diff options
Diffstat (limited to 'drivers/target/target_core_file.c')
| -rw-r--r-- | drivers/target/target_core_file.c | 961 |
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..8d74e97c9 --- /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 <linux/scatterlist.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 bool fd_configure_unmap(struct se_device *dev) +{ + struct file *file = FD_DEV(dev)->fd_file; + struct inode *inode = file->f_mapping->host; + + if (S_ISBLK(inode->i_mode)) + return target_configure_unmap_from_queue(&dev->dev_attrib, + I_BDEV(inode)); + + /* 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; + return true; +} + +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 block_device *bdev = I_BDEV(inode); + unsigned long long dev_size; + + fd_dev->fd_block_size = bdev_logical_block_size(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); + /* + * 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 (bdev_nonrot(bdev)) + 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 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; + struct bio_vec bvecs[]; +}; + +static void cmd_rw_aio_complete(struct kiocb *iocb, long ret) +{ + 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; + ssize_t len = 0; + int ret = 0, i; + + aio_cmd = kmalloc(struct_size(aio_cmd, bvecs, sgl_nents), GFP_KERNEL); + if (!aio_cmd) + return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + + for_each_sg(sgl, sg, sgl_nents, i) { + aio_cmd->bvecs[i].bv_page = sg_page(sg); + aio_cmd->bvecs[i].bv_len = sg->length; + aio_cmd->bvecs[i].bv_offset = sg->offset; + + len += sg->length; + } + + iov_iter_bvec(&iter, is_write, aio_cmd->bvecs, 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); + + if (ret != -EIOCBQUEUED) + cmd_rw_aio_complete(&aio_cmd->iocb, ret); + + 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) { + file_start_write(fd); + ret = vfs_iter_write(fd, &iter, &pos, 0); + file_end_write(fd); + } 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 (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) + return TCM_INVALID_CDB_FIELD; + + 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, ITER_SOURCE, bvec, nolb, len); + file_start_write(fd_dev->fd_file); + ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos, 0); + file_end_write(fd_dev->fd_file); + + 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; + + memset(buf, 0xff, bufsize); + 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; + } + + 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 = I_BDEV(inode); + 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); + 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); + + 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, + .configure_unmap = fd_configure_unmap, + .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); |