From: Goldwyn Rodrigues
These functions are required for btrfs dax support.
Signed-off-by: Goldwyn Rodrigues
---
fs/dax.c| 35 ---
include/linux/dax.h | 16
2 files changed, 40 insertions(+), 11 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index 9bcce89ea18e..4578640af631 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -244,7 +244,7 @@ static void put_unlocked_entry(struct xa_state *xas, void
*entry)
* dropped the xa_lock, so we know the xa_state is stale and must be reset
* before use.
*/
-static void dax_unlock_entry(struct xa_state *xas, void *entry)
+void dax_unlock_entry(struct xa_state *xas, void *entry)
{
void *old;
@@ -256,6 +256,7 @@ static void dax_unlock_entry(struct xa_state *xas, void
*entry)
BUG_ON(!dax_is_locked(old));
dax_wake_entry(xas, entry, false);
}
+EXPORT_SYMBOL(dax_unlock_entry);
/*
* Return: The entry stored at this location before it was locked.
@@ -448,7 +449,7 @@ void dax_unlock_mapping_entry(struct page *page)
* a VM_FAULT code, encoded as an xarray internal entry. The ERR_PTR values
* overlap with xarray value entries.
*/
-static void *grab_mapping_entry(struct xa_state *xas,
+void *grab_mapping_entry(struct xa_state *xas,
struct address_space *mapping, unsigned long size_flag)
{
unsigned long index = xas->xa_index;
@@ -531,6 +532,7 @@ static void *grab_mapping_entry(struct xa_state *xas,
xas_unlock_irq(xas);
return xa_mk_internal(VM_FAULT_FALLBACK);
}
+EXPORT_SYMBOL(grab_mapping_entry);
/**
* dax_layout_busy_page - find first pinned page in @mapping
@@ -654,7 +656,7 @@ int dax_invalidate_mapping_entry_sync(struct address_space
*mapping,
return __dax_invalidate_entry(mapping, index, false);
}
-static int copy_user_dax(struct block_device *bdev, struct dax_device *dax_dev,
+int copy_user_dax(struct block_device *bdev, struct dax_device *dax_dev,
sector_t sector, size_t size, struct page *to,
unsigned long vaddr)
{
@@ -679,6 +681,7 @@ static int copy_user_dax(struct block_device *bdev, struct
dax_device *dax_dev,
dax_read_unlock(id);
return 0;
}
+EXPORT_SYMBOL(copy_user_dax);
/*
* By this point grab_mapping_entry() has ensured that we have a locked entry
@@ -687,7 +690,7 @@ static int copy_user_dax(struct block_device *bdev, struct
dax_device *dax_dev,
* already in the tree, we will skip the insertion and just dirty the PMD as
* appropriate.
*/
-static void *dax_insert_entry(struct xa_state *xas,
+void *dax_insert_entry(struct xa_state *xas,
struct address_space *mapping, struct vm_fault *vmf,
void *entry, pfn_t pfn, unsigned long flags, bool dirty)
{
@@ -736,6 +739,7 @@ static void *dax_insert_entry(struct xa_state *xas,
xas_unlock_irq(xas);
return entry;
}
+EXPORT_SYMBOL(dax_insert_entry);
static inline
unsigned long pgoff_address(pgoff_t pgoff, struct vm_area_struct *vma)
@@ -962,19 +966,18 @@ static sector_t dax_iomap_sector(struct iomap *iomap,
loff_t pos)
return (iomap->addr + (pos & PAGE_MASK) - iomap->offset) >> 9;
}
-static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
-pfn_t *pfnp)
+int dax_pfn(struct dax_device *dax_dev, struct block_device *bdev,
+ const sector_t sector, size_t size, pfn_t *pfnp)
{
- const sector_t sector = dax_iomap_sector(iomap, pos);
pgoff_t pgoff;
int id, rc;
long length;
- rc = bdev_dax_pgoff(iomap->bdev, sector, size, );
+ rc = bdev_dax_pgoff(bdev, sector, size, );
if (rc)
return rc;
id = dax_read_lock();
- length = dax_direct_access(iomap->dax_dev, pgoff, PHYS_PFN(size),
+ length = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size),
NULL, pfnp);
if (length < 0) {
rc = length;
@@ -993,6 +996,14 @@ static int dax_iomap_pfn(struct iomap *iomap, loff_t pos,
size_t size,
dax_read_unlock(id);
return rc;
}
+EXPORT_SYMBOL(dax_pfn);
+
+static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
+pfn_t *pfnp)
+{
+ const sector_t sector = dax_iomap_sector(iomap, pos);
+ return dax_pfn(iomap->dax_dev, iomap->bdev, sector, size, pfnp);
+}
/*
* The user has performed a load from a hole in the file. Allocating a new
@@ -1001,7 +1012,7 @@ static int dax_iomap_pfn(struct iomap *iomap, loff_t pos,
size_t size,
* If this page is ever written to we will re-fault and change the mapping to
* point to real DAX storage instead.
*/
-static vm_fault_t dax_load_hole(struct xa_state *xas,
+vm_fault_t dax_load_hole(struct xa_state *xas,
struct address_space *mapping, void **entry,
struct vm_fault *vmf)
{
@@ -1017,6 +1028,7 @@ static vm_fault_t dax_load_hole(struct xa_state
