v4.19.13 snapshot.
diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c
new file mode 100644
index 0000000..81a9dc5
--- /dev/null
+++ b/drivers/nvme/target/io-cmd-file.c
@@ -0,0 +1,346 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NVMe Over Fabrics Target File I/O commands implementation.
+ * Copyright (c) 2017-2018 Western Digital Corporation or its
+ * affiliates.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/uio.h>
+#include <linux/falloc.h>
+#include <linux/file.h>
+#include "nvmet.h"
+
+#define NVMET_MAX_MPOOL_BVEC 16
+#define NVMET_MIN_MPOOL_OBJ 16
+
+void nvmet_file_ns_disable(struct nvmet_ns *ns)
+{
+ if (ns->file) {
+ if (ns->buffered_io)
+ flush_workqueue(buffered_io_wq);
+ mempool_destroy(ns->bvec_pool);
+ ns->bvec_pool = NULL;
+ kmem_cache_destroy(ns->bvec_cache);
+ ns->bvec_cache = NULL;
+ fput(ns->file);
+ ns->file = NULL;
+ }
+}
+
+int nvmet_file_ns_enable(struct nvmet_ns *ns)
+{
+ int flags = O_RDWR | O_LARGEFILE;
+ struct kstat stat;
+ int ret;
+
+ if (!ns->buffered_io)
+ flags |= O_DIRECT;
+
+ ns->file = filp_open(ns->device_path, flags, 0);
+ if (IS_ERR(ns->file)) {
+ pr_err("failed to open file %s: (%ld)\n",
+ ns->device_path, PTR_ERR(ns->file));
+ return PTR_ERR(ns->file);
+ }
+
+ ret = vfs_getattr(&ns->file->f_path,
+ &stat, STATX_SIZE, AT_STATX_FORCE_SYNC);
+ if (ret)
+ goto err;
+
+ ns->size = stat.size;
+ ns->blksize_shift = file_inode(ns->file)->i_blkbits;
+
+ ns->bvec_cache = kmem_cache_create("nvmet-bvec",
+ NVMET_MAX_MPOOL_BVEC * sizeof(struct bio_vec),
+ 0, SLAB_HWCACHE_ALIGN, NULL);
+ if (!ns->bvec_cache) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ ns->bvec_pool = mempool_create(NVMET_MIN_MPOOL_OBJ, mempool_alloc_slab,
+ mempool_free_slab, ns->bvec_cache);
+
+ if (!ns->bvec_pool) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ return ret;
+err:
+ ns->size = 0;
+ ns->blksize_shift = 0;
+ nvmet_file_ns_disable(ns);
+ return ret;
+}
+
+static void nvmet_file_init_bvec(struct bio_vec *bv, struct sg_page_iter *iter)
+{
+ bv->bv_page = sg_page_iter_page(iter);
+ bv->bv_offset = iter->sg->offset;
+ bv->bv_len = PAGE_SIZE - iter->sg->offset;
+}
+
+static ssize_t nvmet_file_submit_bvec(struct nvmet_req *req, loff_t pos,
+ unsigned long nr_segs, size_t count)
+{
+ struct kiocb *iocb = &req->f.iocb;
+ ssize_t (*call_iter)(struct kiocb *iocb, struct iov_iter *iter);
+ struct iov_iter iter;
+ int ki_flags = 0, rw;
+ ssize_t ret;
+
+ if (req->cmd->rw.opcode == nvme_cmd_write) {
+ if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA))
+ ki_flags = IOCB_DSYNC;
+ call_iter = req->ns->file->f_op->write_iter;
+ rw = WRITE;
+ } else {
+ call_iter = req->ns->file->f_op->read_iter;
+ rw = READ;
+ }
+
+ iov_iter_bvec(&iter, ITER_BVEC | rw, req->f.bvec, nr_segs, count);
+
+ iocb->ki_pos = pos;
+ iocb->ki_filp = req->ns->file;
+ iocb->ki_flags = ki_flags | iocb_flags(req->ns->file);
+
+ ret = call_iter(iocb, &iter);
+
+ if (ret != -EIOCBQUEUED && iocb->ki_complete)
+ iocb->ki_complete(iocb, ret, 0);
+
+ return ret;
+}
+
+static void nvmet_file_io_done(struct kiocb *iocb, long ret, long ret2)
+{
+ struct nvmet_req *req = container_of(iocb, struct nvmet_req, f.iocb);
+
+ if (req->f.bvec != req->inline_bvec) {
+ if (likely(req->f.mpool_alloc == false))
+ kfree(req->f.bvec);
+ else
+ mempool_free(req->f.bvec, req->ns->bvec_pool);
+ }
+
+ nvmet_req_complete(req, ret != req->data_len ?
+ NVME_SC_INTERNAL | NVME_SC_DNR : 0);
+}
+
+static void nvmet_file_execute_rw(struct nvmet_req *req)
+{
+ ssize_t nr_bvec = DIV_ROUND_UP(req->data_len, PAGE_SIZE);
+ struct sg_page_iter sg_pg_iter;
+ unsigned long bv_cnt = 0;
+ bool is_sync = false;
+ size_t len = 0, total_len = 0;
+ ssize_t ret = 0;
+ loff_t pos;
+
+ if (!req->sg_cnt || !nr_bvec) {
+ nvmet_req_complete(req, 0);
+ return;
+ }
+
+ pos = le64_to_cpu(req->cmd->rw.slba) << req->ns->blksize_shift;
+ if (unlikely(pos + req->data_len > req->ns->size)) {
+ nvmet_req_complete(req, NVME_SC_LBA_RANGE | NVME_SC_DNR);
+ return;
+ }
+
+ if (nr_bvec > NVMET_MAX_INLINE_BIOVEC)
+ req->f.bvec = kmalloc_array(nr_bvec, sizeof(struct bio_vec),
+ GFP_KERNEL);
+ else
+ req->f.bvec = req->inline_bvec;
+
+ req->f.mpool_alloc = false;
+ if (unlikely(!req->f.bvec)) {
+ /* fallback under memory pressure */
+ req->f.bvec = mempool_alloc(req->ns->bvec_pool, GFP_KERNEL);
+ req->f.mpool_alloc = true;
+ if (nr_bvec > NVMET_MAX_MPOOL_BVEC)
+ is_sync = true;
+ }
+
+ memset(&req->f.iocb, 0, sizeof(struct kiocb));
+ for_each_sg_page(req->sg, &sg_pg_iter, req->sg_cnt, 0) {
+ nvmet_file_init_bvec(&req->f.bvec[bv_cnt], &sg_pg_iter);
+ len += req->f.bvec[bv_cnt].bv_len;
+ total_len += req->f.bvec[bv_cnt].bv_len;
+ bv_cnt++;
+
+ WARN_ON_ONCE((nr_bvec - 1) < 0);
+
+ if (unlikely(is_sync) &&
+ (nr_bvec - 1 == 0 || bv_cnt == NVMET_MAX_MPOOL_BVEC)) {
+ ret = nvmet_file_submit_bvec(req, pos, bv_cnt, len);
+ if (ret < 0)
+ goto out;
+ pos += len;
+ bv_cnt = 0;
+ len = 0;
+ }
+ nr_bvec--;
+ }
+
+ if (WARN_ON_ONCE(total_len != req->data_len))
+ ret = -EIO;
+out:
+ if (unlikely(is_sync || ret)) {
+ nvmet_file_io_done(&req->f.iocb, ret < 0 ? ret : total_len, 0);
+ return;
+ }
+ req->f.iocb.ki_complete = nvmet_file_io_done;
+ nvmet_file_submit_bvec(req, pos, bv_cnt, total_len);
+}
+
+static void nvmet_file_buffered_io_work(struct work_struct *w)
+{
+ struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
+
+ nvmet_file_execute_rw(req);
+}
+
+static void nvmet_file_execute_rw_buffered_io(struct nvmet_req *req)
+{
+ INIT_WORK(&req->f.work, nvmet_file_buffered_io_work);
+ queue_work(buffered_io_wq, &req->f.work);
+}
+
+u16 nvmet_file_flush(struct nvmet_req *req)
+{
+ if (vfs_fsync(req->ns->file, 1) < 0)
+ return NVME_SC_INTERNAL | NVME_SC_DNR;
+ return 0;
+}
+
+static void nvmet_file_flush_work(struct work_struct *w)
+{
+ struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
+
+ nvmet_req_complete(req, nvmet_file_flush(req));
+}
+
+static void nvmet_file_execute_flush(struct nvmet_req *req)
+{
+ INIT_WORK(&req->f.work, nvmet_file_flush_work);
+ schedule_work(&req->f.work);
+}
+
+static void nvmet_file_execute_discard(struct nvmet_req *req)
+{
+ int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
+ struct nvme_dsm_range range;
+ loff_t offset, len;
+ u16 ret;
+ int i;
+
+ for (i = 0; i <= le32_to_cpu(req->cmd->dsm.nr); i++) {
+ ret = nvmet_copy_from_sgl(req, i * sizeof(range), &range,
+ sizeof(range));
+ if (ret)
+ break;
+
+ offset = le64_to_cpu(range.slba) << req->ns->blksize_shift;
+ len = le32_to_cpu(range.nlb) << req->ns->blksize_shift;
+ if (offset + len > req->ns->size) {
+ ret = NVME_SC_LBA_RANGE | NVME_SC_DNR;
+ break;
+ }
+
+ if (vfs_fallocate(req->ns->file, mode, offset, len)) {
+ ret = NVME_SC_INTERNAL | NVME_SC_DNR;
+ break;
+ }
+ }
+
+ nvmet_req_complete(req, ret);
+}
+
+static void nvmet_file_dsm_work(struct work_struct *w)
+{
+ struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
+
+ switch (le32_to_cpu(req->cmd->dsm.attributes)) {
+ case NVME_DSMGMT_AD:
+ nvmet_file_execute_discard(req);
+ return;
+ case NVME_DSMGMT_IDR:
+ case NVME_DSMGMT_IDW:
+ default:
+ /* Not supported yet */
+ nvmet_req_complete(req, 0);
+ return;
+ }
+}
+
+static void nvmet_file_execute_dsm(struct nvmet_req *req)
+{
+ INIT_WORK(&req->f.work, nvmet_file_dsm_work);
+ schedule_work(&req->f.work);
+}
+
+static void nvmet_file_write_zeroes_work(struct work_struct *w)
+{
+ struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
+ struct nvme_write_zeroes_cmd *write_zeroes = &req->cmd->write_zeroes;
+ int mode = FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE;
+ loff_t offset;
+ loff_t len;
+ int ret;
+
+ offset = le64_to_cpu(write_zeroes->slba) << req->ns->blksize_shift;
+ len = (((sector_t)le16_to_cpu(write_zeroes->length) + 1) <<
+ req->ns->blksize_shift);
+
+ if (unlikely(offset + len > req->ns->size)) {
+ nvmet_req_complete(req, NVME_SC_LBA_RANGE | NVME_SC_DNR);
+ return;
+ }
+
+ ret = vfs_fallocate(req->ns->file, mode, offset, len);
+ nvmet_req_complete(req, ret < 0 ? NVME_SC_INTERNAL | NVME_SC_DNR : 0);
+}
+
+static void nvmet_file_execute_write_zeroes(struct nvmet_req *req)
+{
+ INIT_WORK(&req->f.work, nvmet_file_write_zeroes_work);
+ schedule_work(&req->f.work);
+}
+
+u16 nvmet_file_parse_io_cmd(struct nvmet_req *req)
+{
+ struct nvme_command *cmd = req->cmd;
+
+ switch (cmd->common.opcode) {
+ case nvme_cmd_read:
+ case nvme_cmd_write:
+ if (req->ns->buffered_io)
+ req->execute = nvmet_file_execute_rw_buffered_io;
+ else
+ req->execute = nvmet_file_execute_rw;
+ req->data_len = nvmet_rw_len(req);
+ return 0;
+ case nvme_cmd_flush:
+ req->execute = nvmet_file_execute_flush;
+ req->data_len = 0;
+ return 0;
+ case nvme_cmd_dsm:
+ req->execute = nvmet_file_execute_dsm;
+ req->data_len = (le32_to_cpu(cmd->dsm.nr) + 1) *
+ sizeof(struct nvme_dsm_range);
+ return 0;
+ case nvme_cmd_write_zeroes:
+ req->execute = nvmet_file_execute_write_zeroes;
+ req->data_len = 0;
+ return 0;
+ default:
+ pr_err("unhandled cmd for file ns %d on qid %d\n",
+ cmd->common.opcode, req->sq->qid);
+ return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
+ }
+}