/******************************************************************************* * Filename: target_core_file.c * * This file contains the Storage Engine <-> FILEIO transport specific functions * * (c) Copyright 2005-2012 RisingTide Systems LLC. * * Nicholas A. Bellinger <nab@kernel.org> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * ******************************************************************************/ #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/falloc.h> #include <scsi/scsi.h> #include <scsi/scsi_host.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); } /* fd_attach_hba(): (Part of se_subsystem_api_t template) * * */ 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_MOD_VERSION); pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic" " MaxSectors: %u\n", hba->hba_id, fd_host->fd_host_id, FD_MAX_SECTORS); 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); /* * Check if the underlying struct block_device request_queue supports * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM * in ATA and we need to set TPE=1 */ if (blk_queue_discard(q)) { dev->dev_attrib.max_unmap_lba_count = q->limits.max_discard_sectors; /* * Currently hardcoded to 1 in Linux/SCSI code.. */ dev->dev_attrib.max_unmap_block_desc_count = 1; dev->dev_attrib.unmap_granularity = q->limits.discard_granularity >> 9; dev->dev_attrib.unmap_granularity_alignment = q->limits.discard_alignment; 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.hw_max_sectors = FD_MAX_SECTORS; 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_free_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; } kfree(fd_dev); } static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, int is_write) { struct se_device *se_dev = cmd->se_dev; struct fd_dev *dev = FD_DEV(se_dev); struct file *fd = dev->fd_file; struct scatterlist *sg; struct iovec *iov; mm_segment_t old_fs; loff_t pos = (cmd->t_task_lba * se_dev->dev_attrib.block_size); int ret = 0, i; iov = kzalloc(sizeof(struct iovec) * sgl_nents, GFP_KERNEL); if (!iov) { pr_err("Unable to allocate fd_do_readv iov[]\n"); return -ENOMEM; } for_each_sg(sgl, sg, sgl_nents, i) { iov[i].iov_len = sg->length; iov[i].iov_base = kmap(sg_page(sg)) + sg->offset; } old_fs = get_fs(); set_fs(get_ds()); if (is_write) ret = vfs_writev(fd, &iov[0], sgl_nents, &pos); else ret = vfs_readv(fd, &iov[0], sgl_nents, &pos); set_fs(old_fs); for_each_sg(sgl, sg, sgl_nents, i) kunmap(sg_page(sg)); kfree(iov); if (is_write) { if (ret < 0 || ret != cmd->data_length) { pr_err("%s() write returned %d\n", __func__, ret); return (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 != cmd->data_length) { pr_err("%s() returned %d, expecting %u for " "S_ISBLK\n", __func__, ret, cmd->data_length); return (ret < 0 ? ret : -EINVAL); } } else { if (ret < 0) { pr_err("%s() returned %d for non S_ISBLK\n", __func__, ret); return ret; } } } return 1; } 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; 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 unsigned char * fd_setup_write_same_buf(struct se_cmd *cmd, struct scatterlist *sg, unsigned int len) { struct se_device *se_dev = cmd->se_dev; unsigned int block_size = se_dev->dev_attrib.block_size; unsigned int i = 0, end; unsigned char *buf, *p, *kmap_buf; buf = kzalloc(min_t(unsigned int, len, PAGE_SIZE), GFP_KERNEL); if (!buf) { pr_err("Unable to allocate fd_execute_write_same buf\n"); return NULL; } kmap_buf = kmap(sg_page(sg)) + sg->offset; if (!kmap_buf) { pr_err("kmap() failed in fd_setup_write_same\n"); kfree(buf); return NULL; } /* * Fill local *buf to contain multiple WRITE_SAME blocks up to * min(len, PAGE_SIZE) */ p = buf; end = min_t(unsigned int, len, PAGE_SIZE); while (i < end) { memcpy(p, kmap_buf, block_size); i += block_size; p += block_size; } kunmap(sg_page(sg)); return buf; } 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); struct file *f = fd_dev->fd_file; struct scatterlist *sg; struct iovec *iov; mm_segment_t old_fs; sector_t nolb = sbc_get_write_same_sectors(cmd); loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size; unsigned int len, len_tmp, iov_num; int i, rc; unsigned char *buf; if (!nolb) { target_complete_cmd(cmd, SAM_STAT_GOOD); return 0; } sg = &cmd->t_data_sg[0]; if (cmd->t_data_nents > 1 || sg->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, sg->length, cmd->se_dev->dev_attrib.block_size); return TCM_INVALID_CDB_FIELD; } len = len_tmp = nolb * se_dev->dev_attrib.block_size; iov_num = DIV_ROUND_UP(len, PAGE_SIZE); buf = fd_setup_write_same_buf(cmd, sg, len); if (!buf) return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; iov = vzalloc(sizeof(struct iovec) * iov_num); if (!iov) { pr_err("Unable to allocate fd_execute_write_same iovecs\n"); kfree(buf); return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } /* * Map the single fabric received scatterlist block now populated * in *buf into each iovec for I/O submission. */ for (i = 0; i < iov_num; i++) { iov[i].iov_base = buf; iov[i].iov_len = min_t(unsigned int, len_tmp, PAGE_SIZE); len_tmp -= iov[i].iov_len; } old_fs = get_fs(); set_fs(get_ds()); rc = vfs_writev(f, &iov[0], iov_num, &pos); set_fs(old_fs); vfree(iov); kfree(buf); if (rc < 0 || rc != len) { pr_err("vfs_writev() returned %d for write same\n", rc); return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } target_complete_cmd(cmd, SAM_STAT_GOOD); return 0; } static sense_reason_t fd_do_unmap(struct se_cmd *cmd, void *priv, sector_t lba, sector_t nolb) { struct file *file = priv; struct inode *inode = file->f_mapping->host; int ret; if (S_ISBLK(inode->i_mode)) { /* The backend is block device, use discard */ struct block_device *bdev = inode->i_bdev; ret = blkdev_issue_discard(bdev, lba, 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_write_same_unmap(struct se_cmd *cmd) { struct se_device *se_dev = cmd->se_dev; struct fd_dev *fd_dev = FD_DEV(se_dev); struct file *file = fd_dev->fd_file; sector_t lba = cmd->t_task_lba; sector_t nolb = sbc_get_write_same_sectors(cmd); int ret; if (!nolb) { target_complete_cmd(cmd, SAM_STAT_GOOD); return 0; } ret = fd_do_unmap(cmd, file, lba, nolb); if (ret) return ret; target_complete_cmd(cmd, GOOD); return 0; } static sense_reason_t fd_execute_unmap(struct se_cmd *cmd) { struct file *file = FD_DEV(cmd->se_dev)->fd_file; return sbc_execute_unmap(cmd, fd_do_unmap, file); } static sense_reason_t fd_execute_rw(struct se_cmd *cmd) { struct scatterlist *sgl = cmd->t_data_sg; u32 sgl_nents = cmd->t_data_nents; enum dma_data_direction data_direction = cmd->data_direction; struct se_device *dev = cmd->se_dev; 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) { ret = fd_do_rw(cmd, sgl, sgl_nents, 0); } else { ret = fd_do_rw(cmd, sgl, sgl_nents, 1); /* * Perform implict 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 && dev->dev_attrib.emulate_fua_write > 0 && (cmd->se_cmd_flags & SCF_FUA)) { struct fd_dev *fd_dev = FD_DEV(dev); loff_t start = cmd->t_task_lba * dev->dev_attrib.block_size; loff_t end = start + cmd->data_length; vfs_fsync_range(fd_dev->fd_file, start, end, 1); } } if (ret < 0) return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; if (ret) target_complete_cmd(cmd, SAM_STAT_GOOD); return 0; } enum { Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_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_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 = strict_strtoull(arg_p, 0, &fd_dev->fd_dev_size); kfree(arg_p); if (ret < 0) { pr_err("strict_strtoull() 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: match_int(args, &arg); 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; 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\n", fd_dev->fd_dev_name, fd_dev->fd_dev_size, (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ? "Buffered-WCE" : "O_DSYNC"); 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 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_write_same_unmap = fd_execute_write_same_unmap, .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 struct se_subsystem_api fileio_template = { .name = "fileio", .inquiry_prod = "FILEIO", .inquiry_rev = FD_VERSION, .owner = THIS_MODULE, .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV, .attach_hba = fd_attach_hba, .detach_hba = fd_detach_hba, .alloc_device = fd_alloc_device, .configure_device = fd_configure_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, }; static int __init fileio_module_init(void) { return transport_subsystem_register(&fileio_template); } static void __exit fileio_module_exit(void) { transport_subsystem_release(&fileio_template); } 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);