On Fri, Jul 18, 2025 at 1:36 AM Darrick J. Wong <djwong@xxxxxxxxxx> wrote:
>
> From: Darrick J. Wong <djwong@xxxxxxxxxx>
>
> Create a new ->getattr_iflags function so that iomap filesystems can set
> the appropriate in-kernel inode flags on instantiation.
>
> Signed-off-by: "Darrick J. Wong" <djwong@xxxxxxxxxx>
> ---
> include/fuse.h | 7 ++
> lib/fuse.c | 219 ++++++++++++++++++++++++++++++++++++++++++++------------
> 2 files changed, 180 insertions(+), 46 deletions(-)
>
>
> diff --git a/include/fuse.h b/include/fuse.h
> index e2e7c950bf144d..f894dd5da0d106 100644
> --- a/include/fuse.h
> +++ b/include/fuse.h
> @@ -876,6 +876,13 @@ struct fuse_operations {
> uint64_t attr_ino, off_t pos_in, size_t written_in,
> uint32_t ioendflags_in, int error_in,
> uint64_t new_addr_in);
> +
> + /**
> + * Get file attributes and FUSE_IFLAG_* flags. Otherwise the same as
> + * getattr.
> + */
> + int (*getattr_iflags) (const char *path, struct stat *buf,
> + unsigned int *iflags, struct fuse_file_info *fi);
> #endif /* FUSE_USE_VERSION >= 318 */
> };
>
> diff --git a/lib/fuse.c b/lib/fuse.c
> index 8dbf88877dd37c..685d0181e569d0 100644
> --- a/lib/fuse.c
> +++ b/lib/fuse.c
> @@ -123,6 +123,7 @@ struct fuse {
> struct list_head partial_slabs;
> struct list_head full_slabs;
> pthread_t prune_thread;
> + bool want_iflags;
> };
>
> struct lock {
> @@ -144,6 +145,7 @@ struct node {
> char *name;
> uint64_t nlookup;
> int open_count;
> + unsigned int iflags;
> struct timespec stat_updated;
> struct timespec mtime;
> off_t size;
> @@ -1605,6 +1607,24 @@ int fuse_fs_getattr(struct fuse_fs *fs, const char *path, struct stat *buf,
> return fs->op.getattr(path, buf, fi);
> }
>
> +static int fuse_fs_getattr_iflags(struct fuse_fs *fs, const char *path,
> + struct stat *buf, unsigned int *iflags,
> + struct fuse_file_info *fi)
> +{
> + fuse_get_context()->private_data = fs->user_data;
> + if (!fs->op.getattr_iflags)
> + return -ENOSYS;
> +
> + if (fs->debug) {
> + char buf[10];
> +
> + fuse_log(FUSE_LOG_DEBUG, "getattr_iflags[%s] %s\n",
> + file_info_string(fi, buf, sizeof(buf)),
> + path);
> + }
> + return fs->op.getattr_iflags(path, buf, iflags, fi);
> +}
> +
> int fuse_fs_rename(struct fuse_fs *fs, const char *oldpath,
> const char *newpath, unsigned int flags)
> {
> @@ -2417,7 +2437,7 @@ static void update_stat(struct node *node, const struct stat *stbuf)
> }
>
> static int do_lookup(struct fuse *f, fuse_ino_t nodeid, const char *name,
> - struct fuse_entry_param *e)
> + struct fuse_entry_param *e, unsigned int *iflags)
> {
> struct node *node;
>
> @@ -2435,25 +2455,59 @@ static int do_lookup(struct fuse *f, fuse_ino_t nodeid, const char *name,
> pthread_mutex_unlock(&f->lock);
> }
> set_stat(f, e->ino, &e->attr);
> + *iflags = node->iflags;
> + return 0;
> +}
> +
> +static int lookup_and_update(struct fuse *f, fuse_ino_t nodeid,
> + const char *name, struct fuse_entry_param *e,
> + unsigned int iflags)
> +{
> + struct node *node;
> +
> + node = find_node(f, nodeid, name);
> + if (node == NULL)
> + return -ENOMEM;
> +
> + e->ino = node->nodeid;
> + e->generation = node->generation;
> + e->entry_timeout = f->conf.entry_timeout;
> + e->attr_timeout = f->conf.attr_timeout;
> + if (f->conf.auto_cache) {
> + pthread_mutex_lock(&f->lock);
> + update_stat(node, &e->attr);
> + pthread_mutex_unlock(&f->lock);
> + }
> + set_stat(f, e->ino, &e->attr);
> + node->iflags = iflags;
> return 0;
> }
>
> static int lookup_path(struct fuse *f, fuse_ino_t nodeid,
> const char *name, const char *path,
> - struct fuse_entry_param *e, struct fuse_file_info *fi)
> + struct fuse_entry_param *e, unsigned int *iflags,
> + struct fuse_file_info *fi)
> {
> int res;
>
> memset(e, 0, sizeof(struct fuse_entry_param));
> - res = fuse_fs_getattr(f->fs, path, &e->attr, fi);
> - if (res == 0) {
> - res = do_lookup(f, nodeid, name, e);
> - if (res == 0 && f->conf.debug) {
> - fuse_log(FUSE_LOG_DEBUG, " NODEID: %llu\n",
> - (unsigned long long) e->ino);
> - }
> - }
> - return res;
> + *iflags = 0;
> + if (f->want_iflags)
> + res = fuse_fs_getattr_iflags(f->fs, path, &e->attr, iflags, fi);
> + else
> + res = fuse_fs_getattr(f->fs, path, &e->attr, fi);
> + if (res)
> + return res;
> +
> + res = lookup_and_update(f, nodeid, name, e, *iflags);
> + if (res)
> + return res;
> +
> + if (f->conf.debug)
> + fuse_log(FUSE_LOG_DEBUG, " NODEID: %llu iflags 0x%x\n",
> + (unsigned long long) e->ino, *iflags);
> +
> + return 0;
> }
>
> static struct fuse_context_i *fuse_get_context_internal(void)
> @@ -2537,11 +2591,17 @@ static inline void reply_err(fuse_req_t req, int err)
> }
>
> static void reply_entry(fuse_req_t req, const struct fuse_entry_param *e,
> - int err)
> + unsigned int iflags, int err)
> {
> if (!err) {
> struct fuse *f = req_fuse(req);
> - if (fuse_reply_entry(req, e) == -ENOENT) {
> + int entry_res;
> +
> + if (f->want_iflags)
> + entry_res = fuse_reply_entry_iflags(req, e, iflags);
> + else
> + entry_res = fuse_reply_entry(req, e);
> + if (entry_res == -ENOENT) {
> /* Skip forget for negative result */
> if (e->ino != 0)
> forget_node(f, e->ino, 1);
> @@ -2582,6 +2642,9 @@ static void fuse_lib_init(void *data, struct fuse_conn_info *conn)
> /* Disable the receiving and processing of FUSE_INTERRUPT requests */
> conn->no_interrupt = 1;
> }
> +
> + if (fuse_get_feature_flag(conn, FUSE_CAP_IOMAP))
> + f->want_iflags = true;
> }
>
> void fuse_fs_destroy(struct fuse_fs *fs)
> @@ -2605,6 +2668,7 @@ static void fuse_lib_lookup(fuse_req_t req, fuse_ino_t parent,
> struct fuse *f = req_fuse_prepare(req);
> struct fuse_entry_param e;
> char *path;
> + unsigned int iflags = 0;
> int err;
> struct node *dot = NULL;
>
> @@ -2619,7 +2683,7 @@ static void fuse_lib_lookup(fuse_req_t req, fuse_ino_t parent,
> dot = get_node_nocheck(f, parent);
> if (dot == NULL) {
> pthread_mutex_unlock(&f->lock);
> - reply_entry(req, &e, -ESTALE);
> + reply_entry(req, &e, -ESTALE, 0);
> return;
> }
> dot->refctr++;
> @@ -2639,7 +2703,7 @@ static void fuse_lib_lookup(fuse_req_t req, fuse_ino_t parent,
> if (f->conf.debug)
> fuse_log(FUSE_LOG_DEBUG, "LOOKUP %s\n", path);
> fuse_prepare_interrupt(f, req, &d);
> - err = lookup_path(f, parent, name, path, &e, NULL);
> + err = lookup_path(f, parent, name, path, &e, &iflags, NULL);
> if (err == -ENOENT && f->conf.negative_timeout != 0.0) {
> e.ino = 0;
> e.entry_timeout = f->conf.negative_timeout;
> @@ -2653,7 +2717,7 @@ static void fuse_lib_lookup(fuse_req_t req, fuse_ino_t parent,
> unref_node(f, dot);
> pthread_mutex_unlock(&f->lock);
> }
> - reply_entry(req, &e, err);
> + reply_entry(req, &e, iflags, err);
> }
>
> static void do_forget(struct fuse *f, fuse_ino_t ino, uint64_t nlookup)
> @@ -2689,6 +2753,7 @@ static void fuse_lib_getattr(fuse_req_t req, fuse_ino_t ino,
> struct fuse *f = req_fuse_prepare(req);
> struct stat buf;
> char *path;
> + unsigned int iflags = 0;
> int err;
>
> memset(&buf, 0, sizeof(buf));
> @@ -2700,7 +2765,11 @@ static void fuse_lib_getattr(fuse_req_t req, fuse_ino_t ino,
> if (!err) {
> struct fuse_intr_data d;
> fuse_prepare_interrupt(f, req, &d);
> - err = fuse_fs_getattr(f->fs, path, &buf, fi);
> + if (f->want_iflags)
> + err = fuse_fs_getattr_iflags(f->fs, path, &buf,
> + &iflags, fi);
> + else
> + err = fuse_fs_getattr(f->fs, path, &buf, fi);
> fuse_finish_interrupt(f, req, &d);
> free_path(f, ino, path);
> }
> @@ -2713,9 +2782,14 @@ static void fuse_lib_getattr(fuse_req_t req, fuse_ino_t ino,
> buf.st_nlink--;
> if (f->conf.auto_cache)
> update_stat(node, &buf);
> + node->iflags = iflags;
> pthread_mutex_unlock(&f->lock);
> set_stat(f, ino, &buf);
> - fuse_reply_attr(req, &buf, f->conf.attr_timeout);
> + if (f->want_iflags)
> + fuse_reply_attr_iflags(req, &buf, iflags,
> + f->conf.attr_timeout);
> + else
> + fuse_reply_attr(req, &buf, f->conf.attr_timeout);
> } else
> reply_err(req, err);
> }
> @@ -2802,6 +2876,7 @@ static void fuse_lib_setattr(fuse_req_t req, fuse_ino_t ino, struct stat *attr,
> struct fuse *f = req_fuse_prepare(req);
> struct stat buf;
> char *path;
> + unsigned int iflags = 0;
> int err;
>
> memset(&buf, 0, sizeof(buf));
> @@ -2860,19 +2935,30 @@ static void fuse_lib_setattr(fuse_req_t req, fuse_ino_t ino, struct stat *attr,
> err = fuse_fs_utimens(f->fs, path, tv, fi);
> }
> if (!err) {
> - err = fuse_fs_getattr(f->fs, path, &buf, fi);
> + if (f->want_iflags)
> + err = fuse_fs_getattr_iflags(f->fs, path, &buf,
> + &iflags, fi);
> + else
> + err = fuse_fs_getattr(f->fs, path, &buf, fi);
> }
> fuse_finish_interrupt(f, req, &d);
> free_path(f, ino, path);
> }
> if (!err) {
> - if (f->conf.auto_cache) {
> - pthread_mutex_lock(&f->lock);
> - update_stat(get_node(f, ino), &buf);
> - pthread_mutex_unlock(&f->lock);
> - }
> + struct node *node;
> +
> + pthread_mutex_lock(&f->lock);
> + node = get_node(f, ino);
> + if (f->conf.auto_cache)
> + update_stat(node, &buf);
> + node->iflags = iflags;
> + pthread_mutex_unlock(&f->lock);
> set_stat(f, ino, &buf);
> - fuse_reply_attr(req, &buf, f->conf.attr_timeout);
> + if (f->want_iflags)
> + fuse_reply_attr_iflags(req, &buf, iflags,
> + f->conf.attr_timeout);
> + else
> + fuse_reply_attr(req, &buf, f->conf.attr_timeout);
> } else
> reply_err(req, err);
> }
> @@ -2923,6 +3009,7 @@ static void fuse_lib_mknod(fuse_req_t req, fuse_ino_t parent, const char *name,
> struct fuse *f = req_fuse_prepare(req);
> struct fuse_entry_param e;
> char *path;
> + unsigned int iflags = 0;
> int err;
>
> err = get_path_name(f, parent, name, &path);
> @@ -2939,7 +3026,7 @@ static void fuse_lib_mknod(fuse_req_t req, fuse_ino_t parent, const char *name,
> err = fuse_fs_create(f->fs, path, mode, &fi);
> if (!err) {
> err = lookup_path(f, parent, name, path, &e,
> - &fi);
> + &iflags, &fi);
> fuse_fs_release(f->fs, path, &fi);
> }
> }
> @@ -2947,12 +3034,12 @@ static void fuse_lib_mknod(fuse_req_t req, fuse_ino_t parent, const char *name,
> err = fuse_fs_mknod(f->fs, path, mode, rdev);
> if (!err)
> err = lookup_path(f, parent, name, path, &e,
> - NULL);
> + &iflags, NULL);
> }
> fuse_finish_interrupt(f, req, &d);
> free_path(f, parent, path);
> }
> - reply_entry(req, &e, err);
> + reply_entry(req, &e, iflags, err);
> }
>
> static void fuse_lib_mkdir(fuse_req_t req, fuse_ino_t parent, const char *name,
> @@ -2961,6 +3048,7 @@ static void fuse_lib_mkdir(fuse_req_t req, fuse_ino_t parent, const char *name,
> struct fuse *f = req_fuse_prepare(req);
> struct fuse_entry_param e;
> char *path;
> + unsigned int iflags = 0;
> int err;
>
> err = get_path_name(f, parent, name, &path);
> @@ -2970,11 +3058,12 @@ static void fuse_lib_mkdir(fuse_req_t req, fuse_ino_t parent, const char *name,
> fuse_prepare_interrupt(f, req, &d);
> err = fuse_fs_mkdir(f->fs, path, mode);
> if (!err)
> - err = lookup_path(f, parent, name, path, &e, NULL);
> + err = lookup_path(f, parent, name, path, &e, &iflags,
> + NULL);
> fuse_finish_interrupt(f, req, &d);
> free_path(f, parent, path);
> }
> - reply_entry(req, &e, err);
> + reply_entry(req, &e, iflags, err);
> }
>
> static void fuse_lib_unlink(fuse_req_t req, fuse_ino_t parent,
> @@ -3044,6 +3133,7 @@ static void fuse_lib_symlink(fuse_req_t req, const char *linkname,
> struct fuse *f = req_fuse_prepare(req);
> struct fuse_entry_param e;
> char *path;
> + unsigned int iflags = 0;
> int err;
>
> err = get_path_name(f, parent, name, &path);
> @@ -3053,11 +3143,12 @@ static void fuse_lib_symlink(fuse_req_t req, const char *linkname,
> fuse_prepare_interrupt(f, req, &d);
> err = fuse_fs_symlink(f->fs, linkname, path);
> if (!err)
> - err = lookup_path(f, parent, name, path, &e, NULL);
> + err = lookup_path(f, parent, name, path, &e, &iflags,
> + NULL);
> fuse_finish_interrupt(f, req, &d);
> free_path(f, parent, path);
> }
> - reply_entry(req, &e, err);
> + reply_entry(req, &e, iflags, err);
> }
>
> static void fuse_lib_rename(fuse_req_t req, fuse_ino_t olddir,
> @@ -3105,6 +3196,7 @@ static void fuse_lib_link(fuse_req_t req, fuse_ino_t ino, fuse_ino_t newparent,
> struct fuse_entry_param e;
> char *oldpath;
> char *newpath;
> + unsigned int iflags = 0;
> int err;
>
> err = get_path2(f, ino, NULL, newparent, newname,
> @@ -3116,11 +3208,11 @@ static void fuse_lib_link(fuse_req_t req, fuse_ino_t ino, fuse_ino_t newparent,
> err = fuse_fs_link(f->fs, oldpath, newpath);
> if (!err)
> err = lookup_path(f, newparent, newname, newpath,
> - &e, NULL);
> + &e, &iflags, NULL);
> fuse_finish_interrupt(f, req, &d);
> free_path2(f, ino, newparent, NULL, NULL, oldpath, newpath);
> }
> - reply_entry(req, &e, err);
> + reply_entry(req, &e, iflags, err);
> }
>
> static void fuse_do_release(struct fuse *f, fuse_ino_t ino, const char *path,
> @@ -3163,6 +3255,7 @@ static void fuse_lib_create(fuse_req_t req, fuse_ino_t parent,
> struct fuse_intr_data d;
> struct fuse_entry_param e;
> char *path;
> + unsigned int iflags;
> int err;
>
> err = get_path_name(f, parent, name, &path);
> @@ -3170,7 +3263,8 @@ static void fuse_lib_create(fuse_req_t req, fuse_ino_t parent,
> fuse_prepare_interrupt(f, req, &d);
> err = fuse_fs_create(f->fs, path, mode, fi);
> if (!err) {
> - err = lookup_path(f, parent, name, path, &e, fi);
> + err = lookup_path(f, parent, name, path, &e,
> + &iflags, fi);
> if (err)
> fuse_fs_release(f->fs, path, fi);
> else if (!S_ISREG(e.attr.st_mode)) {
> @@ -3190,10 +3284,18 @@ static void fuse_lib_create(fuse_req_t req, fuse_ino_t parent,
> fuse_finish_interrupt(f, req, &d);
> }
> if (!err) {
> + int create_res;
> +
> pthread_mutex_lock(&f->lock);
> get_node(f, e.ino)->open_count++;
> pthread_mutex_unlock(&f->lock);
> - if (fuse_reply_create(req, &e, fi) == -ENOENT) {
> +
> + if (f->want_iflags)
> + create_res = fuse_reply_create_iflags(req, &e, iflags,
> + fi);
> + else
> + create_res = fuse_reply_create(req, &e, fi);
> + if (create_res == -ENOENT) {
> /* The open syscall was interrupted, so it
> must be cancelled */
> fuse_do_release(f, e.ino, path, fi);
> @@ -3227,13 +3329,21 @@ static void open_auto_cache(struct fuse *f, fuse_ino_t ino, const char *path,
> if (diff_timespec(&now, &node->stat_updated) >
> f->conf.ac_attr_timeout) {
> struct stat stbuf;
> + unsigned int iflags = 0;
> int err;
> +
> pthread_mutex_unlock(&f->lock);
> - err = fuse_fs_getattr(f->fs, path, &stbuf, fi);
> + if (f->want_iflags)
> + err = fuse_fs_getattr_iflags(f->fs, path,
> + &stbuf, &iflags,
> + fi);
> + else
> + err = fuse_fs_getattr(f->fs, path, &stbuf, fi);
> pthread_mutex_lock(&f->lock);
> - if (!err)
> + if (!err) {
> update_stat(node, &stbuf);
> - else
> + node->iflags = iflags;
> + } else
> node->cache_valid = 0;
> }
> }
> @@ -3562,6 +3672,7 @@ static int fill_dir_plus(void *dh_, const char *name, const struct stat *statp,
> .ino = 0,
> };
> struct fuse *f = dh->fuse;
> + unsigned int iflags = 0;
> int res;
>
> if ((flags & ~FUSE_FILL_DIR_PLUS) != 0) {
> @@ -3586,6 +3697,7 @@ static int fill_dir_plus(void *dh_, const char *name, const struct stat *statp,
>
> if (off) {
> size_t newlen;
> + size_t thislen;
>
> if (dh->filled) {
> dh->error = -EIO;
> @@ -3601,7 +3713,8 @@ static int fill_dir_plus(void *dh_, const char *name, const struct stat *statp,
>
> if (statp && (flags & FUSE_FILL_DIR_PLUS)) {
> if (!is_dot_or_dotdot(name)) {
> - res = do_lookup(f, dh->nodeid, name, &e);
> + res = do_lookup(f, dh->nodeid, name, &e,
> + &iflags);
> if (res) {
> dh->error = res;
> return 1;
> @@ -3609,10 +3722,17 @@ static int fill_dir_plus(void *dh_, const char *name, const struct stat *statp,
> }
> }
>
> - newlen = dh->len +
> - fuse_add_direntry_plus(dh->req, dh->contents + dh->len,
> - dh->needlen - dh->len, name,
> - &e, off);
> + if (f->want_iflags)
> + thislen = fuse_add_direntry_plus_iflags(dh->req,
> + dh->contents + dh->len,
> + dh->needlen - dh->len, name, iflags,
> + &e, off);
> + else
> + thislen = fuse_add_direntry_plus(dh->req,
> + dh->contents + dh->len,
> + dh->needlen - dh->len, name, &e, off);
> + newlen = dh->len + thislen;
> +
> if (newlen > dh->needlen)
> return 1;
> dh->len = newlen;
> @@ -3679,6 +3799,7 @@ static int readdir_fill(struct fuse *f, fuse_req_t req, fuse_ino_t ino,
> static int readdir_fill_from_list(fuse_req_t req, struct fuse_dh *dh,
> off_t off, enum fuse_readdir_flags flags)
> {
> + struct fuse *f = req_fuse_prepare(req);
> off_t pos;
> struct fuse_direntry *de = dh->first;
> int res;
> @@ -3699,6 +3820,7 @@ static int readdir_fill_from_list(fuse_req_t req, struct fuse_dh *dh,
> unsigned rem = dh->needlen - dh->len;
> unsigned thislen;
> unsigned newlen;
> + unsigned int iflags = 0;
> pos++;
>
> if (flags & FUSE_READDIR_PLUS) {
> @@ -3710,14 +3832,19 @@ static int readdir_fill_from_list(fuse_req_t req, struct fuse_dh *dh,
> if (de->flags & FUSE_FILL_DIR_PLUS &&
> !is_dot_or_dotdot(de->name)) {
> res = do_lookup(dh->fuse, dh->nodeid,
> - de->name, &e);
> + de->name, &e, &iflags);
> if (res) {
> dh->error = res;
> return 1;
> }
> }
>
> - thislen = fuse_add_direntry_plus(req, p, rem,
> + if (f->want_iflags)
> + thislen = fuse_add_direntry_plus_iflags(req, p,
> + rem, de->name, iflags,
> + &e, pos);
> + else
> + thislen = fuse_add_direntry_plus(req, p, rem,
> de->name, &e, pos);
All those conditional statements look pretty moot.
Can't we just force iflags to 0 if (!f->want_iflags)
and always call the *_iflags functions?
Thanks,
Amir.
