On 4/2/24 22:13, Sweet Tea Dorminy wrote:
>
>
> On 2/6/24 09:24, Amir Goldstein wrote:
>> After passthrough read/write, we invalidate a/c/mtime/size attributes
>> if the backing inode attributes differ from FUSE inode attributes.
>>
>> Do the same in fuse_getattr() and after detach of backing inode, so that
>> passthrough mmap read/write changes to a/c/mtime/size attribute of the
>> backing inode will be propagated to the FUSE inode.
>>
>> The rules of invalidating a/c/mtime/size attributes with writeback cache
>> are more complicated, so for now, writeback cache and passthrough cannot
>> be enabled on the same filesystem.
>>
>> Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
>> ---
>> fs/fuse/dir.c | 4 ++++
>> fs/fuse/fuse_i.h | 2 ++
>> fs/fuse/inode.c | 4 ++++
>> fs/fuse/iomode.c | 5 +++-
>> fs/fuse/passthrough.c | 55 ++++++++++++++++++++++++++++++++++++-------
>> 5 files changed, 61 insertions(+), 9 deletions(-)
>>
>> diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
>> index 95330c2ca3d8..7f9d002b8f23 100644
>> --- a/fs/fuse/dir.c
>> +++ b/fs/fuse/dir.c
>> @@ -2118,6 +2118,10 @@ static int fuse_getattr(struct mnt_idmap *idmap,
>> return -EACCES;
>> }
>> + /* Maybe update/invalidate attributes from backing inode */
>> + if (fuse_inode_backing(get_fuse_inode(inode)))
>> + fuse_backing_update_attr_mask(inode, request_mask);
>> +
>> return fuse_update_get_attr(inode, NULL, stat, request_mask,
>> flags);
>> }
>> diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
>> index 98f878a52af1..4b011d31012f 100644
>> --- a/fs/fuse/fuse_i.h
>> +++ b/fs/fuse/fuse_i.h
>> @@ -1456,6 +1456,8 @@ void fuse_backing_files_init(struct fuse_conn *fc);
>> void fuse_backing_files_free(struct fuse_conn *fc);
>> int fuse_backing_open(struct fuse_conn *fc, struct fuse_backing_map
>> *map);
>> int fuse_backing_close(struct fuse_conn *fc, int backing_id);
>> +void fuse_backing_update_attr(struct inode *inode, struct
>> fuse_backing *fb);
>> +void fuse_backing_update_attr_mask(struct inode *inode, u32
>> request_mask);
>> struct fuse_backing *fuse_passthrough_open(struct file *file,
>> struct inode *inode,
>> diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
>> index c26a84439934..c68f005b6e86 100644
>> --- a/fs/fuse/inode.c
>> +++ b/fs/fuse/inode.c
>> @@ -1302,9 +1302,13 @@ static void process_init_reply(struct
>> fuse_mount *fm, struct fuse_args *args,
>> * on a stacked fs (e.g. overlayfs) themselves and with
>> * max_stack_depth == 1, FUSE fs can be stacked as the
>> * underlying fs of a stacked fs (e.g. overlayfs).
>> + *
>> + * For now, writeback cache and passthrough cannot be
>> + * enabled on the same filesystem.
>> */
>> if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH) &&
>> (flags & FUSE_PASSTHROUGH) &&
>> + !fc->writeback_cache &&
>> arg->max_stack_depth > 0 &&
>> arg->max_stack_depth <= FILESYSTEM_MAX_STACK_DEPTH) {
>> fc->passthrough = 1;
>> diff --git a/fs/fuse/iomode.c b/fs/fuse/iomode.c
>> index c545058a01e1..96eb311fe7bd 100644
>> --- a/fs/fuse/iomode.c
>> +++ b/fs/fuse/iomode.c
>> @@ -157,8 +157,11 @@ void fuse_file_uncached_io_end(struct inode *inode)
>> spin_unlock(&fi->lock);
>> if (!uncached_io)
>> wake_up(&fi->direct_io_waitq);
>> - if (oldfb)
>> + if (oldfb) {
>> + /* Maybe update attributes after detaching backing inode */
>> + fuse_backing_update_attr(inode, oldfb);
>> fuse_backing_put(oldfb);
>> + }
>> }
>> /*
>> diff --git a/fs/fuse/passthrough.c b/fs/fuse/passthrough.c
>> index 260e76fc72d5..c1bb80a6e536 100644
>> --- a/fs/fuse/passthrough.c
>> +++ b/fs/fuse/passthrough.c
>> @@ -11,11 +11,8 @@
>> #include <linux/backing-file.h>
>> #include <linux/splice.h>
>> -static void fuse_file_accessed(struct file *file)
>> +static void fuse_backing_accessed(struct inode *inode, struct
>> fuse_backing *fb)
>> {
>> - struct inode *inode = file_inode(file);
>> - struct fuse_inode *fi = get_fuse_inode(inode);
>> - struct fuse_backing *fb = fuse_inode_backing(fi);
>> struct inode *backing_inode = file_inode(fb->file);
>> struct timespec64 atime = inode_get_atime(inode);
>> struct timespec64 batime = inode_get_atime(backing_inode);
>> @@ -25,11 +22,8 @@ static void fuse_file_accessed(struct file *file)
>> fuse_invalidate_atime(inode);
>> }
>> -static void fuse_file_modified(struct file *file)
>> +static void fuse_backing_modified(struct inode *inode, struct
>> fuse_backing *fb)
>> {
>> - struct inode *inode = file_inode(file);
>> - struct fuse_inode *fi = get_fuse_inode(inode);
>> - struct fuse_backing *fb = fuse_inode_backing(fi);
>> struct inode *backing_inode = file_inode(fb->file);
>> struct timespec64 ctime = inode_get_ctime(inode);
>> struct timespec64 mtime = inode_get_mtime(inode);
>> @@ -42,6 +36,51 @@ static void fuse_file_modified(struct file *file)
>> fuse_invalidate_attr_mask(inode, FUSE_STATX_MODSIZE);
>> }
>> +/* Called from fuse_file_uncached_io_end() after detach of backing
>> inode */
>> +void fuse_backing_update_attr(struct inode *inode, struct
>> fuse_backing *fb)
>> +{
>> + fuse_backing_modified(inode, fb);
>> + fuse_backing_accessed(inode, fb);
>> +}
>> +
>> +/* Called from fuse_getattr() - may race with detach of backing inode */
>> +void fuse_backing_update_attr_mask(struct inode *inode, u32
>> request_mask)
>> +{
>> + struct fuse_inode *fi = get_fuse_inode(inode);
>> + struct fuse_backing *fb;
>> +
>> + rcu_read_lock();
>> + fb = fuse_backing_get(fuse_inode_backing(fi));
>> + rcu_read_unlock();
>> + if (!fb)
>> + return;
>> +
>> + if (request_mask & FUSE_STATX_MODSIZE)
>> + fuse_backing_modified(inode, fb);
>> + if (request_mask & STATX_ATIME)
>> + fuse_backing_accessed(inode, fb);
>> +
>> + fuse_backing_put(fb);
>> +}
>> +
>> +static void fuse_file_accessed(struct file *file)
>> +{
>> + struct inode *inode = file_inode(file);
>> + struct fuse_inode *fi = get_fuse_inode(inode);
>> + struct fuse_backing *fb = fuse_inode_backing(fi);
>> +
>> + fuse_backing_accessed(inode, fb);
>> +}
>> +
>> +static void fuse_file_modified(struct file *file)
>> +{
>> + struct inode *inode = file_inode(file);
>> + struct fuse_inode *fi = get_fuse_inode(inode);
>> + struct fuse_backing *fb = fuse_inode_backing(fi);
>> +
>> + fuse_backing_modified(inode, fb);
>> +}
>> +
>> ssize_t fuse_passthrough_read_iter(struct kiocb *iocb, struct
>> iov_iter *iter)
>> {
>> struct file *file = iocb->ki_filp;
>
> I noticed this patch doesn't seem to have made it into 6.9 like the rest
> of these passthrough patches -- may I ask why it didn't make it? I think
> it still makes sense but I might be missing some change between what's
> in 6.9 and this version of the patches.
>
> Thanks!
>
> Sweet Tea
See here please
https://lore.kernel.org/all/CAOQ4uxj8Az6VEZ-Ky5gs33gc0N9hjv4XqL6XC_kc+vsVpaBCOg@xxxxxxxxxxxxxx/
Bernd
