diff options
Diffstat (limited to 'drivers/target/target_core_file.c')
| -rw-r--r-- | drivers/target/target_core_file.c | 688 |
1 files changed, 688 insertions, 0 deletions
diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c new file mode 100644 index 00000000000..0aaca885668 --- /dev/null +++ b/drivers/target/target_core_file.c @@ -0,0 +1,688 @@ +/******************************************************************************* + * Filename: target_core_file.c + * + * This file contains the Storage Engine <-> FILEIO transport specific functions + * + * Copyright (c) 2005 PyX Technologies, Inc. + * Copyright (c) 2005-2006 SBE, Inc. All Rights Reserved. + * Copyright (c) 2007-2010 Rising Tide Systems + * Copyright (c) 2008-2010 Linux-iSCSI.org + * + * 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/version.h> +#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/smp_lock.h> +#include <scsi/scsi.h> +#include <scsi/scsi_host.h> + +#include <target/target_core_base.h> +#include <target/target_core_device.h> +#include <target/target_core_transport.h> + +#include "target_core_file.h" + +#if 1 +#define DEBUG_FD_CACHE(x...) printk(x) +#else +#define DEBUG_FD_CACHE(x...) +#endif + +#if 1 +#define DEBUG_FD_FUA(x...) printk(x) +#else +#define DEBUG_FD_FUA(x...) +#endif + +static struct se_subsystem_api fileio_template; + +/* 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)) { + printk(KERN_ERR "Unable to allocate memory for struct fd_host\n"); + return -1; + } + + fd_host->fd_host_id = host_id; + + atomic_set(&hba->left_queue_depth, FD_HBA_QUEUE_DEPTH); + atomic_set(&hba->max_queue_depth, FD_HBA_QUEUE_DEPTH); + hba->hba_ptr = (void *) fd_host; + + printk(KERN_INFO "CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic" + " Target Core Stack %s\n", hba->hba_id, FD_VERSION, + TARGET_CORE_MOD_VERSION); + printk(KERN_INFO "CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic" + " Target Core with TCQ Depth: %d MaxSectors: %u\n", + hba->hba_id, fd_host->fd_host_id, + atomic_read(&hba->max_queue_depth), FD_MAX_SECTORS); + + return 0; +} + +static void fd_detach_hba(struct se_hba *hba) +{ + struct fd_host *fd_host = hba->hba_ptr; + + printk(KERN_INFO "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 void *fd_allocate_virtdevice(struct se_hba *hba, const char *name) +{ + struct fd_dev *fd_dev; + struct fd_host *fd_host = (struct fd_host *) hba->hba_ptr; + + fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL); + if (!(fd_dev)) { + printk(KERN_ERR "Unable to allocate memory for struct fd_dev\n"); + return NULL; + } + + fd_dev->fd_host = fd_host; + + printk(KERN_INFO "FILEIO: Allocated fd_dev for %p\n", name); + + return fd_dev; +} + +/* fd_create_virtdevice(): (Part of se_subsystem_api_t template) + * + * + */ +static struct se_device *fd_create_virtdevice( + struct se_hba *hba, + struct se_subsystem_dev *se_dev, + void *p) +{ + char *dev_p = NULL; + struct se_device *dev; + struct se_dev_limits dev_limits; + struct queue_limits *limits; + struct fd_dev *fd_dev = (struct fd_dev *) p; + struct fd_host *fd_host = (struct fd_host *) hba->hba_ptr; + mm_segment_t old_fs; + struct file *file; + struct inode *inode = NULL; + int dev_flags = 0, flags; + + memset(&dev_limits, 0, sizeof(struct se_dev_limits)); + + old_fs = get_fs(); + set_fs(get_ds()); + dev_p = getname(fd_dev->fd_dev_name); + set_fs(old_fs); + + if (IS_ERR(dev_p)) { + printk(KERN_ERR "getname(%s) failed: %lu\n", + fd_dev->fd_dev_name, IS_ERR(dev_p)); + goto fail; + } +#if 0 + if (di->no_create_file) + flags = O_RDWR | O_LARGEFILE; + else + flags = O_RDWR | O_CREAT | O_LARGEFILE; +#else + flags = O_RDWR | O_CREAT | O_LARGEFILE; +#endif +/* flags |= O_DIRECT; */ + /* + * If fd_buffered_io=1 has not been set explictly (the default), + * use O_SYNC to force FILEIO writes to disk. + */ + if (!(fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO)) + flags |= O_SYNC; + + file = filp_open(dev_p, flags, 0600); + + if (IS_ERR(file) || !file || !file->f_dentry) { + printk(KERN_ERR "filp_open(%s) failed\n", dev_p); + 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; + /* + * Setup the local scope queue_limits from struct request_queue->limits + * to pass into transport_add_device_to_core_hba() as struct se_dev_limits. + */ + q = bdev_get_queue(inode->i_bdev); + limits = &dev_limits.limits; + limits->logical_block_size = bdev_logical_block_size(inode->i_bdev); + limits->max_hw_sectors = queue_max_hw_sectors(q); + limits->max_sectors = queue_max_sectors(q); + /* + * Determine the number of bytes from i_size_read() minus + * one (1) logical sector from underlying struct block_device + */ + fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev); + fd_dev->fd_dev_size = (i_size_read(file->f_mapping->host) - + fd_dev->fd_block_size); + + printk(KERN_INFO "FILEIO: Using size: %llu bytes from struct" + " block_device blocks: %llu logical_block_size: %d\n", + fd_dev->fd_dev_size, + div_u64(fd_dev->fd_dev_size, fd_dev->fd_block_size), + fd_dev->fd_block_size); + } else { + if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) { + printk(KERN_ERR "FILEIO: Missing fd_dev_size=" + " parameter, and no backing struct" + " block_device\n"); + goto fail; + } + + limits = &dev_limits.limits; + limits->logical_block_size = FD_BLOCKSIZE; + limits->max_hw_sectors = FD_MAX_SECTORS; + limits->max_sectors = FD_MAX_SECTORS; + fd_dev->fd_block_size = FD_BLOCKSIZE; + } + + dev_limits.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH; + dev_limits.queue_depth = FD_DEVICE_QUEUE_DEPTH; + + dev = transport_add_device_to_core_hba(hba, &fileio_template, + se_dev, dev_flags, (void *)fd_dev, + &dev_limits, "FILEIO", FD_VERSION); + if (!(dev)) + goto fail; + + fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++; + fd_dev->fd_queue_depth = dev->queue_depth; + + printk(KERN_INFO "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); + + putname(dev_p); + return dev; +fail: + if (fd_dev->fd_file) { + filp_close(fd_dev->fd_file, NULL); + fd_dev->fd_file = NULL; + } + putname(dev_p); + return NULL; +} + +/* fd_free_device(): (Part of se_subsystem_api_t template) + * + * + */ +static void fd_free_device(void *p) +{ + struct fd_dev *fd_dev = (struct fd_dev *) p; + + if (fd_dev->fd_file) { + filp_close(fd_dev->fd_file, NULL); + fd_dev->fd_file = NULL; + } + + kfree(fd_dev); +} + +static inline struct fd_request *FILE_REQ(struct se_task *task) +{ + return container_of(task, struct fd_request, fd_task); +} + + +static struct se_task * +fd_alloc_task(struct se_cmd *cmd) +{ + struct fd_request *fd_req; + + fd_req = kzalloc(sizeof(struct fd_request), GFP_KERNEL); + if (!(fd_req)) { + printk(KERN_ERR "Unable to allocate struct fd_request\n"); + return NULL; + } + + fd_req->fd_dev = SE_DEV(cmd)->dev_ptr; + + return &fd_req->fd_task; +} + +static int fd_do_readv(struct se_task *task) +{ + struct fd_request *req = FILE_REQ(task); + struct file *fd = req->fd_dev->fd_file; + struct scatterlist *sg = task->task_sg; + struct iovec *iov; + mm_segment_t old_fs; + loff_t pos = (task->task_lba * DEV_ATTRIB(task->se_dev)->block_size); + int ret = 0, i; + + iov = kzalloc(sizeof(struct iovec) * task->task_sg_num, GFP_KERNEL); + if (!(iov)) { + printk(KERN_ERR "Unable to allocate fd_do_readv iov[]\n"); + return -1; + } + + for (i = 0; i < task->task_sg_num; i++) { + iov[i].iov_len = sg[i].length; + iov[i].iov_base = sg_virt(&sg[i]); + } + + old_fs = get_fs(); + set_fs(get_ds()); + ret = vfs_readv(fd, &iov[0], task->task_sg_num, &pos); + set_fs(old_fs); + + kfree(iov); + /* + * 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(fd->f_dentry->d_inode->i_mode)) { + if (ret < 0 || ret != task->task_size) { + printk(KERN_ERR "vfs_readv() returned %d," + " expecting %d for S_ISBLK\n", ret, + (int)task->task_size); + return -1; + } + } else { + if (ret < 0) { + printk(KERN_ERR "vfs_readv() returned %d for non" + " S_ISBLK\n", ret); + return -1; + } + } + + return 1; +} + +static int fd_do_writev(struct se_task *task) +{ + struct fd_request *req = FILE_REQ(task); + struct file *fd = req->fd_dev->fd_file; + struct scatterlist *sg = task->task_sg; + struct iovec *iov; + mm_segment_t old_fs; + loff_t pos = (task->task_lba * DEV_ATTRIB(task->se_dev)->block_size); + int ret, i = 0; + + iov = kzalloc(sizeof(struct iovec) * task->task_sg_num, GFP_KERNEL); + if (!(iov)) { + printk(KERN_ERR "Unable to allocate fd_do_writev iov[]\n"); + return -1; + } + + for (i = 0; i < task->task_sg_num; i++) { + iov[i].iov_len = sg[i].length; + iov[i].iov_base = sg_virt(&sg[i]); + } + + old_fs = get_fs(); + set_fs(get_ds()); + ret = vfs_writev(fd, &iov[0], task->task_sg_num, &pos); + set_fs(old_fs); + + kfree(iov); + + if (ret < 0 || ret != task->task_size) { + printk(KERN_ERR "vfs_writev() returned %d\n", ret); + return -1; + } + + return 1; +} + +static void fd_emulate_sync_cache(struct se_task *task) +{ + struct se_cmd *cmd = TASK_CMD(task); + struct se_device *dev = cmd->se_dev; + struct fd_dev *fd_dev = dev->dev_ptr; + int immed = (cmd->t_task->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) + transport_complete_sync_cache(cmd, 1); + + /* + * Determine if we will be flushing the entire device. + */ + if (cmd->t_task->t_task_lba == 0 && cmd->data_length == 0) { + start = 0; + end = LLONG_MAX; + } else { + start = cmd->t_task->t_task_lba * DEV_ATTRIB(dev)->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) + printk(KERN_ERR "FILEIO: vfs_fsync_range() failed: %d\n", ret); + + if (!immed) + transport_complete_sync_cache(cmd, ret == 0); +} + +/* + * Tell TCM Core that we are capable of WriteCache emulation for + * an underlying struct se_device. + */ +static int fd_emulated_write_cache(struct se_device *dev) +{ + return 1; +} + +static int fd_emulated_dpo(struct se_device *dev) +{ + return 0; +} +/* + * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs + * for TYPE_DISK. + */ +static int fd_emulated_fua_write(struct se_device *dev) +{ + return 1; +} + +static int fd_emulated_fua_read(struct se_device *dev) +{ + return 0; +} + +/* + * WRITE Force Unit Access (FUA) emulation on a per struct se_task + * LBA range basis.. + */ +static void fd_emulate_write_fua(struct se_cmd *cmd, struct se_task *task) +{ + struct se_device *dev = cmd->se_dev; + struct fd_dev *fd_dev = dev->dev_ptr; + loff_t start = task->task_lba * DEV_ATTRIB(dev)->block_size; + loff_t end = start + task->task_size; + int ret; + + DEBUG_FD_CACHE("FILEIO: FUA WRITE LBA: %llu, bytes: %u\n", + task->task_lba, task->task_size); + + ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1); + if (ret != 0) + printk(KERN_ERR "FILEIO: vfs_fsync_range() failed: %d\n", ret); +} + +static int fd_do_task(struct se_task *task) +{ + struct se_cmd *cmd = task->task_se_cmd; + 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 (task->task_data_direction == DMA_FROM_DEVICE) { + ret = fd_do_readv(task); + } else { + ret = fd_do_writev(task); + + if (ret > 0 && + DEV_ATTRIB(dev)->emulate_write_cache > 0 && + DEV_ATTRIB(dev)->emulate_fua_write > 0 && + T_TASK(cmd)->t_tasks_fua) { + /* + * We might need to be a bit smarter here + * and return some sense data to let the initiator + * know the FUA WRITE cache sync failed..? + */ + fd_emulate_write_fua(cmd, task); + } + + } + + if (ret < 0) + return ret; + if (ret) { + task->task_scsi_status = GOOD; + transport_complete_task(task, 1); + } + return PYX_TRANSPORT_SENT_TO_TRANSPORT; +} + +/* fd_free_task(): (Part of se_subsystem_api_t template) + * + * + */ +static void fd_free_task(struct se_task *task) +{ + struct fd_request *req = FILE_REQ(task); + + kfree(req); +} + +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_id=%d"}, + {Opt_err, NULL} +}; + +static ssize_t fd_set_configfs_dev_params( + struct se_hba *hba, + struct se_subsystem_dev *se_dev, + const char *page, ssize_t count) +{ + struct fd_dev *fd_dev = se_dev->se_dev_su_ptr; + 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, ",")) != NULL) { + if (!*ptr) + continue; + + token = match_token(ptr, tokens, args); + switch (token) { + case Opt_fd_dev_name: + snprintf(fd_dev->fd_dev_name, FD_MAX_DEV_NAME, + "%s", match_strdup(&args[0])); + printk(KERN_INFO "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]); + ret = strict_strtoull(arg_p, 0, &fd_dev->fd_dev_size); + if (ret < 0) { + printk(KERN_ERR "strict_strtoull() failed for" + " fd_dev_size=\n"); + goto out; + } + printk(KERN_INFO "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) { + printk(KERN_ERR "bogus fd_buffered_io=%d value\n", arg); + ret = -EINVAL; + goto out; + } + + printk(KERN_INFO "FILEIO: Using buffered I/O" + " operations for struct fd_dev\n"); + + fd_dev->fbd_flags |= FDBD_USE_BUFFERED_IO; + break; + default: + break; + } + } + +out: + kfree(orig); + return (!ret) ? count : ret; +} + +static ssize_t fd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev) +{ + struct fd_dev *fd_dev = (struct fd_dev *) se_dev->se_dev_su_ptr; + + if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) { + printk(KERN_ERR "Missing fd_dev_name=\n"); + return -1; + } + + return 0; +} + +static ssize_t fd_show_configfs_dev_params( + struct se_hba *hba, + struct se_subsystem_dev *se_dev, + char *b) +{ + struct fd_dev *fd_dev = se_dev->se_dev_su_ptr; + 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_USE_BUFFERED_IO) ? + "Buffered" : "Synchronous"); + return bl; +} + +/* fd_get_cdb(): (Part of se_subsystem_api_t template) + * + * + */ +static unsigned char *fd_get_cdb(struct se_task *task) +{ + struct fd_request *req = FILE_REQ(task); + + return req->fd_scsi_cdb; +} + +/* fd_get_device_rev(): (Part of se_subsystem_api_t template) + * + * + */ +static u32 fd_get_device_rev(struct se_device *dev) +{ + return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */ +} + +/* fd_get_device_type(): (Part of se_subsystem_api_t template) + * + * + */ +static u32 fd_get_device_type(struct se_device *dev) +{ + return TYPE_DISK; +} + +static sector_t fd_get_blocks(struct se_device *dev) +{ + struct fd_dev *fd_dev = dev->dev_ptr; + unsigned long long blocks_long = div_u64(fd_dev->fd_dev_size, + DEV_ATTRIB(dev)->block_size); + + return blocks_long; +} + +static struct se_subsystem_api fileio_template = { + .name = "fileio", + .owner = THIS_MODULE, + .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV, + .attach_hba = fd_attach_hba, + .detach_hba = fd_detach_hba, + .allocate_virtdevice = fd_allocate_virtdevice, + .create_virtdevice = fd_create_virtdevice, + .free_device = fd_free_device, + .dpo_emulated = fd_emulated_dpo, + .fua_write_emulated = fd_emulated_fua_write, + .fua_read_emulated = fd_emulated_fua_read, + .write_cache_emulated = fd_emulated_write_cache, + .alloc_task = fd_alloc_task, + .do_task = fd_do_task, + .do_sync_cache = fd_emulate_sync_cache, + .free_task = fd_free_task, + .check_configfs_dev_params = fd_check_configfs_dev_params, + .set_configfs_dev_params = fd_set_configfs_dev_params, + .show_configfs_dev_params = fd_show_configfs_dev_params, + .get_cdb = fd_get_cdb, + .get_device_rev = fd_get_device_rev, + .get_device_type = fd_get_device_type, + .get_blocks = fd_get_blocks, +}; + +static int __init fileio_module_init(void) +{ + return transport_subsystem_register(&fileio_template); +} + +static void 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); |