qemu-kvm/kvm-virtiofsd-optionally-return-inode-pointer-from-lo_do.patch
2021-03-08 12:30:40 +01:00

122 lines
4.4 KiB
Diff

From 24833a2db44e39ec7652779a0fa2e70983b9cb4e Mon Sep 17 00:00:00 2001
From: Stefan Hajnoczi <stefanha@redhat.com>
Date: Wed, 10 Feb 2021 11:15:17 -0300
Subject: [PATCH 06/54] virtiofsd: optionally return inode pointer from
lo_do_lookup()
RH-Author: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: <20210210111518.228148-3-stefanha@redhat.com>
Patchwork-id: 101033
O-Subject: [RHEL-AV-8.4.0 qemu-kvm PATCH 2/3] virtiofsd: optionally return inode pointer from lo_do_lookup()
Bugzilla: 1920740
RH-Acked-by: Laszlo Ersek <lersek@redhat.com>
RH-Acked-by: Greg Kurz <gkurz@redhat.com>
RH-Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
lo_do_lookup() finds an existing inode or allocates a new one. It
increments nlookup so that the inode stays alive until the client
releases it.
Existing callers don't need the struct lo_inode so the function doesn't
return it. Extend the function to optionally return the inode. The next
commit will need it.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20210204150208.367837-3-stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
(cherry picked from commit 22d2ece71e533310da31f2857ebc4a00d91968b3)
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Eduardo Lima (Etrunko) <etrunko@redhat.com>
---
tools/virtiofsd/passthrough_ll.c | 29 +++++++++++++++++++++--------
1 file changed, 21 insertions(+), 8 deletions(-)
diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c
index 218e20e9d7..2bd050b620 100644
--- a/tools/virtiofsd/passthrough_ll.c
+++ b/tools/virtiofsd/passthrough_ll.c
@@ -843,11 +843,13 @@ static int do_statx(struct lo_data *lo, int dirfd, const char *pathname,
}
/*
- * Increments nlookup and caller must release refcount using
- * lo_inode_put(&parent).
+ * Increments nlookup on the inode on success. unref_inode_lolocked() must be
+ * called eventually to decrement nlookup again. If inodep is non-NULL, the
+ * inode pointer is stored and the caller must call lo_inode_put().
*/
static int lo_do_lookup(fuse_req_t req, fuse_ino_t parent, const char *name,
- struct fuse_entry_param *e)
+ struct fuse_entry_param *e,
+ struct lo_inode **inodep)
{
int newfd;
int res;
@@ -857,6 +859,10 @@ static int lo_do_lookup(fuse_req_t req, fuse_ino_t parent, const char *name,
struct lo_inode *inode = NULL;
struct lo_inode *dir = lo_inode(req, parent);
+ if (inodep) {
+ *inodep = NULL;
+ }
+
/*
* name_to_handle_at() and open_by_handle_at() can reach here with fuse
* mount point in guest, but we don't have its inode info in the
@@ -924,7 +930,14 @@ static int lo_do_lookup(fuse_req_t req, fuse_ino_t parent, const char *name,
pthread_mutex_unlock(&lo->mutex);
}
e->ino = inode->fuse_ino;
- lo_inode_put(lo, &inode);
+
+ /* Transfer ownership of inode pointer to caller or drop it */
+ if (inodep) {
+ *inodep = inode;
+ } else {
+ lo_inode_put(lo, &inode);
+ }
+
lo_inode_put(lo, &dir);
fuse_log(FUSE_LOG_DEBUG, " %lli/%s -> %lli\n", (unsigned long long)parent,
@@ -959,7 +972,7 @@ static void lo_lookup(fuse_req_t req, fuse_ino_t parent, const char *name)
return;
}
- err = lo_do_lookup(req, parent, name, &e);
+ err = lo_do_lookup(req, parent, name, &e, NULL);
if (err) {
fuse_reply_err(req, err);
} else {
@@ -1067,7 +1080,7 @@ static void lo_mknod_symlink(fuse_req_t req, fuse_ino_t parent,
goto out;
}
- saverr = lo_do_lookup(req, parent, name, &e);
+ saverr = lo_do_lookup(req, parent, name, &e, NULL);
if (saverr) {
goto out;
}
@@ -1544,7 +1557,7 @@ static void lo_do_readdir(fuse_req_t req, fuse_ino_t ino, size_t size,
if (plus) {
if (!is_dot_or_dotdot(name)) {
- err = lo_do_lookup(req, ino, name, &e);
+ err = lo_do_lookup(req, ino, name, &e, NULL);
if (err) {
goto error;
}
@@ -1742,7 +1755,7 @@ static void lo_create(fuse_req_t req, fuse_ino_t parent, const char *name,
}
fi->fh = fh;
- err = lo_do_lookup(req, parent, name, &e);
+ err = lo_do_lookup(req, parent, name, &e, NULL);
}
if (lo->cache == CACHE_NONE) {
fi->direct_io = 1;
--
2.27.0