMREMAP_WT - establish a mapping whereby writes either bypass the
* cache or are written through to memory and never exist in a
* cache-dirty state with respect to program visibility. Attempts to
* map System RAM with this mapping type will fail.
*
* MEMREMAP_WC - establish a writecombine mapping, whereby writes may
* be coalesced together (e.g. in the CPU's write buffers), but is otherwise
* uncached. Attempts to map System RAM with this mapping type will fail.
*/
void *memremap(resource_size_t offset, size_t size, unsigned long flags)
{
int is_ram = region_intersects(offset, size,
IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
void *addr = NULL;
if (!flags)
return NULL;
if (is_ram == REGION_MIXED) {
WARN_ONCE(1, "memremap attempted on mixed range %pa size: %#lx\n",
&offset, (unsigned long) size);
return NULL;
}
/* Try all mapping types requested until one returns non-NULL */
if (flags & MEMREMAP_WB) {
/*
* MEMREMAP_WB is special in that it can be satisifed
* from the direct map. Some archs depend on the
* capability of memremap() to autodetect cases where
* the requested range is potentially in System RAM.
*/
if (is_ram == REGION_INTERSECTS)
addr = try_ram_remap(offset, size, flags);
if (!addr)
addr = arch_memremap_wb(offset, size);
}
/*
* If we don't have a mapping yet and other request flags are
* present then we will be attempting to establish a new virtual
* address mapping. Enforce that this mapping is not aliasing
* System RAM.
*/
if (!addr && is_ram == REGION_INTERSECTS && flags != MEMREMAP_WB) {
WARN_ONCE(1, "memremap attempted on ram %pa size: %#lx\n",
&offset, (unsigned long) size);
return NULL;
}
if (!addr && (flags & MEMREMAP_WT))
addr = ioremap_wt(offset, size);
if (!addr && (flags & MEMREMAP_WC))
addr = ioremap_wc(offset, size);
return addr;
}
EXPORT_SYMBOL(memremap);
void memunmap(void *addr)
{
if (is_vmalloc_addr(addr))
iounmap((void __iomem *) addr);
}
EXPORT_SYMBOL(memunmap);
static void devm_memremap_release(struct device *dev, void *res)
{
memunmap(*(void **)res);
}
static int devm_memremap_match(struct device *dev, void *res, void *match_data)
{
return *(void **)res == match_data;
}
void *devm_memremap(struct device *dev, resource_size_t offset,
size_t size, unsigned long flags)
{
void **ptr, *addr;
ptr = devres_alloc_node(devm_memremap_release, sizeof(*ptr), GFP_KERNEL,
dev_to_node(dev));
if (!ptr)
return ERR_PTR(-ENOMEM);
addr = memremap(offset, size, flags);
if (addr) {
*ptr = addr;
devres_add(dev, ptr);
} else {
devres_free(ptr);
return ERR_PTR(-ENXIO);
}
return addr;
}
EXPORT_SYMBOL(devm_memremap);
void devm_memunmap(struct device *dev, void *addr)
{
WARN_ON(devres_release(dev, devm_memremap_release,
devm_memremap_match, addr));
}
EXPORT_SYMBOL(devm_memunmap);
#ifdef CONFIG_ZONE_DEVICE
static DEFINE_MUTEX(pgmap_lock);
static RADIX_TREE(pgmap_radix, GFP_KERNEL);
#define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1)
@ -473,10 +301,32 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
return pgmap;
}
#endif /* CONFIG_ZONE_DEVICE */
EXPORT_SYMBOL_GPL(get_dev_pagemap);
#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) || IS_ENABLED(CONFIG_DEVICE_PUBLIC)
void put_zone_device_private_or_public_page(struct page *page)
#ifdef CONFIG_DEV_PAGEMAP_OPS
DEFINE_STATIC_KEY_FALSE(devmap_managed_key);
EXPORT_SYMBOL_GPL(devmap_managed_key);
static atomic_t devmap_enable;
/*
* Toggle the static key for ->page_free() callbacks when dev_pagemap
* pages go idle.
*/
void dev_pagemap_get_ops(void)
{
if (atomic_inc_return(&devmap_enable) == 1)
static_branch_enable(&devmap_managed_key);
}
EXPORT_SYMBOL_GPL(dev_pagemap_get_ops);
void dev_pagemap_put_ops(void)
{
if (atomic_dec_and_test(&devmap_enable))
static_branch_disable(&devmap_managed_key);
}
EXPORT_SYMBOL_GPL(dev_pagemap_put_ops);
void __put_devmap_managed_page(struct page *page)
{
int count = page_ref_dec_return(page);
@ -496,5 +346,5 @@ void put_zone_device_private_or_public_page(struct page *page)
} else if (!count)
__put_page(page);
}
EXPORT_SYMBOL(put_zone_device_private_or_public_page);
#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
EXPORT_SYMBOL_GPL(__put_devmap_managed_page);
#endif /* CONFIG_DEV_PAGEMAP_OPS */

5
mm/Kconfig
View File

@ -693,6 +693,9 @@ config ARCH_HAS_HMM
config MIGRATE_VMA_HELPER
bool
config DEV_PAGEMAP_OPS
bool
config HMM
bool
select MIGRATE_VMA_HELPER
@ -713,6 +716,7 @@ config DEVICE_PRIVATE
bool "Unaddressable device memory (GPU memory, ...)"
depends on ARCH_HAS_HMM
select HMM
select DEV_PAGEMAP_OPS
help
Allows creation of struct pages to represent unaddressable device
@ -723,6 +727,7 @@ config DEVICE_PUBLIC
bool "Addressable device memory (like GPU memory)"
depends on ARCH_HAS_HMM
select HMM
select DEV_PAGEMAP_OPS
help
Allows creation of struct pages to represent addressable device

36
mm/gup.c
View File

@ -1459,32 +1459,48 @@ static int __gup_device_huge(unsigned long pfn, unsigned long addr,
return 1;
}
static int __gup_device_huge_pmd(pmd_t pmd, unsigned long addr,
static int __gup_device_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
unsigned long end, struct page **pages, int *nr)
{
unsigned long fault_pfn;
int nr_start = *nr;
fault_pfn = pmd_pfn(pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
return __gup_device_huge(fault_pfn, addr, end, pages, nr);
fault_pfn = pmd_pfn(orig) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
if (!__gup_device_huge(fault_pfn, addr, end, pages, nr))
return 0;
if (unlikely(pmd_val(orig) != pmd_val(*pmdp))) {
undo_dev_pagemap(nr, nr_start, pages);
return 0;
}
return 1;
}
static int __gup_device_huge_pud(pud_t pud, unsigned long addr,
static int __gup_device_huge_pud(pud_t orig, pud_t *pudp, unsigned long addr,
unsigned long end, struct page **pages, int *nr)
{
unsigned long fault_pfn;
int nr_start = *nr;
fault_pfn = pud_pfn(pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
return __gup_device_huge(fault_pfn, addr, end, pages, nr);
fault_pfn = pud_pfn(orig) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
if (!__gup_device_huge(fault_pfn, addr, end, pages, nr))
return 0;
if (unlikely(pud_val(orig) != pud_val(*pudp))) {
undo_dev_pagemap(nr, nr_start, pages);
return 0;
}
return 1;
}
#else
static int __gup_device_huge_pmd(pmd_t pmd, unsigned long addr,
static int __gup_device_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
unsigned long end, struct page **pages, int *nr)
{
BUILD_BUG();
return 0;
}
static int __gup_device_huge_pud(pud_t pud, unsigned long addr,
static int __gup_device_huge_pud(pud_t pud, pud_t *pudp, unsigned long addr,
unsigned long end, struct page **pages, int *nr)
{
BUILD_BUG();
@ -1502,7 +1518,7 @@ static int gup_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
return 0;
if (pmd_devmap(orig))
return __gup_device_huge_pmd(orig, addr, end, pages, nr);
return __gup_device_huge_pmd(orig, pmdp, addr, end, pages, nr);
refs = 0;
page = pmd_page(orig) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
@ -1540,7 +1556,7 @@ static int gup_huge_pud(pud_t orig, pud_t *pudp, unsigned long addr,
return 0;
if (pud_devmap(orig))
return __gup_device_huge_pud(orig, addr, end, pages, nr);
return __gup_device_huge_pud(orig, pudp, addr, end, pages, nr);
refs = 0;
page = pud_page(orig) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);

13
mm/hmm.c
View File

@ -35,15 +35,6 @@
#define PA_SECTION_SIZE (1UL << PA_SECTION_SHIFT)
#if defined(CONFIG_DEVICE_PRIVATE) || defined(CONFIG_DEVICE_PUBLIC)
/*
* Device private memory see HMM (Documentation/vm/hmm.txt) or hmm.h
*/
DEFINE_STATIC_KEY_FALSE(device_private_key);
EXPORT_SYMBOL(device_private_key);
#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
#if IS_ENABLED(CONFIG_HMM_MIRROR)
static const struct mmu_notifier_ops hmm_mmu_notifier_ops;
@ -1167,7 +1158,7 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops,
resource_size_t addr;
int ret;
static_branch_enable(&device_private_key);
dev_pagemap_get_ops();
devmem = devres_alloc_node(&hmm_devmem_release, sizeof(*devmem),
GFP_KERNEL, dev_to_node(device));
@ -1261,7 +1252,7 @@ struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops,
if (res->desc != IORES_DESC_DEVICE_PUBLIC_MEMORY)
return ERR_PTR(-EINVAL);
static_branch_enable(&device_private_key);
dev_pagemap_get_ops();
devmem = devres_alloc_node(&hmm_devmem_release, sizeof(*devmem),
GFP_KERNEL, dev_to_node(device));

3
mm/swap.c
View File

@ -29,6 +29,7 @@
#include <linux/cpu.h>
#include <linux/notifier.h>
#include <linux/backing-dev.h>
#include <linux/memremap.h>
#include <linux/memcontrol.h>
#include <linux/gfp.h>
#include <linux/uio.h>
@ -743,7 +744,7 @@ void release_pages(struct page **pages, int nr)
flags);
locked_pgdat = NULL;
}
put_zone_device_private_or_public_page(page);
put_devmap_managed_page(page);
continue;
}