@@ -51,32 +51,6 @@ static int __init init_dax_wait_table(void)
}
fs_initcall(init_dax_wait_table);
-static long dax_map_atomic(struct block_device *bdev, struct blk_dax_ctl *dax)
-{
- struct request_queue *q = bdev->bd_queue;
- long rc = -EIO;
-
- dax->addr = ERR_PTR(-EIO);
- if (blk_queue_enter(q, true) != 0)
- return rc;
-
- rc = bdev_direct_access(bdev, dax);
- if (rc < 0) {
- dax->addr = ERR_PTR(rc);
- blk_queue_exit(q);
- return rc;
- }
- return rc;
-}
-
-static void dax_unmap_atomic(struct block_device *bdev,
- const struct blk_dax_ctl *dax)
-{
- if (IS_ERR(dax->addr))
- return;
- blk_queue_exit(bdev->bd_queue);
-}
-
static int dax_is_pmd_entry(void *entry)
{
return (unsigned long)entry & RADIX_DAX_PMD;
@@ -549,21 +523,28 @@ static int dax_load_hole(struct address_space *mapping, void **entry,
return ret;
}
-static int copy_user_dax(struct block_device *bdev, sector_t sector, size_t size,
- struct page *to, unsigned long vaddr)
+static int copy_user_dax(struct block_device *bdev, struct dax_inode *dax_inode,
+ sector_t sector, size_t size, struct page *to,
+ unsigned long vaddr)
{
struct blk_dax_ctl dax = {
.sector = sector,
.size = size,
};
void *vto;
+ long rc;
+ int id;
- if (dax_map_atomic(bdev, &dax) < 0)
- return PTR_ERR(dax.addr);
+ id = dax_read_lock();
+ rc = bdev_dax_direct_access(bdev, dax_inode, &dax);
+ if (rc < 0) {
+ dax_read_unlock(id);
+ return rc;
+ }
vto = kmap_atomic(to);
copy_user_page(vto, (void __force *)dax.addr, vaddr, to);
kunmap_atomic(vto);
- dax_unmap_atomic(bdev, &dax);
+ dax_read_unlock(id);
return 0;
}
@@ -731,12 +712,13 @@ static void dax_mapping_entry_mkclean(struct address_space *mapping,
}
static int dax_writeback_one(struct block_device *bdev,
- struct address_space *mapping, pgoff_t index, void *entry)
+ struct dax_inode *dax_inode, struct address_space *mapping,
+ pgoff_t index, void *entry)
{
struct radix_tree_root *page_tree = &mapping->page_tree;
struct blk_dax_ctl dax;
void *entry2, **slot;
- int ret = 0;
+ int ret = 0, id;
/*
* A page got tagged dirty in DAX mapping? Something is seriously
@@ -789,18 +771,20 @@ static int dax_writeback_one(struct block_device *bdev,
dax.size = PAGE_SIZE << dax_radix_order(entry);
/*
- * We cannot hold tree_lock while calling dax_map_atomic() because it
- * eventually calls cond_resched().
+ * bdev_dax_direct_access() may sleep, so cannot hold tree_lock
+ * over its invocation.
*/
- ret = dax_map_atomic(bdev, &dax);
+ id = dax_read_lock();
+ ret = bdev_dax_direct_access(bdev, dax_inode, &dax);
if (ret < 0) {
+ dax_read_unlock(id);
put_locked_mapping_entry(mapping, index, entry);
return ret;
}
if (WARN_ON_ONCE(ret < dax.size)) {
ret = -EIO;
- goto unmap;
+ goto dax_unlock;
}
dax_mapping_entry_mkclean(mapping, index, pfn_t_to_pfn(dax.pfn));
@@ -814,8 +798,8 @@ static int dax_writeback_one(struct block_device *bdev,
spin_lock_irq(&mapping->tree_lock);
radix_tree_tag_clear(page_tree, index, PAGECACHE_TAG_DIRTY);
spin_unlock_irq(&mapping->tree_lock);
- unmap:
- dax_unmap_atomic(bdev, &dax);
+ dax_unlock:
+ dax_read_unlock(id);
put_locked_mapping_entry(mapping, index, entry);
return ret;
@@ -836,6 +820,7 @@ int dax_writeback_mapping_range(struct address_space *mapping,
struct inode *inode = mapping->host;
pgoff_t start_index, end_index;
pgoff_t indices[PAGEVEC_SIZE];
+ struct dax_inode *dax_inode;
struct pagevec pvec;
bool done = false;
int i, ret = 0;
@@ -846,6 +831,10 @@ int dax_writeback_mapping_range(struct address_space *mapping,
if (!mapping->nrexceptional || wbc->sync_mode != WB_SYNC_ALL)
return 0;
+ dax_inode = dax_get_by_host(bdev->bd_disk->disk_name);
+ if (!dax_inode)
+ return -EIO;
+
start_index = wbc->range_start >> PAGE_SHIFT;
end_index = wbc->range_end >> PAGE_SHIFT;
@@ -866,19 +855,23 @@ int dax_writeback_mapping_range(struct address_space *mapping,
break;
}
- ret = dax_writeback_one(bdev, mapping, indices[i],
- pvec.pages[i]);
- if (ret < 0)
+ ret = dax_writeback_one(bdev, dax_inode, mapping,
+ indices[i], pvec.pages[i]);
+ if (ret < 0) {
+ put_dax_inode(dax_inode);
return ret;
+ }
}
}
+ put_dax_inode(dax_inode);
return 0;
}
EXPORT_SYMBOL_GPL(dax_writeback_mapping_range);
static int dax_insert_mapping(struct address_space *mapping,
- struct block_device *bdev, sector_t sector, size_t size,
- void **entryp, struct vm_area_struct *vma, struct vm_fault *vmf)
+ struct block_device *bdev, struct dax_inode *dax_inode,
+ sector_t sector, size_t size, void **entryp,
+ struct vm_area_struct *vma, struct vm_fault *vmf)
{
unsigned long vaddr = vmf->address;
struct blk_dax_ctl dax = {
@@ -887,10 +880,15 @@ static int dax_insert_mapping(struct address_space *mapping,
};
void *ret;
void *entry = *entryp;
+ int id, rc;
- if (dax_map_atomic(bdev, &dax) < 0)
- return PTR_ERR(dax.addr);
- dax_unmap_atomic(bdev, &dax);
+ id = dax_read_lock();
+ rc = bdev_dax_direct_access(bdev, dax_inode, &dax);
+ if (rc < 0) {
+ dax_read_unlock(id);
+ return rc;
+ }
+ dax_read_unlock(id);
ret = dax_insert_mapping_entry(mapping, vmf, entry, dax.sector, 0);
if (IS_ERR(ret))
@@ -947,7 +945,8 @@ static bool dax_range_is_aligned(struct block_device *bdev,
return true;
}
-int __dax_zero_page_range(struct block_device *bdev, sector_t sector,
+int __dax_zero_page_range(struct block_device *bdev,
+ struct dax_inode *dax_inode, sector_t sector,
unsigned int offset, unsigned int length)
{
struct blk_dax_ctl dax = {
@@ -961,10 +960,16 @@ int __dax_zero_page_range(struct block_device *bdev, sector_t sector,
return blkdev_issue_zeroout(bdev, start_sector,
length >> 9, GFP_NOFS, true);
} else {
- if (dax_map_atomic(bdev, &dax) < 0)
- return PTR_ERR(dax.addr);
+ int rc, id;
+
+ id = dax_read_lock();
+ rc = bdev_dax_direct_access(bdev, dax_inode, &dax);
+ if (rc < 0) {
+ dax_read_unlock(id);
+ return rc;
+ }
clear_pmem(dax.addr + offset, length);
- dax_unmap_atomic(bdev, &dax);
+ dax_read_unlock(id);
}
return 0;
}
@@ -983,6 +988,7 @@ dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
struct iov_iter *iter = data;
loff_t end = pos + length, done = 0;
ssize_t ret = 0;
+ int id;
if (iov_iter_rw(iter) == READ) {
end = min(end, i_size_read(inode));
@@ -1007,6 +1013,7 @@ dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
(end - 1) >> PAGE_SHIFT);
}
+ id = dax_read_lock();
while (pos < end) {
unsigned offset = pos & (PAGE_SIZE - 1);
struct blk_dax_ctl dax = { 0 };
@@ -1014,7 +1021,8 @@ dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
dax.sector = dax_iomap_sector(iomap, pos);
dax.size = (length + offset + PAGE_SIZE - 1) & PAGE_MASK;
- map_len = dax_map_atomic(iomap->bdev, &dax);
+ map_len = bdev_dax_direct_access(iomap->bdev, iomap->dax_inode,
+ &dax);
if (map_len < 0) {
ret = map_len;
break;
@@ -1029,7 +1037,6 @@ dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
map_len = copy_from_iter_pmem(dax.addr, map_len, iter);
else
map_len = copy_to_iter(dax.addr, map_len, iter);
- dax_unmap_atomic(iomap->bdev, &dax);
if (map_len <= 0) {
ret = map_len ? map_len : -EFAULT;
break;
@@ -1039,6 +1046,7 @@ dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
length -= map_len;
done += map_len;
}
+ dax_read_unlock(id);
return done ? done : ret;
}
@@ -1151,8 +1159,8 @@ int dax_iomap_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
clear_user_highpage(vmf->cow_page, vaddr);
break;
case IOMAP_MAPPED:
- error = copy_user_dax(iomap.bdev, sector, PAGE_SIZE,
- vmf->cow_page, vaddr);
+ error = copy_user_dax(iomap.bdev, iomap.dax_inode,
+ sector, PAGE_SIZE, vmf->cow_page, vaddr);
break;
default:
WARN_ON_ONCE(1);
@@ -1177,8 +1185,8 @@ int dax_iomap_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
mem_cgroup_count_vm_event(vma->vm_mm, PGMAJFAULT);
major = VM_FAULT_MAJOR;
}
- error = dax_insert_mapping(mapping, iomap.bdev, sector,
- PAGE_SIZE, &entry, vma, vmf);
+ error = dax_insert_mapping(mapping, iomap.bdev, iomap.dax_inode,
+ sector, PAGE_SIZE, &entry, vma, vmf);
/* -EBUSY is fine, somebody else faulted on the same PTE */
if (error == -EBUSY)
error = 0;
@@ -1231,23 +1239,24 @@ static int dax_pmd_insert_mapping(struct vm_area_struct *vma, pmd_t *pmd,
{
struct address_space *mapping = vma->vm_file->f_mapping;
struct block_device *bdev = iomap->bdev;
+ struct dax_inode *dax_inode = iomap->dax_inode;
struct blk_dax_ctl dax = {
.sector = dax_iomap_sector(iomap, pos),
.size = PMD_SIZE,
};
- long length = dax_map_atomic(bdev, &dax);
+ long length;
void *ret;
+ int id;
- if (length < 0) /* dax_map_atomic() failed */
- return VM_FAULT_FALLBACK;
+ id = dax_read_lock();
+ length = bdev_dax_direct_access(bdev, dax_inode, &dax);
if (length < PMD_SIZE)
- goto unmap_fallback;
+ goto unlock_fallback;
if (pfn_t_to_pfn(dax.pfn) & PG_PMD_COLOUR)
- goto unmap_fallback;
+ goto unlock_fallback;
if (!pfn_t_devmap(dax.pfn))
- goto unmap_fallback;
-
- dax_unmap_atomic(bdev, &dax);
+ goto unlock_fallback;
+ dax_read_unlock(id);
ret = dax_insert_mapping_entry(mapping, vmf, *entryp, dax.sector,
RADIX_DAX_PMD);
@@ -1257,8 +1266,8 @@ static int dax_pmd_insert_mapping(struct vm_area_struct *vma, pmd_t *pmd,
return vmf_insert_pfn_pmd(vma, address, pmd, dax.pfn, write);
- unmap_fallback:
- dax_unmap_atomic(bdev, &dax);
+ unlock_fallback:
+ dax_read_unlock(id);
return VM_FAULT_FALLBACK;
}
@@ -355,7 +355,8 @@ static int iomap_dax_zero(loff_t pos, unsigned offset, unsigned bytes,
sector_t sector = iomap->blkno +
(((pos & ~(PAGE_SIZE - 1)) - iomap->offset) >> 9);
- return __dax_zero_page_range(iomap->bdev, sector, offset, bytes);
+ return __dax_zero_page_range(iomap->bdev, iomap->dax_inode, sector,
+ offset, bytes);
}
static loff_t
@@ -65,11 +65,13 @@ void dax_wake_mapping_entry_waiter(struct address_space *mapping,
pgoff_t index, void *entry, bool wake_all);
#ifdef CONFIG_FS_DAX
-int __dax_zero_page_range(struct block_device *bdev, sector_t sector,
+int __dax_zero_page_range(struct block_device *bdev,
+ struct dax_inode *dax_inode, sector_t sector,
unsigned int offset, unsigned int length);
#else
static inline int __dax_zero_page_range(struct block_device *bdev,
- sector_t sector, unsigned int offset, unsigned int length)
+ struct dax_inode *dax_inode, sector_t sector,
+ unsigned int offset, unsigned int length)
{
return -ENXIO;
}
Now that a dax_inode is plumbed through all dax-capable drivers we can switch from block_device_operations to dax_operations for invoking ->direct_access. Signed-off-by: Dan Williams <dan.j.williams@intel.com> --- fs/dax.c | 143 +++++++++++++++++++++++++++------------------------ fs/iomap.c | 3 + include/linux/dax.h | 6 +- 3 files changed, 82 insertions(+), 70 deletions(-)