On 2017/7/12 17:06, sunqiuyang wrote:
> From: Qiuyang Sun <sunqiuyang@xxxxxxxxxx>
>
> This patch implements Direct Access (DAX) in F2FS, including:
> - a mount option to choose whether to enable DAX or not
> - read/write and mmap of regular files in the DAX way
> - zero-out of unaligned partial blocks in the DAX way
> - garbage collection of DAX files, by mapping both old and new physical
> addresses of a data page into memory and copy data between them directly
> - incompatibility of DAX with inline data, atomic or volatile write, etc.
>
> Signed-off-by: Qiuyang Sun <sunqiuyang@xxxxxxxxxx>
> ---
> Changlog v5 -> v6:
> - In f2fs_map_blocks(), optimize the separation of new allocated and old
> mapped blocks for the flag F2FS_GET_BLOCK_ZERO, and check the return
> value of zeroout;
> - In f2fs_iomap_begin(), cover the truncation of failed allocation with the
> rwsemaphore i_mmap_sem when necessary;
> - Optimize the order of exception handling in dax_move_data_page().
>
> ---
> fs/f2fs/data.c | 132 ++++++++++++++++++++++++++++++++++++--
> fs/f2fs/f2fs.h | 9 +++
> fs/f2fs/file.c | 192 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
> fs/f2fs/gc.c | 105 ++++++++++++++++++++++++++++--
> fs/f2fs/inline.c | 4 ++
> fs/f2fs/inode.c | 8 ++-
> fs/f2fs/namei.c | 5 ++
> fs/f2fs/super.c | 15 +++++
> 8 files changed, 457 insertions(+), 13 deletions(-)
>
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index 87c1f41..26b908a 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -910,6 +910,15 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
> err = -EIO;
> goto sync_out;
> }
> + /*
> + * If newly allocated blocks are to be zeroed out later,
> + * a single f2fs_map_blocks must not contain both old
> + * and new blocks at the same time.
> + */
> + if (flag == F2FS_GET_BLOCK_ZERO
> + && (map->m_flags & F2FS_MAP_MAPPED)
> + && !(map->m_flags & F2FS_MAP_NEW))
> + goto sync_out;
> if (flag == F2FS_GET_BLOCK_PRE_AIO) {
> if (blkaddr == NULL_ADDR) {
> prealloc++;
> @@ -938,7 +947,8 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
> blkaddr != NEW_ADDR)
> goto sync_out;
> }
> - }
> + } else if (flag == F2FS_GET_BLOCK_ZERO && map->m_flags & F2FS_MAP_NEW)
> + goto sync_out;
>
> if (flag == F2FS_GET_BLOCK_PRE_AIO)
> goto skip;
> @@ -996,6 +1006,12 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
> goto next_dnode;
>
> sync_out:
> + if (flag == F2FS_GET_BLOCK_ZERO && map->m_flags & F2FS_MAP_NEW) {
> + clean_bdev_aliases(inode->i_sb->s_bdev,
> + map->m_pblk, map->m_len);
> + err = sb_issue_zeroout(inode->i_sb, map->m_pblk,
> + map->m_len, GFP_NOFS);
> + }
> f2fs_put_dnode(&dn);
> unlock_out:
> if (create) {
> @@ -1808,16 +1824,19 @@ static int f2fs_write_data_pages(struct address_space *mapping,
> return 0;
> }
>
> -static void f2fs_write_failed(struct address_space *mapping, loff_t to)
> +static void f2fs_write_failed(struct address_space *mapping, loff_t to,
> + bool lock)
> {
> struct inode *inode = mapping->host;
> loff_t i_size = i_size_read(inode);
>
> if (to > i_size) {
> - down_write(&F2FS_I(inode)->i_mmap_sem);
> + if (lock)
> + down_write(&F2FS_I(inode)->i_mmap_sem);
> truncate_pagecache(inode, i_size);
> truncate_blocks(inode, i_size, true);
> - up_write(&F2FS_I(inode)->i_mmap_sem);
> + if (lock)
> + up_write(&F2FS_I(inode)->i_mmap_sem);
> }
> }
>
> @@ -2000,7 +2019,7 @@ static int f2fs_write_begin(struct file *file, struct address_space *mapping,
>
> fail:
> f2fs_put_page(page, 1);
> - f2fs_write_failed(mapping, pos + len);
> + f2fs_write_failed(mapping, pos + len, true);
> return err;
> }
>
> @@ -2077,7 +2096,7 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
> if (err > 0)
> set_inode_flag(inode, FI_UPDATE_WRITE);
> else if (err < 0)
> - f2fs_write_failed(mapping, offset + count);
> + f2fs_write_failed(mapping, offset + count, true);
> }
>
> trace_f2fs_direct_IO_exit(inode, offset, count, rw, err);
> @@ -2274,3 +2293,104 @@ int f2fs_migrate_page(struct address_space *mapping,
> .migratepage = f2fs_migrate_page,
> #endif
> };
> +
> +#ifdef CONFIG_FS_DAX
> +#include <linux/iomap.h>
> +#include <linux/dax.h>
> +
> +static int f2fs_iomap_begin(struct inode *inode, loff_t offset,
> + loff_t length, unsigned int flags, struct iomap *iomap)
> +{
> + struct block_device *bdev;
> + unsigned long first_block = F2FS_BYTES_TO_BLK(offset);
> + unsigned long last_block = F2FS_BYTES_TO_BLK(offset + length - 1);
> + struct f2fs_map_blocks map;
> + int ret;
> +
> + if (WARN_ON_ONCE(f2fs_has_inline_data(inode)))
> + return -ERANGE;
> +
> + map.m_lblk = first_block;
> + map.m_len = last_block - first_block + 1;
> + map.m_next_pgofs = NULL;
> +
> + if (!(flags & IOMAP_WRITE))
> + ret = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_FIEMAP);
> + else {
> + /* i_size should be kept here and changed later in f2fs_iomap_end */
> + loff_t original_i_size = i_size_read(inode);
> +
> + ret = f2fs_map_blocks(inode, &map, 1, F2FS_GET_BLOCK_ZERO);
> + if (i_size_read(inode) > original_i_size) {
> + f2fs_i_size_write(inode, original_i_size);
> + if (ret)
> + f2fs_write_failed(inode->i_mapping,
> + offset + length,
> + !(flags & IOMAP_FAULT));
> + }
> + }
> +
> + if (ret)
> + return ret;
> +
> + iomap->flags = 0;
> + bdev = inode->i_sb->s_bdev;
> + iomap->bdev = bdev;
> + if (blk_queue_dax(bdev->bd_queue))
> + iomap->dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
> + else
> + iomap->dax_dev = NULL;
> + iomap->offset = F2FS_BLK_TO_BYTES((u64)first_block);
> +
> + if (map.m_len == 0) {
> + iomap->type = IOMAP_HOLE;
> + iomap->blkno = IOMAP_NULL_BLOCK;
> + iomap->length = F2FS_BLKSIZE;
> + } else {
> + if (map.m_flags & F2FS_MAP_UNWRITTEN)
> + iomap->type = IOMAP_UNWRITTEN;
> + else if (map.m_flags & F2FS_MAP_MAPPED)
> + iomap->type = IOMAP_MAPPED;
> + else {
> + WARN_ON_ONCE(1);
> + return -EIO;
> + }
> + iomap->blkno =
> + (sector_t)map.m_pblk << F2FS_LOG_SECTORS_PER_BLOCK;
> + iomap->length = F2FS_BLK_TO_BYTES((u64)map.m_len);
> + }
> +
> + if (map.m_flags & F2FS_MAP_NEW)
> + iomap->flags |= IOMAP_F_NEW;
> + return 0;
> +}
> +
> +static int f2fs_iomap_end(struct inode *inode, loff_t offset, loff_t length,
> + ssize_t written, unsigned int flags, struct iomap *iomap)
> +{
> + put_dax(iomap->dax_dev);
> + if (!(flags & IOMAP_WRITE) || (flags & IOMAP_FAULT))
> + return 0;
> +
> + if (offset + written > i_size_read(inode))
> + f2fs_i_size_write(inode, offset + written);
> +
> + if (iomap->offset + iomap->length >
> + ALIGN(i_size_read(inode), F2FS_BLKSIZE)) {
> + block_t written_blk = F2FS_BYTES_TO_BLK(offset + written);
> + block_t end_blk = F2FS_BYTES_TO_BLK(offset + length);
> +
> + if (written_blk < end_blk)
> + f2fs_write_failed(inode->i_mapping, offset + length,
> + true);
!(flags & IOMAP_FAULT)?
> + }
> +
> + f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
> + return 0;
> +}
> +
> +struct iomap_ops f2fs_iomap_ops = {
> + .iomap_begin = f2fs_iomap_begin,
> + .iomap_end = f2fs_iomap_end,
> +};
> +#endif
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 94a88b2..0bbe011 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -91,6 +91,11 @@ struct f2fs_fault_info {
> #define F2FS_MOUNT_LFS 0x00040000
> #define F2FS_MOUNT_USRQUOTA 0x00080000
> #define F2FS_MOUNT_GRPQUOTA 0x00100000
> +#ifdef CONFIG_FS_DAX
> +#define F2FS_MOUNT_DAX 0x00200000 /* Direct Access */
> +#else
> +#define F2FS_MOUNT_DAX 0
> +#endif
>
> #define clear_opt(sbi, option) ((sbi)->mount_opt.opt &= ~F2FS_MOUNT_##option)
> #define set_opt(sbi, option) ((sbi)->mount_opt.opt |= F2FS_MOUNT_##option)
> @@ -479,6 +484,7 @@ struct f2fs_map_blocks {
> #define F2FS_GET_BLOCK_BMAP 3
> #define F2FS_GET_BLOCK_PRE_DIO 4
> #define F2FS_GET_BLOCK_PRE_AIO 5
> +#define F2FS_GET_BLOCK_ZERO 6
>
> /*
> * i_advise uses FADVISE_XXX_BIT. We can add additional hints later.
> @@ -2437,6 +2443,9 @@ void f2fs_invalidate_page(struct page *page, unsigned int offset,
> int f2fs_migrate_page(struct address_space *mapping, struct page *newpage,
> struct page *page, enum migrate_mode mode);
> #endif
> +#ifdef CONFIG_FS_DAX
> +extern struct iomap_ops f2fs_iomap_ops;
> +#endif
>
> /*
> * gc.c
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index a0e6d2c..0e62e97 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -23,6 +23,10 @@
> #include <linux/uio.h>
> #include <linux/uuid.h>
> #include <linux/file.h>
> +#ifdef CONFIG_FS_DAX
> +#include <linux/dax.h>
> +#include <linux/iomap.h>
> +#endif
>
> #include "f2fs.h"
> #include "node.h"
> @@ -121,6 +125,64 @@ static int f2fs_vm_page_mkwrite(struct vm_fault *vmf)
> .page_mkwrite = f2fs_vm_page_mkwrite,
> };
>
> +#ifdef CONFIG_FS_DAX
> +static int f2fs_dax_huge_fault(struct vm_fault *vmf,
> + enum page_entry_size pe_size)
> +{
> + int result;
> + struct inode *inode = file_inode(vmf->vma->vm_file);
> + struct super_block *sb = inode->i_sb;
> + bool write = vmf->flags & FAULT_FLAG_WRITE;
> +
> + if (write) {
> + sb_start_pagefault(sb);
> + file_update_time(vmf->vma->vm_file);
> + }
> + down_read(&F2FS_I(inode)->i_mmap_sem);
> + result = dax_iomap_fault(vmf, pe_size, &f2fs_iomap_ops);
> + up_read(&F2FS_I(inode)->i_mmap_sem);
> + if (write)
> + sb_end_pagefault(sb);
> +
> + return result;
> +}
> +
> +static int f2fs_dax_fault(struct vm_fault *vmf)
> +{
> + return f2fs_dax_huge_fault(vmf, PE_SIZE_PTE);
> +}
> +
> +static int f2fs_dax_pfn_mkwrite(struct vm_fault *vmf)
> +{
> + struct inode *inode = file_inode(vmf->vma->vm_file);
> + struct super_block *sb = inode->i_sb;
> + loff_t size;
> + int ret;
> +
> + sb_start_pagefault(sb);
> + file_update_time(vmf->vma->vm_file);
> + down_read(&F2FS_I(inode)->i_mmap_sem);
> + size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
> + if (vmf->pgoff >= size)
> + ret = VM_FAULT_SIGBUS;
> + else
> + ret = dax_pfn_mkwrite(vmf);
> + up_read(&F2FS_I(inode)->i_mmap_sem);
> + sb_end_pagefault(sb);
> +
> + return ret;
> +}
> +
> +static const struct vm_operations_struct f2fs_dax_vm_ops = {
> + .fault = f2fs_dax_fault,
> + .huge_fault = f2fs_dax_huge_fault,
> + .page_mkwrite = f2fs_dax_fault,
> + .pfn_mkwrite = f2fs_dax_pfn_mkwrite,
> +};
> +#else
> +#define f2fs_dax_vm_ops f2fs_file_vm_ops
> +#endif
> +
> static int get_parent_ino(struct inode *inode, nid_t *pino)
> {
> struct dentry *dentry;
> @@ -436,7 +498,13 @@ static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma)
> return err;
>
> file_accessed(file);
> - vma->vm_ops = &f2fs_file_vm_ops;
> +
> + if (IS_DAX(inode)) {
> + vma->vm_ops = &f2fs_dax_vm_ops;
> + vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE;
> + } else
> + vma->vm_ops = &f2fs_file_vm_ops;
> +
> return 0;
> }
>
> @@ -519,6 +587,17 @@ static int truncate_partial_data_page(struct inode *inode, u64 from,
> if (!offset && !cache_only)
> return 0;
>
> +#ifdef CONFIG_FS_DAX
> + if (IS_DAX(inode)) {
> + int ret;
> +
> + down_read(&F2FS_I(inode)->dio_rwsem[WRITE]);
> + ret = iomap_zero_range(inode, from, PAGE_SIZE - offset,
> + NULL, &f2fs_iomap_ops);
> + up_read(&F2FS_I(inode)->dio_rwsem[WRITE]);
> + return ret;
> + }
> +#endif
> if (cache_only) {
> page = find_lock_page(mapping, index);
> if (page && PageUptodate(page))
> @@ -799,6 +878,18 @@ static int fill_zero(struct inode *inode, pgoff_t index,
> if (!len)
> return 0;
>
> +#ifdef CONFIG_FS_DAX
> + if (IS_DAX(inode)) {
> + int ret;
> +
> + down_read(&F2FS_I(inode)->dio_rwsem[WRITE]);
> + ret = iomap_zero_range(inode,
> + F2FS_BLK_TO_BYTES((loff_t)index) + start,
> + len, NULL, &f2fs_iomap_ops);
> + up_read(&F2FS_I(inode)->dio_rwsem[WRITE]);
> + return ret;
> + }
> +#endif
> f2fs_balance_fs(sbi, true);
>
> f2fs_lock_op(sbi);
> @@ -1121,6 +1212,11 @@ static int f2fs_collapse_range(struct inode *inode, loff_t offset, loff_t len)
> loff_t new_size;
> int ret;
>
> +#ifdef CONFIG_FS_DAX
> + /* The current implementation does not apply to DAX files. */
> + if (IS_DAX(inode))
> + return -EINVAL;
> +#endif
> if (offset + len >= i_size_read(inode))
> return -EINVAL;
>
> @@ -1311,6 +1407,11 @@ static int f2fs_insert_range(struct inode *inode, loff_t offset, loff_t len)
> loff_t new_size;
> int ret = 0;
>
> +#ifdef CONFIG_FS_DAX
> + /* The current implementation does not apply to DAX files. */
> + if (IS_DAX(inode))
> + return -EINVAL;
> +#endif
> new_size = i_size_read(inode) + len;
> ret = inode_newsize_ok(inode, new_size);
> if (ret)
> @@ -1581,6 +1682,10 @@ static int f2fs_ioc_start_atomic_write(struct file *filp)
> struct inode *inode = file_inode(filp);
> int ret;
>
> +#ifdef CONFIG_FS_DAX
> + if (IS_DAX(inode))
> + return -EINVAL;
> +#endif
> if (!inode_owner_or_capable(inode))
> return -EACCES;
>
> @@ -1630,6 +1735,9 @@ static int f2fs_ioc_commit_atomic_write(struct file *filp)
> struct inode *inode = file_inode(filp);
> int ret;
>
> +#ifdef CONFIG_FS_DAX
> + f2fs_bug_on(F2FS_I_SB(inode), IS_DAX(inode));
> +#endif
> if (!inode_owner_or_capable(inode))
> return -EACCES;
>
> @@ -1666,6 +1774,10 @@ static int f2fs_ioc_start_volatile_write(struct file *filp)
> struct inode *inode = file_inode(filp);
> int ret;
>
> +#ifdef CONFIG_FS_DAX
> + if (IS_DAX(inode))
> + return -EINVAL;> +#endif
> if (!inode_owner_or_capable(inode))
> return -EACCES;
>
> @@ -1701,6 +1813,9 @@ static int f2fs_ioc_release_volatile_write(struct file *filp)
> struct inode *inode = file_inode(filp);
> int ret;
>
> +#ifdef CONFIG_FS_DAX
> + f2fs_bug_on(F2FS_I_SB(inode), IS_DAX(inode));
> +#endif
> if (!inode_owner_or_capable(inode))
> return -EACCES;
>
> @@ -1730,6 +1845,9 @@ static int f2fs_ioc_abort_volatile_write(struct file *filp)
> struct inode *inode = file_inode(filp);
> int ret;
>
> +#ifdef CONFIG_FS_DAX
> + f2fs_bug_on(F2FS_I_SB(inode), IS_DAX(inode));
> +#endif
> if (!inode_owner_or_capable(inode))
> return -EACCES;
>
> @@ -2144,6 +2262,10 @@ static int f2fs_ioc_defragment(struct file *filp, unsigned long arg)
> struct f2fs_defragment range;
> int err;
>
> +#ifdef CONFIG_FS_DAX
> + if (IS_DAX(inode))
> + return -EINVAL;
> +#endif
> if (!capable(CAP_SYS_ADMIN))
> return -EPERM;
>
> @@ -2193,6 +2315,10 @@ static int f2fs_move_file_range(struct file *file_in, loff_t pos_in,
> size_t dst_osize;
> int ret;
>
> +#ifdef CONFIG_FS_DAX
> + if (IS_DAX(src) || IS_DAX(dst))
> + return -EINVAL;
> +#endif
> if (file_in->f_path.mnt != file_out->f_path.mnt ||
> src->i_sb != dst->i_sb)
> return -EXDEV;
> @@ -2434,6 +2560,61 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> }
> }
>
> +#ifdef CONFIG_FS_DAX
> +static ssize_t f2fs_dax_read_iter(struct kiocb *iocb, struct iov_iter *to)
> +{
> + struct inode *inode = file_inode(iocb->ki_filp);
> + ssize_t ret;
> +
> + inode_lock_shared(inode);
> +
> + if (!IS_DAX(inode)) {
> + inode_unlock_shared(inode);
> + return generic_file_read_iter(iocb, to);
> + }
> +
> + down_read(&F2FS_I(inode)->dio_rwsem[READ]);
> + ret = dax_iomap_rw(iocb, to, &f2fs_iomap_ops);
> + up_read(&F2FS_I(inode)->dio_rwsem[READ]);
> + inode_unlock_shared(inode);
> +
> + file_accessed(iocb->ki_filp);
> + return ret;
> +}
> +
> +static ssize_t f2fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
> +{
> + if (!iov_iter_count(to))
> + return 0; /* skip atime */
> +
> + if (IS_DAX(file_inode(iocb->ki_filp)))
> + return f2fs_dax_read_iter(iocb, to);
> +
> + return generic_file_read_iter(iocb, to);
> +}
> +
> +static ssize_t f2fs_dax_write_iter(struct kiocb *iocb, struct iov_iter *from)
> +{
> + struct inode *inode = file_inode(iocb->ki_filp);
> + ssize_t ret;
> +
> + ret = file_remove_privs(iocb->ki_filp);
> + if (ret)
> + return ret;
> + ret = file_update_time(iocb->ki_filp);
> + if (ret)
> + return ret;
> +
> + down_read(&F2FS_I(inode)->dio_rwsem[WRITE]);
> + ret = dax_iomap_rw(iocb, from, &f2fs_iomap_ops);
> + up_read(&F2FS_I(inode)->dio_rwsem[WRITE]);
> +
> + return ret;
> +}
> +#else
> +#define f2fs_dax_write_iter __generic_file_write_iter
> +#endif
> +
> static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
> {
> struct file *file = iocb->ki_filp;
> @@ -2455,7 +2636,10 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
> return err;
> }
> blk_start_plug(&plug);
> - ret = __generic_file_write_iter(iocb, from);
> + if (IS_DAX(inode))
> + ret = f2fs_dax_write_iter(iocb, from);
> + else
> + ret = __generic_file_write_iter(iocb, from);
> blk_finish_plug(&plug);
> clear_inode_flag(inode, FI_NO_PREALLOC);
> }
> @@ -2504,7 +2688,11 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
>
> const struct file_operations f2fs_file_operations = {
> .llseek = f2fs_llseek,
> +#ifdef CONFIG_FS_DAX
> + .read_iter = f2fs_file_read_iter,
> +#else
> .read_iter = generic_file_read_iter,
> +#endif
> .write_iter = f2fs_file_write_iter,
> .open = f2fs_file_open,
> .release = f2fs_release_file,
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index fa3d2e2..7d3e424 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -700,6 +700,101 @@ static void move_encrypted_block(struct inode *inode, block_t bidx,
> f2fs_put_page(page, 1);
> }
>
> +#ifdef CONFIG_FS_DAX
> +#include <linux/dax.h>
> +
> +static void dax_move_data_page(struct inode *inode, block_t bidx,
> + unsigned int segno, int off)
> +{
> + struct block_device *bdev = inode->i_sb->s_bdev;
> + struct dax_device *dax_dev;
> + struct dnode_of_data dn;
> + struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> + struct f2fs_summary sum;
> + struct node_info ni;
> + block_t old_blkaddr, new_blkaddr;
> + int err, id;
> + long map_len;
> + pgoff_t pgoff;
> + void *kaddr_old, *kaddr_new;
> + pfn_t pfn;
> +
> + f2fs_bug_on(sbi, f2fs_is_atomic_file(inode));
> +
> + if (!check_valid_map(sbi, segno, off))
> + return;
> +
> + if (blk_queue_dax(bdev->bd_queue))
> + dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
> + else
> + return;
minor cleanup:
if (!blk_queue_dax(bdev->bd_queue))
return;
dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
> +
> + if (!down_write_trylock(&F2FS_I(inode)->i_mmap_sem))
> + goto release;
> +
> + unmap_mapping_range(inode->i_mapping, (loff_t)bidx << PAGE_SHIFT,
> + PAGE_SIZE, 1);
> + /* find the old block address */
> + set_new_dnode(&dn, inode, NULL, NULL, 0);
> + err = get_dnode_of_data(&dn, bidx, LOOKUP_NODE);
> + if (err)
> + goto out;
> + old_blkaddr = dn.data_blkaddr;
> + /* This page is already truncated */
> + if (old_blkaddr == NULL_ADDR)
> + goto put_dn;
> +
> + /* allocate a new block address */
> + get_node_info(sbi, dn.nid, &ni);
> + set_summary(&sum, dn.nid, dn.ofs_in_node, ni.version);
> + allocate_data_block(sbi, NULL, old_blkaddr, &new_blkaddr,
> + &sum, CURSEG_COLD_DATA, NULL, false);
> +
> + /* copy data page from old to new address in dax_bdev */
> + id = dax_read_lock();
> + err = bdev_dax_pgoff(bdev, SECTOR_FROM_BLOCK(old_blkaddr),
> + PAGE_SIZE, &pgoff);
> + if (err)
> + goto recover;
> + map_len = dax_direct_access(dax_dev, pgoff, 1, &kaddr_old, &pfn);
> + if (map_len < 0)
> + goto recover;
> + err = bdev_dax_pgoff(bdev, SECTOR_FROM_BLOCK(new_blkaddr),
> + PAGE_SIZE, &pgoff);
> + if (err)
> + goto recover;
> + map_len = dax_direct_access(dax_dev, pgoff, 1, &kaddr_new, &pfn);
> + if (map_len < 0)
> + goto recover;
> + copy_page((void __force *)kaddr_new, (void __force *)kaddr_old);
> +
> + f2fs_update_data_blkaddr(&dn, new_blkaddr);
> + set_inode_flag(inode, FI_APPEND_WRITE);
> + if (bidx == 0)
> + set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
> +
> +recover:
> + if (err || map_len < 0)
> + __f2fs_replace_block(sbi, &sum, new_blkaddr, old_blkaddr,
> + true, true);
> + dax_read_unlock(id);
> +put_dn:
> + f2fs_put_dnode(&dn);
> +out:
> + unmap_mapping_range(inode->i_mapping, (loff_t)bidx << PAGE_SHIFT,
> + PAGE_SIZE, 1);
> + up_write(&F2FS_I(inode)->i_mmap_sem);
> +release:
> + put_dax(dax_dev);
> +}
> +#else
> +static void dax_move_data_page(struct inode *inode, block_t bidx,
> + unsigned int segno, int off)
> +{
> + return;
> +}
> +#endif
> +
> static void move_data_page(struct inode *inode, block_t bidx, int gc_type,
> unsigned int segno, int off)
> {
> @@ -818,9 +913,9 @@ static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
> if (IS_ERR(inode) || is_bad_inode(inode))
> continue;
>
> - /* if encrypted inode, let's go phase 3 */
> - if (f2fs_encrypted_inode(inode) &&
> - S_ISREG(inode->i_mode)) {
> + /* if DAX or encrypted inode, let's go phase 3 */
> + if (IS_DAX(inode) || (f2fs_encrypted_inode(inode) &&
> + S_ISREG(inode->i_mode))) {
> add_gc_inode(gc_list, inode);
> continue;
> }
> @@ -858,7 +953,9 @@ static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
>
> start_bidx = start_bidx_of_node(nofs, inode)
> + ofs_in_node;
> - if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
> + if (IS_DAX(inode))
> + dax_move_data_page(inode, start_bidx, segno, off);
> + else if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
> move_encrypted_block(inode, start_bidx, segno, off);
> else
> move_data_page(inode, start_bidx, gc_type, segno, off);
> diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
> index e0fd437..fd8b290 100644
> --- a/fs/f2fs/inline.c
> +++ b/fs/f2fs/inline.c
> @@ -28,6 +28,10 @@ bool f2fs_may_inline_data(struct inode *inode)
> if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
> return false;
>
> +#ifdef CONFIG_FS_DAX
> + if (IS_DAX(inode))
> + return false;
> +#endif
> return true;
> }
>
> diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
> index 6cd312a..7741461 100644
> --- a/fs/f2fs/inode.c
> +++ b/fs/f2fs/inode.c
> @@ -43,8 +43,14 @@ void f2fs_set_inode_flags(struct inode *inode)
> new_fl |= S_NOATIME;
> if (flags & FS_DIRSYNC_FL)
> new_fl |= S_DIRSYNC;
> +#ifdef CONFIG_FS_DAX
> + if (test_opt(F2FS_I_SB(inode), DAX) && S_ISREG(inode->i_mode) &&
> + !f2fs_has_inline_data(inode) && !f2fs_encrypted_inode(inode) &&
> + !f2fs_is_atomic_file(inode) && !f2fs_is_volatile_file(inode))
> + new_fl |= S_DAX;
> +#endif
> inode_set_flags(inode, new_fl,
> - S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
> + S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_DAX);
> }
>
> static void __get_inode_rdev(struct inode *inode, struct f2fs_inode *ri)
> diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
> index 760d852..afc52e0 100644
> --- a/fs/f2fs/namei.c
> +++ b/fs/f2fs/namei.c
> @@ -70,6 +70,11 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
> if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode))
> f2fs_set_encrypted_inode(inode);
>
> +#ifdef CONFIG_FS_DAX
> + if (test_opt(sbi, DAX) && S_ISREG(inode->i_mode) &&
> + !f2fs_has_inline_data(inode) && !f2fs_encrypted_inode(inode))
> + inode->i_flags |= S_DAX;
> +#endif
> set_inode_flag(inode, FI_NEW_INODE);
>
> if (test_opt(sbi, INLINE_XATTR))
> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> index 32e4c02..aefe931 100644
> --- a/fs/f2fs/super.c
> +++ b/fs/f2fs/super.c
> @@ -109,6 +109,7 @@ enum {
> Opt_nolazytime,
> Opt_usrquota,
> Opt_grpquota,
> + Opt_dax,
> Opt_err,
> };
>
> @@ -146,6 +147,7 @@ enum {
> {Opt_nolazytime, "nolazytime"},
> {Opt_usrquota, "usrquota"},
> {Opt_grpquota, "grpquota"},
> + {Opt_dax, "dax"},
> {Opt_err, NULL},
> };
>
> @@ -399,6 +401,15 @@ static int parse_options(struct super_block *sb, char *options)
> "quota operations not supported");
> break;
> #endif
> +#ifdef CONFIG_FS_DAX
> + case Opt_dax:
> + set_opt(sbi, DAX);
> + break;
> +#else
> + case Opt_dax:
> + f2fs_msg(sb, KERN_INFO, "dax option not supported");
> + break;
> +#endif
> default:
> f2fs_msg(sb, KERN_ERR,
> "Unrecognized mount option \"%s\" or missing value",
> @@ -814,6 +825,10 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
> if (test_opt(sbi, GRPQUOTA))
> seq_puts(seq, ",grpquota");
> #endif
> +#ifdef CONFIG_FS_DAX
> + if (test_opt(sbi, DAX))
> + seq_puts(seq, ",dax");
> +#endif
Document option of this new feature in f2fs.txt?
Thanks,
>
> return 0;
> }
>
