target_core_file.rar_V2

/* * This file contains the Storage Engine <-> FILEIO transport specific functions */ #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\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); /* * 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.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_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 (re