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-rw-r--r--drivers/target/target_core_file.c961
1 files changed, 961 insertions, 0 deletions
diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c
new file mode 100644
index 000000000..18fbbe510
--- /dev/null
+++ b/drivers/target/target_core_file.c
@@ -0,0 +1,961 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*******************************************************************************
+ * Filename: target_core_file.c
+ *
+ * This file contains the Storage Engine <-> FILEIO transport specific functions
+ *
+ * (c) Copyright 2005-2013 Datera, Inc.
+ *
+ * Nicholas A. Bellinger <nab@kernel.org>
+ *
+ ******************************************************************************/
+
+#include <linux/string.h>
+#include <linux/parser.h>
+#include <linux/timer.h>
+#include <linux/blkdev.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/falloc.h>
+#include <linux/uio.h>
+#include <scsi/scsi_proto.h>
+#include <asm/unaligned.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_backend.h>
+
+#include "target_core_file.h"
+
+static inline struct fd_dev *FD_DEV(struct se_device *dev)
+{
+ return container_of(dev, struct fd_dev, dev);
+}
+
+static int fd_attach_hba(struct se_hba *hba, u32 host_id)
+{
+ struct fd_host *fd_host;
+
+ fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
+ if (!fd_host) {
+ pr_err("Unable to allocate memory for struct fd_host\n");
+ return -ENOMEM;
+ }
+
+ fd_host->fd_host_id = host_id;
+
+ hba->hba_ptr = fd_host;
+
+ pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
+ " Target Core Stack %s\n", hba->hba_id, FD_VERSION,
+ TARGET_CORE_VERSION);
+ pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic\n",
+ hba->hba_id, fd_host->fd_host_id);
+
+ return 0;
+}
+
+static void fd_detach_hba(struct se_hba *hba)
+{
+ struct fd_host *fd_host = hba->hba_ptr;
+
+ pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
+ " Target Core\n", hba->hba_id, fd_host->fd_host_id);
+
+ kfree(fd_host);
+ hba->hba_ptr = NULL;
+}
+
+static struct se_device *fd_alloc_device(struct se_hba *hba, const char *name)
+{
+ struct fd_dev *fd_dev;
+ struct fd_host *fd_host = hba->hba_ptr;
+
+ fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
+ if (!fd_dev) {
+ pr_err("Unable to allocate memory for struct fd_dev\n");
+ return NULL;
+ }
+
+ fd_dev->fd_host = fd_host;
+
+ pr_debug("FILEIO: Allocated fd_dev for %p\n", name);
+
+ return &fd_dev->dev;
+}
+
+static int fd_configure_device(struct se_device *dev)
+{
+ struct fd_dev *fd_dev = FD_DEV(dev);
+ struct fd_host *fd_host = dev->se_hba->hba_ptr;
+ struct file *file;
+ struct inode *inode = NULL;
+ int flags, ret = -EINVAL;
+
+ if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
+ pr_err("Missing fd_dev_name=\n");
+ return -EINVAL;
+ }
+
+ /*
+ * Use O_DSYNC by default instead of O_SYNC to forgo syncing
+ * of pure timestamp updates.
+ */
+ flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
+
+ /*
+ * Optionally allow fd_buffered_io=1 to be enabled for people
+ * who want use the fs buffer cache as an WriteCache mechanism.
+ *
+ * This means that in event of a hard failure, there is a risk
+ * of silent data-loss if the SCSI client has *not* performed a
+ * forced unit access (FUA) write, or issued SYNCHRONIZE_CACHE
+ * to write-out the entire device cache.
+ */
+ if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
+ pr_debug("FILEIO: Disabling O_DSYNC, using buffered FILEIO\n");
+ flags &= ~O_DSYNC;
+ }
+
+ file = filp_open(fd_dev->fd_dev_name, flags, 0600);
+ if (IS_ERR(file)) {
+ pr_err("filp_open(%s) failed\n", fd_dev->fd_dev_name);
+ ret = PTR_ERR(file);
+ goto fail;
+ }
+ fd_dev->fd_file = file;
+ /*
+ * If using a block backend with this struct file, we extract
+ * fd_dev->fd_[block,dev]_size from struct block_device.
+ *
+ * Otherwise, we use the passed fd_size= from configfs
+ */
+ inode = file->f_mapping->host;
+ if (S_ISBLK(inode->i_mode)) {
+ struct request_queue *q = bdev_get_queue(inode->i_bdev);
+ unsigned long long dev_size;
+
+ fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
+ /*
+ * Determine the number of bytes from i_size_read() minus
+ * one (1) logical sector from underlying struct block_device
+ */
+ dev_size = (i_size_read(file->f_mapping->host) -
+ fd_dev->fd_block_size);
+
+ pr_debug("FILEIO: Using size: %llu bytes from struct"
+ " block_device blocks: %llu logical_block_size: %d\n",
+ dev_size, div_u64(dev_size, fd_dev->fd_block_size),
+ fd_dev->fd_block_size);
+
+ if (target_configure_unmap_from_queue(&dev->dev_attrib, q))
+ pr_debug("IFILE: BLOCK Discard support available,"
+ " disabled by default\n");
+ /*
+ * Enable write same emulation for IBLOCK and use 0xFFFF as
+ * the smaller WRITE_SAME(10) only has a two-byte block count.
+ */
+ dev->dev_attrib.max_write_same_len = 0xFFFF;
+
+ if (blk_queue_nonrot(q))
+ dev->dev_attrib.is_nonrot = 1;
+ } else {
+ if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
+ pr_err("FILEIO: Missing fd_dev_size="
+ " parameter, and no backing struct"
+ " block_device\n");
+ goto fail;
+ }
+
+ fd_dev->fd_block_size = FD_BLOCKSIZE;
+ /*
+ * Limit UNMAP emulation to 8k Number of LBAs (NoLB)
+ */
+ dev->dev_attrib.max_unmap_lba_count = 0x2000;
+ /*
+ * Currently hardcoded to 1 in Linux/SCSI code..
+ */
+ dev->dev_attrib.max_unmap_block_desc_count = 1;
+ dev->dev_attrib.unmap_granularity = 1;
+ dev->dev_attrib.unmap_granularity_alignment = 0;
+
+ /*
+ * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB)
+ * based upon struct iovec limit for vfs_writev()
+ */
+ dev->dev_attrib.max_write_same_len = 0x1000;
+ }
+
+ dev->dev_attrib.hw_block_size = fd_dev->fd_block_size;
+ dev->dev_attrib.max_bytes_per_io = FD_MAX_BYTES;
+ dev->dev_attrib.hw_max_sectors = FD_MAX_BYTES / fd_dev->fd_block_size;
+ dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
+
+ if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
+ pr_debug("FILEIO: Forcing setting of emulate_write_cache=1"
+ " with FDBD_HAS_BUFFERED_IO_WCE\n");
+ dev->dev_attrib.emulate_write_cache = 1;
+ }
+
+ fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
+ fd_dev->fd_queue_depth = dev->queue_depth;
+
+ pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
+ " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
+ fd_dev->fd_dev_name, fd_dev->fd_dev_size);
+
+ return 0;
+fail:
+ if (fd_dev->fd_file) {
+ filp_close(fd_dev->fd_file, NULL);
+ fd_dev->fd_file = NULL;
+ }
+ return ret;
+}
+
+static void fd_dev_call_rcu(struct rcu_head *p)
+{
+ struct se_device *dev = container_of(p, struct se_device, rcu_head);
+ struct fd_dev *fd_dev = FD_DEV(dev);
+
+ kfree(fd_dev);
+}
+
+static void fd_free_device(struct se_device *dev)
+{
+ call_rcu(&dev->rcu_head, fd_dev_call_rcu);
+}
+
+static void fd_destroy_device(struct se_device *dev)
+{
+ struct fd_dev *fd_dev = FD_DEV(dev);
+
+ if (fd_dev->fd_file) {
+ filp_close(fd_dev->fd_file, NULL);
+ fd_dev->fd_file = NULL;
+ }
+}
+
+struct target_core_file_cmd {
+ unsigned long len;
+ struct se_cmd *cmd;
+ struct kiocb iocb;
+};
+
+static void cmd_rw_aio_complete(struct kiocb *iocb, long ret, long ret2)
+{
+ struct target_core_file_cmd *cmd;
+
+ cmd = container_of(iocb, struct target_core_file_cmd, iocb);
+
+ if (ret != cmd->len)
+ target_complete_cmd(cmd->cmd, SAM_STAT_CHECK_CONDITION);
+ else
+ target_complete_cmd(cmd->cmd, SAM_STAT_GOOD);
+
+ kfree(cmd);
+}
+
+static sense_reason_t
+fd_execute_rw_aio(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
+ enum dma_data_direction data_direction)
+{
+ int is_write = !(data_direction == DMA_FROM_DEVICE);
+ struct se_device *dev = cmd->se_dev;
+ struct fd_dev *fd_dev = FD_DEV(dev);
+ struct file *file = fd_dev->fd_file;
+ struct target_core_file_cmd *aio_cmd;
+ struct iov_iter iter = {};
+ struct scatterlist *sg;
+ struct bio_vec *bvec;
+ ssize_t len = 0;
+ int ret = 0, i;
+
+ aio_cmd = kmalloc(sizeof(struct target_core_file_cmd), GFP_KERNEL);
+ if (!aio_cmd)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+ bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
+ if (!bvec) {
+ kfree(aio_cmd);
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+
+ for_each_sg(sgl, sg, sgl_nents, i) {
+ bvec[i].bv_page = sg_page(sg);
+ bvec[i].bv_len = sg->length;
+ bvec[i].bv_offset = sg->offset;
+
+ len += sg->length;
+ }
+
+ iov_iter_bvec(&iter, is_write, bvec, sgl_nents, len);
+
+ aio_cmd->cmd = cmd;
+ aio_cmd->len = len;
+ aio_cmd->iocb.ki_pos = cmd->t_task_lba * dev->dev_attrib.block_size;
+ aio_cmd->iocb.ki_filp = file;
+ aio_cmd->iocb.ki_complete = cmd_rw_aio_complete;
+ aio_cmd->iocb.ki_flags = IOCB_DIRECT;
+
+ if (is_write && (cmd->se_cmd_flags & SCF_FUA))
+ aio_cmd->iocb.ki_flags |= IOCB_DSYNC;
+
+ if (is_write)
+ ret = call_write_iter(file, &aio_cmd->iocb, &iter);
+ else
+ ret = call_read_iter(file, &aio_cmd->iocb, &iter);
+
+ kfree(bvec);
+
+ if (ret != -EIOCBQUEUED)
+ cmd_rw_aio_complete(&aio_cmd->iocb, ret, 0);
+
+ return 0;
+}
+
+static int fd_do_rw(struct se_cmd *cmd, struct file *fd,
+ u32 block_size, struct scatterlist *sgl,
+ u32 sgl_nents, u32 data_length, int is_write)
+{
+ struct scatterlist *sg;
+ struct iov_iter iter;
+ struct bio_vec *bvec;
+ ssize_t len = 0;
+ loff_t pos = (cmd->t_task_lba * block_size);
+ int ret = 0, i;
+
+ bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
+ if (!bvec) {
+ pr_err("Unable to allocate fd_do_readv iov[]\n");
+ return -ENOMEM;
+ }
+
+ for_each_sg(sgl, sg, sgl_nents, i) {
+ bvec[i].bv_page = sg_page(sg);
+ bvec[i].bv_len = sg->length;
+ bvec[i].bv_offset = sg->offset;
+
+ len += sg->length;
+ }
+
+ iov_iter_bvec(&iter, is_write, bvec, sgl_nents, len);
+ if (is_write)
+ ret = vfs_iter_write(fd, &iter, &pos, 0);
+ else
+ ret = vfs_iter_read(fd, &iter, &pos, 0);
+
+ if (is_write) {
+ if (ret < 0 || ret != data_length) {
+ pr_err("%s() write returned %d\n", __func__, ret);
+ if (ret >= 0)
+ ret = -EINVAL;
+ }
+ } else {
+ /*
+ * Return zeros and GOOD status even if the READ did not return
+ * the expected virt_size for struct file w/o a backing struct
+ * block_device.
+ */
+ if (S_ISBLK(file_inode(fd)->i_mode)) {
+ if (ret < 0 || ret != data_length) {
+ pr_err("%s() returned %d, expecting %u for "
+ "S_ISBLK\n", __func__, ret,
+ data_length);
+ if (ret >= 0)
+ ret = -EINVAL;
+ }
+ } else {
+ if (ret < 0) {
+ pr_err("%s() returned %d for non S_ISBLK\n",
+ __func__, ret);
+ } else if (ret != data_length) {
+ /*
+ * Short read case:
+ * Probably some one truncate file under us.
+ * We must explicitly zero sg-pages to prevent
+ * expose uninizialized pages to userspace.
+ */
+ if (ret < data_length)
+ ret += iov_iter_zero(data_length - ret, &iter);
+ else
+ ret = -EINVAL;
+ }
+ }
+ }
+ kfree(bvec);
+ return ret;
+}
+
+static sense_reason_t
+fd_execute_sync_cache(struct se_cmd *cmd)
+{
+ struct se_device *dev = cmd->se_dev;
+ struct fd_dev *fd_dev = FD_DEV(dev);
+ int immed = (cmd->t_task_cdb[1] & 0x2);
+ loff_t start, end;
+ int ret;
+
+ /*
+ * If the Immediate bit is set, queue up the GOOD response
+ * for this SYNCHRONIZE_CACHE op
+ */
+ if (immed)
+ target_complete_cmd(cmd, SAM_STAT_GOOD);
+
+ /*
+ * Determine if we will be flushing the entire device.
+ */
+ if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
+ start = 0;
+ end = LLONG_MAX;
+ } else {
+ start = cmd->t_task_lba * dev->dev_attrib.block_size;
+ if (cmd->data_length)
+ end = start + cmd->data_length - 1;
+ else
+ end = LLONG_MAX;
+ }
+
+ ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
+ if (ret != 0)
+ pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
+
+ if (immed)
+ return 0;
+
+ if (ret)
+ target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
+ else
+ target_complete_cmd(cmd, SAM_STAT_GOOD);
+
+ return 0;
+}
+
+static sense_reason_t
+fd_execute_write_same(struct se_cmd *cmd)
+{
+ struct se_device *se_dev = cmd->se_dev;
+ struct fd_dev *fd_dev = FD_DEV(se_dev);
+ loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
+ sector_t nolb = sbc_get_write_same_sectors(cmd);
+ struct iov_iter iter;
+ struct bio_vec *bvec;
+ unsigned int len = 0, i;
+ ssize_t ret;
+
+ if (!nolb) {
+ target_complete_cmd(cmd, SAM_STAT_GOOD);
+ return 0;
+ }
+ if (cmd->prot_op) {
+ pr_err("WRITE_SAME: Protection information with FILEIO"
+ " backends not supported\n");
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+
+ if (cmd->t_data_nents > 1 ||
+ cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
+ pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
+ " block_size: %u\n",
+ cmd->t_data_nents,
+ cmd->t_data_sg[0].length,
+ cmd->se_dev->dev_attrib.block_size);
+ return TCM_INVALID_CDB_FIELD;
+ }
+
+ bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
+ if (!bvec)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+ for (i = 0; i < nolb; i++) {
+ bvec[i].bv_page = sg_page(&cmd->t_data_sg[0]);
+ bvec[i].bv_len = cmd->t_data_sg[0].length;
+ bvec[i].bv_offset = cmd->t_data_sg[0].offset;
+
+ len += se_dev->dev_attrib.block_size;
+ }
+
+ iov_iter_bvec(&iter, WRITE, bvec, nolb, len);
+ ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos, 0);
+
+ kfree(bvec);
+ if (ret < 0 || ret != len) {
+ pr_err("vfs_iter_write() returned %zd for write same\n", ret);
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+
+ target_complete_cmd(cmd, SAM_STAT_GOOD);
+ return 0;
+}
+
+static int
+fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
+ void *buf, size_t bufsize)
+{
+ struct fd_dev *fd_dev = FD_DEV(se_dev);
+ struct file *prot_fd = fd_dev->fd_prot_file;
+ sector_t prot_length, prot;
+ loff_t pos = lba * se_dev->prot_length;
+
+ if (!prot_fd) {
+ pr_err("Unable to locate fd_dev->fd_prot_file\n");
+ return -ENODEV;
+ }
+
+ prot_length = nolb * se_dev->prot_length;
+
+ for (prot = 0; prot < prot_length;) {
+ sector_t len = min_t(sector_t, bufsize, prot_length - prot);
+ ssize_t ret = kernel_write(prot_fd, buf, len, &pos);
+
+ if (ret != len) {
+ pr_err("vfs_write to prot file failed: %zd\n", ret);
+ return ret < 0 ? ret : -ENODEV;
+ }
+ prot += ret;
+ }
+
+ return 0;
+}
+
+static int
+fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
+{
+ void *buf;
+ int rc;
+
+ buf = (void *)__get_free_page(GFP_KERNEL);
+ if (!buf) {
+ pr_err("Unable to allocate FILEIO prot buf\n");
+ return -ENOMEM;
+ }
+ memset(buf, 0xff, PAGE_SIZE);
+
+ rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
+
+ free_page((unsigned long)buf);
+
+ return rc;
+}
+
+static sense_reason_t
+fd_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
+{
+ struct file *file = FD_DEV(cmd->se_dev)->fd_file;
+ struct inode *inode = file->f_mapping->host;
+ int ret;
+
+ if (!nolb) {
+ return 0;
+ }
+
+ if (cmd->se_dev->dev_attrib.pi_prot_type) {
+ ret = fd_do_prot_unmap(cmd, lba, nolb);
+ if (ret)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+
+ if (S_ISBLK(inode->i_mode)) {
+ /* The backend is block device, use discard */
+ struct block_device *bdev = inode->i_bdev;
+ struct se_device *dev = cmd->se_dev;
+
+ ret = blkdev_issue_discard(bdev,
+ target_to_linux_sector(dev, lba),
+ target_to_linux_sector(dev, nolb),
+ GFP_KERNEL, 0);
+ if (ret < 0) {
+ pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
+ ret);
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+ } else {
+ /* The backend is normal file, use fallocate */
+ struct se_device *se_dev = cmd->se_dev;
+ loff_t pos = lba * se_dev->dev_attrib.block_size;
+ unsigned int len = nolb * se_dev->dev_attrib.block_size;
+ int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
+
+ if (!file->f_op->fallocate)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+ ret = file->f_op->fallocate(file, mode, pos, len);
+ if (ret < 0) {
+ pr_warn("FILEIO: fallocate() failed: %d\n", ret);
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+ }
+
+ return 0;
+}
+
+static sense_reason_t
+fd_execute_rw_buffered(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
+ enum dma_data_direction data_direction)
+{
+ struct se_device *dev = cmd->se_dev;
+ struct fd_dev *fd_dev = FD_DEV(dev);
+ struct file *file = fd_dev->fd_file;
+ struct file *pfile = fd_dev->fd_prot_file;
+ sense_reason_t rc;
+ int ret = 0;
+ /*
+ * Call vectorized fileio functions to map struct scatterlist
+ * physical memory addresses to struct iovec virtual memory.
+ */
+ if (data_direction == DMA_FROM_DEVICE) {
+ if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
+ ret = fd_do_rw(cmd, pfile, dev->prot_length,
+ cmd->t_prot_sg, cmd->t_prot_nents,
+ cmd->prot_length, 0);
+ if (ret < 0)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+
+ ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
+ sgl, sgl_nents, cmd->data_length, 0);
+
+ if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type &&
+ dev->dev_attrib.pi_prot_verify) {
+ u32 sectors = cmd->data_length >>
+ ilog2(dev->dev_attrib.block_size);
+
+ rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
+ 0, cmd->t_prot_sg, 0);
+ if (rc)
+ return rc;
+ }
+ } else {
+ if (cmd->prot_type && dev->dev_attrib.pi_prot_type &&
+ dev->dev_attrib.pi_prot_verify) {
+ u32 sectors = cmd->data_length >>
+ ilog2(dev->dev_attrib.block_size);
+
+ rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
+ 0, cmd->t_prot_sg, 0);
+ if (rc)
+ return rc;
+ }
+
+ ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
+ sgl, sgl_nents, cmd->data_length, 1);
+ /*
+ * Perform implicit vfs_fsync_range() for fd_do_writev() ops
+ * for SCSI WRITEs with Forced Unit Access (FUA) set.
+ * Allow this to happen independent of WCE=0 setting.
+ */
+ if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) {
+ loff_t start = cmd->t_task_lba *
+ dev->dev_attrib.block_size;
+ loff_t end;
+
+ if (cmd->data_length)
+ end = start + cmd->data_length - 1;
+ else
+ end = LLONG_MAX;
+
+ vfs_fsync_range(fd_dev->fd_file, start, end, 1);
+ }
+
+ if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
+ ret = fd_do_rw(cmd, pfile, dev->prot_length,
+ cmd->t_prot_sg, cmd->t_prot_nents,
+ cmd->prot_length, 1);
+ if (ret < 0)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+ }
+
+ if (ret < 0)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+ target_complete_cmd(cmd, SAM_STAT_GOOD);
+ return 0;
+}
+
+static sense_reason_t
+fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
+ enum dma_data_direction data_direction)
+{
+ struct se_device *dev = cmd->se_dev;
+ struct fd_dev *fd_dev = FD_DEV(dev);
+
+ /*
+ * We are currently limited by the number of iovecs (2048) per
+ * single vfs_[writev,readv] call.
+ */
+ if (cmd->data_length > FD_MAX_BYTES) {
+ pr_err("FILEIO: Not able to process I/O of %u bytes due to"
+ "FD_MAX_BYTES: %u iovec count limitation\n",
+ cmd->data_length, FD_MAX_BYTES);
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+
+ if (fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO)
+ return fd_execute_rw_aio(cmd, sgl, sgl_nents, data_direction);
+ return fd_execute_rw_buffered(cmd, sgl, sgl_nents, data_direction);
+}
+
+enum {
+ Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io,
+ Opt_fd_async_io, Opt_err
+};
+
+static match_table_t tokens = {
+ {Opt_fd_dev_name, "fd_dev_name=%s"},
+ {Opt_fd_dev_size, "fd_dev_size=%s"},
+ {Opt_fd_buffered_io, "fd_buffered_io=%d"},
+ {Opt_fd_async_io, "fd_async_io=%d"},
+ {Opt_err, NULL}
+};
+
+static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
+ const char *page, ssize_t count)
+{
+ struct fd_dev *fd_dev = FD_DEV(dev);
+ char *orig, *ptr, *arg_p, *opts;
+ substring_t args[MAX_OPT_ARGS];
+ int ret = 0, arg, token;
+
+ opts = kstrdup(page, GFP_KERNEL);
+ if (!opts)
+ return -ENOMEM;
+
+ orig = opts;
+
+ while ((ptr = strsep(&opts, ",\n")) != NULL) {
+ if (!*ptr)
+ continue;
+
+ token = match_token(ptr, tokens, args);
+ switch (token) {
+ case Opt_fd_dev_name:
+ if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
+ FD_MAX_DEV_NAME) == 0) {
+ ret = -EINVAL;
+ break;
+ }
+ pr_debug("FILEIO: Referencing Path: %s\n",
+ fd_dev->fd_dev_name);
+ fd_dev->fbd_flags |= FBDF_HAS_PATH;
+ break;
+ case Opt_fd_dev_size:
+ arg_p = match_strdup(&args[0]);
+ if (!arg_p) {
+ ret = -ENOMEM;
+ break;
+ }
+ ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
+ kfree(arg_p);
+ if (ret < 0) {
+ pr_err("kstrtoull() failed for"
+ " fd_dev_size=\n");
+ goto out;
+ }
+ pr_debug("FILEIO: Referencing Size: %llu"
+ " bytes\n", fd_dev->fd_dev_size);
+ fd_dev->fbd_flags |= FBDF_HAS_SIZE;
+ break;
+ case Opt_fd_buffered_io:
+ ret = match_int(args, &arg);
+ if (ret)
+ goto out;
+ if (arg != 1) {
+ pr_err("bogus fd_buffered_io=%d value\n", arg);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ pr_debug("FILEIO: Using buffered I/O"
+ " operations for struct fd_dev\n");
+
+ fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
+ break;
+ case Opt_fd_async_io:
+ ret = match_int(args, &arg);
+ if (ret)
+ goto out;
+ if (arg != 1) {
+ pr_err("bogus fd_async_io=%d value\n", arg);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ pr_debug("FILEIO: Using async I/O"
+ " operations for struct fd_dev\n");
+
+ fd_dev->fbd_flags |= FDBD_HAS_ASYNC_IO;
+ break;
+ default:
+ break;
+ }
+ }
+
+out:
+ kfree(orig);
+ return (!ret) ? count : ret;
+}
+
+static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
+{
+ struct fd_dev *fd_dev = FD_DEV(dev);
+ ssize_t bl = 0;
+
+ bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
+ bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s Async: %d\n",
+ fd_dev->fd_dev_name, fd_dev->fd_dev_size,
+ (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
+ "Buffered-WCE" : "O_DSYNC",
+ !!(fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO));
+ return bl;
+}
+
+static sector_t fd_get_blocks(struct se_device *dev)
+{
+ struct fd_dev *fd_dev = FD_DEV(dev);
+ struct file *f = fd_dev->fd_file;
+ struct inode *i = f->f_mapping->host;
+ unsigned long long dev_size;
+ /*
+ * When using a file that references an underlying struct block_device,
+ * ensure dev_size is always based on the current inode size in order
+ * to handle underlying block_device resize operations.
+ */
+ if (S_ISBLK(i->i_mode))
+ dev_size = i_size_read(i);
+ else
+ dev_size = fd_dev->fd_dev_size;
+
+ return div_u64(dev_size - dev->dev_attrib.block_size,
+ dev->dev_attrib.block_size);
+}
+
+static int fd_init_prot(struct se_device *dev)
+{
+ struct fd_dev *fd_dev = FD_DEV(dev);
+ struct file *prot_file, *file = fd_dev->fd_file;
+ struct inode *inode;
+ int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
+ char buf[FD_MAX_DEV_PROT_NAME];
+
+ if (!file) {
+ pr_err("Unable to locate fd_dev->fd_file\n");
+ return -ENODEV;
+ }
+
+ inode = file->f_mapping->host;
+ if (S_ISBLK(inode->i_mode)) {
+ pr_err("FILEIO Protection emulation only supported on"
+ " !S_ISBLK\n");
+ return -ENOSYS;
+ }
+
+ if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
+ flags &= ~O_DSYNC;
+
+ snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
+ fd_dev->fd_dev_name);
+
+ prot_file = filp_open(buf, flags, 0600);
+ if (IS_ERR(prot_file)) {
+ pr_err("filp_open(%s) failed\n", buf);
+ ret = PTR_ERR(prot_file);
+ return ret;
+ }
+ fd_dev->fd_prot_file = prot_file;
+
+ return 0;
+}
+
+static int fd_format_prot(struct se_device *dev)
+{
+ unsigned char *buf;
+ int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
+ int ret;
+
+ if (!dev->dev_attrib.pi_prot_type) {
+ pr_err("Unable to format_prot while pi_prot_type == 0\n");
+ return -ENODEV;
+ }
+
+ buf = vzalloc(unit_size);
+ if (!buf) {
+ pr_err("Unable to allocate FILEIO prot buf\n");
+ return -ENOMEM;
+ }
+
+ pr_debug("Using FILEIO prot_length: %llu\n",
+ (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
+ dev->prot_length);
+
+ memset(buf, 0xff, unit_size);
+ ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
+ buf, unit_size);
+ vfree(buf);
+ return ret;
+}
+
+static void fd_free_prot(struct se_device *dev)
+{
+ struct fd_dev *fd_dev = FD_DEV(dev);
+
+ if (!fd_dev->fd_prot_file)
+ return;
+
+ filp_close(fd_dev->fd_prot_file, NULL);
+ fd_dev->fd_prot_file = NULL;
+}
+
+static struct sbc_ops fd_sbc_ops = {
+ .execute_rw = fd_execute_rw,
+ .execute_sync_cache = fd_execute_sync_cache,
+ .execute_write_same = fd_execute_write_same,
+ .execute_unmap = fd_execute_unmap,
+};
+
+static sense_reason_t
+fd_parse_cdb(struct se_cmd *cmd)
+{
+ return sbc_parse_cdb(cmd, &fd_sbc_ops);
+}
+
+static const struct target_backend_ops fileio_ops = {
+ .name = "fileio",
+ .inquiry_prod = "FILEIO",
+ .inquiry_rev = FD_VERSION,
+ .owner = THIS_MODULE,
+ .attach_hba = fd_attach_hba,
+ .detach_hba = fd_detach_hba,
+ .alloc_device = fd_alloc_device,
+ .configure_device = fd_configure_device,
+ .destroy_device = fd_destroy_device,
+ .free_device = fd_free_device,
+ .parse_cdb = fd_parse_cdb,
+ .set_configfs_dev_params = fd_set_configfs_dev_params,
+ .show_configfs_dev_params = fd_show_configfs_dev_params,
+ .get_device_type = sbc_get_device_type,
+ .get_blocks = fd_get_blocks,
+ .init_prot = fd_init_prot,
+ .format_prot = fd_format_prot,
+ .free_prot = fd_free_prot,
+ .tb_dev_attrib_attrs = sbc_attrib_attrs,
+};
+
+static int __init fileio_module_init(void)
+{
+ return transport_backend_register(&fileio_ops);
+}
+
+static void __exit fileio_module_exit(void)
+{
+ target_backend_unregister(&fileio_ops);
+}
+
+MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
+MODULE_AUTHOR("nab@Linux-iSCSI.org");
+MODULE_LICENSE("GPL");
+
+module_init(fileio_module_init);
+module_exit(fileio_module_exit);