Commit 25f4e702 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Dave Chinner

ext2: use iomap to implement DAX

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarRoss Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: default avatarDave Chinner <david@fromorbit.com>
parent 6750ad71
config EXT2_FS
tristate "Second extended fs support"
select FS_IOMAP if FS_DAX
help
Ext2 is a standard Linux file system for hard disks.
......
......@@ -814,6 +814,7 @@ extern const struct file_operations ext2_file_operations;
/* inode.c */
extern const struct address_space_operations ext2_aops;
extern const struct address_space_operations ext2_nobh_aops;
extern struct iomap_ops ext2_iomap_ops;
/* namei.c */
extern const struct inode_operations ext2_dir_inode_operations;
......
......@@ -22,11 +22,59 @@
#include <linux/pagemap.h>
#include <linux/dax.h>
#include <linux/quotaops.h>
#include <linux/iomap.h>
#include <linux/uio.h>
#include "ext2.h"
#include "xattr.h"
#include "acl.h"
#ifdef CONFIG_FS_DAX
static ssize_t ext2_dax_read_iter(struct kiocb *iocb, struct iov_iter *to)
{
struct inode *inode = iocb->ki_filp->f_mapping->host;
ssize_t ret;
if (!iov_iter_count(to))
return 0; /* skip atime */
inode_lock_shared(inode);
ret = iomap_dax_rw(iocb, to, &ext2_iomap_ops);
inode_unlock_shared(inode);
file_accessed(iocb->ki_filp);
return ret;
}
static ssize_t ext2_dax_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
ssize_t ret;
inode_lock(inode);
ret = generic_write_checks(iocb, from);
if (ret <= 0)
goto out_unlock;
ret = file_remove_privs(file);
if (ret)
goto out_unlock;
ret = file_update_time(file);
if (ret)
goto out_unlock;
ret = iomap_dax_rw(iocb, from, &ext2_iomap_ops);
if (ret > 0 && iocb->ki_pos > i_size_read(inode)) {
i_size_write(inode, iocb->ki_pos);
mark_inode_dirty(inode);
}
out_unlock:
inode_unlock(inode);
if (ret > 0)
ret = generic_write_sync(iocb, ret);
return ret;
}
/*
* The lock ordering for ext2 DAX fault paths is:
*
......@@ -51,7 +99,7 @@ static int ext2_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
}
down_read(&ei->dax_sem);
ret = dax_fault(vma, vmf, ext2_get_block);
ret = iomap_dax_fault(vma, vmf, &ext2_iomap_ops);
up_read(&ei->dax_sem);
if (vmf->flags & FAULT_FLAG_WRITE)
......@@ -156,14 +204,28 @@ int ext2_fsync(struct file *file, loff_t start, loff_t end, int datasync)
return ret;
}
/*
* We have mostly NULL's here: the current defaults are ok for
* the ext2 filesystem.
*/
static ssize_t ext2_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
{
#ifdef CONFIG_FS_DAX
if (IS_DAX(iocb->ki_filp->f_mapping->host))
return ext2_dax_read_iter(iocb, to);
#endif
return generic_file_read_iter(iocb, to);
}
static ssize_t ext2_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
#ifdef CONFIG_FS_DAX
if (IS_DAX(iocb->ki_filp->f_mapping->host))
return ext2_dax_write_iter(iocb, from);
#endif
return generic_file_write_iter(iocb, from);
}
const struct file_operations ext2_file_operations = {
.llseek = generic_file_llseek,
.read_iter = generic_file_read_iter,
.write_iter = generic_file_write_iter,
.read_iter = ext2_file_read_iter,
.write_iter = ext2_file_write_iter,
.unlocked_ioctl = ext2_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = ext2_compat_ioctl,
......
......@@ -32,6 +32,7 @@
#include <linux/buffer_head.h>
#include <linux/mpage.h>
#include <linux/fiemap.h>
#include <linux/iomap.h>
#include <linux/namei.h>
#include <linux/uio.h>
#include "ext2.h"
......@@ -787,6 +788,59 @@ int ext2_get_block(struct inode *inode, sector_t iblock,
}
#ifdef CONFIG_FS_DAX
static int ext2_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
unsigned flags, struct iomap *iomap)
{
unsigned int blkbits = inode->i_blkbits;
unsigned long first_block = offset >> blkbits;
unsigned long max_blocks = (length + (1 << blkbits) - 1) >> blkbits;
bool new = false, boundary = false;
u32 bno;
int ret;
ret = ext2_get_blocks(inode, first_block, max_blocks,
&bno, &new, &boundary, flags & IOMAP_WRITE);
if (ret < 0)
return ret;
iomap->flags = 0;
iomap->bdev = inode->i_sb->s_bdev;
iomap->offset = first_block << blkbits;
if (ret == 0) {
iomap->type = IOMAP_HOLE;
iomap->blkno = IOMAP_NULL_BLOCK;
iomap->length = 1 << blkbits;
} else {
iomap->type = IOMAP_MAPPED;
iomap->blkno = (sector_t)bno << (blkbits - 9);
iomap->length = (u64)ret << blkbits;
iomap->flags |= IOMAP_F_MERGED;
}
if (new)
iomap->flags |= IOMAP_F_NEW;
return 0;
}
static int
ext2_iomap_end(struct inode *inode, loff_t offset, loff_t length,
ssize_t written, unsigned flags, struct iomap *iomap)
{
if (iomap->type == IOMAP_MAPPED &&
written < length &&
(flags & IOMAP_WRITE))
ext2_write_failed(inode->i_mapping, offset + length);
return 0;
}
struct iomap_ops ext2_iomap_ops = {
.iomap_begin = ext2_iomap_begin,
.iomap_end = ext2_iomap_end,
};
#endif /* CONFIG_FS_DAX */
int ext2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
u64 start, u64 len)
{
......@@ -872,10 +926,9 @@ ext2_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
loff_t offset = iocb->ki_pos;
ssize_t ret;
if (IS_DAX(inode))
ret = dax_do_io(iocb, inode, iter, ext2_get_block, NULL,
DIO_LOCKING);
else
if (WARN_ON_ONCE(IS_DAX(inode)))
return -EIO;
ret = blockdev_direct_IO(iocb, inode, iter, ext2_get_block);
if (ret < 0 && iov_iter_rw(iter) == WRITE)
ext2_write_failed(mapping, offset + count);
......
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