| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Michael Christie | 5151 | 42.17% | 38 | 35.19% |
| Andy Grover | 2808 | 22.99% | 10 | 9.26% |
| Xiubo Li | 2033 | 16.64% | 12 | 11.11% |
| Bryant G. Ly | 545 | 4.46% | 7 | 6.48% |
| Zhu Lingshan | 435 | 3.56% | 6 | 5.56% |
| Sheng Yang | 327 | 2.68% | 7 | 6.48% |
| Ilias Tsitsimpis | 269 | 2.20% | 3 | 2.78% |
| Nicholas Bellinger | 242 | 1.98% | 3 | 2.78% |
| Kenjiro Nakayama | 177 | 1.45% | 2 | 1.85% |
| Bodo Stroesser | 143 | 1.17% | 1 | 0.93% |
| Prasanna Kumar Kalever | 16 | 0.13% | 1 | 0.93% |
| Kees Cook | 13 | 0.11% | 2 | 1.85% |
| Tang Wenji | 13 | 0.11% | 1 | 0.93% |
| Bart Van Assche | 11 | 0.09% | 3 | 2.78% |
| Wei Yongjun | 7 | 0.06% | 1 | 0.93% |
| Sagi Grimberg | 4 | 0.03% | 1 | 0.93% |
| Christoph Hellwig | 4 | 0.03% | 1 | 0.93% |
| David Disseldorp | 4 | 0.03% | 1 | 0.93% |
| David S. Miller | 3 | 0.02% | 1 | 0.93% |
| Geliang Tang | 3 | 0.02% | 1 | 0.93% |
| Arnd Bergmann | 3 | 0.02% | 1 | 0.93% |
| Colin Ian King | 1 | 0.01% | 1 | 0.93% |
| Matthew Wilcox | 1 | 0.01% | 1 | 0.93% |
| Mark Rutland | 1 | 0.01% | 1 | 0.93% |
| Randy Dunlap | 1 | 0.01% | 1 | 0.93% |
| Souptick Joarder | 1 | 0.01% | 1 | 0.93% |
| Total | 12216 | 108 |
/* * Copyright (C) 2013 Shaohua Li <shli@kernel.org> * Copyright (C) 2014 Red Hat, Inc. * Copyright (C) 2015 Arrikto, Inc. * Copyright (C) 2017 Chinamobile, Inc. * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope 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., * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. */ #include <linux/spinlock.h> #include <linux/module.h> #include <linux/idr.h> #include <linux/kernel.h> #include <linux/timer.h> #include <linux/parser.h> #include <linux/vmalloc.h> #include <linux/uio_driver.h> #include <linux/radix-tree.h> #include <linux/stringify.h> #include <linux/bitops.h> #include <linux/highmem.h> #include <linux/configfs.h> #include <linux/mutex.h> #include <linux/workqueue.h> #include <net/genetlink.h> #include <scsi/scsi_common.h> #include <scsi/scsi_proto.h> #include <target/target_core_base.h> #include <target/target_core_fabric.h> #include <target/target_core_backend.h> #include <linux/target_core_user.h> /** * DOC: Userspace I/O * Userspace I/O * ------------- * * Define a shared-memory interface for LIO to pass SCSI commands and * data to userspace for processing. This is to allow backends that * are too complex for in-kernel support to be possible. * * It uses the UIO framework to do a lot of the device-creation and * introspection work for us. * * See the .h file for how the ring is laid out. Note that while the * command ring is defined, the particulars of the data area are * not. Offset values in the command entry point to other locations * internal to the mmap-ed area. There is separate space outside the * command ring for data buffers. This leaves maximum flexibility for * moving buffer allocations, or even page flipping or other * allocation techniques, without altering the command ring layout. * * SECURITY: * The user process must be assumed to be malicious. There's no way to * prevent it breaking the command ring protocol if it wants, but in * order to prevent other issues we must only ever read *data* from * the shared memory area, not offsets or sizes. This applies to * command ring entries as well as the mailbox. Extra code needed for * this may have a 'UAM' comment. */ #define TCMU_TIME_OUT (30 * MSEC_PER_SEC) /* For cmd area, the size is fixed 8MB */ #define CMDR_SIZE (8 * 1024 * 1024) /* * For data area, the block size is PAGE_SIZE and * the total size is 256K * PAGE_SIZE. */ #define DATA_BLOCK_SIZE PAGE_SIZE #define DATA_BLOCK_SHIFT PAGE_SHIFT #define DATA_BLOCK_BITS_DEF (256 * 1024) #define TCMU_MBS_TO_BLOCKS(_mbs) (_mbs << (20 - DATA_BLOCK_SHIFT)) #define TCMU_BLOCKS_TO_MBS(_blocks) (_blocks >> (20 - DATA_BLOCK_SHIFT)) /* * Default number of global data blocks(512K * PAGE_SIZE) * when the unmap thread will be started. */ #define TCMU_GLOBAL_MAX_BLOCKS_DEF (512 * 1024) static u8 tcmu_kern_cmd_reply_supported; static u8 tcmu_netlink_blocked; static struct device *tcmu_root_device; struct tcmu_hba { u32 host_id; }; #define TCMU_CONFIG_LEN 256 static DEFINE_MUTEX(tcmu_nl_cmd_mutex); static LIST_HEAD(tcmu_nl_cmd_list); struct tcmu_dev; struct tcmu_nl_cmd { /* wake up thread waiting for reply */ struct completion complete; struct list_head nl_list; struct tcmu_dev *udev; int cmd; int status; }; struct tcmu_dev { struct list_head node; struct kref kref; struct se_device se_dev; char *name; struct se_hba *hba; #define TCMU_DEV_BIT_OPEN 0 #define TCMU_DEV_BIT_BROKEN 1 #define TCMU_DEV_BIT_BLOCKED 2 unsigned long flags; struct uio_info uio_info; struct inode *inode; struct tcmu_mailbox *mb_addr; uint64_t dev_size; u32 cmdr_size; u32 cmdr_last_cleaned; /* Offset of data area from start of mb */ /* Must add data_off and mb_addr to get the address */ size_t data_off; size_t data_size; uint32_t max_blocks; size_t ring_size; struct mutex cmdr_lock; struct list_head cmdr_queue; uint32_t dbi_max; uint32_t dbi_thresh; unsigned long *data_bitmap; struct radix_tree_root data_blocks; struct idr commands; struct timer_list cmd_timer; unsigned int cmd_time_out; struct timer_list qfull_timer; int qfull_time_out; struct list_head timedout_entry; struct tcmu_nl_cmd curr_nl_cmd; char dev_config[TCMU_CONFIG_LEN]; int nl_reply_supported; }; #define TCMU_DEV(_se_dev) container_of(_se_dev, struct tcmu_dev, se_dev) #define CMDR_OFF sizeof(struct tcmu_mailbox) struct tcmu_cmd { struct se_cmd *se_cmd; struct tcmu_dev *tcmu_dev; struct list_head cmdr_queue_entry; uint16_t cmd_id; /* Can't use se_cmd when cleaning up expired cmds, because if cmd has been completed then accessing se_cmd is off limits */ uint32_t dbi_cnt; uint32_t dbi_cur; uint32_t *dbi; unsigned long deadline; #define TCMU_CMD_BIT_EXPIRED 0 unsigned long flags; }; /* * To avoid dead lock the mutex lock order should always be: * * mutex_lock(&root_udev_mutex); * ... * mutex_lock(&tcmu_dev->cmdr_lock); * mutex_unlock(&tcmu_dev->cmdr_lock); * ... * mutex_unlock(&root_udev_mutex); */ static DEFINE_MUTEX(root_udev_mutex); static LIST_HEAD(root_udev); static DEFINE_SPINLOCK(timed_out_udevs_lock); static LIST_HEAD(timed_out_udevs); static struct kmem_cache *tcmu_cmd_cache; static atomic_t global_db_count = ATOMIC_INIT(0); static struct delayed_work tcmu_unmap_work; static int tcmu_global_max_blocks = TCMU_GLOBAL_MAX_BLOCKS_DEF; static int tcmu_set_global_max_data_area(const char *str, const struct kernel_param *kp) { int ret, max_area_mb; ret = kstrtoint(str, 10, &max_area_mb); if (ret) return -EINVAL; if (max_area_mb <= 0) { pr_err("global_max_data_area must be larger than 0.\n"); return -EINVAL; } tcmu_global_max_blocks = TCMU_MBS_TO_BLOCKS(max_area_mb); if (atomic_read(&global_db_count) > tcmu_global_max_blocks) schedule_delayed_work(&tcmu_unmap_work, 0); else cancel_delayed_work_sync(&tcmu_unmap_work); return 0; } static int tcmu_get_global_max_data_area(char *buffer, const struct kernel_param *kp) { return sprintf(buffer, "%d", TCMU_BLOCKS_TO_MBS(tcmu_global_max_blocks)); } static const struct kernel_param_ops tcmu_global_max_data_area_op = { .set = tcmu_set_global_max_data_area, .get = tcmu_get_global_max_data_area, }; module_param_cb(global_max_data_area_mb, &tcmu_global_max_data_area_op, NULL, S_IWUSR | S_IRUGO); MODULE_PARM_DESC(global_max_data_area_mb, "Max MBs allowed to be allocated to all the tcmu device's " "data areas."); static int tcmu_get_block_netlink(char *buffer, const struct kernel_param *kp) { return sprintf(buffer, "%s\n", tcmu_netlink_blocked ? "blocked" : "unblocked"); } static int tcmu_set_block_netlink(const char *str, const struct kernel_param *kp) { int ret; u8 val; ret = kstrtou8(str, 0, &val); if (ret < 0) return ret; if (val > 1) { pr_err("Invalid block netlink value %u\n", val); return -EINVAL; } tcmu_netlink_blocked = val; return 0; } static const struct kernel_param_ops tcmu_block_netlink_op = { .set = tcmu_set_block_netlink, .get = tcmu_get_block_netlink, }; module_param_cb(block_netlink, &tcmu_block_netlink_op, NULL, S_IWUSR | S_IRUGO); MODULE_PARM_DESC(block_netlink, "Block new netlink commands."); static int tcmu_fail_netlink_cmd(struct tcmu_nl_cmd *nl_cmd) { struct tcmu_dev *udev = nl_cmd->udev; if (!tcmu_netlink_blocked) { pr_err("Could not reset device's netlink interface. Netlink is not blocked.\n"); return -EBUSY; } if (nl_cmd->cmd != TCMU_CMD_UNSPEC) { pr_debug("Aborting nl cmd %d on %s\n", nl_cmd->cmd, udev->name); nl_cmd->status = -EINTR; list_del(&nl_cmd->nl_list); complete(&nl_cmd->complete); } return 0; } static int tcmu_set_reset_netlink(const char *str, const struct kernel_param *kp) { struct tcmu_nl_cmd *nl_cmd, *tmp_cmd; int ret; u8 val; ret = kstrtou8(str, 0, &val); if (ret < 0) return ret; if (val != 1) { pr_err("Invalid reset netlink value %u\n", val); return -EINVAL; } mutex_lock(&tcmu_nl_cmd_mutex); list_for_each_entry_safe(nl_cmd, tmp_cmd, &tcmu_nl_cmd_list, nl_list) { ret = tcmu_fail_netlink_cmd(nl_cmd); if (ret) break; } mutex_unlock(&tcmu_nl_cmd_mutex); return ret; } static const struct kernel_param_ops tcmu_reset_netlink_op = { .set = tcmu_set_reset_netlink, }; module_param_cb(reset_netlink, &tcmu_reset_netlink_op, NULL, S_IWUSR); MODULE_PARM_DESC(reset_netlink, "Reset netlink commands."); /* multicast group */ enum tcmu_multicast_groups { TCMU_MCGRP_CONFIG, }; static const struct genl_multicast_group tcmu_mcgrps[] = { [TCMU_MCGRP_CONFIG] = { .name = "config", }, }; static struct nla_policy tcmu_attr_policy[TCMU_ATTR_MAX+1] = { [TCMU_ATTR_DEVICE] = { .type = NLA_STRING }, [TCMU_ATTR_MINOR] = { .type = NLA_U32 }, [TCMU_ATTR_CMD_STATUS] = { .type = NLA_S32 }, [TCMU_ATTR_DEVICE_ID] = { .type = NLA_U32 }, [TCMU_ATTR_SUPP_KERN_CMD_REPLY] = { .type = NLA_U8 }, }; static int tcmu_genl_cmd_done(struct genl_info *info, int completed_cmd) { struct tcmu_dev *udev = NULL; struct tcmu_nl_cmd *nl_cmd; int dev_id, rc, ret = 0; if (!info->attrs[TCMU_ATTR_CMD_STATUS] || !info->attrs[TCMU_ATTR_DEVICE_ID]) { printk(KERN_ERR "TCMU_ATTR_CMD_STATUS or TCMU_ATTR_DEVICE_ID not set, doing nothing\n"); return -EINVAL; } dev_id = nla_get_u32(info->attrs[TCMU_ATTR_DEVICE_ID]); rc = nla_get_s32(info->attrs[TCMU_ATTR_CMD_STATUS]); mutex_lock(&tcmu_nl_cmd_mutex); list_for_each_entry(nl_cmd, &tcmu_nl_cmd_list, nl_list) { if (nl_cmd->udev->se_dev.dev_index == dev_id) { udev = nl_cmd->udev; break; } } if (!udev) { pr_err("tcmu nl cmd %u/%d completion could not find device with dev id %u.\n", completed_cmd, rc, dev_id); ret = -ENODEV; goto unlock; } list_del(&nl_cmd->nl_list); pr_debug("%s genl cmd done got id %d curr %d done %d rc %d stat %d\n", udev->name, dev_id, nl_cmd->cmd, completed_cmd, rc, nl_cmd->status); if (nl_cmd->cmd != completed_cmd) { pr_err("Mismatched commands on %s (Expecting reply for %d. Current %d).\n", udev->name, completed_cmd, nl_cmd->cmd); ret = -EINVAL; goto unlock; } nl_cmd->status = rc; complete(&nl_cmd->complete); unlock: mutex_unlock(&tcmu_nl_cmd_mutex); return ret; } static int tcmu_genl_rm_dev_done(struct sk_buff *skb, struct genl_info *info) { return tcmu_genl_cmd_done(info, TCMU_CMD_REMOVED_DEVICE); } static int tcmu_genl_add_dev_done(struct sk_buff *skb, struct genl_info *info) { return tcmu_genl_cmd_done(info, TCMU_CMD_ADDED_DEVICE); } static int tcmu_genl_reconfig_dev_done(struct sk_buff *skb, struct genl_info *info) { return tcmu_genl_cmd_done(info, TCMU_CMD_RECONFIG_DEVICE); } static int tcmu_genl_set_features(struct sk_buff *skb, struct genl_info *info) { if (info->attrs[TCMU_ATTR_SUPP_KERN_CMD_REPLY]) { tcmu_kern_cmd_reply_supported = nla_get_u8(info->attrs[TCMU_ATTR_SUPP_KERN_CMD_REPLY]); printk(KERN_INFO "tcmu daemon: command reply support %u.\n", tcmu_kern_cmd_reply_supported); } return 0; } static const struct genl_ops tcmu_genl_ops[] = { { .cmd = TCMU_CMD_SET_FEATURES, .flags = GENL_ADMIN_PERM, .policy = tcmu_attr_policy, .doit = tcmu_genl_set_features, }, { .cmd = TCMU_CMD_ADDED_DEVICE_DONE, .flags = GENL_ADMIN_PERM, .policy = tcmu_attr_policy, .doit = tcmu_genl_add_dev_done, }, { .cmd = TCMU_CMD_REMOVED_DEVICE_DONE, .flags = GENL_ADMIN_PERM, .policy = tcmu_attr_policy, .doit = tcmu_genl_rm_dev_done, }, { .cmd = TCMU_CMD_RECONFIG_DEVICE_DONE, .flags = GENL_ADMIN_PERM, .policy = tcmu_attr_policy, .doit = tcmu_genl_reconfig_dev_done, }, }; /* Our generic netlink family */ static struct genl_family tcmu_genl_family __ro_after_init = { .module = THIS_MODULE, .hdrsize = 0, .name = "TCM-USER", .version = 2, .maxattr = TCMU_ATTR_MAX, .mcgrps = tcmu_mcgrps, .n_mcgrps = ARRAY_SIZE(tcmu_mcgrps), .netnsok = true, .ops = tcmu_genl_ops, .n_ops = ARRAY_SIZE(tcmu_genl_ops), }; #define tcmu_cmd_set_dbi_cur(cmd, index) ((cmd)->dbi_cur = (index)) #define tcmu_cmd_reset_dbi_cur(cmd) tcmu_cmd_set_dbi_cur(cmd, 0) #define tcmu_cmd_set_dbi(cmd, index) ((cmd)->dbi[(cmd)->dbi_cur++] = (index)) #define tcmu_cmd_get_dbi(cmd) ((cmd)->dbi[(cmd)->dbi_cur++]) static void tcmu_cmd_free_data(struct tcmu_cmd *tcmu_cmd, uint32_t len) { struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; uint32_t i; for (i = 0; i < len; i++) clear_bit(tcmu_cmd->dbi[i], udev->data_bitmap); } static inline bool tcmu_get_empty_block(struct tcmu_dev *udev, struct tcmu_cmd *tcmu_cmd) { struct page *page; int ret, dbi; dbi = find_first_zero_bit(udev->data_bitmap, udev->dbi_thresh); if (dbi == udev->dbi_thresh) return false; page = radix_tree_lookup(&udev->data_blocks, dbi); if (!page) { if (atomic_add_return(1, &global_db_count) > tcmu_global_max_blocks) schedule_delayed_work(&tcmu_unmap_work, 0); /* try to get new page from the mm */ page = alloc_page(GFP_KERNEL); if (!page) goto err_alloc; ret = radix_tree_insert(&udev->data_blocks, dbi, page); if (ret) goto err_insert; } if (dbi > udev->dbi_max) udev->dbi_max = dbi; set_bit(dbi, udev->data_bitmap); tcmu_cmd_set_dbi(tcmu_cmd, dbi); return true; err_insert: __free_page(page); err_alloc: atomic_dec(&global_db_count); return false; } static bool tcmu_get_empty_blocks(struct tcmu_dev *udev, struct tcmu_cmd *tcmu_cmd) { int i; for (i = tcmu_cmd->dbi_cur; i < tcmu_cmd->dbi_cnt; i++) { if (!tcmu_get_empty_block(udev, tcmu_cmd)) return false; } return true; } static inline struct page * tcmu_get_block_page(struct tcmu_dev *udev, uint32_t dbi) { return radix_tree_lookup(&udev->data_blocks, dbi); } static inline void tcmu_free_cmd(struct tcmu_cmd *tcmu_cmd) { kfree(tcmu_cmd->dbi); kmem_cache_free(tcmu_cmd_cache, tcmu_cmd); } static inline size_t tcmu_cmd_get_data_length(struct tcmu_cmd *tcmu_cmd) { struct se_cmd *se_cmd = tcmu_cmd->se_cmd; size_t data_length = round_up(se_cmd->data_length, DATA_BLOCK_SIZE); if (se_cmd->se_cmd_flags & SCF_BIDI) { BUG_ON(!(se_cmd->t_bidi_data_sg && se_cmd->t_bidi_data_nents)); data_length += round_up(se_cmd->t_bidi_data_sg->length, DATA_BLOCK_SIZE); } return data_length; } static inline uint32_t tcmu_cmd_get_block_cnt(struct tcmu_cmd *tcmu_cmd) { size_t data_length = tcmu_cmd_get_data_length(tcmu_cmd); return data_length / DATA_BLOCK_SIZE; } static struct tcmu_cmd *tcmu_alloc_cmd(struct se_cmd *se_cmd) { struct se_device *se_dev = se_cmd->se_dev; struct tcmu_dev *udev = TCMU_DEV(se_dev); struct tcmu_cmd *tcmu_cmd; tcmu_cmd = kmem_cache_zalloc(tcmu_cmd_cache, GFP_KERNEL); if (!tcmu_cmd) return NULL; INIT_LIST_HEAD(&tcmu_cmd->cmdr_queue_entry); tcmu_cmd->se_cmd = se_cmd; tcmu_cmd->tcmu_dev = udev; tcmu_cmd_reset_dbi_cur(tcmu_cmd); tcmu_cmd->dbi_cnt = tcmu_cmd_get_block_cnt(tcmu_cmd); tcmu_cmd->dbi = kcalloc(tcmu_cmd->dbi_cnt, sizeof(uint32_t), GFP_KERNEL); if (!tcmu_cmd->dbi) { kmem_cache_free(tcmu_cmd_cache, tcmu_cmd); return NULL; } return tcmu_cmd; } static inline void tcmu_flush_dcache_range(void *vaddr, size_t size) { unsigned long offset = offset_in_page(vaddr); void *start = vaddr - offset; size = round_up(size+offset, PAGE_SIZE); while (size) { flush_dcache_page(virt_to_page(start)); start += PAGE_SIZE; size -= PAGE_SIZE; } } /* * Some ring helper functions. We don't assume size is a power of 2 so * we can't use circ_buf.h. */ static inline size_t spc_used(size_t head, size_t tail, size_t size) { int diff = head - tail; if (diff >= 0) return diff; else return size + diff; } static inline size_t spc_free(size_t head, size_t tail, size_t size) { /* Keep 1 byte unused or we can't tell full from empty */ return (size - spc_used(head, tail, size) - 1); } static inline size_t head_to_end(size_t head, size_t size) { return size - head; } static inline void new_iov(struct iovec **iov, int *iov_cnt) { struct iovec *iovec; if (*iov_cnt != 0) (*iov)++; (*iov_cnt)++; iovec = *iov; memset(iovec, 0, sizeof(struct iovec)); } #define UPDATE_HEAD(head, used, size) smp_store_release(&head, ((head % size) + used) % size) /* offset is relative to mb_addr */ static inline size_t get_block_offset_user(struct tcmu_dev *dev, int dbi, int remaining) { return dev->data_off + dbi * DATA_BLOCK_SIZE + DATA_BLOCK_SIZE - remaining; } static inline size_t iov_tail(struct iovec *iov) { return (size_t)iov->iov_base + iov->iov_len; } static void scatter_data_area(struct tcmu_dev *udev, struct tcmu_cmd *tcmu_cmd, struct scatterlist *data_sg, unsigned int data_nents, struct iovec **iov, int *iov_cnt, bool copy_data) { int i, dbi; int block_remaining = 0; void *from, *to = NULL; size_t copy_bytes, to_offset, offset; struct scatterlist *sg; struct page *page; for_each_sg(data_sg, sg, data_nents, i) { int sg_remaining = sg->length; from = kmap_atomic(sg_page(sg)) + sg->offset; while (sg_remaining > 0) { if (block_remaining == 0) { if (to) kunmap_atomic(to); block_remaining = DATA_BLOCK_SIZE; dbi = tcmu_cmd_get_dbi(tcmu_cmd); page = tcmu_get_block_page(udev, dbi); to = kmap_atomic(page); } /* * Covert to virtual offset of the ring data area. */ to_offset = get_block_offset_user(udev, dbi, block_remaining); /* * The following code will gather and map the blocks * to the same iovec when the blocks are all next to * each other. */ copy_bytes = min_t(size_t, sg_remaining, block_remaining); if (*iov_cnt != 0 && to_offset == iov_tail(*iov)) { /* * Will append to the current iovec, because * the current block page is next to the * previous one. */ (*iov)->iov_len += copy_bytes; } else { /* * Will allocate a new iovec because we are * first time here or the current block page * is not next to the previous one. */ new_iov(iov, iov_cnt); (*iov)->iov_base = (void __user *)to_offset; (*iov)->iov_len = copy_bytes; } if (copy_data) { offset = DATA_BLOCK_SIZE - block_remaining; memcpy(to + offset, from + sg->length - sg_remaining, copy_bytes); tcmu_flush_dcache_range(to, copy_bytes); } sg_remaining -= copy_bytes; block_remaining -= copy_bytes; } kunmap_atomic(from - sg->offset); } if (to) kunmap_atomic(to); } static void gather_data_area(struct tcmu_dev *udev, struct tcmu_cmd *cmd, bool bidi, uint32_t read_len) { struct se_cmd *se_cmd = cmd->se_cmd; int i, dbi; int block_remaining = 0; void *from = NULL, *to; size_t copy_bytes, offset; struct scatterlist *sg, *data_sg; struct page *page; unsigned int data_nents; uint32_t count = 0; if (!bidi) { data_sg = se_cmd->t_data_sg; data_nents = se_cmd->t_data_nents; } else { /* * For bidi case, the first count blocks are for Data-Out * buffer blocks, and before gathering the Data-In buffer * the Data-Out buffer blocks should be discarded. */ count = DIV_ROUND_UP(se_cmd->data_length, DATA_BLOCK_SIZE); data_sg = se_cmd->t_bidi_data_sg; data_nents = se_cmd->t_bidi_data_nents; } tcmu_cmd_set_dbi_cur(cmd, count); for_each_sg(data_sg, sg, data_nents, i) { int sg_remaining = sg->length; to = kmap_atomic(sg_page(sg)) + sg->offset; while (sg_remaining > 0 && read_len > 0) { if (block_remaining == 0) { if (from) kunmap_atomic(from); block_remaining = DATA_BLOCK_SIZE; dbi = tcmu_cmd_get_dbi(cmd); page = tcmu_get_block_page(udev, dbi); from = kmap_atomic(page); } copy_bytes = min_t(size_t, sg_remaining, block_remaining); if (read_len < copy_bytes) copy_bytes = read_len; offset = DATA_BLOCK_SIZE - block_remaining; tcmu_flush_dcache_range(from, copy_bytes); memcpy(to + sg->length - sg_remaining, from + offset, copy_bytes); sg_remaining -= copy_bytes; block_remaining -= copy_bytes; read_len -= copy_bytes; } kunmap_atomic(to - sg->offset); if (read_len == 0) break; } if (from) kunmap_atomic(from); } static inline size_t spc_bitmap_free(unsigned long *bitmap, uint32_t thresh) { return thresh - bitmap_weight(bitmap, thresh); } /* * We can't queue a command until we have space available on the cmd ring *and* * space available on the data area. * * Called with ring lock held. */ static bool is_ring_space_avail(struct tcmu_dev *udev, struct tcmu_cmd *cmd, size_t cmd_size, size_t data_needed) { struct tcmu_mailbox *mb = udev->mb_addr; uint32_t blocks_needed = (data_needed + DATA_BLOCK_SIZE - 1) / DATA_BLOCK_SIZE; size_t space, cmd_needed; u32 cmd_head; tcmu_flush_dcache_range(mb, sizeof(*mb)); cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ /* * If cmd end-of-ring space is too small then we need space for a NOP plus * original cmd - cmds are internally contiguous. */ if (head_to_end(cmd_head, udev->cmdr_size) >= cmd_size) cmd_needed = cmd_size; else cmd_needed = cmd_size + head_to_end(cmd_head, udev->cmdr_size); space = spc_free(cmd_head, udev->cmdr_last_cleaned, udev->cmdr_size); if (space < cmd_needed) { pr_debug("no cmd space: %u %u %u\n", cmd_head, udev->cmdr_last_cleaned, udev->cmdr_size); return false; } /* try to check and get the data blocks as needed */ space = spc_bitmap_free(udev->data_bitmap, udev->dbi_thresh); if ((space * DATA_BLOCK_SIZE) < data_needed) { unsigned long blocks_left = (udev->max_blocks - udev->dbi_thresh) + space; if (blocks_left < blocks_needed) { pr_debug("no data space: only %lu available, but ask for %zu\n", blocks_left * DATA_BLOCK_SIZE, data_needed); return false; } udev->dbi_thresh += blocks_needed; if (udev->dbi_thresh > udev->max_blocks) udev->dbi_thresh = udev->max_blocks; } return tcmu_get_empty_blocks(udev, cmd); } static inline size_t tcmu_cmd_get_base_cmd_size(size_t iov_cnt) { return max(offsetof(struct tcmu_cmd_entry, req.iov[iov_cnt]), sizeof(struct tcmu_cmd_entry)); } static inline size_t tcmu_cmd_get_cmd_size(struct tcmu_cmd *tcmu_cmd, size_t base_command_size) { struct se_cmd *se_cmd = tcmu_cmd->se_cmd; size_t command_size; command_size = base_command_size + round_up(scsi_command_size(se_cmd->t_task_cdb), TCMU_OP_ALIGN_SIZE); WARN_ON(command_size & (TCMU_OP_ALIGN_SIZE-1)); return command_size; } static int tcmu_setup_cmd_timer(struct tcmu_cmd *tcmu_cmd, unsigned int tmo, struct timer_list *timer) { struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; int cmd_id; if (tcmu_cmd->cmd_id) goto setup_timer; cmd_id = idr_alloc(&udev->commands, tcmu_cmd, 1, USHRT_MAX, GFP_NOWAIT); if (cmd_id < 0) { pr_err("tcmu: Could not allocate cmd id.\n"); return cmd_id; } tcmu_cmd->cmd_id = cmd_id; pr_debug("allocated cmd %u for dev %s tmo %lu\n", tcmu_cmd->cmd_id, udev->name, tmo / MSEC_PER_SEC); setup_timer: if (!tmo) return 0; tcmu_cmd->deadline = round_jiffies_up(jiffies + msecs_to_jiffies(tmo)); mod_timer(timer, tcmu_cmd->deadline); return 0; } static int add_to_cmdr_queue(struct tcmu_cmd *tcmu_cmd) { struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; unsigned int tmo; int ret; /* * For backwards compat if qfull_time_out is not set use * cmd_time_out and if that's not set use the default time out. */ if (!udev->qfull_time_out) return -ETIMEDOUT; else if (udev->qfull_time_out > 0) tmo = udev->qfull_time_out; else if (udev->cmd_time_out) tmo = udev->cmd_time_out; else tmo = TCMU_TIME_OUT; ret = tcmu_setup_cmd_timer(tcmu_cmd, tmo, &udev->qfull_timer); if (ret) return ret; list_add_tail(&tcmu_cmd->cmdr_queue_entry, &udev->cmdr_queue); pr_debug("adding cmd %u on dev %s to ring space wait queue\n", tcmu_cmd->cmd_id, udev->name); return 0; } /** * queue_cmd_ring - queue cmd to ring or internally * @tcmu_cmd: cmd to queue * @scsi_err: TCM error code if failure (-1) returned. * * Returns: * -1 we cannot queue internally or to the ring. * 0 success * 1 internally queued to wait for ring memory to free. */ static sense_reason_t queue_cmd_ring(struct tcmu_cmd *tcmu_cmd, int *scsi_err) { struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; struct se_cmd *se_cmd = tcmu_cmd->se_cmd; size_t base_command_size, command_size; struct tcmu_mailbox *mb; struct tcmu_cmd_entry *entry; struct iovec *iov; int iov_cnt, ret; uint32_t cmd_head; uint64_t cdb_off; bool copy_to_data_area; size_t data_length = tcmu_cmd_get_data_length(tcmu_cmd); *scsi_err = TCM_NO_SENSE; if (test_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags)) { *scsi_err = TCM_LUN_BUSY; return -1; } if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) { *scsi_err = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; return -1; } /* * Must be a certain minimum size for response sense info, but * also may be larger if the iov array is large. * * We prepare as many iovs as possbile for potential uses here, * because it's expensive to tell how many regions are freed in * the bitmap & global data pool, as the size calculated here * will only be used to do the checks. * * The size will be recalculated later as actually needed to save * cmd area memories. */ base_command_size = tcmu_cmd_get_base_cmd_size(tcmu_cmd->dbi_cnt); command_size = tcmu_cmd_get_cmd_size(tcmu_cmd, base_command_size); if (!list_empty(&udev->cmdr_queue)) goto queue; mb = udev->mb_addr; cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ if ((command_size > (udev->cmdr_size / 2)) || data_length > udev->data_size) { pr_warn("TCMU: Request of size %zu/%zu is too big for %u/%zu " "cmd ring/data area\n", command_size, data_length, udev->cmdr_size, udev->data_size); *scsi_err = TCM_INVALID_CDB_FIELD; return -1; } if (!is_ring_space_avail(udev, tcmu_cmd, command_size, data_length)) { /* * Don't leave commands partially setup because the unmap * thread might need the blocks to make forward progress. */ tcmu_cmd_free_data(tcmu_cmd, tcmu_cmd->dbi_cur); tcmu_cmd_reset_dbi_cur(tcmu_cmd); goto queue; } /* Insert a PAD if end-of-ring space is too small */ if (head_to_end(cmd_head, udev->cmdr_size) < command_size) { size_t pad_size = head_to_end(cmd_head, udev->cmdr_size); entry = (void *) mb + CMDR_OFF + cmd_head; tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_PAD); tcmu_hdr_set_len(&entry->hdr.len_op, pad_size); entry->hdr.cmd_id = 0; /* not used for PAD */ entry->hdr.kflags = 0; entry->hdr.uflags = 0; tcmu_flush_dcache_range(entry, sizeof(*entry)); UPDATE_HEAD(mb->cmd_head, pad_size, udev->cmdr_size); tcmu_flush_dcache_range(mb, sizeof(*mb)); cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ WARN_ON(cmd_head != 0); } entry = (void *) mb + CMDR_OFF + cmd_head; memset(entry, 0, command_size); tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_CMD); /* Handle allocating space from the data area */ tcmu_cmd_reset_dbi_cur(tcmu_cmd); iov = &entry->req.iov[0]; iov_cnt = 0; copy_to_data_area = (se_cmd->data_direction == DMA_TO_DEVICE || se_cmd->se_cmd_flags & SCF_BIDI); scatter_data_area(udev, tcmu_cmd, se_cmd->t_data_sg, se_cmd->t_data_nents, &iov, &iov_cnt, copy_to_data_area); entry->req.iov_cnt = iov_cnt; /* Handle BIDI commands */ iov_cnt = 0; if (se_cmd->se_cmd_flags & SCF_BIDI) { iov++; scatter_data_area(udev, tcmu_cmd, se_cmd->t_bidi_data_sg, se_cmd->t_bidi_data_nents, &iov, &iov_cnt, false); } entry->req.iov_bidi_cnt = iov_cnt; ret = tcmu_setup_cmd_timer(tcmu_cmd, udev->cmd_time_out, &udev->cmd_timer); if (ret) { tcmu_cmd_free_data(tcmu_cmd, tcmu_cmd->dbi_cnt); *scsi_err = TCM_OUT_OF_RESOURCES; return -1; } entry->hdr.cmd_id = tcmu_cmd->cmd_id; /* * Recalaulate the command's base size and size according * to the actual needs */ base_command_size = tcmu_cmd_get_base_cmd_size(entry->req.iov_cnt + entry->req.iov_bidi_cnt); command_size = tcmu_cmd_get_cmd_size(tcmu_cmd, base_command_size); tcmu_hdr_set_len(&entry->hdr.len_op, command_size); /* All offsets relative to mb_addr, not start of entry! */ cdb_off = CMDR_OFF + cmd_head + base_command_size; memcpy((void *) mb + cdb_off, se_cmd->t_task_cdb, scsi_command_size(se_cmd->t_task_cdb)); entry->req.cdb_off = cdb_off; tcmu_flush_dcache_range(entry, sizeof(*entry)); UPDATE_HEAD(mb->cmd_head, command_size, udev->cmdr_size); tcmu_flush_dcache_range(mb, sizeof(*mb)); /* TODO: only if FLUSH and FUA? */ uio_event_notify(&udev->uio_info); return 0; queue: if (add_to_cmdr_queue(tcmu_cmd)) { *scsi_err = TCM_OUT_OF_RESOURCES; return -1; } return 1; } static sense_reason_t tcmu_queue_cmd(struct se_cmd *se_cmd) { struct se_device *se_dev = se_cmd->se_dev; struct tcmu_dev *udev = TCMU_DEV(se_dev); struct tcmu_cmd *tcmu_cmd; sense_reason_t scsi_ret; int ret; tcmu_cmd = tcmu_alloc_cmd(se_cmd); if (!tcmu_cmd) return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; mutex_lock(&udev->cmdr_lock); ret = queue_cmd_ring(tcmu_cmd, &scsi_ret); mutex_unlock(&udev->cmdr_lock); if (ret < 0) tcmu_free_cmd(tcmu_cmd); return scsi_ret; } static void tcmu_handle_completion(struct tcmu_cmd *cmd, struct tcmu_cmd_entry *entry) { struct se_cmd *se_cmd = cmd->se_cmd; struct tcmu_dev *udev = cmd->tcmu_dev; bool read_len_valid = false; uint32_t read_len = se_cmd->data_length; /* * cmd has been completed already from timeout, just reclaim * data area space and free cmd */ if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) goto out; tcmu_cmd_reset_dbi_cur(cmd); if (entry->hdr.uflags & TCMU_UFLAG_UNKNOWN_OP) { pr_warn("TCMU: Userspace set UNKNOWN_OP flag on se_cmd %p\n", cmd->se_cmd); entry->rsp.scsi_status = SAM_STAT_CHECK_CONDITION; goto done; } if (se_cmd->data_direction == DMA_FROM_DEVICE && (entry->hdr.uflags & TCMU_UFLAG_READ_LEN) && entry->rsp.read_len) { read_len_valid = true; if (entry->rsp.read_len < read_len) read_len = entry->rsp.read_len; } if (entry->rsp.scsi_status == SAM_STAT_CHECK_CONDITION) { transport_copy_sense_to_cmd(se_cmd, entry->rsp.sense_buffer); if (!read_len_valid ) goto done; else se_cmd->se_cmd_flags |= SCF_TREAT_READ_AS_NORMAL; } if (se_cmd->se_cmd_flags & SCF_BIDI) { /* Get Data-In buffer before clean up */ gather_data_area(udev, cmd, true, read_len); } else if (se_cmd->data_direction == DMA_FROM_DEVICE) { gather_data_area(udev, cmd, false, read_len); } else if (se_cmd->data_direction == DMA_TO_DEVICE) { /* TODO: */ } else if (se_cmd->data_direction != DMA_NONE) { pr_warn("TCMU: data direction was %d!\n", se_cmd->data_direction); } done: if (read_len_valid) { pr_debug("read_len = %d\n", read_len); target_complete_cmd_with_length(cmd->se_cmd, entry->rsp.scsi_status, read_len); } else target_complete_cmd(cmd->se_cmd, entry->rsp.scsi_status); out: cmd->se_cmd = NULL; tcmu_cmd_free_data(cmd, cmd->dbi_cnt); tcmu_free_cmd(cmd); } static unsigned int tcmu_handle_completions(struct tcmu_dev *udev) { struct tcmu_mailbox *mb; int handled = 0; if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) { pr_err("ring broken, not handling completions\n"); return 0; } mb = udev->mb_addr; tcmu_flush_dcache_range(mb, sizeof(*mb)); while (udev->cmdr_last_cleaned != READ_ONCE(mb->cmd_tail)) { struct tcmu_cmd_entry *entry = (void *) mb + CMDR_OFF + udev->cmdr_last_cleaned; struct tcmu_cmd *cmd; tcmu_flush_dcache_range(entry, sizeof(*entry)); if (tcmu_hdr_get_op(entry->hdr.len_op) == TCMU_OP_PAD) { UPDATE_HEAD(udev->cmdr_last_cleaned, tcmu_hdr_get_len(entry->hdr.len_op), udev->cmdr_size); continue; } WARN_ON(tcmu_hdr_get_op(entry->hdr.len_op) != TCMU_OP_CMD); cmd = idr_remove(&udev->commands, entry->hdr.cmd_id); if (!cmd) { pr_err("cmd_id %u not found, ring is broken\n", entry->hdr.cmd_id); set_bit(TCMU_DEV_BIT_BROKEN, &udev->flags); break; } tcmu_handle_completion(cmd, entry); UPDATE_HEAD(udev->cmdr_last_cleaned, tcmu_hdr_get_len(entry->hdr.len_op), udev->cmdr_size); handled++; } if (mb->cmd_tail == mb->cmd_head) { /* no more pending commands */ del_timer(&udev->cmd_timer); if (list_empty(&udev->cmdr_queue)) { /* * no more pending or waiting commands so try to * reclaim blocks if needed. */ if (atomic_read(&global_db_count) > tcmu_global_max_blocks) schedule_delayed_work(&tcmu_unmap_work, 0); } } return handled; } static int tcmu_check_expired_cmd(int id, void *p, void *data) { struct tcmu_cmd *cmd = p; struct tcmu_dev *udev = cmd->tcmu_dev; u8 scsi_status; struct se_cmd *se_cmd; bool is_running; if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) return 0; if (!time_after(jiffies, cmd->deadline)) return 0; is_running = list_empty(&cmd->cmdr_queue_entry); se_cmd = cmd->se_cmd; if (is_running) { /* * If cmd_time_out is disabled but qfull is set deadline * will only reflect the qfull timeout. Ignore it. */ if (!udev->cmd_time_out) return 0; set_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags); /* * target_complete_cmd will translate this to LUN COMM FAILURE */ scsi_status = SAM_STAT_CHECK_CONDITION; } else { list_del_init(&cmd->cmdr_queue_entry); idr_remove(&udev->commands, id); tcmu_free_cmd(cmd); scsi_status = SAM_STAT_TASK_SET_FULL; } pr_debug("Timing out cmd %u on dev %s that is %s.\n", id, udev->name, is_running ? "inflight" : "queued"); target_complete_cmd(se_cmd, scsi_status); return 0; } static void tcmu_device_timedout(struct tcmu_dev *udev) { spin_lock(&timed_out_udevs_lock); if (list_empty(&udev->timedout_entry)) list_add_tail(&udev->timedout_entry, &timed_out_udevs); spin_unlock(&timed_out_udevs_lock); schedule_delayed_work(&tcmu_unmap_work, 0); } static void tcmu_cmd_timedout(struct timer_list *t) { struct tcmu_dev *udev = from_timer(udev, t, cmd_timer); pr_debug("%s cmd timeout has expired\n", udev->name); tcmu_device_timedout(udev); } static void tcmu_qfull_timedout(struct timer_list *t) { struct tcmu_dev *udev = from_timer(udev, t, qfull_timer); pr_debug("%s qfull timeout has expired\n", udev->name); tcmu_device_timedout(udev); } static int tcmu_attach_hba(struct se_hba *hba, u32 host_id) { struct tcmu_hba *tcmu_hba; tcmu_hba = kzalloc(sizeof(struct tcmu_hba), GFP_KERNEL); if (!tcmu_hba) return -ENOMEM; tcmu_hba->host_id = host_id; hba->hba_ptr = tcmu_hba; return 0; } static void tcmu_detach_hba(struct se_hba *hba) { kfree(hba->hba_ptr); hba->hba_ptr = NULL; } static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name) { struct tcmu_dev *udev; udev = kzalloc(sizeof(struct tcmu_dev), GFP_KERNEL); if (!udev) return NULL; kref_init(&udev->kref); udev->name = kstrdup(name, GFP_KERNEL); if (!udev->name) { kfree(udev); return NULL; } udev->hba = hba; udev->cmd_time_out = TCMU_TIME_OUT; udev->qfull_time_out = -1; udev->max_blocks = DATA_BLOCK_BITS_DEF; mutex_init(&udev->cmdr_lock); INIT_LIST_HEAD(&udev->node); INIT_LIST_HEAD(&udev->timedout_entry); INIT_LIST_HEAD(&udev->cmdr_queue); idr_init(&udev->commands); timer_setup(&udev->qfull_timer, tcmu_qfull_timedout, 0); timer_setup(&udev->cmd_timer, tcmu_cmd_timedout, 0); INIT_RADIX_TREE(&udev->data_blocks, GFP_KERNEL); return &udev->se_dev; } static bool run_cmdr_queue(struct tcmu_dev *udev, bool fail) { struct tcmu_cmd *tcmu_cmd, *tmp_cmd; LIST_HEAD(cmds); bool drained = true; sense_reason_t scsi_ret; int ret; if (list_empty(&udev->cmdr_queue)) return true; pr_debug("running %s's cmdr queue forcefail %d\n", udev->name, fail); list_splice_init(&udev->cmdr_queue, &cmds); list_for_each_entry_safe(tcmu_cmd, tmp_cmd, &cmds, cmdr_queue_entry) { list_del_init(&tcmu_cmd->cmdr_queue_entry); pr_debug("removing cmd %u on dev %s from queue\n", tcmu_cmd->cmd_id, udev->name); if (fail) { idr_remove(&udev->commands, tcmu_cmd->cmd_id); /* * We were not able to even start the command, so * fail with busy to allow a retry in case runner * was only temporarily down. If the device is being * removed then LIO core will do the right thing and * fail the retry. */ target_complete_cmd(tcmu_cmd->se_cmd, SAM_STAT_BUSY); tcmu_free_cmd(tcmu_cmd); continue; } ret = queue_cmd_ring(tcmu_cmd, &scsi_ret); if (ret < 0) { pr_debug("cmd %u on dev %s failed with %u\n", tcmu_cmd->cmd_id, udev->name, scsi_ret); idr_remove(&udev->commands, tcmu_cmd->cmd_id); /* * Ignore scsi_ret for now. target_complete_cmd * drops it. */ target_complete_cmd(tcmu_cmd->se_cmd, SAM_STAT_CHECK_CONDITION); tcmu_free_cmd(tcmu_cmd); } else if (ret > 0) { pr_debug("ran out of space during cmdr queue run\n"); /* * cmd was requeued, so just put all cmds back in * the queue */ list_splice_tail(&cmds, &udev->cmdr_queue); drained = false; goto done; } } if (list_empty(&udev->cmdr_queue)) del_timer(&udev->qfull_timer); done: return drained; } static int tcmu_irqcontrol(struct uio_info *info, s32 irq_on) { struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); mutex_lock(&udev->cmdr_lock); tcmu_handle_completions(udev); run_cmdr_queue(udev, false); mutex_unlock(&udev->cmdr_lock); return 0; } /* * mmap code from uio.c. Copied here because we want to hook mmap() * and this stuff must come along. */ static int tcmu_find_mem_index(struct vm_area_struct *vma) { struct tcmu_dev *udev = vma->vm_private_data; struct uio_info *info = &udev->uio_info; if (vma->vm_pgoff < MAX_UIO_MAPS) { if (info->mem[vma->vm_pgoff].size == 0) return -1; return (int)vma->vm_pgoff; } return -1; } static struct page *tcmu_try_get_block_page(struct tcmu_dev *udev, uint32_t dbi) { struct page *page; mutex_lock(&udev->cmdr_lock); page = tcmu_get_block_page(udev, dbi); if (likely(page)) { mutex_unlock(&udev->cmdr_lock); return page; } /* * Userspace messed up and passed in a address not in the * data iov passed to it. */ pr_err("Invalid addr to data block mapping (dbi %u) on device %s\n", dbi, udev->name); page = NULL; mutex_unlock(&udev->cmdr_lock); return page; } static vm_fault_t tcmu_vma_fault(struct vm_fault *vmf) { struct tcmu_dev *udev = vmf->vma->vm_private_data; struct uio_info *info = &udev->uio_info; struct page *page; unsigned long offset; void *addr; int mi = tcmu_find_mem_index(vmf->vma); if (mi < 0) return VM_FAULT_SIGBUS; /* * We need to subtract mi because userspace uses offset = N*PAGE_SIZE * to use mem[N]. */ offset = (vmf->pgoff - mi) << PAGE_SHIFT; if (offset < udev->data_off) { /* For the vmalloc()ed cmd area pages */ addr = (void *)(unsigned long)info->mem[mi].addr + offset; page = vmalloc_to_page(addr); } else { uint32_t dbi; /* For the dynamically growing data area pages */ dbi = (offset - udev->data_off) / DATA_BLOCK_SIZE; page = tcmu_try_get_block_page(udev, dbi); if (!page) return VM_FAULT_SIGBUS; } get_page(page); vmf->page = page; return 0; } static const struct vm_operations_struct tcmu_vm_ops = { .fault = tcmu_vma_fault, }; static int tcmu_mmap(struct uio_info *info, struct vm_area_struct *vma) { struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; vma->vm_ops = &tcmu_vm_ops; vma->vm_private_data = udev; /* Ensure the mmap is exactly the right size */ if (vma_pages(vma) != (udev->ring_size >> PAGE_SHIFT)) return -EINVAL; return 0; } static int tcmu_open(struct uio_info *info, struct inode *inode) { struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); /* O_EXCL not supported for char devs, so fake it? */ if (test_and_set_bit(TCMU_DEV_BIT_OPEN, &udev->flags)) return -EBUSY; udev->inode = inode; kref_get(&udev->kref); pr_debug("open\n"); return 0; } static void tcmu_dev_call_rcu(struct rcu_head *p) { struct se_device *dev = container_of(p, struct se_device, rcu_head); struct tcmu_dev *udev = TCMU_DEV(dev); kfree(udev->uio_info.name); kfree(udev->name); kfree(udev); } static int tcmu_check_and_free_pending_cmd(struct tcmu_cmd *cmd) { if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) { kmem_cache_free(tcmu_cmd_cache, cmd); return 0; } return -EINVAL; } static void tcmu_blocks_release(struct radix_tree_root *blocks, int start, int end) { int i; struct page *page; for (i = start; i < end; i++) { page = radix_tree_delete(blocks, i); if (page) { __free_page(page); atomic_dec(&global_db_count); } } } static void tcmu_dev_kref_release(struct kref *kref) { struct tcmu_dev *udev = container_of(kref, struct tcmu_dev, kref); struct se_device *dev = &udev->se_dev; struct tcmu_cmd *cmd; bool all_expired = true; int i; vfree(udev->mb_addr); udev->mb_addr = NULL; spin_lock_bh(&timed_out_udevs_lock); if (!list_empty(&udev->timedout_entry)) list_del(&udev->timedout_entry); spin_unlock_bh(&timed_out_udevs_lock); /* Upper layer should drain all requests before calling this */ mutex_lock(&udev->cmdr_lock); idr_for_each_entry(&udev->commands, cmd, i) { if (tcmu_check_and_free_pending_cmd(cmd) != 0) all_expired = false; } idr_destroy(&udev->commands); WARN_ON(!all_expired); tcmu_blocks_release(&udev->data_blocks, 0, udev->dbi_max + 1); kfree(udev->data_bitmap); mutex_unlock(&udev->cmdr_lock); call_rcu(&dev->rcu_head, tcmu_dev_call_rcu); } static int tcmu_release(struct uio_info *info, struct inode *inode) { struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); clear_bit(TCMU_DEV_BIT_OPEN, &udev->flags); pr_debug("close\n"); /* release ref from open */ kref_put(&udev->kref, tcmu_dev_kref_release); return 0; } static int tcmu_init_genl_cmd_reply(struct tcmu_dev *udev, int cmd) { struct tcmu_nl_cmd *nl_cmd = &udev->curr_nl_cmd; if (!tcmu_kern_cmd_reply_supported) return 0; if (udev->nl_reply_supported <= 0) return 0; mutex_lock(&tcmu_nl_cmd_mutex); if (tcmu_netlink_blocked) { mutex_unlock(&tcmu_nl_cmd_mutex); pr_warn("Failing nl cmd %d on %s. Interface is blocked.\n", cmd, udev->name); return -EAGAIN; } if (nl_cmd->cmd != TCMU_CMD_UNSPEC) { mutex_unlock(&tcmu_nl_cmd_mutex); pr_warn("netlink cmd %d already executing on %s\n", nl_cmd->cmd, udev->name); return -EBUSY; } memset(nl_cmd, 0, sizeof(*nl_cmd)); nl_cmd->cmd = cmd; nl_cmd->udev = udev; init_completion(&nl_cmd->complete); INIT_LIST_HEAD(&nl_cmd->nl_list); list_add_tail(&nl_cmd->nl_list, &tcmu_nl_cmd_list); mutex_unlock(&tcmu_nl_cmd_mutex); return 0; } static int tcmu_wait_genl_cmd_reply(struct tcmu_dev *udev) { struct tcmu_nl_cmd *nl_cmd = &udev->curr_nl_cmd; int ret; if (!tcmu_kern_cmd_reply_supported) return 0; if (udev->nl_reply_supported <= 0) return 0; pr_debug("sleeping for nl reply\n"); wait_for_completion(&nl_cmd->complete); mutex_lock(&tcmu_nl_cmd_mutex); nl_cmd->cmd = TCMU_CMD_UNSPEC; ret = nl_cmd->status; mutex_unlock(&tcmu_nl_cmd_mutex); return ret; } static int tcmu_netlink_event_init(struct tcmu_dev *udev, enum tcmu_genl_cmd cmd, struct sk_buff **buf, void **hdr) { struct sk_buff *skb; void *msg_header; int ret = -ENOMEM; skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) return ret; msg_header = genlmsg_put(skb, 0, 0, &tcmu_genl_family, 0, cmd); if (!msg_header) goto free_skb; ret = nla_put_string(skb, TCMU_ATTR_DEVICE, udev->uio_info.name); if (ret < 0) goto free_skb; ret = nla_put_u32(skb, TCMU_ATTR_MINOR, udev->uio_info.uio_dev->minor); if (ret < 0) goto free_skb; ret = nla_put_u32(skb, TCMU_ATTR_DEVICE_ID, udev->se_dev.dev_index); if (ret < 0) goto free_skb; *buf = skb; *hdr = msg_header; return ret; free_skb: nlmsg_free(skb); return ret; } static int tcmu_netlink_event_send(struct tcmu_dev *udev, enum tcmu_genl_cmd cmd, struct sk_buff *skb, void *msg_header) { int ret; genlmsg_end(skb, msg_header); ret = tcmu_init_genl_cmd_reply(udev, cmd); if (ret) { nlmsg_free(skb); return ret; } ret = genlmsg_multicast_allns(&tcmu_genl_family, skb, 0, TCMU_MCGRP_CONFIG, GFP_KERNEL); /* We don't care if no one is listening */ if (ret == -ESRCH) ret = 0; if (!ret) ret = tcmu_wait_genl_cmd_reply(udev); return ret; } static int tcmu_send_dev_add_event(struct tcmu_dev *udev) { struct sk_buff *skb = NULL; void *msg_header = NULL; int ret = 0; ret = tcmu_netlink_event_init(udev, TCMU_CMD_ADDED_DEVICE, &skb, &msg_header); if (ret < 0) return ret; return tcmu_netlink_event_send(udev, TCMU_CMD_ADDED_DEVICE, skb, msg_header); } static int tcmu_send_dev_remove_event(struct tcmu_dev *udev) { struct sk_buff *skb = NULL; void *msg_header = NULL; int ret = 0; ret = tcmu_netlink_event_init(udev, TCMU_CMD_REMOVED_DEVICE, &skb, &msg_header); if (ret < 0) return ret; return tcmu_netlink_event_send(udev, TCMU_CMD_REMOVED_DEVICE, skb, msg_header); } static int tcmu_update_uio_info(struct tcmu_dev *udev) { struct tcmu_hba *hba = udev->hba->hba_ptr; struct uio_info *info; size_t size, used; char *str; info = &udev->uio_info; size = snprintf(NULL, 0, "tcm-user/%u/%s/%s", hba->host_id, udev->name, udev->dev_config); size += 1; /* for \0 */ str = kmalloc(size, GFP_KERNEL); if (!str) return -ENOMEM; used = snprintf(str, size, "tcm-user/%u/%s", hba->host_id, udev->name); if (udev->dev_config[0]) snprintf(str + used, size - used, "/%s", udev->dev_config); /* If the old string exists, free it */ kfree(info->name); info->name = str; return 0; } static int tcmu_configure_device(struct se_device *dev) { struct tcmu_dev *udev = TCMU_DEV(dev); struct uio_info *info; struct tcmu_mailbox *mb; int ret = 0; ret = tcmu_update_uio_info(udev); if (ret) return ret; info = &udev->uio_info; mutex_lock(&udev->cmdr_lock); udev->data_bitmap = kcalloc(BITS_TO_LONGS(udev->max_blocks), sizeof(unsigned long), GFP_KERNEL); mutex_unlock(&udev->cmdr_lock); if (!udev->data_bitmap) { ret = -ENOMEM; goto err_bitmap_alloc; } udev->mb_addr = vzalloc(CMDR_SIZE); if (!udev->mb_addr) { ret = -ENOMEM; goto err_vzalloc; } /* mailbox fits in first part of CMDR space */ udev->cmdr_size = CMDR_SIZE - CMDR_OFF; udev->data_off = CMDR_SIZE; udev->data_size = udev->max_blocks * DATA_BLOCK_SIZE; udev->dbi_thresh = 0; /* Default in Idle state */ /* Initialise the mailbox of the ring buffer */ mb = udev->mb_addr; mb->version = TCMU_MAILBOX_VERSION; mb->flags = TCMU_MAILBOX_FLAG_CAP_OOOC | TCMU_MAILBOX_FLAG_CAP_READ_LEN; mb->cmdr_off = CMDR_OFF; mb->cmdr_size = udev->cmdr_size; WARN_ON(!PAGE_ALIGNED(udev->data_off)); WARN_ON(udev->data_size % PAGE_SIZE); WARN_ON(udev->data_size % DATA_BLOCK_SIZE); info->version = __stringify(TCMU_MAILBOX_VERSION); info->mem[0].name = "tcm-user command & data buffer"; info->mem[0].addr = (phys_addr_t)(uintptr_t)udev->mb_addr; info->mem[0].size = udev->ring_size = udev->data_size + CMDR_SIZE; info->mem[0].memtype = UIO_MEM_NONE; info->irqcontrol = tcmu_irqcontrol; info->irq = UIO_IRQ_CUSTOM; info->mmap = tcmu_mmap; info->open = tcmu_open; info->release = tcmu_release; ret = uio_register_device(tcmu_root_device, info); if (ret) goto err_register; /* User can set hw_block_size before enable the device */ if (dev->dev_attrib.hw_block_size == 0) dev->dev_attrib.hw_block_size = 512; /* Other attributes can be configured in userspace */ if (!dev->dev_attrib.hw_max_sectors) dev->dev_attrib.hw_max_sectors = 128; if (!dev->dev_attrib.emulate_write_cache) dev->dev_attrib.emulate_write_cache = 0; dev->dev_attrib.hw_queue_depth = 128; /* If user didn't explicitly disable netlink reply support, use * module scope setting. */ if (udev->nl_reply_supported >= 0) udev->nl_reply_supported = tcmu_kern_cmd_reply_supported; /* * Get a ref incase userspace does a close on the uio device before * LIO has initiated tcmu_free_device. */ kref_get(&udev->kref); ret = tcmu_send_dev_add_event(udev); if (ret) goto err_netlink; mutex_lock(&root_udev_mutex); list_add(&udev->node, &root_udev); mutex_unlock(&root_udev_mutex); return 0; err_netlink: kref_put(&udev->kref, tcmu_dev_kref_release); uio_unregister_device(&udev->uio_info); err_register: vfree(udev->mb_addr); udev->mb_addr = NULL; err_vzalloc: kfree(udev->data_bitmap); udev->data_bitmap = NULL; err_bitmap_alloc: kfree(info->name); info->name = NULL; return ret; } static void tcmu_free_device(struct se_device *dev) { struct tcmu_dev *udev = TCMU_DEV(dev); /* release ref from init */ kref_put(&udev->kref, tcmu_dev_kref_release); } static void tcmu_destroy_device(struct se_device *dev) { struct tcmu_dev *udev = TCMU_DEV(dev); del_timer_sync(&udev->cmd_timer); del_timer_sync(&udev->qfull_timer); mutex_lock(&root_udev_mutex); list_del(&udev->node); mutex_unlock(&root_udev_mutex); tcmu_send_dev_remove_event(udev); uio_unregister_device(&udev->uio_info); /* release ref from configure */ kref_put(&udev->kref, tcmu_dev_kref_release); } static void tcmu_unblock_dev(struct tcmu_dev *udev) { mutex_lock(&udev->cmdr_lock); clear_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags); mutex_unlock(&udev->cmdr_lock); } static void tcmu_block_dev(struct tcmu_dev *udev) { mutex_lock(&udev->cmdr_lock); if (test_and_set_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags)) goto unlock; /* complete IO that has executed successfully */ tcmu_handle_completions(udev); /* fail IO waiting to be queued */ run_cmdr_queue(udev, true); unlock: mutex_unlock(&udev->cmdr_lock); } static void tcmu_reset_ring(struct tcmu_dev *udev, u8 err_level) { struct tcmu_mailbox *mb; struct tcmu_cmd *cmd; int i; mutex_lock(&udev->cmdr_lock); idr_for_each_entry(&udev->commands, cmd, i) { if (!list_empty(&cmd->cmdr_queue_entry)) continue; pr_debug("removing cmd %u on dev %s from ring (is expired %d)\n", cmd->cmd_id, udev->name, test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)); idr_remove(&udev->commands, i); if (!test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) { if (err_level == 1) { /* * Userspace was not able to start the * command or it is retryable. */ target_complete_cmd(cmd->se_cmd, SAM_STAT_BUSY); } else { /* hard failure */ target_complete_cmd(cmd->se_cmd, SAM_STAT_CHECK_CONDITION); } } tcmu_cmd_free_data(cmd, cmd->dbi_cnt); tcmu_free_cmd(cmd); } mb = udev->mb_addr; tcmu_flush_dcache_range(mb, sizeof(*mb)); pr_debug("mb last %u head %u tail %u\n", udev->cmdr_last_cleaned, mb->cmd_tail, mb->cmd_head); udev->cmdr_last_cleaned = 0; mb->cmd_tail = 0; mb->cmd_head = 0; tcmu_flush_dcache_range(mb, sizeof(*mb)); del_timer(&udev->cmd_timer); mutex_unlock(&udev->cmdr_lock); } enum { Opt_dev_config, Opt_dev_size, Opt_hw_block_size, Opt_hw_max_sectors, Opt_nl_reply_supported, Opt_max_data_area_mb, Opt_err, }; static match_table_t tokens = { {Opt_dev_config, "dev_config=%s"}, {Opt_dev_size, "dev_size=%s"}, {Opt_hw_block_size, "hw_block_size=%d"}, {Opt_hw_max_sectors, "hw_max_sectors=%d"}, {Opt_nl_reply_supported, "nl_reply_supported=%d"}, {Opt_max_data_area_mb, "max_data_area_mb=%d"}, {Opt_err, NULL} }; static int tcmu_set_dev_attrib(substring_t *arg, u32 *dev_attrib) { int val, ret; ret = match_int(arg, &val); if (ret < 0) { pr_err("match_int() failed for dev attrib. Error %d.\n", ret); return ret; } if (val <= 0) { pr_err("Invalid dev attrib value %d. Must be greater than zero.\n", val); return -EINVAL; } *dev_attrib = val; return 0; } static int tcmu_set_max_blocks_param(struct tcmu_dev *udev, substring_t *arg) { int val, ret; ret = match_int(arg, &val); if (ret < 0) { pr_err("match_int() failed for max_data_area_mb=. Error %d.\n", ret); return ret; } if (val <= 0) { pr_err("Invalid max_data_area %d.\n", val); return -EINVAL; } mutex_lock(&udev->cmdr_lock); if (udev->data_bitmap) { pr_err("Cannot set max_data_area_mb after it has been enabled.\n"); ret = -EINVAL; goto unlock; } udev->max_blocks = TCMU_MBS_TO_BLOCKS(val); if (udev->max_blocks > tcmu_global_max_blocks) { pr_err("%d is too large. Adjusting max_data_area_mb to global limit of %u\n", val, TCMU_BLOCKS_TO_MBS(tcmu_global_max_blocks)); udev->max_blocks = tcmu_global_max_blocks; } unlock: mutex_unlock(&udev->cmdr_lock); return ret; } static ssize_t tcmu_set_configfs_dev_params(struct se_device *dev, const char *page, ssize_t count) { struct tcmu_dev *udev = TCMU_DEV(dev); char *orig, *ptr, *opts; substring_t args[MAX_OPT_ARGS]; int ret = 0, 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_dev_config: if (match_strlcpy(udev->dev_config, &args[0], TCMU_CONFIG_LEN) == 0) { ret = -EINVAL; break; } pr_debug("TCMU: Referencing Path: %s\n", udev->dev_config); break; case Opt_dev_size: ret = match_u64(&args[0], &udev->dev_size); if (ret < 0) pr_err("match_u64() failed for dev_size=. Error %d.\n", ret); break; case Opt_hw_block_size: ret = tcmu_set_dev_attrib(&args[0], &(dev->dev_attrib.hw_block_size)); break; case Opt_hw_max_sectors: ret = tcmu_set_dev_attrib(&args[0], &(dev->dev_attrib.hw_max_sectors)); break; case Opt_nl_reply_supported: ret = match_int(&args[0], &udev->nl_reply_supported); if (ret < 0) pr_err("match_int() failed for nl_reply_supported=. Error %d.\n", ret); break; case Opt_max_data_area_mb: ret = tcmu_set_max_blocks_param(udev, &args[0]); break; default: break; } if (ret) break; } kfree(orig); return (!ret) ? count : ret; } static ssize_t tcmu_show_configfs_dev_params(struct se_device *dev, char *b) { struct tcmu_dev *udev = TCMU_DEV(dev); ssize_t bl = 0; bl = sprintf(b + bl, "Config: %s ", udev->dev_config[0] ? udev->dev_config : "NULL"); bl += sprintf(b + bl, "Size: %llu ", udev->dev_size); bl += sprintf(b + bl, "MaxDataAreaMB: %u\n", TCMU_BLOCKS_TO_MBS(udev->max_blocks)); return bl; } static sector_t tcmu_get_blocks(struct se_device *dev) { struct tcmu_dev *udev = TCMU_DEV(dev); return div_u64(udev->dev_size - dev->dev_attrib.block_size, dev->dev_attrib.block_size); } static sense_reason_t tcmu_parse_cdb(struct se_cmd *cmd) { return passthrough_parse_cdb(cmd, tcmu_queue_cmd); } static ssize_t tcmu_cmd_time_out_show(struct config_item *item, char *page) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); return snprintf(page, PAGE_SIZE, "%lu\n", udev->cmd_time_out / MSEC_PER_SEC); } static ssize_t tcmu_cmd_time_out_store(struct config_item *item, const char *page, size_t count) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = container_of(da->da_dev, struct tcmu_dev, se_dev); u32 val; int ret; if (da->da_dev->export_count) { pr_err("Unable to set tcmu cmd_time_out while exports exist\n"); return -EINVAL; } ret = kstrtou32(page, 0, &val); if (ret < 0) return ret; udev->cmd_time_out = val * MSEC_PER_SEC; return count; } CONFIGFS_ATTR(tcmu_, cmd_time_out); static ssize_t tcmu_qfull_time_out_show(struct config_item *item, char *page) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); return snprintf(page, PAGE_SIZE, "%ld\n", udev->qfull_time_out <= 0 ? udev->qfull_time_out : udev->qfull_time_out / MSEC_PER_SEC); } static ssize_t tcmu_qfull_time_out_store(struct config_item *item, const char *page, size_t count) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); s32 val; int ret; ret = kstrtos32(page, 0, &val); if (ret < 0) return ret; if (val >= 0) { udev->qfull_time_out = val * MSEC_PER_SEC; } else if (val == -1) { udev->qfull_time_out = val; } else { printk(KERN_ERR "Invalid qfull timeout value %d\n", val); return -EINVAL; } return count; } CONFIGFS_ATTR(tcmu_, qfull_time_out); static ssize_t tcmu_max_data_area_mb_show(struct config_item *item, char *page) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); return snprintf(page, PAGE_SIZE, "%u\n", TCMU_BLOCKS_TO_MBS(udev->max_blocks)); } CONFIGFS_ATTR_RO(tcmu_, max_data_area_mb); static ssize_t tcmu_dev_config_show(struct config_item *item, char *page) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); return snprintf(page, PAGE_SIZE, "%s\n", udev->dev_config); } static int tcmu_send_dev_config_event(struct tcmu_dev *udev, const char *reconfig_data) { struct sk_buff *skb = NULL; void *msg_header = NULL; int ret = 0; ret = tcmu_netlink_event_init(udev, TCMU_CMD_RECONFIG_DEVICE, &skb, &msg_header); if (ret < 0) return ret; ret = nla_put_string(skb, TCMU_ATTR_DEV_CFG, reconfig_data); if (ret < 0) { nlmsg_free(skb); return ret; } return tcmu_netlink_event_send(udev, TCMU_CMD_RECONFIG_DEVICE, skb, msg_header); } static ssize_t tcmu_dev_config_store(struct config_item *item, const char *page, size_t count) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); int ret, len; len = strlen(page); if (!len || len > TCMU_CONFIG_LEN - 1) return -EINVAL; /* Check if device has been configured before */ if (target_dev_configured(&udev->se_dev)) { ret = tcmu_send_dev_config_event(udev, page); if (ret) { pr_err("Unable to reconfigure device\n"); return ret; } strlcpy(udev->dev_config, page, TCMU_CONFIG_LEN); ret = tcmu_update_uio_info(udev); if (ret) return ret; return count; } strlcpy(udev->dev_config, page, TCMU_CONFIG_LEN); return count; } CONFIGFS_ATTR(tcmu_, dev_config); static ssize_t tcmu_dev_size_show(struct config_item *item, char *page) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); return snprintf(page, PAGE_SIZE, "%llu\n", udev->dev_size); } static int tcmu_send_dev_size_event(struct tcmu_dev *udev, u64 size) { struct sk_buff *skb = NULL; void *msg_header = NULL; int ret = 0; ret = tcmu_netlink_event_init(udev, TCMU_CMD_RECONFIG_DEVICE, &skb, &msg_header); if (ret < 0) return ret; ret = nla_put_u64_64bit(skb, TCMU_ATTR_DEV_SIZE, size, TCMU_ATTR_PAD); if (ret < 0) { nlmsg_free(skb); return ret; } return tcmu_netlink_event_send(udev, TCMU_CMD_RECONFIG_DEVICE, skb, msg_header); } static ssize_t tcmu_dev_size_store(struct config_item *item, const char *page, size_t count) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); u64 val; int ret; ret = kstrtou64(page, 0, &val); if (ret < 0) return ret; /* Check if device has been configured before */ if (target_dev_configured(&udev->se_dev)) { ret = tcmu_send_dev_size_event(udev, val); if (ret) { pr_err("Unable to reconfigure device\n"); return ret; } } udev->dev_size = val; return count; } CONFIGFS_ATTR(tcmu_, dev_size); static ssize_t tcmu_nl_reply_supported_show(struct config_item *item, char *page) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); return snprintf(page, PAGE_SIZE, "%d\n", udev->nl_reply_supported); } static ssize_t tcmu_nl_reply_supported_store(struct config_item *item, const char *page, size_t count) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); s8 val; int ret; ret = kstrtos8(page, 0, &val); if (ret < 0) return ret; udev->nl_reply_supported = val; return count; } CONFIGFS_ATTR(tcmu_, nl_reply_supported); static ssize_t tcmu_emulate_write_cache_show(struct config_item *item, char *page) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); return snprintf(page, PAGE_SIZE, "%i\n", da->emulate_write_cache); } static int tcmu_send_emulate_write_cache(struct tcmu_dev *udev, u8 val) { struct sk_buff *skb = NULL; void *msg_header = NULL; int ret = 0; ret = tcmu_netlink_event_init(udev, TCMU_CMD_RECONFIG_DEVICE, &skb, &msg_header); if (ret < 0) return ret; ret = nla_put_u8(skb, TCMU_ATTR_WRITECACHE, val); if (ret < 0) { nlmsg_free(skb); return ret; } return tcmu_netlink_event_send(udev, TCMU_CMD_RECONFIG_DEVICE, skb, msg_header); } static ssize_t tcmu_emulate_write_cache_store(struct config_item *item, const char *page, size_t count) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); u8 val; int ret; ret = kstrtou8(page, 0, &val); if (ret < 0) return ret; /* Check if device has been configured before */ if (target_dev_configured(&udev->se_dev)) { ret = tcmu_send_emulate_write_cache(udev, val); if (ret) { pr_err("Unable to reconfigure device\n"); return ret; } } da->emulate_write_cache = val; return count; } CONFIGFS_ATTR(tcmu_, emulate_write_cache); static ssize_t tcmu_block_dev_show(struct config_item *item, char *page) { struct se_device *se_dev = container_of(to_config_group(item), struct se_device, dev_action_group); struct tcmu_dev *udev = TCMU_DEV(se_dev); if (test_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags)) return snprintf(page, PAGE_SIZE, "%s\n", "blocked"); else return snprintf(page, PAGE_SIZE, "%s\n", "unblocked"); } static ssize_t tcmu_block_dev_store(struct config_item *item, const char *page, size_t count) { struct se_device *se_dev = container_of(to_config_group(item), struct se_device, dev_action_group); struct tcmu_dev *udev = TCMU_DEV(se_dev); u8 val; int ret; if (!target_dev_configured(&udev->se_dev)) { pr_err("Device is not configured.\n"); return -EINVAL; } ret = kstrtou8(page, 0, &val); if (ret < 0) return ret; if (val > 1) { pr_err("Invalid block value %d\n", val); return -EINVAL; } if (!val) tcmu_unblock_dev(udev); else tcmu_block_dev(udev); return count; } CONFIGFS_ATTR(tcmu_, block_dev); static ssize_t tcmu_reset_ring_store(struct config_item *item, const char *page, size_t count) { struct se_device *se_dev = container_of(to_config_group(item), struct se_device, dev_action_group); struct tcmu_dev *udev = TCMU_DEV(se_dev); u8 val; int ret; if (!target_dev_configured(&udev->se_dev)) { pr_err("Device is not configured.\n"); return -EINVAL; } ret = kstrtou8(page, 0, &val); if (ret < 0) return ret; if (val != 1 && val != 2) { pr_err("Invalid reset ring value %d\n", val); return -EINVAL; } tcmu_reset_ring(udev, val); return count; } CONFIGFS_ATTR_WO(tcmu_, reset_ring); static struct configfs_attribute *tcmu_attrib_attrs[] = { &tcmu_attr_cmd_time_out, &tcmu_attr_qfull_time_out, &tcmu_attr_max_data_area_mb, &tcmu_attr_dev_config, &tcmu_attr_dev_size, &tcmu_attr_emulate_write_cache, &tcmu_attr_nl_reply_supported, NULL, }; static struct configfs_attribute **tcmu_attrs; static struct configfs_attribute *tcmu_action_attrs[] = { &tcmu_attr_block_dev, &tcmu_attr_reset_ring, NULL, }; static struct target_backend_ops tcmu_ops = { .name = "user", .owner = THIS_MODULE, .transport_flags = TRANSPORT_FLAG_PASSTHROUGH, .attach_hba = tcmu_attach_hba, .detach_hba = tcmu_detach_hba, .alloc_device = tcmu_alloc_device, .configure_device = tcmu_configure_device, .destroy_device = tcmu_destroy_device, .free_device = tcmu_free_device, .parse_cdb = tcmu_parse_cdb, .set_configfs_dev_params = tcmu_set_configfs_dev_params, .show_configfs_dev_params = tcmu_show_configfs_dev_params, .get_device_type = sbc_get_device_type, .get_blocks = tcmu_get_blocks, .tb_dev_action_attrs = tcmu_action_attrs, }; static void find_free_blocks(void) { struct tcmu_dev *udev; loff_t off; u32 start, end, block, total_freed = 0; if (atomic_read(&global_db_count) <= tcmu_global_max_blocks) return; mutex_lock(&root_udev_mutex); list_for_each_entry(udev, &root_udev, node) { mutex_lock(&udev->cmdr_lock); if (!target_dev_configured(&udev->se_dev)) { mutex_unlock(&udev->cmdr_lock); continue; } /* Try to complete the finished commands first */ tcmu_handle_completions(udev); /* Skip the udevs in idle */ if (!udev->dbi_thresh) { mutex_unlock(&udev->cmdr_lock); continue; } end = udev->dbi_max + 1; block = find_last_bit(udev->data_bitmap, end); if (block == udev->dbi_max) { /* * The last bit is dbi_max, so it is not possible * reclaim any blocks. */ mutex_unlock(&udev->cmdr_lock); continue; } else if (block == end) { /* The current udev will goto idle state */ udev->dbi_thresh = start = 0; udev->dbi_max = 0; } else { udev->dbi_thresh = start = block + 1; udev->dbi_max = block; } /* Here will truncate the data area from off */ off = udev->data_off + start * DATA_BLOCK_SIZE; unmap_mapping_range(udev->inode->i_mapping, off, 0, 1); /* Release the block pages */ tcmu_blocks_release(&udev->data_blocks, start, end); mutex_unlock(&udev->cmdr_lock); total_freed += end - start; pr_debug("Freed %u blocks (total %u) from %s.\n", end - start, total_freed, udev->name); } mutex_unlock(&root_udev_mutex); if (atomic_read(&global_db_count) > tcmu_global_max_blocks) schedule_delayed_work(&tcmu_unmap_work, msecs_to_jiffies(5000)); } static void check_timedout_devices(void) { struct tcmu_dev *udev, *tmp_dev; LIST_HEAD(devs); spin_lock_bh(&timed_out_udevs_lock); list_splice_init(&timed_out_udevs, &devs); list_for_each_entry_safe(udev, tmp_dev, &devs, timedout_entry) { list_del_init(&udev->timedout_entry); spin_unlock_bh(&timed_out_udevs_lock); mutex_lock(&udev->cmdr_lock); idr_for_each(&udev->commands, tcmu_check_expired_cmd, NULL); mutex_unlock(&udev->cmdr_lock); spin_lock_bh(&timed_out_udevs_lock); } spin_unlock_bh(&timed_out_udevs_lock); } static void tcmu_unmap_work_fn(struct work_struct *work) { check_timedout_devices(); find_free_blocks(); } static int __init tcmu_module_init(void) { int ret, i, k, len = 0; BUILD_BUG_ON((sizeof(struct tcmu_cmd_entry) % TCMU_OP_ALIGN_SIZE) != 0); INIT_DELAYED_WORK(&tcmu_unmap_work, tcmu_unmap_work_fn); tcmu_cmd_cache = kmem_cache_create("tcmu_cmd_cache", sizeof(struct tcmu_cmd), __alignof__(struct tcmu_cmd), 0, NULL); if (!tcmu_cmd_cache) return -ENOMEM; tcmu_root_device = root_device_register("tcm_user"); if (IS_ERR(tcmu_root_device)) { ret = PTR_ERR(tcmu_root_device); goto out_free_cache; } ret = genl_register_family(&tcmu_genl_family); if (ret < 0) { goto out_unreg_device; } for (i = 0; passthrough_attrib_attrs[i] != NULL; i++) { len += sizeof(struct configfs_attribute *); } for (i = 0; tcmu_attrib_attrs[i] != NULL; i++) { len += sizeof(struct configfs_attribute *); } len += sizeof(struct configfs_attribute *); tcmu_attrs = kzalloc(len, GFP_KERNEL); if (!tcmu_attrs) { ret = -ENOMEM; goto out_unreg_genl; } for (i = 0; passthrough_attrib_attrs[i] != NULL; i++) { tcmu_attrs[i] = passthrough_attrib_attrs[i]; } for (k = 0; tcmu_attrib_attrs[k] != NULL; k++) { tcmu_attrs[i] = tcmu_attrib_attrs[k]; i++; } tcmu_ops.tb_dev_attrib_attrs = tcmu_attrs; ret = transport_backend_register(&tcmu_ops); if (ret) goto out_attrs; return 0; out_attrs: kfree(tcmu_attrs); out_unreg_genl: genl_unregister_family(&tcmu_genl_family); out_unreg_device: root_device_unregister(tcmu_root_device); out_free_cache: kmem_cache_destroy(tcmu_cmd_cache); return ret; } static void __exit tcmu_module_exit(void) { cancel_delayed_work_sync(&tcmu_unmap_work); target_backend_unregister(&tcmu_ops); kfree(tcmu_attrs); genl_unregister_family(&tcmu_genl_family); root_device_unregister(tcmu_root_device); kmem_cache_destroy(tcmu_cmd_cache); } MODULE_DESCRIPTION("TCM USER subsystem plugin"); MODULE_AUTHOR("Shaohua Li <shli@kernel.org>"); MODULE_AUTHOR("Andy Grover <agrover@redhat.com>"); MODULE_LICENSE("GPL"); module_init(tcmu_module_init); module_exit(tcmu_module_exit);
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