nvmet: add ns revalidation support

Add support for detecting capacity changes on nvmet blockdev and file
backed namespaces. This allows for emulating and testing online resizing
of nvme devices and filesystems on top.

Signed-off-by: Anthony Iliopoulos <ailiop@suse.com>
[chaitanya: Fix comments posted on V1]
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
[hch: reuse code a bit more]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 9d6f75cfa77ca2ed2ba8ff733068a5e8f5c48f30..4c79aa804887188aa69ca64dc55fa0deb842a9e1 100644 (file)
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -486,6 +486,11 @@ static void nvmet_execute_identify_ns(struct nvmet_req *req)
        if (!ns)
                goto done;
 
+       if (ns->bdev)
+               nvmet_bdev_ns_revalidate(ns);
+       else
+               nvmet_file_ns_revalidate(ns);
+
        /*
         * nuse = ncap = nsze isn't always true, but we have no way to find
         * that out from the underlying device.

diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c
index ea0e596be15dc5a9c72380cf39dcc8678b88bfe6..0427e040e3dd1beceb3a69c3f2086aadf6cd1b0b 100644 (file)
--- a/drivers/nvme/target/io-cmd-bdev.c
+++ b/drivers/nvme/target/io-cmd-bdev.c
@@ -75,6 +75,11 @@ void nvmet_bdev_ns_disable(struct nvmet_ns *ns)
        }
 }
 
+void nvmet_bdev_ns_revalidate(struct nvmet_ns *ns)
+{
+       ns->size = i_size_read(ns->bdev->bd_inode);
+}
+
 static u16 blk_to_nvme_status(struct nvmet_req *req, blk_status_t blk_sts)
 {
        u16 status = NVME_SC_SUCCESS;

diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c
index cd5670b83118f40786fac018fc3ad21c46c89a23..f0bd08d86ac0bc7116f771e76052affb222c5a7b 100644 (file)
--- a/drivers/nvme/target/io-cmd-file.c
+++ b/drivers/nvme/target/io-cmd-file.c
@@ -13,6 +13,18 @@
 #define NVMET_MAX_MPOOL_BVEC           16
 #define NVMET_MIN_MPOOL_OBJ            16
 
+int 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;
+}
+
 void nvmet_file_ns_disable(struct nvmet_ns *ns)
 {
        if (ns->file) {
@@ -30,7 +42,6 @@ void nvmet_file_ns_disable(struct nvmet_ns *ns)
 int nvmet_file_ns_enable(struct nvmet_ns *ns)
 {
        int flags = O_RDWR | O_LARGEFILE;
-       struct kstat stat;
        int ret;
 
        if (!ns->buffered_io)
@@ -43,12 +54,10 @@ int nvmet_file_ns_enable(struct nvmet_ns *ns)
                return PTR_ERR(ns->file);
        }
 
-       ret = vfs_getattr(&ns->file->f_path,
-                       &stat, STATX_SIZE, AT_STATX_FORCE_SYNC);
+       ret = nvmet_file_ns_revalidate(ns);
        if (ret)
                goto err;
 
-       ns->size = stat.size;
        /*
         * i_blkbits can be greater than the universally accepted upper bound,
         * so make sure we export a sane namespace lba_shift.

diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index 421dff3ea1433e35f4636a37732a5ffbc3a5c884..3d981eb6e100bdd299ceb4da108a58cdec1c8b64 100644 (file)
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -498,6 +498,8 @@ void nvmet_file_ns_disable(struct nvmet_ns *ns);
 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);
 
 static inline u32 nvmet_rw_len(struct nvmet_req *req)
 {