--- /dev/null
+/*
+ * CXL Flash Device Driver
+ *
+ * Written by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>, IBM Corporation
+ * Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
+ *
+ * Copyright (C) 2015 IBM Corporation
+ *
+ * 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.
+ */
+
+#include <linux/delay.h>
+#include <linux/file.h>
+#include <linux/syscalls.h>
+#include <misc/cxl.h>
+#include <asm/unaligned.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_eh.h>
+#include <uapi/scsi/cxlflash_ioctl.h>
+
+#include "sislite.h"
+#include "common.h"
+#include "superpipe.h"
+
+struct cxlflash_global global;
+
+/**
+ * marshal_det_to_rele() - translate detach to release structure
+ * @detach: Destination structure for the translate/copy.
+ * @rele: Source structure from which to translate/copy.
+ */
+static void marshal_det_to_rele(struct dk_cxlflash_detach *detach,
+ struct dk_cxlflash_release *release)
+{
+ release->hdr = detach->hdr;
+ release->context_id = detach->context_id;
+}
+
+/**
+ * cxlflash_free_errpage() - frees resources associated with global error page
+ */
+void cxlflash_free_errpage(void)
+{
+
+ mutex_lock(&global.mutex);
+ if (global.err_page) {
+ __free_page(global.err_page);
+ global.err_page = NULL;
+ }
+ mutex_unlock(&global.mutex);
+}
+
+/**
+ * cxlflash_stop_term_user_contexts() - stops/terminates known user contexts
+ * @cfg: Internal structure associated with the host.
+ *
+ * When the host needs to go down, all users must be quiesced and their
+ * memory freed. This is accomplished by putting the contexts in error
+ * state which will notify the user and let them 'drive' the tear-down.
+ * Meanwhile, this routine camps until all user contexts have been removed.
+ */
+void cxlflash_stop_term_user_contexts(struct cxlflash_cfg *cfg)
+{
+ struct device *dev = &cfg->dev->dev;
+ int i, found;
+
+ cxlflash_mark_contexts_error(cfg);
+
+ while (true) {
+ found = false;
+
+ for (i = 0; i < MAX_CONTEXT; i++)
+ if (cfg->ctx_tbl[i]) {
+ found = true;
+ break;
+ }
+
+ if (!found && list_empty(&cfg->ctx_err_recovery))
+ return;
+
+ dev_dbg(dev, "%s: Wait for user contexts to quiesce...\n",
+ __func__);
+ wake_up_all(&cfg->limbo_waitq);
+ ssleep(1);
+ }
+}
+
+/**
+ * find_error_context() - locates a context by cookie on the error recovery list
+ * @cfg: Internal structure associated with the host.
+ * @rctxid: Desired context by id.
+ * @file: Desired context by file.
+ *
+ * Return: Found context on success, NULL on failure
+ */
+static struct ctx_info *find_error_context(struct cxlflash_cfg *cfg, u64 rctxid,
+ struct file *file)
+{
+ struct ctx_info *ctxi;
+
+ list_for_each_entry(ctxi, &cfg->ctx_err_recovery, list)
+ if ((ctxi->ctxid == rctxid) || (ctxi->file == file))
+ return ctxi;
+
+ return NULL;
+}
+
+/**
+ * get_context() - obtains a validated and locked context reference
+ * @cfg: Internal structure associated with the host.
+ * @rctxid: Desired context (raw, un-decoded format).
+ * @arg: LUN information or file associated with request.
+ * @ctx_ctrl: Control information to 'steer' desired lookup.
+ *
+ * NOTE: despite the name pid, in linux, current->pid actually refers
+ * to the lightweight process id (tid) and can change if the process is
+ * multi threaded. The tgid remains constant for the process and only changes
+ * when the process of fork. For all intents and purposes, think of tgid
+ * as a pid in the traditional sense.
+ *
+ * Return: Validated context on success, NULL on failure
+ */
+struct ctx_info *get_context(struct cxlflash_cfg *cfg, u64 rctxid,
+ void *arg, enum ctx_ctrl ctx_ctrl)
+{
+ struct device *dev = &cfg->dev->dev;
+ struct ctx_info *ctxi = NULL;
+ struct lun_access *lun_access = NULL;
+ struct file *file = NULL;
+ struct llun_info *lli = arg;
+ u64 ctxid = DECODE_CTXID(rctxid);
+ int rc;
+ pid_t pid = current->tgid, ctxpid = 0;
+
+ if (ctx_ctrl & CTX_CTRL_FILE) {
+ lli = NULL;
+ file = (struct file *)arg;
+ }
+
+ if (ctx_ctrl & CTX_CTRL_CLONE)
+ pid = current->parent->tgid;
+
+ if (likely(ctxid < MAX_CONTEXT)) {
+ while (true) {
+ rc = mutex_lock_interruptible(&cfg->ctx_tbl_list_mutex);
+ if (rc)
+ goto out;
+
+ ctxi = cfg->ctx_tbl[ctxid];
+ if (ctxi)
+ if ((file && (ctxi->file != file)) ||
+ (!file && (ctxi->ctxid != rctxid)))
+ ctxi = NULL;
+
+ if ((ctx_ctrl & CTX_CTRL_ERR) ||
+ (!ctxi && (ctx_ctrl & CTX_CTRL_ERR_FALLBACK)))
+ ctxi = find_error_context(cfg, rctxid, file);
+ if (!ctxi) {
+ mutex_unlock(&cfg->ctx_tbl_list_mutex);
+ goto out;
+ }
+
+ /*
+ * Need to acquire ownership of the context while still
+ * under the table/list lock to serialize with a remove
+ * thread. Use the 'try' to avoid stalling the
+ * table/list lock for a single context.
+ *
+ * Note that the lock order is:
+ *
+ * cfg->ctx_tbl_list_mutex -> ctxi->mutex
+ *
+ * Therefore release ctx_tbl_list_mutex before retrying.
+ */
+ rc = mutex_trylock(&ctxi->mutex);
+ mutex_unlock(&cfg->ctx_tbl_list_mutex);
+ if (rc)
+ break; /* got the context's lock! */
+ }
+
+ if (ctxi->unavail)
+ goto denied;
+
+ ctxpid = ctxi->pid;
+ if (likely(!(ctx_ctrl & CTX_CTRL_NOPID)))
+ if (pid != ctxpid)
+ goto denied;
+
+ if (lli) {
+ list_for_each_entry(lun_access, &ctxi->luns, list)
+ if (lun_access->lli == lli)
+ goto out;
+ goto denied;
+ }
+ }
+
+out:
+ dev_dbg(dev, "%s: rctxid=%016llX ctxinfo=%p ctxpid=%u pid=%u "
+ "ctx_ctrl=%u\n", __func__, rctxid, ctxi, ctxpid, pid,
+ ctx_ctrl);
+
+ return ctxi;
+
+denied:
+ mutex_unlock(&ctxi->mutex);
+ ctxi = NULL;
+ goto out;
+}
+
+/**
+ * put_context() - release a context that was retrieved from get_context()
+ * @ctxi: Context to release.
+ *
+ * For now, releasing the context equates to unlocking it's mutex.
+ */
+void put_context(struct ctx_info *ctxi)
+{
+ mutex_unlock(&ctxi->mutex);
+}
+
+/**
+ * afu_attach() - attach a context to the AFU
+ * @cfg: Internal structure associated with the host.
+ * @ctxi: Context to attach.
+ *
+ * Upon setting the context capabilities, they must be confirmed with
+ * a read back operation as the context might have been closed since
+ * the mailbox was unlocked. When this occurs, registration is failed.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int afu_attach(struct cxlflash_cfg *cfg, struct ctx_info *ctxi)
+{
+ struct device *dev = &cfg->dev->dev;
+ struct afu *afu = cfg->afu;
+ struct sisl_ctrl_map *ctrl_map = ctxi->ctrl_map;
+ int rc = 0;
+ u64 val;
+
+ /* Unlock cap and restrict user to read/write cmds in translated mode */
+ readq_be(&ctrl_map->mbox_r);
+ val = (SISL_CTX_CAP_READ_CMD | SISL_CTX_CAP_WRITE_CMD);
+ writeq_be(val, &ctrl_map->ctx_cap);
+ val = readq_be(&ctrl_map->ctx_cap);
+ if (val != (SISL_CTX_CAP_READ_CMD | SISL_CTX_CAP_WRITE_CMD)) {
+ dev_err(dev, "%s: ctx may be closed val=%016llX\n",
+ __func__, val);
+ rc = -EAGAIN;
+ goto out;
+ }
+
+ /* Set up MMIO registers pointing to the RHT */
+ writeq_be((u64)ctxi->rht_start, &ctrl_map->rht_start);
+ val = SISL_RHT_CNT_ID((u64)MAX_RHT_PER_CONTEXT, (u64)(afu->ctx_hndl));
+ writeq_be(val, &ctrl_map->rht_cnt_id);
+out:
+ dev_dbg(dev, "%s: returning rc=%d\n", __func__, rc);
+ return rc;
+}
+
+/**
+ * read_cap16() - issues a SCSI READ_CAP16 command
+ * @sdev: SCSI device associated with LUN.
+ * @lli: LUN destined for capacity request.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int read_cap16(struct scsi_device *sdev, struct llun_info *lli)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+ struct glun_info *gli = lli->parent;
+ u8 *cmd_buf = NULL;
+ u8 *scsi_cmd = NULL;
+ u8 *sense_buf = NULL;
+ int rc = 0;
+ int result = 0;
+ int retry_cnt = 0;
+ u32 tout = (MC_DISCOVERY_TIMEOUT * HZ);
+
+retry:
+ cmd_buf = kzalloc(CMD_BUFSIZE, GFP_KERNEL);
+ scsi_cmd = kzalloc(MAX_COMMAND_SIZE, GFP_KERNEL);
+ sense_buf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_KERNEL);
+ if (unlikely(!cmd_buf || !scsi_cmd || !sense_buf)) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ scsi_cmd[0] = SERVICE_ACTION_IN_16; /* read cap(16) */
+ scsi_cmd[1] = SAI_READ_CAPACITY_16; /* service action */
+ put_unaligned_be32(CMD_BUFSIZE, &scsi_cmd[10]);
+
+ dev_dbg(dev, "%s: %ssending cmd(0x%x)\n", __func__,
+ retry_cnt ? "re" : "", scsi_cmd[0]);
+
+ result = scsi_execute(sdev, scsi_cmd, DMA_FROM_DEVICE, cmd_buf,
+ CMD_BUFSIZE, sense_buf, tout, 5, 0, NULL);
+
+ if (driver_byte(result) == DRIVER_SENSE) {
+ result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
+ if (result & SAM_STAT_CHECK_CONDITION) {
+ struct scsi_sense_hdr sshdr;
+
+ scsi_normalize_sense(sense_buf, SCSI_SENSE_BUFFERSIZE,
+ &sshdr);
+ switch (sshdr.sense_key) {
+ case NO_SENSE:
+ case RECOVERED_ERROR:
+ /* fall through */
+ case NOT_READY:
+ result &= ~SAM_STAT_CHECK_CONDITION;
+ break;
+ case UNIT_ATTENTION:
+ switch (sshdr.asc) {
+ case 0x29: /* Power on Reset or Device Reset */
+ /* fall through */
+ case 0x2A: /* Device capacity changed */
+ case 0x3F: /* Report LUNs changed */
+ /* Retry the command once more */
+ if (retry_cnt++ < 1) {
+ kfree(cmd_buf);
+ kfree(scsi_cmd);
+ kfree(sense_buf);
+ goto retry;
+ }
+ }
+ break;
+ default:
+ break;
+ }
+ }
+ }
+
+ if (result) {
+ dev_err(dev, "%s: command failed, result=0x%x\n",
+ __func__, result);
+ rc = -EIO;
+ goto out;
+ }
+
+ /*
+ * Read cap was successful, grab values from the buffer;
+ * note that we don't need to worry about unaligned access
+ * as the buffer is allocated on an aligned boundary.
+ */
+ mutex_lock(&gli->mutex);
+ gli->max_lba = be64_to_cpu(*((u64 *)&cmd_buf[0]));
+ gli->blk_len = be32_to_cpu(*((u32 *)&cmd_buf[8]));
+ mutex_unlock(&gli->mutex);
+
+out:
+ kfree(cmd_buf);
+ kfree(scsi_cmd);
+ kfree(sense_buf);
+
+ dev_dbg(dev, "%s: maxlba=%lld blklen=%d rc=%d\n",
+ __func__, gli->max_lba, gli->blk_len, rc);
+ return rc;
+}
+
+/**
+ * get_rhte() - obtains validated resource handle table entry reference
+ * @ctxi: Context owning the resource handle.
+ * @rhndl: Resource handle associated with entry.
+ * @lli: LUN associated with request.
+ *
+ * Return: Validated RHTE on success, NULL on failure
+ */
+struct sisl_rht_entry *get_rhte(struct ctx_info *ctxi, res_hndl_t rhndl,
+ struct llun_info *lli)
+{
+ struct sisl_rht_entry *rhte = NULL;
+
+ if (unlikely(!ctxi->rht_start)) {
+ pr_debug("%s: Context does not have allocated RHT!\n",
+ __func__);
+ goto out;
+ }
+
+ if (unlikely(rhndl >= MAX_RHT_PER_CONTEXT)) {
+ pr_debug("%s: Bad resource handle! (%d)\n", __func__, rhndl);
+ goto out;
+ }
+
+ if (unlikely(ctxi->rht_lun[rhndl] != lli)) {
+ pr_debug("%s: Bad resource handle LUN! (%d)\n",
+ __func__, rhndl);
+ goto out;
+ }
+
+ rhte = &ctxi->rht_start[rhndl];
+ if (unlikely(rhte->nmask == 0)) {
+ pr_debug("%s: Unopened resource handle! (%d)\n",
+ __func__, rhndl);
+ rhte = NULL;
+ goto out;
+ }
+
+out:
+ return rhte;
+}
+
+/**
+ * rhte_checkout() - obtains free/empty resource handle table entry
+ * @ctxi: Context owning the resource handle.
+ * @lli: LUN associated with request.
+ *
+ * Return: Free RHTE on success, NULL on failure
+ */
+struct sisl_rht_entry *rhte_checkout(struct ctx_info *ctxi,
+ struct llun_info *lli)
+{
+ struct sisl_rht_entry *rhte = NULL;
+ int i;
+
+ /* Find a free RHT entry */
+ for (i = 0; i < MAX_RHT_PER_CONTEXT; i++)
+ if (ctxi->rht_start[i].nmask == 0) {
+ rhte = &ctxi->rht_start[i];
+ ctxi->rht_out++;
+ break;
+ }
+
+ if (likely(rhte))
+ ctxi->rht_lun[i] = lli;
+
+ pr_debug("%s: returning rhte=%p (%d)\n", __func__, rhte, i);
+ return rhte;
+}
+
+/**
+ * rhte_checkin() - releases a resource handle table entry
+ * @ctxi: Context owning the resource handle.
+ * @rhte: RHTE to release.
+ */
+void rhte_checkin(struct ctx_info *ctxi,
+ struct sisl_rht_entry *rhte)
+{
+ u32 rsrc_handle = rhte - ctxi->rht_start;
+
+ rhte->nmask = 0;
+ rhte->fp = 0;
+ ctxi->rht_out--;
+ ctxi->rht_lun[rsrc_handle] = NULL;
+}
+
+/**
+ * rhte_format1() - populates a RHTE for format 1
+ * @rhte: RHTE to populate.
+ * @lun_id: LUN ID of LUN associated with RHTE.
+ * @perm: Desired permissions for RHTE.
+ * @port_sel: Port selection mask
+ */
+static void rht_format1(struct sisl_rht_entry *rhte, u64 lun_id, u32 perm,
+ u32 port_sel)
+{
+ /*
+ * Populate the Format 1 RHT entry for direct access (physical
+ * LUN) using the synchronization sequence defined in the
+ * SISLite specification.
+ */
+ struct sisl_rht_entry_f1 dummy = { 0 };
+ struct sisl_rht_entry_f1 *rhte_f1 = (struct sisl_rht_entry_f1 *)rhte;
+
+ memset(rhte_f1, 0, sizeof(*rhte_f1));
+ rhte_f1->fp = SISL_RHT_FP(1U, 0);
+ dma_wmb(); /* Make setting of format bit visible */
+
+ rhte_f1->lun_id = lun_id;
+ dma_wmb(); /* Make setting of LUN id visible */
+
+ /*
+ * Use a dummy RHT Format 1 entry to build the second dword
+ * of the entry that must be populated in a single write when
+ * enabled (valid bit set to TRUE).
+ */
+ dummy.valid = 0x80;
+ dummy.fp = SISL_RHT_FP(1U, perm);
+ dummy.port_sel = port_sel;
+ rhte_f1->dw = dummy.dw;
+
+ dma_wmb(); /* Make remaining RHT entry fields visible */
+}
+
+/**
+ * cxlflash_lun_attach() - attaches a user to a LUN and manages the LUN's mode
+ * @gli: LUN to attach.
+ * @mode: Desired mode of the LUN.
+ * @locked: Mutex status on current thread.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+int cxlflash_lun_attach(struct glun_info *gli, enum lun_mode mode, bool locked)
+{
+ int rc = 0;
+
+ if (!locked)
+ mutex_lock(&gli->mutex);
+
+ if (gli->mode == MODE_NONE)
+ gli->mode = mode;
+ else if (gli->mode != mode) {
+ pr_debug("%s: LUN operating in mode %d, requested mode %d\n",
+ __func__, gli->mode, mode);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ gli->users++;
+ WARN_ON(gli->users <= 0);
+out:
+ pr_debug("%s: Returning rc=%d gli->mode=%u gli->users=%u\n",
+ __func__, rc, gli->mode, gli->users);
+ if (!locked)
+ mutex_unlock(&gli->mutex);
+ return rc;
+}
+
+/**
+ * cxlflash_lun_detach() - detaches a user from a LUN and resets the LUN's mode
+ * @gli: LUN to detach.
+ */
+void cxlflash_lun_detach(struct glun_info *gli)
+{
+ mutex_lock(&gli->mutex);
+ WARN_ON(gli->mode == MODE_NONE);
+ if (--gli->users == 0)
+ gli->mode = MODE_NONE;
+ pr_debug("%s: gli->users=%u\n", __func__, gli->users);
+ WARN_ON(gli->users < 0);
+ mutex_unlock(&gli->mutex);
+}
+
+/**
+ * _cxlflash_disk_release() - releases the specified resource entry
+ * @sdev: SCSI device associated with LUN.
+ * @ctxi: Context owning resources.
+ * @release: Release ioctl data structure.
+ *
+ * Note that the AFU sync should _not_ be performed when the context is sitting
+ * on the error recovery list. A context on the error recovery list is not known
+ * to the AFU due to reset. When the context is recovered, it will be reattached
+ * and made known again to the AFU.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+int _cxlflash_disk_release(struct scsi_device *sdev,
+ struct ctx_info *ctxi,
+ struct dk_cxlflash_release *release)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+ struct afu *afu = cfg->afu;
+ bool put_ctx = false;
+
+ res_hndl_t rhndl = release->rsrc_handle;
+
+ int rc = 0;
+ u64 ctxid = DECODE_CTXID(release->context_id),
+ rctxid = release->context_id;
+
+ struct sisl_rht_entry *rhte;
+ struct sisl_rht_entry_f1 *rhte_f1;
+
+ dev_dbg(dev, "%s: ctxid=%llu rhndl=0x%llx gli->mode=%u gli->users=%u\n",
+ __func__, ctxid, release->rsrc_handle, gli->mode, gli->users);
+
+ if (!ctxi) {
+ ctxi = get_context(cfg, rctxid, lli, CTX_CTRL_ERR_FALLBACK);
+ if (unlikely(!ctxi)) {
+ dev_dbg(dev, "%s: Bad context! (%llu)\n",
+ __func__, ctxid);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ put_ctx = true;
+ }
+
+ rhte = get_rhte(ctxi, rhndl, lli);
+ if (unlikely(!rhte)) {
+ dev_dbg(dev, "%s: Bad resource handle! (%d)\n",
+ __func__, rhndl);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ switch (gli->mode) {
+ case MODE_PHYSICAL:
+ /*
+ * Clear the Format 1 RHT entry for direct access
+ * (physical LUN) using the synchronization sequence
+ * defined in the SISLite specification.
+ */
+ rhte_f1 = (struct sisl_rht_entry_f1 *)rhte;
+
+ rhte_f1->valid = 0;
+ dma_wmb(); /* Make revocation of RHT entry visible */
+
+ rhte_f1->lun_id = 0;
+ dma_wmb(); /* Make clearing of LUN id visible */
+
+ rhte_f1->dw = 0;
+ dma_wmb(); /* Make RHT entry bottom-half clearing visible */
+
+ if (!ctxi->err_recovery_active)
+ cxlflash_afu_sync(afu, ctxid, rhndl, AFU_HW_SYNC);
+ break;
+ default:
+ WARN(1, "Unsupported LUN mode!");
+ goto out;
+ }
+
+ rhte_checkin(ctxi, rhte);
+ cxlflash_lun_detach(gli);
+
+out:
+ if (put_ctx)
+ put_context(ctxi);
+ dev_dbg(dev, "%s: returning rc=%d\n", __func__, rc);
+ return rc;
+}
+
+int cxlflash_disk_release(struct scsi_device *sdev,
+ struct dk_cxlflash_release *release)
+{
+ return _cxlflash_disk_release(sdev, NULL, release);
+}
+
+/**
+ * destroy_context() - releases a context
+ * @cfg: Internal structure associated with the host.
+ * @ctxi: Context to release.
+ *
+ * Note that the rht_lun member of the context was cut from a single
+ * allocation when the context was created and therefore does not need
+ * to be explicitly freed. Also note that we conditionally check for the
+ * existence of the context control map before clearing the RHT registers
+ * and context capabilities because it is possible to destroy a context
+ * while the context is in the error state (previous mapping was removed
+ * [so we don't have to worry about clearing] and context is waiting for
+ * a new mapping).
+ */
+static void destroy_context(struct cxlflash_cfg *cfg,
+ struct ctx_info *ctxi)
+{
+ struct afu *afu = cfg->afu;
+
+ WARN_ON(!list_empty(&ctxi->luns));
+
+ /* Clear RHT registers and drop all capabilities for this context */
+ if (afu->afu_map && ctxi->ctrl_map) {
+ writeq_be(0, &ctxi->ctrl_map->rht_start);
+ writeq_be(0, &ctxi->ctrl_map->rht_cnt_id);
+ writeq_be(0, &ctxi->ctrl_map->ctx_cap);
+ }
+
+ /* Free memory associated with context */
+ free_page((ulong)ctxi->rht_start);
+ kfree(ctxi->rht_lun);
+ kfree(ctxi);
+ atomic_dec_if_positive(&cfg->num_user_contexts);
+}
+
+/**
+ * create_context() - allocates and initializes a context
+ * @cfg: Internal structure associated with the host.
+ * @ctx: Previously obtained CXL context reference.
+ * @ctxid: Previously obtained process element associated with CXL context.
+ * @adap_fd: Previously obtained adapter fd associated with CXL context.
+ * @file: Previously obtained file associated with CXL context.
+ * @perms: User-specified permissions.
+ *
+ * The context's mutex is locked when an allocated context is returned.
+ *
+ * Return: Allocated context on success, NULL on failure
+ */
+static struct ctx_info *create_context(struct cxlflash_cfg *cfg,
+ struct cxl_context *ctx, int ctxid,
+ int adap_fd, struct file *file,
+ u32 perms)
+{
+ struct device *dev = &cfg->dev->dev;
+ struct afu *afu = cfg->afu;
+ struct ctx_info *ctxi = NULL;
+ struct llun_info **lli = NULL;
+ struct sisl_rht_entry *rhte;
+
+ ctxi = kzalloc(sizeof(*ctxi), GFP_KERNEL);
+ lli = kzalloc((MAX_RHT_PER_CONTEXT * sizeof(*lli)), GFP_KERNEL);
+ if (unlikely(!ctxi || !lli)) {
+ dev_err(dev, "%s: Unable to allocate context!\n", __func__);
+ goto err;
+ }
+
+ rhte = (struct sisl_rht_entry *)get_zeroed_page(GFP_KERNEL);
+ if (unlikely(!rhte)) {
+ dev_err(dev, "%s: Unable to allocate RHT!\n", __func__);
+ goto err;
+ }
+
+ ctxi->rht_lun = lli;
+ ctxi->rht_start = rhte;
+ ctxi->rht_perms = perms;
+
+ ctxi->ctrl_map = &afu->afu_map->ctrls[ctxid].ctrl;
+ ctxi->ctxid = ENCODE_CTXID(ctxi, ctxid);
+ ctxi->lfd = adap_fd;
+ ctxi->pid = current->tgid; /* tgid = pid */
+ ctxi->ctx = ctx;
+ ctxi->file = file;
+ mutex_init(&ctxi->mutex);
+ INIT_LIST_HEAD(&ctxi->luns);
+ INIT_LIST_HEAD(&ctxi->list); /* initialize for list_empty() */
+
+ atomic_inc(&cfg->num_user_contexts);
+ mutex_lock(&ctxi->mutex);
+out:
+ return ctxi;
+
+err:
+ kfree(lli);
+ kfree(ctxi);
+ ctxi = NULL;
+ goto out;
+}
+
+/**
+ * _cxlflash_disk_detach() - detaches a LUN from a context
+ * @sdev: SCSI device associated with LUN.
+ * @ctxi: Context owning resources.
+ * @detach: Detach ioctl data structure.
+ *
+ * As part of the detach, all per-context resources associated with the LUN
+ * are cleaned up. When detaching the last LUN for a context, the context
+ * itself is cleaned up and released.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int _cxlflash_disk_detach(struct scsi_device *sdev,
+ struct ctx_info *ctxi,
+ struct dk_cxlflash_detach *detach)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+ struct llun_info *lli = sdev->hostdata;
+ struct lun_access *lun_access, *t;
+ struct dk_cxlflash_release rel;
+ bool put_ctx = false;
+
+ int i;
+ int rc = 0;
+ int lfd;
+ u64 ctxid = DECODE_CTXID(detach->context_id),
+ rctxid = detach->context_id;
+
+ dev_dbg(dev, "%s: ctxid=%llu\n", __func__, ctxid);
+
+ if (!ctxi) {
+ ctxi = get_context(cfg, rctxid, lli, CTX_CTRL_ERR_FALLBACK);
+ if (unlikely(!ctxi)) {
+ dev_dbg(dev, "%s: Bad context! (%llu)\n",
+ __func__, ctxid);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ put_ctx = true;
+ }
+
+ /* Cleanup outstanding resources tied to this LUN */
+ if (ctxi->rht_out) {
+ marshal_det_to_rele(detach, &rel);
+ for (i = 0; i < MAX_RHT_PER_CONTEXT; i++) {
+ if (ctxi->rht_lun[i] == lli) {
+ rel.rsrc_handle = i;
+ _cxlflash_disk_release(sdev, ctxi, &rel);
+ }
+
+ /* No need to loop further if we're done */
+ if (ctxi->rht_out == 0)
+ break;
+ }
+ }
+
+ /* Take our LUN out of context, free the node */
+ list_for_each_entry_safe(lun_access, t, &ctxi->luns, list)
+ if (lun_access->lli == lli) {
+ list_del(&lun_access->list);
+ kfree(lun_access);
+ lun_access = NULL;
+ break;
+ }
+
+ /* Tear down context following last LUN cleanup */
+ if (list_empty(&ctxi->luns)) {
+ ctxi->unavail = true;
+ mutex_unlock(&ctxi->mutex);
+ mutex_lock(&cfg->ctx_tbl_list_mutex);
+ mutex_lock(&ctxi->mutex);
+
+ /* Might not have been in error list so conditionally remove */
+ if (!list_empty(&ctxi->list))
+ list_del(&ctxi->list);
+ cfg->ctx_tbl[ctxid] = NULL;
+ mutex_unlock(&cfg->ctx_tbl_list_mutex);
+ mutex_unlock(&ctxi->mutex);
+
+ lfd = ctxi->lfd;
+ destroy_context(cfg, ctxi);
+ ctxi = NULL;
+ put_ctx = false;
+
+ /*
+ * As a last step, clean up external resources when not
+ * already on an external cleanup thread, i.e.: close(adap_fd).
+ *
+ * NOTE: this will free up the context from the CXL services,
+ * allowing it to dole out the same context_id on a future
+ * (or even currently in-flight) disk_attach operation.
+ */
+ if (lfd != -1)
+ sys_close(lfd);
+ }
+
+out:
+ if (put_ctx)
+ put_context(ctxi);
+ dev_dbg(dev, "%s: returning rc=%d\n", __func__, rc);
+ return rc;
+}
+
+static int cxlflash_disk_detach(struct scsi_device *sdev,
+ struct dk_cxlflash_detach *detach)
+{
+ return _cxlflash_disk_detach(sdev, NULL, detach);
+}
+
+/**
+ * cxlflash_cxl_release() - release handler for adapter file descriptor
+ * @inode: File-system inode associated with fd.
+ * @file: File installed with adapter file descriptor.
+ *
+ * This routine is the release handler for the fops registered with
+ * the CXL services on an initial attach for a context. It is called
+ * when a close is performed on the adapter file descriptor returned
+ * to the user. Programmatically, the user is not required to perform
+ * the close, as it is handled internally via the detach ioctl when
+ * a context is being removed. Note that nothing prevents the user
+ * from performing a close, but the user should be aware that doing
+ * so is considered catastrophic and subsequent usage of the superpipe
+ * API with previously saved off tokens will fail.
+ *
+ * When initiated from an external close (either by the user or via
+ * a process tear down), the routine derives the context reference
+ * and calls detach for each LUN associated with the context. The
+ * final detach operation will cause the context itself to be freed.
+ * Note that the saved off lfd is reset prior to calling detach to
+ * signify that the final detach should not perform a close.
+ *
+ * When initiated from a detach operation as part of the tear down
+ * of a context, the context is first completely freed and then the
+ * close is performed. This routine will fail to derive the context
+ * reference (due to the context having already been freed) and then
+ * call into the CXL release entry point.
+ *
+ * Thus, with exception to when the CXL process element (context id)
+ * lookup fails (a case that should theoretically never occur), every
+ * call into this routine results in a complete freeing of a context.
+ *
+ * As part of the detach, all per-context resources associated with the LUN
+ * are cleaned up. When detaching the last LUN for a context, the context
+ * itself is cleaned up and released.
+ *
+ * Return: 0 on success
+ */
+static int cxlflash_cxl_release(struct inode *inode, struct file *file)
+{
+ struct cxl_context *ctx = cxl_fops_get_context(file);
+ struct cxlflash_cfg *cfg = container_of(file->f_op, struct cxlflash_cfg,
+ cxl_fops);
+ struct device *dev = &cfg->dev->dev;
+ struct ctx_info *ctxi = NULL;
+ struct dk_cxlflash_detach detach = { { 0 }, 0 };
+ struct lun_access *lun_access, *t;
+ enum ctx_ctrl ctrl = CTX_CTRL_ERR_FALLBACK | CTX_CTRL_FILE;
+ int ctxid;
+
+ ctxid = cxl_process_element(ctx);
+ if (unlikely(ctxid < 0)) {
+ dev_err(dev, "%s: Context %p was closed! (%d)\n",
+ __func__, ctx, ctxid);
+ goto out;
+ }
+
+ ctxi = get_context(cfg, ctxid, file, ctrl);
+ if (unlikely(!ctxi)) {
+ ctxi = get_context(cfg, ctxid, file, ctrl | CTX_CTRL_CLONE);
+ if (!ctxi) {
+ dev_dbg(dev, "%s: Context %d already free!\n",
+ __func__, ctxid);
+ goto out_release;
+ }
+
+ dev_dbg(dev, "%s: Another process owns context %d!\n",
+ __func__, ctxid);
+ put_context(ctxi);
+ goto out;
+ }
+
+ dev_dbg(dev, "%s: close(%d) for context %d\n",
+ __func__, ctxi->lfd, ctxid);
+
+ /* Reset the file descriptor to indicate we're on a close() thread */
+ ctxi->lfd = -1;
+ detach.context_id = ctxi->ctxid;
+ list_for_each_entry_safe(lun_access, t, &ctxi->luns, list)
+ _cxlflash_disk_detach(lun_access->sdev, ctxi, &detach);
+out_release:
+ cxl_fd_release(inode, file);
+out:
+ dev_dbg(dev, "%s: returning\n", __func__);
+ return 0;
+}
+
+/**
+ * unmap_context() - clears a previously established mapping
+ * @ctxi: Context owning the mapping.
+ *
+ * This routine is used to switch between the error notification page
+ * (dummy page of all 1's) and the real mapping (established by the CXL
+ * fault handler).
+ */
+static void unmap_context(struct ctx_info *ctxi)
+{
+ unmap_mapping_range(ctxi->file->f_mapping, 0, 0, 1);
+}
+
+/**
+ * get_err_page() - obtains and allocates the error notification page
+ *
+ * Return: error notification page on success, NULL on failure
+ */
+static struct page *get_err_page(void)
+{
+ struct page *err_page = global.err_page;
+
+ if (unlikely(!err_page)) {
+ err_page = alloc_page(GFP_KERNEL);
+ if (unlikely(!err_page)) {
+ pr_err("%s: Unable to allocate err_page!\n", __func__);
+ goto out;
+ }
+
+ memset(page_address(err_page), -1, PAGE_SIZE);
+
+ /* Serialize update w/ other threads to avoid a leak */
+ mutex_lock(&global.mutex);
+ if (likely(!global.err_page))
+ global.err_page = err_page;
+ else {
+ __free_page(err_page);
+ err_page = global.err_page;
+ }
+ mutex_unlock(&global.mutex);
+ }
+
+out:
+ pr_debug("%s: returning err_page=%p\n", __func__, err_page);
+ return err_page;
+}
+
+/**
+ * cxlflash_mmap_fault() - mmap fault handler for adapter file descriptor
+ * @vma: VM area associated with mapping.
+ * @vmf: VM fault associated with current fault.
+ *
+ * To support error notification via MMIO, faults are 'caught' by this routine
+ * that was inserted before passing back the adapter file descriptor on attach.
+ * When a fault occurs, this routine evaluates if error recovery is active and
+ * if so, installs the error page to 'notify' the user about the error state.
+ * During normal operation, the fault is simply handled by the original fault
+ * handler that was installed by CXL services as part of initializing the
+ * adapter file descriptor. The VMA's page protection bits are toggled to
+ * indicate cached/not-cached depending on the memory backing the fault.
+ *
+ * Return: 0 on success, VM_FAULT_SIGBUS on failure
+ */
+static int cxlflash_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct file *file = vma->vm_file;
+ struct cxl_context *ctx = cxl_fops_get_context(file);
+ struct cxlflash_cfg *cfg = container_of(file->f_op, struct cxlflash_cfg,
+ cxl_fops);
+ struct device *dev = &cfg->dev->dev;
+ struct ctx_info *ctxi = NULL;
+ struct page *err_page = NULL;
+ enum ctx_ctrl ctrl = CTX_CTRL_ERR_FALLBACK | CTX_CTRL_FILE;
+ int rc = 0;
+ int ctxid;
+
+ ctxid = cxl_process_element(ctx);
+ if (unlikely(ctxid < 0)) {
+ dev_err(dev, "%s: Context %p was closed! (%d)\n",
+ __func__, ctx, ctxid);
+ goto err;
+ }
+
+ ctxi = get_context(cfg, ctxid, file, ctrl);
+ if (unlikely(!ctxi)) {
+ dev_dbg(dev, "%s: Bad context! (%d)\n", __func__, ctxid);
+ goto err;
+ }
+
+ dev_dbg(dev, "%s: fault(%d) for context %d\n",
+ __func__, ctxi->lfd, ctxid);
+
+ if (likely(!ctxi->err_recovery_active)) {
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+ rc = ctxi->cxl_mmap_vmops->fault(vma, vmf);
+ } else {
+ dev_dbg(dev, "%s: err recovery active, use err_page!\n",
+ __func__);
+
+ err_page = get_err_page();
+ if (unlikely(!err_page)) {
+ dev_err(dev, "%s: Could not obtain error page!\n",
+ __func__);
+ rc = VM_FAULT_RETRY;
+ goto out;
+ }
+
+ get_page(err_page);
+ vmf->page = err_page;
+ vma->vm_page_prot = pgprot_cached(vma->vm_page_prot);
+ }
+
+out:
+ if (likely(ctxi))
+ put_context(ctxi);
+ dev_dbg(dev, "%s: returning rc=%d\n", __func__, rc);
+ return rc;
+
+err:
+ rc = VM_FAULT_SIGBUS;
+ goto out;
+}
+
+/*
+ * Local MMAP vmops to 'catch' faults
+ */
+static const struct vm_operations_struct cxlflash_mmap_vmops = {
+ .fault = cxlflash_mmap_fault,
+};
+
+/**
+ * cxlflash_cxl_mmap() - mmap handler for adapter file descriptor
+ * @file: File installed with adapter file descriptor.
+ * @vma: VM area associated with mapping.
+ *
+ * Installs local mmap vmops to 'catch' faults for error notification support.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int cxlflash_cxl_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct cxl_context *ctx = cxl_fops_get_context(file);
+ struct cxlflash_cfg *cfg = container_of(file->f_op, struct cxlflash_cfg,
+ cxl_fops);
+ struct device *dev = &cfg->dev->dev;
+ struct ctx_info *ctxi = NULL;
+ enum ctx_ctrl ctrl = CTX_CTRL_ERR_FALLBACK | CTX_CTRL_FILE;
+ int ctxid;
+ int rc = 0;
+
+ ctxid = cxl_process_element(ctx);
+ if (unlikely(ctxid < 0)) {
+ dev_err(dev, "%s: Context %p was closed! (%d)\n",
+ __func__, ctx, ctxid);
+ rc = -EIO;
+ goto out;
+ }
+
+ ctxi = get_context(cfg, ctxid, file, ctrl);
+ if (unlikely(!ctxi)) {
+ dev_dbg(dev, "%s: Bad context! (%d)\n", __func__, ctxid);
+ rc = -EIO;
+ goto out;
+ }
+
+ dev_dbg(dev, "%s: mmap(%d) for context %d\n",
+ __func__, ctxi->lfd, ctxid);
+
+ rc = cxl_fd_mmap(file, vma);
+ if (likely(!rc)) {
+ /* Insert ourself in the mmap fault handler path */
+ ctxi->cxl_mmap_vmops = vma->vm_ops;
+ vma->vm_ops = &cxlflash_mmap_vmops;
+ }
+
+out:
+ if (likely(ctxi))
+ put_context(ctxi);
+ return rc;
+}
+
+/*
+ * Local fops for adapter file descriptor
+ */
+static const struct file_operations cxlflash_cxl_fops = {
+ .owner = THIS_MODULE,
+ .mmap = cxlflash_cxl_mmap,
+ .release = cxlflash_cxl_release,
+};
+
+/**
+ * cxlflash_mark_contexts_error() - move contexts to error state and list
+ * @cfg: Internal structure associated with the host.
+ *
+ * A context is only moved over to the error list when there are no outstanding
+ * references to it. This ensures that a running operation has completed.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+int cxlflash_mark_contexts_error(struct cxlflash_cfg *cfg)
+{
+ int i, rc = 0;
+ struct ctx_info *ctxi = NULL;
+
+ mutex_lock(&cfg->ctx_tbl_list_mutex);
+
+ for (i = 0; i < MAX_CONTEXT; i++) {
+ ctxi = cfg->ctx_tbl[i];
+ if (ctxi) {
+ mutex_lock(&ctxi->mutex);
+ cfg->ctx_tbl[i] = NULL;
+ list_add(&ctxi->list, &cfg->ctx_err_recovery);
+ ctxi->err_recovery_active = true;
+ ctxi->ctrl_map = NULL;
+ unmap_context(ctxi);
+ mutex_unlock(&ctxi->mutex);
+ }
+ }
+
+ mutex_unlock(&cfg->ctx_tbl_list_mutex);
+ return rc;
+}
+
+/*
+ * Dummy NULL fops
+ */
+static const struct file_operations null_fops = {
+ .owner = THIS_MODULE,
+};
+
+/**
+ * cxlflash_disk_attach() - attach a LUN to a context
+ * @sdev: SCSI device associated with LUN.
+ * @attach: Attach ioctl data structure.
+ *
+ * Creates a context and attaches LUN to it. A LUN can only be attached
+ * one time to a context (subsequent attaches for the same context/LUN pair
+ * are not supported). Additional LUNs can be attached to a context by
+ * specifying the 'reuse' flag defined in the cxlflash_ioctl.h header.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int cxlflash_disk_attach(struct scsi_device *sdev,
+ struct dk_cxlflash_attach *attach)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+ struct afu *afu = cfg->afu;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+ struct cxl_ioctl_start_work *work;
+ struct ctx_info *ctxi = NULL;
+ struct lun_access *lun_access = NULL;
+ int rc = 0;
+ u32 perms;
+ int ctxid = -1;
+ u64 rctxid = 0UL;
+ struct file *file;
+
+ struct cxl_context *ctx;
+
+ int fd = -1;
+
+ /* On first attach set fileops */
+ if (atomic_read(&cfg->num_user_contexts) == 0)
+ cfg->cxl_fops = cxlflash_cxl_fops;
+
+ if (attach->num_interrupts > 4) {
+ dev_dbg(dev, "%s: Cannot support this many interrupts %llu\n",
+ __func__, attach->num_interrupts);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if (gli->max_lba == 0) {
+ dev_dbg(dev, "%s: No capacity info for this LUN (%016llX)\n",
+ __func__, lli->lun_id[sdev->channel]);
+ rc = read_cap16(sdev, lli);
+ if (rc) {
+ dev_err(dev, "%s: Invalid device! (%d)\n",
+ __func__, rc);
+ rc = -ENODEV;
+ goto out;
+ }
+ dev_dbg(dev, "%s: LBA = %016llX\n", __func__, gli->max_lba);
+ dev_dbg(dev, "%s: BLK_LEN = %08X\n", __func__, gli->blk_len);
+ }
+
+ if (attach->hdr.flags & DK_CXLFLASH_ATTACH_REUSE_CONTEXT) {
+ rctxid = attach->context_id;
+ ctxi = get_context(cfg, rctxid, NULL, 0);
+ if (!ctxi) {
+ dev_dbg(dev, "%s: Bad context! (%016llX)\n",
+ __func__, rctxid);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ list_for_each_entry(lun_access, &ctxi->luns, list)
+ if (lun_access->lli == lli) {
+ dev_dbg(dev, "%s: Already attached!\n",
+ __func__);
+ rc = -EINVAL;
+ goto out;
+ }
+ }
+
+ lun_access = kzalloc(sizeof(*lun_access), GFP_KERNEL);
+ if (unlikely(!lun_access)) {
+ dev_err(dev, "%s: Unable to allocate lun_access!\n", __func__);
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ lun_access->lli = lli;
+ lun_access->sdev = sdev;
+
+ /* Non-NULL context indicates reuse */
+ if (ctxi) {
+ dev_dbg(dev, "%s: Reusing context for LUN! (%016llX)\n",
+ __func__, rctxid);
+ list_add(&lun_access->list, &ctxi->luns);
+ fd = ctxi->lfd;
+ goto out_attach;
+ }
+
+ ctx = cxl_dev_context_init(cfg->dev);
+ if (unlikely(IS_ERR_OR_NULL(ctx))) {
+ dev_err(dev, "%s: Could not initialize context %p\n",
+ __func__, ctx);
+ rc = -ENODEV;
+ goto err0;
+ }
+
+ ctxid = cxl_process_element(ctx);
+ if (unlikely((ctxid > MAX_CONTEXT) || (ctxid < 0))) {
+ dev_err(dev, "%s: ctxid (%d) invalid!\n", __func__, ctxid);
+ rc = -EPERM;
+ goto err1;
+ }
+
+ file = cxl_get_fd(ctx, &cfg->cxl_fops, &fd);
+ if (unlikely(fd < 0)) {
+ rc = -ENODEV;
+ dev_err(dev, "%s: Could not get file descriptor\n", __func__);
+ goto err1;
+ }
+
+ /* Translate read/write O_* flags from fcntl.h to AFU permission bits */
+ perms = SISL_RHT_PERM(attach->hdr.flags + 1);
+
+ ctxi = create_context(cfg, ctx, ctxid, fd, file, perms);
+ if (unlikely(!ctxi)) {
+ dev_err(dev, "%s: Failed to create context! (%d)\n",
+ __func__, ctxid);
+ goto err2;
+ }
+
+ work = &ctxi->work;
+ work->num_interrupts = attach->num_interrupts;
+ work->flags = CXL_START_WORK_NUM_IRQS;
+
+ rc = cxl_start_work(ctx, work);
+ if (unlikely(rc)) {
+ dev_dbg(dev, "%s: Could not start context rc=%d\n",
+ __func__, rc);
+ goto err3;
+ }
+
+ rc = afu_attach(cfg, ctxi);
+ if (unlikely(rc)) {
+ dev_err(dev, "%s: Could not attach AFU rc %d\n", __func__, rc);
+ goto err4;
+ }
+
+ /*
+ * No error paths after this point. Once the fd is installed it's
+ * visible to user space and can't be undone safely on this thread.
+ * There is no need to worry about a deadlock here because no one
+ * knows about us yet; we can be the only one holding our mutex.
+ */
+ list_add(&lun_access->list, &ctxi->luns);
+ mutex_unlock(&ctxi->mutex);
+ mutex_lock(&cfg->ctx_tbl_list_mutex);
+ mutex_lock(&ctxi->mutex);
+ cfg->ctx_tbl[ctxid] = ctxi;
+ mutex_unlock(&cfg->ctx_tbl_list_mutex);
+ fd_install(fd, file);
+
+out_attach:
+ attach->hdr.return_flags = 0;
+ attach->context_id = ctxi->ctxid;
+ attach->block_size = gli->blk_len;
+ attach->mmio_size = sizeof(afu->afu_map->hosts[0].harea);
+ attach->last_lba = gli->max_lba;
+ attach->max_xfer = (sdev->host->max_sectors * 512) / gli->blk_len;
+
+out:
+ attach->adap_fd = fd;
+
+ if (ctxi)
+ put_context(ctxi);
+
+ dev_dbg(dev, "%s: returning ctxid=%d fd=%d bs=%lld rc=%d llba=%lld\n",
+ __func__, ctxid, fd, attach->block_size, rc, attach->last_lba);
+ return rc;
+
+err4:
+ cxl_stop_context(ctx);
+err3:
+ put_context(ctxi);
+ destroy_context(cfg, ctxi);
+ ctxi = NULL;
+err2:
+ /*
+ * Here, we're overriding the fops with a dummy all-NULL fops because
+ * fput() calls the release fop, which will cause us to mistakenly
+ * call into the CXL code. Rather than try to add yet more complexity
+ * to that routine (cxlflash_cxl_release) we should try to fix the
+ * issue here.
+ */
+ file->f_op = &null_fops;
+ fput(file);
+ put_unused_fd(fd);
+ fd = -1;
+err1:
+ cxl_release_context(ctx);
+err0:
+ kfree(lun_access);
+ goto out;
+}
+
+/**
+ * recover_context() - recovers a context in error
+ * @cfg: Internal structure associated with the host.
+ * @ctxi: Context to release.
+ *
+ * Restablishes the state for a context-in-error.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int recover_context(struct cxlflash_cfg *cfg, struct ctx_info *ctxi)
+{
+ struct device *dev = &cfg->dev->dev;
+ int rc = 0;
+ int old_fd, fd = -1;
+ int ctxid = -1;
+ struct file *file;
+ struct cxl_context *ctx;
+ struct afu *afu = cfg->afu;
+
+ ctx = cxl_dev_context_init(cfg->dev);
+ if (unlikely(IS_ERR_OR_NULL(ctx))) {
+ dev_err(dev, "%s: Could not initialize context %p\n",
+ __func__, ctx);
+ rc = -ENODEV;
+ goto out;
+ }
+
+ ctxid = cxl_process_element(ctx);
+ if (unlikely((ctxid > MAX_CONTEXT) || (ctxid < 0))) {
+ dev_err(dev, "%s: ctxid (%d) invalid!\n", __func__, ctxid);
+ rc = -EPERM;
+ goto err1;
+ }
+
+ file = cxl_get_fd(ctx, &cfg->cxl_fops, &fd);
+ if (unlikely(fd < 0)) {
+ rc = -ENODEV;
+ dev_err(dev, "%s: Could not get file descriptor\n", __func__);
+ goto err1;
+ }
+
+ rc = cxl_start_work(ctx, &ctxi->work);
+ if (unlikely(rc)) {
+ dev_dbg(dev, "%s: Could not start context rc=%d\n",
+ __func__, rc);
+ goto err2;
+ }
+
+ /* Update with new MMIO area based on updated context id */
+ ctxi->ctrl_map = &afu->afu_map->ctrls[ctxid].ctrl;
+
+ rc = afu_attach(cfg, ctxi);
+ if (rc) {
+ dev_err(dev, "%s: Could not attach AFU rc %d\n", __func__, rc);
+ goto err3;
+ }
+
+ /*
+ * No error paths after this point. Once the fd is installed it's
+ * visible to user space and can't be undone safely on this thread.
+ */
+ old_fd = ctxi->lfd;
+ ctxi->ctxid = ENCODE_CTXID(ctxi, ctxid);
+ ctxi->lfd = fd;
+ ctxi->ctx = ctx;
+ ctxi->file = file;
+
+ /*
+ * Put context back in table (note the reinit of the context list);
+ * we must first drop the context's mutex and then acquire it in
+ * order with the table/list mutex to avoid a deadlock - safe to do
+ * here because no one can find us at this moment in time.
+ */
+ mutex_unlock(&ctxi->mutex);
+ mutex_lock(&cfg->ctx_tbl_list_mutex);
+ mutex_lock(&ctxi->mutex);
+ list_del_init(&ctxi->list);
+ cfg->ctx_tbl[ctxid] = ctxi;
+ mutex_unlock(&cfg->ctx_tbl_list_mutex);
+ fd_install(fd, file);
+
+ /* Release the original adapter fd and associated CXL resources */
+ sys_close(old_fd);
+out:
+ dev_dbg(dev, "%s: returning ctxid=%d fd=%d rc=%d\n",
+ __func__, ctxid, fd, rc);
+ return rc;
+
+err3:
+ cxl_stop_context(ctx);
+err2:
+ fput(file);
+ put_unused_fd(fd);
+err1:
+ cxl_release_context(ctx);
+ goto out;
+}
+
+/**
+ * check_state() - checks and responds to the current adapter state
+ * @cfg: Internal structure associated with the host.
+ *
+ * This routine can block and should only be used on process context.
+ * Note that when waking up from waiting in limbo, the state is unknown
+ * and must be checked again before proceeding.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int check_state(struct cxlflash_cfg *cfg)
+{
+ struct device *dev = &cfg->dev->dev;
+ int rc = 0;
+
+retry:
+ switch (cfg->state) {
+ case STATE_LIMBO:
+ dev_dbg(dev, "%s: Limbo, going to wait...\n", __func__);
+ rc = wait_event_interruptible(cfg->limbo_waitq,
+ cfg->state != STATE_LIMBO);
+ if (unlikely(rc))
+ break;
+ goto retry;
+ case STATE_FAILTERM:
+ dev_dbg(dev, "%s: Failed/Terminating!\n", __func__);
+ rc = -ENODEV;
+ break;
+ default:
+ break;
+ }
+
+ return rc;
+}
+
+/**
+ * cxlflash_afu_recover() - initiates AFU recovery
+ * @sdev: SCSI device associated with LUN.
+ * @recover: Recover ioctl data structure.
+ *
+ * Only a single recovery is allowed at a time to avoid exhausting CXL
+ * resources (leading to recovery failure) in the event that we're up
+ * against the maximum number of contexts limit. For similar reasons,
+ * a context recovery is retried if there are multiple recoveries taking
+ * place at the same time and the failure was due to CXL services being
+ * unable to keep up.
+ *
+ * Because a user can detect an error condition before the kernel, it is
+ * quite possible for this routine to act as the kernel's EEH detection
+ * source (MMIO read of mbox_r). Because of this, there is a window of
+ * time where an EEH might have been detected but not yet 'serviced'
+ * (callback invoked, causing the device to enter limbo state). To avoid
+ * looping in this routine during that window, a 1 second sleep is in place
+ * between the time the MMIO failure is detected and the time a wait on the
+ * limbo wait queue is attempted via check_state().
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int cxlflash_afu_recover(struct scsi_device *sdev,
+ struct dk_cxlflash_recover_afu *recover)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+ struct llun_info *lli = sdev->hostdata;
+ struct afu *afu = cfg->afu;
+ struct ctx_info *ctxi = NULL;
+ struct mutex *mutex = &cfg->ctx_recovery_mutex;
+ u64 ctxid = DECODE_CTXID(recover->context_id),
+ rctxid = recover->context_id;
+ long reg;
+ int lretry = 20; /* up to 2 seconds */
+ int rc = 0;
+
+ atomic_inc(&cfg->recovery_threads);
+ rc = mutex_lock_interruptible(mutex);
+ if (rc)
+ goto out;
+
+ dev_dbg(dev, "%s: reason 0x%016llX rctxid=%016llX\n",
+ __func__, recover->reason, rctxid);
+
+retry:
+ /* Ensure that this process is attached to the context */
+ ctxi = get_context(cfg, rctxid, lli, CTX_CTRL_ERR_FALLBACK);
+ if (unlikely(!ctxi)) {
+ dev_dbg(dev, "%s: Bad context! (%llu)\n", __func__, ctxid);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if (ctxi->err_recovery_active) {
+retry_recover:
+ rc = recover_context(cfg, ctxi);
+ if (unlikely(rc)) {
+ dev_err(dev, "%s: Recovery failed for context %llu (rc=%d)\n",
+ __func__, ctxid, rc);
+ if ((rc == -ENODEV) &&
+ ((atomic_read(&cfg->recovery_threads) > 1) ||
+ (lretry--))) {
+ dev_dbg(dev, "%s: Going to try again!\n",
+ __func__);
+ mutex_unlock(mutex);
+ msleep(100);
+ rc = mutex_lock_interruptible(mutex);
+ if (rc)
+ goto out;
+ goto retry_recover;
+ }
+
+ goto out;
+ }
+
+ ctxi->err_recovery_active = false;
+ recover->context_id = ctxi->ctxid;
+ recover->adap_fd = ctxi->lfd;
+ recover->mmio_size = sizeof(afu->afu_map->hosts[0].harea);
+ recover->hdr.return_flags |=
+ DK_CXLFLASH_RECOVER_AFU_CONTEXT_RESET;
+ goto out;
+ }
+
+ /* Test if in error state */
+ reg = readq_be(&afu->ctrl_map->mbox_r);
+ if (reg == -1) {
+ dev_dbg(dev, "%s: MMIO read fail! Wait for recovery...\n",
+ __func__);
+ mutex_unlock(&ctxi->mutex);
+ ctxi = NULL;
+ ssleep(1);
+ rc = check_state(cfg);
+ if (unlikely(rc))
+ goto out;
+ goto retry;
+ }
+
+ dev_dbg(dev, "%s: MMIO working, no recovery required!\n", __func__);
+out:
+ if (likely(ctxi))
+ put_context(ctxi);
+ mutex_unlock(mutex);
+ atomic_dec_if_positive(&cfg->recovery_threads);
+ return rc;
+}
+
+/**
+ * process_sense() - evaluates and processes sense data
+ * @sdev: SCSI device associated with LUN.
+ * @verify: Verify ioctl data structure.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int process_sense(struct scsi_device *sdev,
+ struct dk_cxlflash_verify *verify)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+ u64 prev_lba = gli->max_lba;
+ struct scsi_sense_hdr sshdr = { 0 };
+ int rc = 0;
+
+ rc = scsi_normalize_sense((const u8 *)&verify->sense_data,
+ DK_CXLFLASH_VERIFY_SENSE_LEN, &sshdr);
+ if (!rc) {
+ dev_err(dev, "%s: Failed to normalize sense data!\n", __func__);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ switch (sshdr.sense_key) {
+ case NO_SENSE:
+ case RECOVERED_ERROR:
+ /* fall through */
+ case NOT_READY:
+ break;
+ case UNIT_ATTENTION:
+ switch (sshdr.asc) {
+ case 0x29: /* Power on Reset or Device Reset */
+ /* fall through */
+ case 0x2A: /* Device settings/capacity changed */
+ rc = read_cap16(sdev, lli);
+ if (rc) {
+ rc = -ENODEV;
+ break;
+ }
+ if (prev_lba != gli->max_lba)
+ dev_dbg(dev, "%s: Capacity changed old=%lld "
+ "new=%lld\n", __func__, prev_lba,
+ gli->max_lba);
+ break;
+ case 0x3F: /* Report LUNs changed, Rescan. */
+ scsi_scan_host(cfg->host);
+ break;
+ default:
+ rc = -EIO;
+ break;
+ }
+ break;
+ default:
+ rc = -EIO;
+ break;
+ }
+out:
+ dev_dbg(dev, "%s: sense_key %x asc %x ascq %x rc %d\n", __func__,
+ sshdr.sense_key, sshdr.asc, sshdr.ascq, rc);
+ return rc;
+}
+
+/**
+ * cxlflash_disk_verify() - verifies a LUN is the same and handle size changes
+ * @sdev: SCSI device associated with LUN.
+ * @verify: Verify ioctl data structure.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int cxlflash_disk_verify(struct scsi_device *sdev,
+ struct dk_cxlflash_verify *verify)
+{
+ int rc = 0;
+ struct ctx_info *ctxi = NULL;
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+ struct sisl_rht_entry *rhte = NULL;
+ res_hndl_t rhndl = verify->rsrc_handle;
+ u64 ctxid = DECODE_CTXID(verify->context_id),
+ rctxid = verify->context_id;
+ u64 last_lba = 0;
+
+ dev_dbg(dev, "%s: ctxid=%llu rhndl=%016llX, hint=%016llX, "
+ "flags=%016llX\n", __func__, ctxid, verify->rsrc_handle,
+ verify->hint, verify->hdr.flags);
+
+ ctxi = get_context(cfg, rctxid, lli, 0);
+ if (unlikely(!ctxi)) {
+ dev_dbg(dev, "%s: Bad context! (%llu)\n", __func__, ctxid);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ rhte = get_rhte(ctxi, rhndl, lli);
+ if (unlikely(!rhte)) {
+ dev_dbg(dev, "%s: Bad resource handle! (%d)\n",
+ __func__, rhndl);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /*
+ * Look at the hint/sense to see if it requires us to redrive
+ * inquiry (i.e. the Unit attention is due to the WWN changing).
+ */
+ if (verify->hint & DK_CXLFLASH_VERIFY_HINT_SENSE) {
+ rc = process_sense(sdev, verify);
+ if (unlikely(rc)) {
+ dev_err(dev, "%s: Failed to validate sense data (%d)\n",
+ __func__, rc);
+ goto out;
+ }
+ }
+
+ switch (gli->mode) {
+ case MODE_PHYSICAL:
+ last_lba = gli->max_lba;
+ break;
+ default:
+ WARN(1, "Unsupported LUN mode!");
+ }
+
+ verify->last_lba = last_lba;
+
+out:
+ if (likely(ctxi))
+ put_context(ctxi);
+ dev_dbg(dev, "%s: returning rc=%d llba=%llX\n",
+ __func__, rc, verify->last_lba);
+ return rc;
+}
+
+/**
+ * decode_ioctl() - translates an encoded ioctl to an easily identifiable string
+ * @cmd: The ioctl command to decode.
+ *
+ * Return: A string identifying the decoded ioctl.
+ */
+static char *decode_ioctl(int cmd)
+{
+ switch (cmd) {
+ case DK_CXLFLASH_ATTACH:
+ return __stringify_1(DK_CXLFLASH_ATTACH);
+ case DK_CXLFLASH_USER_DIRECT:
+ return __stringify_1(DK_CXLFLASH_USER_DIRECT);
+ case DK_CXLFLASH_RELEASE:
+ return __stringify_1(DK_CXLFLASH_RELEASE);
+ case DK_CXLFLASH_DETACH:
+ return __stringify_1(DK_CXLFLASH_DETACH);
+ case DK_CXLFLASH_VERIFY:
+ return __stringify_1(DK_CXLFLASH_VERIFY);
+ case DK_CXLFLASH_RECOVER_AFU:
+ return __stringify_1(DK_CXLFLASH_RECOVER_AFU);
+ case DK_CXLFLASH_MANAGE_LUN:
+ return __stringify_1(DK_CXLFLASH_MANAGE_LUN);
+ }
+
+ return "UNKNOWN";
+}
+
+/**
+ * cxlflash_disk_direct_open() - opens a direct (physical) disk
+ * @sdev: SCSI device associated with LUN.
+ * @arg: UDirect ioctl data structure.
+ *
+ * On successful return, the user is informed of the resource handle
+ * to be used to identify the direct lun and the size (in blocks) of
+ * the direct lun in last LBA format.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int cxlflash_disk_direct_open(struct scsi_device *sdev, void *arg)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+ struct afu *afu = cfg->afu;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+
+ struct dk_cxlflash_udirect *pphys = (struct dk_cxlflash_udirect *)arg;
+
+ u64 ctxid = DECODE_CTXID(pphys->context_id),
+ rctxid = pphys->context_id;
+ u64 lun_size = 0;
+ u64 last_lba = 0;
+ u64 rsrc_handle = -1;
+ u32 port = CHAN2PORT(sdev->channel);
+
+ int rc = 0;
+
+ struct ctx_info *ctxi = NULL;
+ struct sisl_rht_entry *rhte = NULL;
+
+ pr_debug("%s: ctxid=%llu ls=0x%llx\n", __func__, ctxid, lun_size);
+
+ rc = cxlflash_lun_attach(gli, MODE_PHYSICAL, false);
+ if (unlikely(rc)) {
+ dev_dbg(dev, "%s: Failed to attach to LUN! (PHYSICAL)\n",
+ __func__);
+ goto out;
+ }
+
+ ctxi = get_context(cfg, rctxid, lli, 0);
+ if (unlikely(!ctxi)) {
+ dev_dbg(dev, "%s: Bad context! (%llu)\n", __func__, ctxid);
+ rc = -EINVAL;
+ goto err1;
+ }
+
+ rhte = rhte_checkout(ctxi, lli);
+ if (unlikely(!rhte)) {
+ dev_dbg(dev, "%s: too many opens for this context\n", __func__);
+ rc = -EMFILE; /* too many opens */
+ goto err1;
+ }
+
+ rsrc_handle = (rhte - ctxi->rht_start);
+
+ rht_format1(rhte, lli->lun_id[sdev->channel], ctxi->rht_perms, port);
+ cxlflash_afu_sync(afu, ctxid, rsrc_handle, AFU_LW_SYNC);
+
+ last_lba = gli->max_lba;
+ pphys->hdr.return_flags = 0;
+ pphys->last_lba = last_lba;
+ pphys->rsrc_handle = rsrc_handle;
+
+out:
+ if (likely(ctxi))
+ put_context(ctxi);
+ dev_dbg(dev, "%s: returning handle 0x%llx rc=%d llba %lld\n",
+ __func__, rsrc_handle, rc, last_lba);
+ return rc;
+
+err1:
+ cxlflash_lun_detach(gli);
+ goto out;
+}
+
+/**
+ * ioctl_common() - common IOCTL handler for driver
+ * @sdev: SCSI device associated with LUN.
+ * @cmd: IOCTL command.
+ *
+ * Handles common fencing operations that are valid for multiple ioctls. Always
+ * allow through ioctls that are cleanup oriented in nature, even when operating
+ * in a failed/terminating state.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ioctl_common(struct scsi_device *sdev, int cmd)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+ struct llun_info *lli = sdev->hostdata;
+ int rc = 0;
+
+ if (unlikely(!lli)) {
+ dev_dbg(dev, "%s: Unknown LUN\n", __func__);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ rc = check_state(cfg);
+ if (unlikely(rc) && (cfg->state == STATE_FAILTERM)) {
+ switch (cmd) {
+ case DK_CXLFLASH_RELEASE:
+ case DK_CXLFLASH_DETACH:
+ dev_dbg(dev, "%s: Command override! (%d)\n",
+ __func__, rc);
+ rc = 0;
+ break;
+ }
+ }
+out:
+ return rc;
+}
+
+/**
+ * cxlflash_ioctl() - IOCTL handler for driver
+ * @sdev: SCSI device associated with LUN.
+ * @cmd: IOCTL command.
+ * @arg: Userspace ioctl data structure.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+int cxlflash_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
+{
+ typedef int (*sioctl) (struct scsi_device *, void *);
+
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+ struct afu *afu = cfg->afu;
+ struct dk_cxlflash_hdr *hdr;
+ char buf[sizeof(union cxlflash_ioctls)];
+ size_t size = 0;
+ bool known_ioctl = false;
+ int idx;
+ int rc = 0;
+ struct Scsi_Host *shost = sdev->host;
+ sioctl do_ioctl = NULL;
+
+ static const struct {
+ size_t size;
+ sioctl ioctl;
+ } ioctl_tbl[] = { /* NOTE: order matters here */
+ {sizeof(struct dk_cxlflash_attach), (sioctl)cxlflash_disk_attach},
+ {sizeof(struct dk_cxlflash_udirect), cxlflash_disk_direct_open},
+ {sizeof(struct dk_cxlflash_release), (sioctl)cxlflash_disk_release},
+ {sizeof(struct dk_cxlflash_detach), (sioctl)cxlflash_disk_detach},
+ {sizeof(struct dk_cxlflash_verify), (sioctl)cxlflash_disk_verify},
+ {sizeof(struct dk_cxlflash_recover_afu), (sioctl)cxlflash_afu_recover},
+ {sizeof(struct dk_cxlflash_manage_lun), (sioctl)cxlflash_manage_lun},
+ };
+
+ /* Restrict command set to physical support only for internal LUN */
+ if (afu->internal_lun)
+ switch (cmd) {
+ case DK_CXLFLASH_RELEASE:
+ dev_dbg(dev, "%s: %s not supported for lun_mode=%d\n",
+ __func__, decode_ioctl(cmd), afu->internal_lun);
+ rc = -EINVAL;
+ goto cxlflash_ioctl_exit;
+ }
+
+ switch (cmd) {
+ case DK_CXLFLASH_ATTACH:
+ case DK_CXLFLASH_USER_DIRECT:
+ case DK_CXLFLASH_RELEASE:
+ case DK_CXLFLASH_DETACH:
+ case DK_CXLFLASH_VERIFY:
+ case DK_CXLFLASH_RECOVER_AFU:
+ dev_dbg(dev, "%s: %s (%08X) on dev(%d/%d/%d/%llu)\n",
+ __func__, decode_ioctl(cmd), cmd, shost->host_no,
+ sdev->channel, sdev->id, sdev->lun);
+ rc = ioctl_common(sdev, cmd);
+ if (unlikely(rc))
+ goto cxlflash_ioctl_exit;
+
+ /* fall through */
+
+ case DK_CXLFLASH_MANAGE_LUN:
+ known_ioctl = true;
+ idx = _IOC_NR(cmd) - _IOC_NR(DK_CXLFLASH_ATTACH);
+ size = ioctl_tbl[idx].size;
+ do_ioctl = ioctl_tbl[idx].ioctl;
+
+ if (likely(do_ioctl))
+ break;
+
+ /* fall through */
+ default:
+ rc = -EINVAL;
+ goto cxlflash_ioctl_exit;
+ }
+
+ if (unlikely(copy_from_user(&buf, arg, size))) {
+ dev_err(dev, "%s: copy_from_user() fail! "
+ "size=%lu cmd=%d (%s) arg=%p\n",
+ __func__, size, cmd, decode_ioctl(cmd), arg);
+ rc = -EFAULT;
+ goto cxlflash_ioctl_exit;
+ }
+
+ hdr = (struct dk_cxlflash_hdr *)&buf;
+ if (hdr->version != DK_CXLFLASH_VERSION_0) {
+ dev_dbg(dev, "%s: Version %u not supported for %s\n",
+ __func__, hdr->version, decode_ioctl(cmd));
+ rc = -EINVAL;
+ goto cxlflash_ioctl_exit;
+ }
+
+ if (hdr->rsvd[0] || hdr->rsvd[1] || hdr->rsvd[2] || hdr->return_flags) {
+ dev_dbg(dev, "%s: Reserved/rflags populated!\n", __func__);
+ rc = -EINVAL;
+ goto cxlflash_ioctl_exit;
+ }
+
+ rc = do_ioctl(sdev, (void *)&buf);
+ if (likely(!rc))
+ if (unlikely(copy_to_user(arg, &buf, size))) {
+ dev_err(dev, "%s: copy_to_user() fail! "
+ "size=%lu cmd=%d (%s) arg=%p\n",
+ __func__, size, cmd, decode_ioctl(cmd), arg);
+ rc = -EFAULT;
+ }
+
+ /* fall through to exit */
+
+cxlflash_ioctl_exit:
+ if (unlikely(rc && known_ioctl))
+ dev_err(dev, "%s: ioctl %s (%08X) on dev(%d/%d/%d/%llu) "
+ "returned rc %d\n", __func__,
+ decode_ioctl(cmd), cmd, shost->host_no,
+ sdev->channel, sdev->id, sdev->lun, rc);
+ else
+ dev_dbg(dev, "%s: ioctl %s (%08X) on dev(%d/%d/%d/%llu) "
+ "returned rc %d\n", __func__, decode_ioctl(cmd),
+ cmd, shost->host_no, sdev->channel, sdev->id,
+ sdev->lun, rc);
+ return rc;
+}
projects / users / hch / misc.git / commitdiff