On 11/23, Chao Yu wrote: > On 2022/11/12 1:04, Daeho Jeong wrote: > > From: Daeho Jeong <[email protected]> > > > > introduce a new ioctl to replace the whole content of a file atomically, > > which means it induces truncate and content update at the same time. > > We can start it with F2FS_IOC_START_ATOMIC_REPLACE and complete it with > > F2FS_IOC_COMMIT_ATOMIC_WRITE. Or abort it with > > F2FS_IOC_ABORT_ATOMIC_WRITE. > > > > Signed-off-by: Daeho Jeong <[email protected]> > > --- > > v7: changed where to clear FI_ATOMIC_REPLACE > > fixed tentative race condition in f2fs_ioc_start_atomic_write() > > v3: move i_size change after setting atomic write flag > > v2: add undefined ioctl number reported by <[email protected]> > > --- > > fs/f2fs/data.c | 3 +++ > > fs/f2fs/f2fs.h | 1 + > > fs/f2fs/file.c | 21 +++++++++++++++------ > > fs/f2fs/segment.c | 13 ++++++++++++- > > include/uapi/linux/f2fs.h | 1 + > > 5 files changed, 32 insertions(+), 7 deletions(-) > > > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > > index 5f895ddcd64a..bce4dcc3ad78 100644 > > --- a/fs/f2fs/data.c > > +++ b/fs/f2fs/data.c > > @@ -3457,6 +3457,9 @@ static int prepare_atomic_write_begin(struct > > f2fs_sb_info *sbi, > > else if (*blk_addr != NULL_ADDR) > > return 0; > > + if (is_inode_flag_set(inode, FI_ATOMIC_REPLACE)) > > + goto reserve_block; > > + > > /* Look for the block in the original inode */ > > err = __find_data_block(inode, index, &ori_blk_addr); > > if (err) > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > > index e29f9adf60ca..d513ecd17550 100644 > > --- a/fs/f2fs/f2fs.h > > +++ b/fs/f2fs/f2fs.h > > @@ -765,6 +765,7 @@ enum { > > FI_ALIGNED_WRITE, /* enable aligned write */ > > FI_COW_FILE, /* indicate COW file */ > > FI_ATOMIC_COMMITTED, /* indicate atomic commit completed except disk > > sync */ > > + FI_ATOMIC_REPLACE, /* indicate atomic replace */ > > FI_MAX, /* max flag, never be used */ > > }; > > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > > index 7ce629c95f4a..f9a04f6d76cb 100644 > > --- a/fs/f2fs/file.c > > +++ b/fs/f2fs/file.c > > @@ -1984,7 +1984,7 @@ static int f2fs_ioc_getversion(struct file *filp, > > unsigned long arg) > > return put_user(inode->i_generation, (int __user *)arg); > > } > > -static int f2fs_ioc_start_atomic_write(struct file *filp) > > +static int f2fs_ioc_start_atomic_write(struct file *filp, bool truncate) > > { > > struct inode *inode = file_inode(filp); > > struct user_namespace *mnt_userns = file_mnt_user_ns(filp); > > @@ -2053,15 +2053,22 @@ static int f2fs_ioc_start_atomic_write(struct file > > *filp) > > f2fs_write_inode(inode, NULL); > > - isize = i_size_read(inode); > > - fi->original_i_size = isize; > > - f2fs_i_size_write(fi->cow_inode, isize); > > - > > stat_inc_atomic_inode(inode); > > set_inode_flag(inode, FI_ATOMIC_FILE); > > set_inode_flag(fi->cow_inode, FI_COW_FILE); > > clear_inode_flag(fi->cow_inode, FI_INLINE_DATA); > > + > > + isize = i_size_read(inode); > > + fi->original_i_size = isize; > > + if (truncate) { > > + set_inode_flag(inode, FI_ATOMIC_REPLACE); > > + truncate_inode_pages_final(inode->i_mapping); > > + f2fs_i_size_write(inode, 0); > > + isize = 0; > > + } > > + f2fs_i_size_write(fi->cow_inode, isize); > > + > > f2fs_up_write(&fi->i_gc_rwsem[WRITE]); > > f2fs_update_time(sbi, REQ_TIME); > > @@ -4089,7 +4096,9 @@ static long __f2fs_ioctl(struct file *filp, unsigned > > int cmd, unsigned long arg) > > case FS_IOC_GETVERSION: > > return f2fs_ioc_getversion(filp, arg); > > case F2FS_IOC_START_ATOMIC_WRITE: > > - return f2fs_ioc_start_atomic_write(filp); > > + return f2fs_ioc_start_atomic_write(filp, false); > > + case F2FS_IOC_START_ATOMIC_REPLACE: > > + return f2fs_ioc_start_atomic_write(filp, true); > > case F2FS_IOC_COMMIT_ATOMIC_WRITE: > > return f2fs_ioc_commit_atomic_write(filp); > > case F2FS_IOC_ABORT_ATOMIC_WRITE: > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > > index 9cbf88092c78..f2930fffbc7d 100644 > > --- a/fs/f2fs/segment.c > > +++ b/fs/f2fs/segment.c > > @@ -197,6 +197,7 @@ void f2fs_abort_atomic_write(struct inode *inode, bool > > clean) > > fi->cow_inode = NULL; > > release_atomic_write_cnt(inode); > > clear_inode_flag(inode, FI_ATOMIC_COMMITTED); > > + clear_inode_flag(inode, FI_ATOMIC_REPLACE); > > clear_inode_flag(inode, FI_ATOMIC_FILE); > > stat_dec_atomic_inode(inode); > > @@ -261,14 +262,24 @@ static void __complete_revoke_list(struct inode > > *inode, struct list_head *head, > > bool revoke) > > { > > struct revoke_entry *cur, *tmp; > > + pgoff_t start_index = 0; > > + bool truncate = is_inode_flag_set(inode, FI_ATOMIC_REPLACE); > > list_for_each_entry_safe(cur, tmp, head, list) { > > - if (revoke) > > + if (revoke) { > > __replace_atomic_write_block(inode, cur->index, > > cur->old_addr, NULL, true); > > + } else if (truncate) { > > + f2fs_truncate_hole(inode, start_index, cur->index); > > + start_index = cur->index + 1; > > Do we try to truncate from page #0 to page #(index of last page in chain)? > > If so, how about calling f2fs_truncate_hole(, 0, last_index) after the loop?
I think either would be fine. Could you please send a separate patch for this? > > Thanks, > > > + } > > + > > list_del(&cur->list); > > kmem_cache_free(revoke_entry_slab, cur); > > } > > + > > + if (!revoke && truncate) > > + f2fs_do_truncate_blocks(inode, start_index * PAGE_SIZE, false); > > } > > static int __f2fs_commit_atomic_write(struct inode *inode) > > diff --git a/include/uapi/linux/f2fs.h b/include/uapi/linux/f2fs.h > > index 3121d127d5aa..955d440be104 100644 > > --- a/include/uapi/linux/f2fs.h > > +++ b/include/uapi/linux/f2fs.h > > @@ -42,6 +42,7 @@ > > struct f2fs_comp_option) > > #define F2FS_IOC_DECOMPRESS_FILE _IO(F2FS_IOCTL_MAGIC, 23) > > #define F2FS_IOC_COMPRESS_FILE _IO(F2FS_IOCTL_MAGIC, 24) > > +#define F2FS_IOC_START_ATOMIC_REPLACE _IO(F2FS_IOCTL_MAGIC, 25) > > /* > > * should be same as XFS_IOC_GOINGDOWN. > > > _______________________________________________ > Linux-f2fs-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
