Patch "nvmet: use i_size_read() to set size for file-ns" has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    nvmet: use i_size_read() to set size for file-ns

to the 5.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     nvmet-use-i_size_read-to-set-size-for-file-ns.patch
and it can be found in the queue-5.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 15600ec4dec5e820c78b7067c9b7d88f7b4e65b7
Author: Chaitanya Kulkarni <kch@xxxxxxxxxx>
Date:   Wed Feb 2 01:04:44 2022 -0800

    nvmet: use i_size_read() to set size for file-ns
    
    [ Upstream commit 2caecd62ea5160803b25d96cb1a14ce755c2c259 ]
    
    Instead of calling vfs_getattr() use i_size_read() to read the size of
    file so we can read the size of not only file type but also block type
    with one call. This is needed to implement buffered_io support for the
    NVMeOF block device backend.
    
    We also change return type of function nvmet_file_ns_revalidate() from
    int to void, since this function does not return any meaning value.
    
    Signed-off-by: Chaitanya Kulkarni <kch@xxxxxxxxxx>
    Signed-off-by: Christoph Hellwig <hch@xxxxxx>
    Stable-dep-of: ab76e7206b67 ("nvmet: fix error handling in nvmet_execute_identify_cns_cs_ns()")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c
index eadba13b276de..098b6bf12cd0a 100644
--- a/drivers/nvme/target/io-cmd-file.c
+++ b/drivers/nvme/target/io-cmd-file.c
@@ -13,16 +13,9 @@
 
 #define NVMET_MIN_MPOOL_OBJ		16
 
-int nvmet_file_ns_revalidate(struct nvmet_ns *ns)
+void nvmet_file_ns_revalidate(struct nvmet_ns *ns)
 {
-	struct kstat stat;
-	int ret;
-
-	ret = vfs_getattr(&ns->file->f_path, &stat, STATX_SIZE,
-			  AT_STATX_FORCE_SYNC);
-	if (!ret)
-		ns->size = stat.size;
-	return ret;
+	ns->size = i_size_read(ns->file->f_mapping->host);
 }
 
 void nvmet_file_ns_disable(struct nvmet_ns *ns)
@@ -40,7 +33,7 @@ void nvmet_file_ns_disable(struct nvmet_ns *ns)
 int nvmet_file_ns_enable(struct nvmet_ns *ns)
 {
 	int flags = O_RDWR | O_LARGEFILE;
-	int ret;
+	int ret = 0;
 
 	if (!ns->buffered_io)
 		flags |= O_DIRECT;
@@ -54,9 +47,7 @@ int nvmet_file_ns_enable(struct nvmet_ns *ns)
 		return ret;
 	}
 
-	ret = nvmet_file_ns_revalidate(ns);
-	if (ret)
-		goto err;
+	nvmet_file_ns_revalidate(ns);
 
 	/*
 	 * i_blkbits can be greater than the universally accepted upper bound,
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index fdb06a9d430d2..f3e42d2c85c6c 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -542,7 +542,7 @@ u16 nvmet_bdev_flush(struct nvmet_req *req);
 u16 nvmet_file_flush(struct nvmet_req *req);
 void nvmet_ns_changed(struct nvmet_subsys *subsys, u32 nsid);
 void nvmet_bdev_ns_revalidate(struct nvmet_ns *ns);
-int nvmet_file_ns_revalidate(struct nvmet_ns *ns);
+void nvmet_file_ns_revalidate(struct nvmet_ns *ns);
 void nvmet_ns_revalidate(struct nvmet_ns *ns);
 u16 blk_to_nvme_status(struct nvmet_req *req, blk_status_t blk_sts);