@@ -163,7 +163,8 @@ DK_CXLFLASH_ATTACH
- These tokens are only valid for the process under which they
were created. The child of a forked process cannot continue
- to use the context id or file descriptor created by its parent.
+ to use the context id or file descriptor created by its parent
+ (see DK_CXLFLASH_VLUN_CLONE for further details).
- These tokens are only valid for the lifetime of the context and
the process under which they were created. Once either is
@@ -193,6 +194,45 @@ DK_CXLFLASH_USER_DIRECT
treated as a resource handle that is returned to the user. The user
is then able to use the handle to reference the LUN during I/O.
+DK_CXLFLASH_USER_VIRTUAL
+------------------------
+ This ioctl is responsible for transitioning the LUN to virtual mode
+ of access and configuring the AFU for virtual access from user space
+ on a per-context basis. Additionally, the block size and last logical
+ block address (LBA) are returned to the user.
+
+ As mentioned previously, when operating in user space access mode,
+ LUNs may be accessed in whole or in part. Only one mode is allowed
+ at a time and if one mode is active (outstanding references exist),
+ requests to use the LUN in a different mode are denied.
+
+ The AFU is configured for virtual access from user space by adding
+ an entry to the AFU's resource handle table. The index of the entry
+ is treated as a resource handle that is returned to the user. The
+ user is then able to use the handle to reference the LUN during I/O.
+
+ By default, the virtual LUN is created with a size of 0. The user
+ would need to use the DK_CXLFLASH_VLUN_RESIZE ioctl to adjust the grow
+ the virtual LUN to a desired size. To avoid having to perform this
+ resize for the initial creation of the virtual LUN, the user has the
+ option of specifying a size as part of the DK_CXLFLASH_USER_VIRTUAL
+ ioctl, such that when success is returned to the user, the
+ resource handle that is provided is already referencing provisioned
+ storage. This is reflected by the last LBA being a non-zero value.
+
+DK_CXLFLASH_VLUN_RESIZE
+-----------------------
+ This ioctl is responsible for resizing a previously created virtual
+ LUN and will fail if invoked upon a LUN that is not in virtual
+ mode. Upon success, an updated last LBA is returned to the user
+ indicating the new size of the virtual LUN associated with the
+ resource handle.
+
+ The partitioning of virtual LUNs is jointly mediated by the cxlflash
+ driver and the AFU. An allocation table is kept for each LUN that is
+ operating in the virtual mode and used to program a LUN translation
+ table that the AFU references when provided with a resource handle.
+
DK_CXLFLASH_RELEASE
-------------------
This ioctl is responsible for releasing a previously obtained
@@ -214,6 +254,27 @@ DK_CXLFLASH_DETACH
success, all "tokens" which had been provided to the user from the
DK_CXLFLASH_ATTACH onward are no longer valid.
+DK_CXLFLASH_VLUN_CLONE
+----------------------
+ This ioctl is responsible for cloning a previously created
+ context to a more recently created context. It exists solely to
+ support maintaining user space access to storage after a process
+ forks. Upon success, the child process (which invoked the ioctl)
+ will have access to the same LUNs via the same resource handle(s)
+ and fd2 as the parent, but under a different context.
+
+ Context sharing across processes is not supported with CXL and
+ therefore each fork must be met with establishing a new context
+ for the child process. This ioctl simplifies the state management
+ and playback required by a user in such a scenario. When a process
+ forks, child process can clone the parents context by first creating
+ a context (via DK_CXLFLASH_ATTACH) and then using this ioctl to
+ perform the clone from the parent to the child.
+
+ The clone itself is fairly simple. The resource handle and lun
+ translation tables are copied from the parent context to the child's
+ and then synced with the AFU.
+
DK_CXLFLASH_VERIFY
------------------
This ioctl is used to detect various changes such as the capacity of
@@ -1,2 +1,2 @@
obj-$(CONFIG_CXLFLASH) += cxlflash.o
-cxlflash-y += main.o superpipe.o lunmgt.o
+cxlflash-y += main.o superpipe.o lunmgt.o vlun.o
@@ -116,6 +116,9 @@ struct cxlflash_cfg {
atomic_t num_user_contexts;
+ /* Parameters that are LUN table related */
+ int last_lun_index[CXLFLASH_NUM_FC_PORTS];
+ int promote_lun_index;
struct list_head lluns; /* list of llun_info structs */
wait_queue_head_t tmf_waitq;
@@ -200,5 +203,6 @@ int cxlflash_ioctl(struct scsi_device *, int, void __user *);
void cxlflash_stop_term_user_contexts(struct cxlflash_cfg *);
int cxlflash_mark_contexts_error(struct cxlflash_cfg *);
void cxlflash_term_local_luns(struct cxlflash_cfg *);
+void cxlflash_restore_luntable(struct cxlflash_cfg *);
#endif /* ifndef _CXLFLASH_COMMON_H */
@@ -20,6 +20,7 @@
#include "sislite.h"
#include "common.h"
+#include "vlun.h"
#include "superpipe.h"
/**
@@ -42,6 +43,7 @@ static struct llun_info *create_local(struct scsi_device *sdev, u8 *wwid)
lli->sdev = sdev;
lli->newly_created = true;
lli->host_no = sdev->host->host_no;
+ lli->in_table = false;
memcpy(lli->wwid, wwid, DK_CXLFLASH_MANAGE_LUN_WWID_LEN);
out:
@@ -208,6 +210,7 @@ void cxlflash_term_global_luns(void)
mutex_lock(&global.mutex);
list_for_each_entry_safe(gli, temp, &global.gluns, list) {
list_del(&gli->list);
+ cxlflash_ba_terminate(&gli->blka.ba_lun);
kfree(gli);
}
mutex_unlock(&global.mutex);
@@ -1989,6 +1989,8 @@ static int init_afu(struct cxlflash_cfg *cfg)
afu_err_intr_init(cfg->afu);
atomic64_set(&afu->room, readq_be(&afu->host_map->cmd_room));
+ /* Restore the LUN mappings */
+ cxlflash_restore_luntable(cfg);
err1:
pr_debug("%s: returning rc=%d\n", __func__, rc);
return rc;
@@ -2286,6 +2288,17 @@ static int cxlflash_probe(struct pci_dev *pdev,
cfg->init_state = INIT_STATE_NONE;
cfg->dev = pdev;
+
+ /*
+ * The promoted LUNs move to the top of the LUN table. The rest stay
+ * on the bottom half. The bottom half grows from the end
+ * (index = 255), whereas the top half grows from the beginning
+ * (index = 0).
+ */
+ cfg->promote_lun_index = 0;
+ cfg->last_lun_index[0] = CXLFLASH_NUM_VLUNS/2 - 1;
+ cfg->last_lun_index[1] = CXLFLASH_NUM_VLUNS/2 - 1;
+
cfg->dev_id = (struct pci_device_id *)dev_id;
cfg->mcctx = NULL;
@@ -397,16 +397,17 @@ struct cxlflash_afu_map {
};
};
-/* LBA translation control blocks */
-
+/*
+ * LXT - LBA Translation Table
+ * LXT control blocks
+ */
struct sisl_lxt_entry {
u64 rlba_base; /* bits 0:47 is base
- * b48:55 is lun index
- * b58:59 is write & read perms
- * (if no perm, afu_rc=0x15)
- * b60:63 is port_sel mask
- */
-
+ * b48:55 is lun index
+ * b58:59 is write & read perms
+ * (if no perm, afu_rc=0x15)
+ * b60:63 is port_sel mask
+ */
};
/*
@@ -465,4 +466,7 @@ struct sisl_rht_entry_f1 {
#define TMF_LUN_RESET 0x1U
#define TMF_CLEAR_ACA 0x2U
+
+#define SISLITE_MAX_WS_BLOCKS 512
+
#endif /* _SISLITE_H */
@@ -26,11 +26,25 @@
#include "sislite.h"
#include "common.h"
+#include "vlun.h"
#include "superpipe.h"
struct cxlflash_global global;
/**
+ * marshal_rele_to_resize() - translate release to resize structure
+ * @rele: Source structure from which to translate/copy.
+ * @resize: Destination structure for the translate/copy.
+ */
+static void marshal_rele_to_resize(struct dk_cxlflash_release *release,
+ struct dk_cxlflash_resize *resize)
+{
+ resize->hdr = release->hdr;
+ resize->context_id = release->context_id;
+ resize->rsrc_handle = release->rsrc_handle;
+}
+
+/**
* marshal_det_to_rele() - translate detach to release structure
* @detach: Destination structure for the translate/copy.
* @rele: Source structure from which to translate/copy.
@@ -449,6 +463,7 @@ void rhte_checkin(struct ctx_info *ctxi,
rhte->fp = 0;
ctxi->rht_out--;
ctxi->rht_lun[rsrc_handle] = NULL;
+ ctxi->rht_needs_ws[rsrc_handle] = false;
}
/**
@@ -526,13 +541,21 @@ out:
/**
* cxlflash_lun_detach() - detaches a user from a LUN and resets the LUN's mode
* @gli: LUN to detach.
+ *
+ * When resetting the mode, terminate block allocation resources as they
+ * are no longer required (service is safe to call even when block allocation
+ * resources were not present - such as when transitioning from physical mode).
+ * These resources will be reallocated when needed (subsequent transition to
+ * virtual mode).
*/
void cxlflash_lun_detach(struct glun_info *gli)
{
mutex_lock(&gli->mutex);
WARN_ON(gli->mode == MODE_NONE);
- if (--gli->users == 0)
+ if (--gli->users == 0) {
gli->mode = MODE_NONE;
+ cxlflash_ba_terminate(&gli->blka.ba_lun);
+ }
pr_debug("%s: gli->users=%u\n", __func__, gli->users);
WARN_ON(gli->users < 0);
mutex_unlock(&gli->mutex);
@@ -544,10 +567,12 @@ void cxlflash_lun_detach(struct glun_info *gli)
* @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.
+ * For LUNs in virtual mode, the virtual LUN associated with the specified
+ * resource handle is resized to 0 prior to releasing the RHTE. 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
*/
@@ -562,6 +587,7 @@ int _cxlflash_disk_release(struct scsi_device *sdev,
struct afu *afu = cfg->afu;
bool put_ctx = false;
+ struct dk_cxlflash_resize size;
res_hndl_t rhndl = release->rsrc_handle;
int rc = 0;
@@ -594,7 +620,24 @@ int _cxlflash_disk_release(struct scsi_device *sdev,
goto out;
}
+ /*
+ * Resize to 0 for virtual LUNS by setting the size
+ * to 0. This will clear LXT_START and LXT_CNT fields
+ * in the RHT entry and properly sync with the AFU.
+ *
+ * Afterwards we clear the remaining fields.
+ */
switch (gli->mode) {
+ case MODE_VIRTUAL:
+ marshal_rele_to_resize(release, &size);
+ size.req_size = 0;
+ rc = _cxlflash_vlun_resize(sdev, ctxi, &size);
+ if (rc) {
+ dev_dbg(dev, "%s: resize failed rc %d\n", __func__, rc);
+ goto out;
+ }
+
+ break;
case MODE_PHYSICAL:
/*
* Clear the Format 1 RHT entry for direct access
@@ -666,6 +709,7 @@ static void destroy_context(struct cxlflash_cfg *cfg,
/* Free memory associated with context */
free_page((ulong)ctxi->rht_start);
+ kfree(ctxi->rht_needs_ws);
kfree(ctxi->rht_lun);
kfree(ctxi);
atomic_dec_if_positive(&cfg->num_user_contexts);
@@ -693,11 +737,13 @@ static struct ctx_info *create_context(struct cxlflash_cfg *cfg,
struct afu *afu = cfg->afu;
struct ctx_info *ctxi = NULL;
struct llun_info **lli = NULL;
+ bool *ws = 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)) {
+ ws = kzalloc((MAX_RHT_PER_CONTEXT * sizeof(*ws)), GFP_KERNEL);
+ if (unlikely(!ctxi || !lli || !ws)) {
dev_err(dev, "%s: Unable to allocate context!\n", __func__);
goto err;
}
@@ -709,6 +755,7 @@ static struct ctx_info *create_context(struct cxlflash_cfg *cfg,
}
ctxi->rht_lun = lli;
+ ctxi->rht_needs_ws = ws;
ctxi->rht_start = rhte;
ctxi->rht_perms = perms;
@@ -728,6 +775,7 @@ out:
return ctxi;
err:
+ kfree(ws);
kfree(lli);
kfree(ctxi);
ctxi = NULL;
@@ -1729,6 +1777,12 @@ static int cxlflash_disk_verify(struct scsi_device *sdev,
case MODE_PHYSICAL:
last_lba = gli->max_lba;
break;
+ case MODE_VIRTUAL:
+ /* Cast lxt_cnt to u64 for multiply to be treated as 64bit op */
+ last_lba = ((u64)rhte->lxt_cnt * MC_CHUNK_SIZE * gli->blk_len);
+ last_lba /= CXLFLASH_BLOCK_SIZE;
+ last_lba--;
+ break;
default:
WARN(1, "Unsupported LUN mode!");
}
@@ -1756,12 +1810,18 @@ static char *decode_ioctl(int cmd)
return __stringify_1(DK_CXLFLASH_ATTACH);
case DK_CXLFLASH_USER_DIRECT:
return __stringify_1(DK_CXLFLASH_USER_DIRECT);
+ case DK_CXLFLASH_USER_VIRTUAL:
+ return __stringify_1(DK_CXLFLASH_USER_VIRTUAL);
+ case DK_CXLFLASH_VLUN_RESIZE:
+ return __stringify_1(DK_CXLFLASH_VLUN_RESIZE);
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_VLUN_CLONE:
+ return __stringify_1(DK_CXLFLASH_VLUN_CLONE);
case DK_CXLFLASH_RECOVER_AFU:
return __stringify_1(DK_CXLFLASH_RECOVER_AFU);
case DK_CXLFLASH_MANAGE_LUN:
@@ -1876,6 +1936,7 @@ static int ioctl_common(struct scsi_device *sdev, int cmd)
rc = check_state(cfg);
if (unlikely(rc) && (cfg->state == STATE_FAILTERM)) {
switch (cmd) {
+ case DK_CXLFLASH_VLUN_RESIZE:
case DK_CXLFLASH_RELEASE:
case DK_CXLFLASH_DETACH:
dev_dbg(dev, "%s: Command override! (%d)\n",
@@ -1923,12 +1984,18 @@ int cxlflash_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
{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},
+ {sizeof(struct dk_cxlflash_uvirtual), cxlflash_disk_virtual_open},
+ {sizeof(struct dk_cxlflash_resize), (sioctl)cxlflash_vlun_resize},
+ {sizeof(struct dk_cxlflash_clone), (sioctl)cxlflash_disk_clone},
};
/* Restrict command set to physical support only for internal LUN */
if (afu->internal_lun)
switch (cmd) {
case DK_CXLFLASH_RELEASE:
+ case DK_CXLFLASH_USER_VIRTUAL:
+ case DK_CXLFLASH_VLUN_RESIZE:
+ case DK_CXLFLASH_VLUN_CLONE:
dev_dbg(dev, "%s: %s not supported for lun_mode=%d\n",
__func__, decode_ioctl(cmd), afu->internal_lun);
rc = -EINVAL;
@@ -1942,6 +2009,9 @@ int cxlflash_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
case DK_CXLFLASH_DETACH:
case DK_CXLFLASH_VERIFY:
case DK_CXLFLASH_RECOVER_AFU:
+ case DK_CXLFLASH_USER_VIRTUAL:
+ case DK_CXLFLASH_VLUN_RESIZE:
+ case DK_CXLFLASH_VLUN_CLONE:
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);
@@ -31,9 +31,11 @@ extern struct cxlflash_global global;
#define MC_DISCOVERY_TIMEOUT 5 /* 5 secs */
#define CHAN2PORT(_x) ((_x) + 1)
+#define PORT2CHAN(_x) ((_x) - 1)
enum lun_mode {
MODE_NONE = 0,
+ MODE_VIRTUAL,
MODE_PHYSICAL
};
@@ -41,13 +43,14 @@ enum lun_mode {
struct glun_info {
u64 max_lba; /* from read cap(16) */
u32 blk_len; /* from read cap(16) */
- enum lun_mode mode; /* NONE, PHYSICAL */
+ enum lun_mode mode; /* NONE, VIRTUAL, PHYSICAL */
int users; /* Number of users w/ references to LUN */
u8 wwid[16];
struct mutex mutex;
+ struct blka blka;
struct list_head list;
};
@@ -58,6 +61,7 @@ struct llun_info {
u32 host_no; /* host_no from Scsi_host */
u32 port_sel; /* What port to use for this LUN */
bool newly_created; /* Whether the LUN was just discovered */
+ bool in_table; /* Whether a LUN table entry was created */
u8 wwid[16]; /* Keep a duplicate copy here? */
@@ -90,6 +94,7 @@ struct ctx_info {
u32 rht_out; /* Number of checked out RHT entries */
u32 rht_perms; /* User-defined permissions for RHT entries */
struct llun_info **rht_lun; /* Mapping of RHT entries to LUNs */
+ bool *rht_needs_ws; /* User-desired write-same function per RHTE */
struct cxl_ioctl_start_work work;
u64 ctxid;
@@ -111,10 +116,18 @@ struct cxlflash_global {
struct page *err_page; /* One page of all 0xF for error notification */
};
+int cxlflash_vlun_resize(struct scsi_device *, struct dk_cxlflash_resize *);
+int _cxlflash_vlun_resize(struct scsi_device *, struct ctx_info *,
+ struct dk_cxlflash_resize *);
+
int cxlflash_disk_release(struct scsi_device *, struct dk_cxlflash_release *);
int _cxlflash_disk_release(struct scsi_device *, struct ctx_info *,
struct dk_cxlflash_release *);
+int cxlflash_disk_clone(struct scsi_device *, struct dk_cxlflash_clone *);
+
+int cxlflash_disk_virtual_open(struct scsi_device *, void *);
+
int cxlflash_lun_attach(struct glun_info *, enum lun_mode, bool);
void cxlflash_lun_detach(struct glun_info *);
@@ -127,6 +140,8 @@ struct sisl_rht_entry *get_rhte(struct ctx_info *, res_hndl_t,
struct sisl_rht_entry *rhte_checkout(struct ctx_info *, struct llun_info *);
void rhte_checkin(struct ctx_info *, struct sisl_rht_entry *);
+void cxlflash_ba_terminate(struct ba_lun *);
+
int cxlflash_manage_lun(struct scsi_device *, struct dk_cxlflash_manage_lun *);
#endif /* ifndef _CXLFLASH_SUPERPIPE_H */
new file mode 100644
@@ -0,0 +1,1243 @@
+/*
+ * 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/syscalls.h>
+#include <misc/cxl.h>
+#include <asm/unaligned.h>
+#include <asm/bitsperlong.h>
+
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+#include <uapi/scsi/cxlflash_ioctl.h>
+
+#include "sislite.h"
+#include "common.h"
+#include "vlun.h"
+#include "superpipe.h"
+
+/**
+ * marshal_virt_to_resize() - translate uvirtual to resize structure
+ * @virt: Source structure from which to translate/copy.
+ * @resize: Destination structure for the translate/copy.
+ */
+static void marshal_virt_to_resize(struct dk_cxlflash_uvirtual *virt,
+ struct dk_cxlflash_resize *resize)
+{
+ resize->hdr = virt->hdr;
+ resize->context_id = virt->context_id;
+ resize->rsrc_handle = virt->rsrc_handle;
+ resize->req_size = virt->lun_size;
+ resize->last_lba = virt->last_lba;
+}
+
+/**
+ * marshal_clone_to_rele() - translate clone to release structure
+ * @clone: Source structure from which to translate/copy.
+ * @rele: Destination structure for the translate/copy.
+ */
+static void marshal_clone_to_rele(struct dk_cxlflash_clone *clone,
+ struct dk_cxlflash_release *release)
+{
+ release->hdr = clone->hdr;
+ release->context_id = clone->context_id_dst;
+}
+
+/**
+ * ba_init() - initializes a block allocator
+ * @ba_lun: Block allocator to initialize.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ba_init(struct ba_lun *ba_lun)
+{
+ struct ba_lun_info *bali = NULL;
+ int lun_size_au = 0, i = 0;
+ int last_word_underflow = 0;
+ u64 *lam;
+
+ pr_debug("%s: Initializing LUN: lun_id = %llX, "
+ "ba_lun->lsize = %lX, ba_lun->au_size = %lX\n",
+ __func__, ba_lun->lun_id, ba_lun->lsize, ba_lun->au_size);
+
+ /* Calculate bit map size */
+ lun_size_au = ba_lun->lsize / ba_lun->au_size;
+ if (lun_size_au == 0) {
+ pr_debug("%s: Requested LUN size of 0!\n", __func__);
+ return -EINVAL;
+ }
+
+ /* Allocate lun information container */
+ bali = kzalloc(sizeof(struct ba_lun_info), GFP_KERNEL);
+ if (unlikely(!bali)) {
+ pr_err("%s: Failed to allocate lun_info for lun_id %llX\n",
+ __func__, ba_lun->lun_id);
+ return -ENOMEM;
+ }
+
+ bali->total_aus = lun_size_au;
+ bali->lun_bmap_size = lun_size_au / BITS_PER_LONG;
+
+ if (lun_size_au % BITS_PER_LONG)
+ bali->lun_bmap_size++;
+
+ /* Allocate bitmap space */
+ bali->lun_alloc_map = kzalloc((bali->lun_bmap_size * sizeof(u64)),
+ GFP_KERNEL);
+ if (unlikely(!bali->lun_alloc_map)) {
+ pr_err("%s: Failed to allocate lun allocation map: "
+ "lun_id = %llX\n", __func__, ba_lun->lun_id);
+ kfree(bali);
+ return -ENOMEM;
+ }
+
+ /* Initialize the bit map size and set all bits to '1' */
+ bali->free_aun_cnt = lun_size_au;
+
+ for (i = 0; i < bali->lun_bmap_size; i++)
+ bali->lun_alloc_map[i] = 0xFFFFFFFFFFFFFFFFULL;
+
+ /* If the last word not fully utilized, mark extra bits as allocated */
+ last_word_underflow = (bali->lun_bmap_size * BITS_PER_LONG);
+ last_word_underflow -= bali->free_aun_cnt;
+ if (last_word_underflow > 0) {
+ lam = &bali->lun_alloc_map[bali->lun_bmap_size - 1];
+ for (i = (HIBIT - last_word_underflow + 1);
+ i < BITS_PER_LONG;
+ i++)
+ clear_bit(i, (ulong *)lam);
+ }
+
+ /* Initialize high elevator index, low/curr already at 0 from kzalloc */
+ bali->free_high_idx = bali->lun_bmap_size;
+
+ /* Allocate clone map */
+ bali->aun_clone_map = kzalloc((bali->total_aus * sizeof(u8)),
+ GFP_KERNEL);
+ if (unlikely(!bali->aun_clone_map)) {
+ pr_err("%s: Failed to allocate clone map: lun_id = %llX\n",
+ __func__, ba_lun->lun_id);
+ kfree(bali->lun_alloc_map);
+ kfree(bali);
+ return -ENOMEM;
+ }
+
+ /* Pass the allocated lun info as a handle to the user */
+ ba_lun->ba_lun_handle = bali;
+
+ pr_debug("%s: Successfully initialized the LUN: "
+ "lun_id = %llX, bitmap size = %X, free_aun_cnt = %llX\n",
+ __func__, ba_lun->lun_id, bali->lun_bmap_size,
+ bali->free_aun_cnt);
+ return 0;
+}
+
+/**
+ * find_free_range() - locates a free bit within the block allocator
+ * @low: First word in block allocator to start search.
+ * @high: Last word in block allocator to search.
+ * @bali: LUN information structure owning the block allocator to search.
+ * @bit_word: Passes back the word in the block allocator owning the free bit.
+ *
+ * Return: The bit position within the passed back word, -1 on failure
+ */
+static int find_free_range(u32 low,
+ u32 high,
+ struct ba_lun_info *bali, int *bit_word)
+{
+ int i;
+ u64 bit_pos = -1;
+ ulong *lam, num_bits;
+
+ for (i = low; i < high; i++)
+ if (bali->lun_alloc_map[i] != 0) {
+ lam = (ulong *)&bali->lun_alloc_map[i];
+ num_bits = (sizeof(*lam) * BITS_PER_BYTE);
+ bit_pos = find_first_bit(lam, num_bits);
+
+ pr_devel("%s: Found free bit %llX in lun "
+ "map entry %llX at bitmap index = %X\n",
+ __func__, bit_pos, bali->lun_alloc_map[i],
+ i);
+
+ *bit_word = i;
+ bali->free_aun_cnt--;
+ clear_bit(bit_pos, lam);
+ break;
+ }
+
+ return bit_pos;
+}
+
+/**
+ * ba_alloc() - allocates a block from the block allocator
+ * @ba_lun: Block allocator from which to allocate a block.
+ *
+ * Return: The allocated block, -1 on failure
+ */
+static u64 ba_alloc(struct ba_lun *ba_lun)
+{
+ u64 bit_pos = -1;
+ int bit_word = 0;
+ struct ba_lun_info *bali = NULL;
+
+ bali = ba_lun->ba_lun_handle;
+
+ pr_debug("%s: Received block allocation request: "
+ "lun_id = %llX, free_aun_cnt = %llX\n",
+ __func__, ba_lun->lun_id, bali->free_aun_cnt);
+
+ if (bali->free_aun_cnt == 0) {
+ pr_debug("%s: No space left on LUN: lun_id = %llX\n",
+ __func__, ba_lun->lun_id);
+ return -1ULL;
+ }
+
+ /* Search to find a free entry, curr->high then low->curr */
+ bit_pos = find_free_range(bali->free_curr_idx,
+ bali->free_high_idx, bali, &bit_word);
+ if (bit_pos == -1) {
+ bit_pos = find_free_range(bali->free_low_idx,
+ bali->free_curr_idx,
+ bali, &bit_word);
+ if (bit_pos == -1) {
+ pr_debug("%s: Could not find an allocation unit on LUN:"
+ " lun_id = %llX\n", __func__, ba_lun->lun_id);
+ return -1ULL;
+ }
+ }
+
+ /* Update the free_curr_idx */
+ if (bit_pos == HIBIT)
+ bali->free_curr_idx = bit_word + 1;
+ else
+ bali->free_curr_idx = bit_word;
+
+ pr_debug("%s: Allocating AU number %llX, on lun_id %llX, "
+ "free_aun_cnt = %llX\n", __func__,
+ ((bit_word * BITS_PER_LONG) + bit_pos), ba_lun->lun_id,
+ bali->free_aun_cnt);
+
+ return (u64) ((bit_word * BITS_PER_LONG) + bit_pos);
+}
+
+/**
+ * validate_alloc() - validates the specified block has been allocated
+ * @ba_lun_info: LUN info owning the block allocator.
+ * @aun: Block to validate.
+ *
+ * Return: 0 on success, -1 on failure
+ */
+static int validate_alloc(struct ba_lun_info *bali, u64 aun)
+{
+ int idx = 0, bit_pos = 0;
+
+ idx = aun / BITS_PER_LONG;
+ bit_pos = aun % BITS_PER_LONG;
+
+ if (test_bit(bit_pos, (ulong *)&bali->lun_alloc_map[idx]))
+ return -1;
+
+ return 0;
+}
+
+/**
+ * ba_free() - frees a block from the block allocator
+ * @ba_lun: Block allocator from which to allocate a block.
+ * @to_free: Block to free.
+ *
+ * Return: 0 on success, -1 on failure
+ */
+static int ba_free(struct ba_lun *ba_lun, u64 to_free)
+{
+ int idx = 0, bit_pos = 0;
+ struct ba_lun_info *bali = NULL;
+
+ bali = ba_lun->ba_lun_handle;
+
+ if (validate_alloc(bali, to_free)) {
+ pr_debug("%s: The AUN %llX is not allocated on lun_id %llX\n",
+ __func__, to_free, ba_lun->lun_id);
+ return -1;
+ }
+
+ pr_debug("%s: Received a request to free AU %llX on lun_id %llX, "
+ "free_aun_cnt = %llX\n", __func__, to_free, ba_lun->lun_id,
+ bali->free_aun_cnt);
+
+ if (bali->aun_clone_map[to_free] > 0) {
+ pr_debug("%s: AUN %llX on lun_id %llX has been cloned. Clone "
+ "count = %X\n", __func__, to_free, ba_lun->lun_id,
+ bali->aun_clone_map[to_free]);
+ bali->aun_clone_map[to_free]--;
+ return 0;
+ }
+
+ idx = to_free / BITS_PER_LONG;
+ bit_pos = to_free % BITS_PER_LONG;
+
+ set_bit(bit_pos, (ulong *)&bali->lun_alloc_map[idx]);
+ bali->free_aun_cnt++;
+
+ if (idx < bali->free_low_idx)
+ bali->free_low_idx = idx;
+ else if (idx > bali->free_high_idx)
+ bali->free_high_idx = idx;
+
+ pr_debug("%s: Successfully freed AU at bit_pos %X, bit map index %X on "
+ "lun_id %llX, free_aun_cnt = %llX\n", __func__, bit_pos, idx,
+ ba_lun->lun_id, bali->free_aun_cnt);
+
+ return 0;
+}
+
+/**
+ * ba_clone() - Clone a chunk of the block allocation table
+ * @ba_lun: Block allocator from which to allocate a block.
+ * @to_free: Block to free.
+ *
+ * Return: 0 on success, -1 on failure
+ */
+static int ba_clone(struct ba_lun *ba_lun, u64 to_clone)
+{
+ struct ba_lun_info *bali = ba_lun->ba_lun_handle;
+
+ if (validate_alloc(bali, to_clone)) {
+ pr_debug("%s: AUN %llX is not allocated on lun_id %llX\n",
+ __func__, to_clone, ba_lun->lun_id);
+ return -1;
+ }
+
+ pr_debug("%s: Received a request to clone AUN %llX on lun_id %llX\n",
+ __func__, to_clone, ba_lun->lun_id);
+
+ if (bali->aun_clone_map[to_clone] == MAX_AUN_CLONE_CNT) {
+ pr_debug("%s: AUN %llX on lun_id %llX hit max clones already\n",
+ __func__, to_clone, ba_lun->lun_id);
+ return -1;
+ }
+
+ bali->aun_clone_map[to_clone]++;
+
+ return 0;
+}
+
+/**
+ * ba_space() - returns the amount of free space left in the block allocator
+ * @ba_lun: Block allocator.
+ *
+ * Return: Amount of free space in block allocator
+ */
+static u64 ba_space(struct ba_lun *ba_lun)
+{
+ struct ba_lun_info *bali = ba_lun->ba_lun_handle;
+
+ return bali->free_aun_cnt;
+}
+
+/**
+ * cxlflash_ba_terminate() - frees resources associated with the block allocator
+ * @ba_lun: Block allocator.
+ *
+ * Safe to call in a partially allocated state.
+ */
+void cxlflash_ba_terminate(struct ba_lun *ba_lun)
+{
+ struct ba_lun_info *bali = ba_lun->ba_lun_handle;
+
+ if (bali) {
+ kfree(bali->aun_clone_map);
+ kfree(bali->lun_alloc_map);
+ kfree(bali);
+ ba_lun->ba_lun_handle = NULL;
+ }
+}
+
+/**
+ * init_vlun() - initializes a LUN for virtual use
+ * @lun_info: LUN information structure that owns the block allocator.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int init_vlun(struct llun_info *lli)
+{
+ int rc = 0;
+ struct glun_info *gli = lli->parent;
+ struct blka *blka = &gli->blka;
+
+ memset(blka, 0, sizeof(*blka));
+ mutex_init(&blka->mutex);
+
+ /* LUN IDs are unique per port, save the index instead */
+ blka->ba_lun.lun_id = lli->lun_index;
+ blka->ba_lun.lsize = gli->max_lba + 1;
+ blka->ba_lun.lba_size = gli->blk_len;
+
+ blka->ba_lun.au_size = MC_CHUNK_SIZE;
+ blka->nchunk = blka->ba_lun.lsize / MC_CHUNK_SIZE;
+
+ rc = ba_init(&blka->ba_lun);
+ if (unlikely(rc))
+ pr_debug("%s: cannot init block_alloc, rc=%d\n", __func__, rc);
+
+ pr_debug("%s: returning rc=%d lli=%p\n", __func__, rc, lli);
+ return rc;
+}
+
+/**
+ * write_same16() - sends a SCSI WRITE_SAME16 (0) command to specified LUN
+ * @sdev: SCSI device associated with LUN.
+ * @lba: Logical block address to start write same.
+ * @nblks: Number of logical blocks to write same.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int write_same16(struct scsi_device *sdev,
+ u64 lba,
+ u32 nblks)
+{
+ u8 *cmd_buf = NULL;
+ u8 *scsi_cmd = NULL;
+ u8 *sense_buf = NULL;
+ int rc = 0;
+ int result = 0;
+ int ws_limit = SISLITE_MAX_WS_BLOCKS;
+ u64 offset = lba;
+ int left = nblks;
+ u32 tout = sdev->request_queue->rq_timeout;
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+
+ 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;
+ }
+
+ while (left > 0) {
+
+ scsi_cmd[0] = WRITE_SAME_16;
+ put_unaligned_be64(offset, &scsi_cmd[2]);
+ put_unaligned_be32(ws_limit < left ? ws_limit : left,
+ &scsi_cmd[10]);
+
+ result = scsi_execute(sdev, scsi_cmd, DMA_TO_DEVICE, cmd_buf,
+ CMD_BUFSIZE, sense_buf, tout, 5, 0, NULL);
+ if (result) {
+ dev_err_ratelimited(dev, "%s: command failed for "
+ "offset %lld result=0x%x\n",
+ __func__, offset, result);
+ rc = -EIO;
+ goto out;
+ }
+ left -= ws_limit;
+ offset += ws_limit;
+ }
+
+out:
+ kfree(cmd_buf);
+ kfree(scsi_cmd);
+ kfree(sense_buf);
+ pr_debug("%s: returning rc=%d\n", __func__, rc);
+ return rc;
+}
+
+/**
+ * grow_lxt() - expands the translation table associated with the specified RHTE
+ * @afu: AFU associated with the host.
+ * @sdev: SCSI device associated with LUN.
+ * @ctxid: Context ID of context owning the RHTE.
+ * @rhndl: Resource handle associated with the RHTE.
+ * @rhte: Resource handle entry (RHTE).
+ * @new_size: Number of translation entries associated with RHTE.
+ *
+ * By design, this routine employs a 'best attempt' allocation and will
+ * truncate the requested size down if there is not sufficient space in
+ * the block allocator to satisfy the request but there does exist some
+ * amount of space. The user is made aware of this by returning the size
+ * allocated.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int grow_lxt(struct afu *afu,
+ struct scsi_device *sdev,
+ ctx_hndl_t ctxid,
+ res_hndl_t rhndl,
+ struct sisl_rht_entry *rhte,
+ u64 *new_size)
+{
+ struct sisl_lxt_entry *lxt = NULL, *lxt_old = NULL;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+ struct blka *blka = &gli->blka;
+ u32 av_size;
+ u32 ngrps, ngrps_old;
+ u64 aun; /* chunk# allocated by block allocator */
+ u64 delta = *new_size - rhte->lxt_cnt;
+ u64 my_new_size;
+ int i, rc = 0;
+
+ /*
+ * Check what is available in the block allocator before re-allocating
+ * LXT array. This is done up front under the mutex which must not be
+ * released until after allocation is complete.
+ */
+ mutex_lock(&blka->mutex);
+ av_size = ba_space(&blka->ba_lun);
+ if (unlikely(av_size <= 0)) {
+ pr_debug("%s: ba_space error: av_size %d\n", __func__, av_size);
+ mutex_unlock(&blka->mutex);
+ rc = -ENOSPC;
+ goto out;
+ }
+
+ if (av_size < delta)
+ delta = av_size;
+
+ lxt_old = rhte->lxt_start;
+ ngrps_old = LXT_NUM_GROUPS(rhte->lxt_cnt);
+ ngrps = LXT_NUM_GROUPS(rhte->lxt_cnt + delta);
+
+ if (ngrps != ngrps_old) {
+ /* reallocate to fit new size */
+ lxt = kzalloc((sizeof(*lxt) * LXT_GROUP_SIZE * ngrps),
+ GFP_KERNEL);
+ if (unlikely(!lxt)) {
+ mutex_unlock(&blka->mutex);
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ /* copy over all old entries */
+ memcpy(lxt, lxt_old, (sizeof(*lxt) * rhte->lxt_cnt));
+ } else
+ lxt = lxt_old;
+
+ /* nothing can fail from now on */
+ my_new_size = rhte->lxt_cnt + delta;
+
+ /* add new entries to the end */
+ for (i = rhte->lxt_cnt; i < my_new_size; i++) {
+ /*
+ * Due to the earlier check of available space, ba_alloc
+ * cannot fail here. If it did due to internal error,
+ * leave a rlba_base of -1u which will likely be a
+ * invalid LUN (too large).
+ */
+ aun = ba_alloc(&blka->ba_lun);
+ if ((aun == -1ULL) || (aun >= blka->nchunk))
+ pr_debug("%s: ba_alloc error: allocated chunk# %llX, "
+ "max %llX\n", __func__, aun, blka->nchunk - 1);
+
+ /* select both ports, use r/w perms from RHT */
+ lxt[i].rlba_base = ((aun << MC_CHUNK_SHIFT) |
+ (lli->lun_index << LXT_LUNIDX_SHIFT) |
+ (RHT_PERM_RW << LXT_PERM_SHIFT |
+ lli->port_sel));
+ }
+
+ mutex_unlock(&blka->mutex);
+
+ /*
+ * The following sequence is prescribed in the SISlite spec
+ * for syncing up with the AFU when adding LXT entries.
+ */
+ dma_wmb(); /* Make LXT updates are visible */
+
+ rhte->lxt_start = lxt;
+ dma_wmb(); /* Make RHT entry's LXT table update visible */
+
+ rhte->lxt_cnt = my_new_size;
+ dma_wmb(); /* Make RHT entry's LXT table size update visible */
+
+ cxlflash_afu_sync(afu, ctxid, rhndl, AFU_LW_SYNC);
+
+ /* free old lxt if reallocated */
+ if (lxt != lxt_old)
+ kfree(lxt_old);
+ *new_size = my_new_size;
+out:
+ pr_debug("%s: returning rc=%d\n", __func__, rc);
+ return rc;
+}
+
+/**
+ * shrink_lxt() - reduces translation table associated with the specified RHTE
+ * @afu: AFU associated with the host.
+ * @sdev: SCSI device associated with LUN.
+ * @rhndl: Resource handle associated with the RHTE.
+ * @rhte: Resource handle entry (RHTE).
+ * @ctxi: Context owning resources.
+ * @new_size: Number of translation entries associated with RHTE.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int shrink_lxt(struct afu *afu,
+ struct scsi_device *sdev,
+ res_hndl_t rhndl,
+ struct sisl_rht_entry *rhte,
+ struct ctx_info *ctxi,
+ u64 *new_size)
+{
+ struct sisl_lxt_entry *lxt, *lxt_old;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+ struct blka *blka = &gli->blka;
+ ctx_hndl_t ctxid = DECODE_CTXID(ctxi->ctxid);
+ bool needs_ws = ctxi->rht_needs_ws[rhndl];
+ bool needs_sync = !ctxi->err_recovery_active;
+ u32 ngrps, ngrps_old;
+ u64 aun; /* chunk# allocated by block allocator */
+ u64 delta = rhte->lxt_cnt - *new_size;
+ u64 my_new_size;
+ int i, rc = 0;
+
+ lxt_old = rhte->lxt_start;
+ ngrps_old = LXT_NUM_GROUPS(rhte->lxt_cnt);
+ ngrps = LXT_NUM_GROUPS(rhte->lxt_cnt - delta);
+
+ if (ngrps != ngrps_old) {
+ /* Reallocate to fit new size unless new size is 0 */
+ if (ngrps) {
+ lxt = kzalloc((sizeof(*lxt) * LXT_GROUP_SIZE * ngrps),
+ GFP_KERNEL);
+ if (unlikely(!lxt)) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ /* Copy over old entries that will remain */
+ memcpy(lxt, lxt_old,
+ (sizeof(*lxt) * (rhte->lxt_cnt - delta)));
+ } else
+ lxt = NULL;
+ } else
+ lxt = lxt_old;
+
+ /* Nothing can fail from now on */
+ my_new_size = rhte->lxt_cnt - delta;
+
+ /*
+ * The following sequence is prescribed in the SISlite spec
+ * for syncing up with the AFU when removing LXT entries.
+ */
+ rhte->lxt_cnt = my_new_size;
+ dma_wmb(); /* Make RHT entry's LXT table size update visible */
+
+ rhte->lxt_start = lxt;
+ dma_wmb(); /* Make RHT entry's LXT table update visible */
+
+ if (needs_sync)
+ cxlflash_afu_sync(afu, ctxid, rhndl, AFU_HW_SYNC);
+
+ if (needs_ws) {
+ /*
+ * Mark the context as unavailable, so that we can release
+ * the mutex safely.
+ */
+ ctxi->unavail = true;
+ mutex_unlock(&ctxi->mutex);
+ }
+
+ /* Free LBAs allocated to freed chunks */
+ mutex_lock(&blka->mutex);
+ for (i = delta - 1; i >= 0; i--) {
+ /* Mask the higher 48 bits before shifting, even though
+ * it is a noop
+ */
+ aun = (lxt_old[my_new_size + i].rlba_base & SISL_ASTATUS_MASK);
+ aun = (aun >> MC_CHUNK_SHIFT);
+ if (needs_ws)
+ write_same16(sdev, aun, MC_CHUNK_SIZE);
+ ba_free(&blka->ba_lun, aun);
+ }
+ mutex_unlock(&blka->mutex);
+
+ if (needs_ws) {
+ /* Make the context visible again */
+ mutex_lock(&ctxi->mutex);
+ ctxi->unavail = false;
+ }
+
+ /* Free old lxt if reallocated */
+ if (lxt != lxt_old)
+ kfree(lxt_old);
+ *new_size = my_new_size;
+out:
+ pr_debug("%s: returning rc=%d\n", __func__, rc);
+ return rc;
+}
+
+/**
+ * _cxlflash_vlun_resize() - changes the size of a virtual lun
+ * @sdev: SCSI device associated with LUN owning virtual LUN.
+ * @ctxi: Context owning resources.
+ * @resize: Resize ioctl data structure.
+ *
+ * On successful return, the user is informed of the new size (in blocks)
+ * of the virtual lun in last LBA format. When the size of the virtual
+ * lun is zero, the last LBA is reflected as -1. See comment in the
+ * prologue for _cxlflash_disk_release() regarding AFU syncs and contexts
+ * on the error recovery list.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+int _cxlflash_vlun_resize(struct scsi_device *sdev,
+ struct ctx_info *ctxi,
+ struct dk_cxlflash_resize *resize)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ 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 = resize->rsrc_handle;
+ u64 new_size;
+ u64 nsectors;
+ u64 ctxid = DECODE_CTXID(resize->context_id),
+ rctxid = resize->context_id;
+
+ struct sisl_rht_entry *rhte;
+
+ int rc = 0;
+
+ /*
+ * The requested size (req_size) is always assumed to be in 4k blocks,
+ * so we have to convert it here from 4k to chunk size.
+ */
+ nsectors = (resize->req_size * CXLFLASH_BLOCK_SIZE) / gli->blk_len;
+ new_size = DIV_ROUND_UP(nsectors, MC_CHUNK_SIZE);
+
+ pr_debug("%s: ctxid=%llu rhndl=0x%llx, req_size=0x%llx,"
+ "new_size=%llx\n", __func__, ctxid, resize->rsrc_handle,
+ resize->req_size, new_size);
+
+ if (unlikely(gli->mode != MODE_VIRTUAL)) {
+ pr_debug("%s: LUN mode does not support resize! (%d)\n",
+ __func__, gli->mode);
+ rc = -EINVAL;
+ goto out;
+
+ }
+
+ if (!ctxi) {
+ ctxi = get_context(cfg, rctxid, lli, CTX_CTRL_ERR_FALLBACK);
+ if (unlikely(!ctxi)) {
+ pr_debug("%s: Bad context! (%llu)\n", __func__, ctxid);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ put_ctx = true;
+ }
+
+ rhte = get_rhte(ctxi, rhndl, lli);
+ if (unlikely(!rhte)) {
+ pr_debug("%s: Bad resource handle! (%u)\n", __func__, rhndl);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if (new_size > rhte->lxt_cnt)
+ rc = grow_lxt(afu, sdev, ctxid, rhndl, rhte, &new_size);
+ else if (new_size < rhte->lxt_cnt)
+ rc = shrink_lxt(afu, sdev, rhndl, rhte, ctxi, &new_size);
+
+ resize->hdr.return_flags = 0;
+ resize->last_lba = (new_size * MC_CHUNK_SIZE * gli->blk_len);
+ resize->last_lba /= CXLFLASH_BLOCK_SIZE;
+ resize->last_lba--;
+
+out:
+ if (put_ctx)
+ put_context(ctxi);
+ pr_debug("%s: resized to %lld returning rc=%d\n",
+ __func__, resize->last_lba, rc);
+ return rc;
+}
+
+int cxlflash_vlun_resize(struct scsi_device *sdev,
+ struct dk_cxlflash_resize *resize)
+{
+ return _cxlflash_vlun_resize(sdev, NULL, resize);
+}
+
+/**
+ * cxlflash_restore_luntable() - Restore LUN table to prior state
+ * @cfg: Internal structure associated with the host.
+ */
+void cxlflash_restore_luntable(struct cxlflash_cfg *cfg)
+{
+ struct llun_info *lli, *temp;
+ u32 chan;
+ u32 lind;
+ struct afu *afu = cfg->afu;
+ struct sisl_global_map *agm = &afu->afu_map->global;
+
+ mutex_lock(&global.mutex);
+
+ list_for_each_entry_safe(lli, temp, &cfg->lluns, list) {
+ if (!lli->in_table)
+ continue;
+
+ lind = lli->lun_index;
+
+ if (lli->port_sel == BOTH_PORTS) {
+ writeq_be(lli->lun_id[0], &agm->fc_port[0][lind]);
+ writeq_be(lli->lun_id[1], &agm->fc_port[1][lind]);
+ pr_debug("%s: Virtual LUN on slot %d id0=%llx, "
+ "id1=%llx\n", __func__, lind,
+ lli->lun_id[0], lli->lun_id[1]);
+ } else {
+ chan = PORT2CHAN(lli->port_sel);
+ writeq_be(lli->lun_id[chan], &agm->fc_port[chan][lind]);
+ pr_debug("%s: Virtual LUN on slot %d chan=%d, "
+ "id=%llx\n", __func__, lind, chan,
+ lli->lun_id[chan]);
+ }
+ }
+
+ mutex_unlock(&global.mutex);
+}
+
+/**
+ * init_luntable() - write an entry in the LUN table
+ * @cfg: Internal structure associated with the host.
+ * @lli: Per adapter LUN information structure.
+ *
+ * On successful return, a LUN table entry is created.
+ * At the top for LUNs visible on both ports.
+ * At the bottom for LUNs visible only on one port.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int init_luntable(struct cxlflash_cfg *cfg, struct llun_info *lli)
+{
+ u32 chan;
+ u32 lind;
+ int rc = 0;
+ struct afu *afu = cfg->afu;
+ struct sisl_global_map *agm = &afu->afu_map->global;
+
+ mutex_lock(&global.mutex);
+
+ if (lli->in_table)
+ goto out;
+
+ if (lli->port_sel == BOTH_PORTS) {
+ /*
+ * If this LUN is visible from both ports, we will put
+ * it in the top half of the LUN table.
+ */
+ if ((cfg->promote_lun_index == cfg->last_lun_index[0]) ||
+ (cfg->promote_lun_index == cfg->last_lun_index[1])) {
+ rc = -ENOSPC;
+ goto out;
+ }
+
+ lind = lli->lun_index = cfg->promote_lun_index;
+ writeq_be(lli->lun_id[0], &agm->fc_port[0][lind]);
+ writeq_be(lli->lun_id[1], &agm->fc_port[1][lind]);
+ cfg->promote_lun_index++;
+ pr_debug("%s: Virtual LUN on slot %d id0=%llx, id1=%llx\n",
+ __func__, lind, lli->lun_id[0], lli->lun_id[1]);
+ } else {
+ /*
+ * If this LUN is visible only from one port, we will put
+ * it in the bottom half of the LUN table.
+ */
+ chan = PORT2CHAN(lli->port_sel);
+ if (cfg->promote_lun_index == cfg->last_lun_index[chan]) {
+ rc = -ENOSPC;
+ goto out;
+ }
+
+ lind = lli->lun_index = cfg->last_lun_index[chan];
+ writeq_be(lli->lun_id[chan], &agm->fc_port[chan][lind]);
+ cfg->last_lun_index[chan]--;
+ pr_debug("%s: Virtual LUN on slot %d chan=%d, id=%llx\n",
+ __func__, lind, chan, lli->lun_id[chan]);
+ }
+
+ lli->in_table = true;
+out:
+ mutex_unlock(&global.mutex);
+ pr_debug("%s: returning rc=%d\n", __func__, rc);
+ return rc;
+}
+
+/**
+ * cxlflash_disk_virtual_open() - open a virtual disk of specified size
+ * @sdev: SCSI device associated with LUN owning virtual LUN.
+ * @arg: UVirtual ioctl data structure.
+ *
+ * On successful return, the user is informed of the resource handle
+ * to be used to identify the virtual lun and the size (in blocks) of
+ * the virtual lun in last LBA format. When the size of the virtual lun
+ * is zero, the last LBA is reflected as -1.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+int cxlflash_disk_virtual_open(struct scsi_device *sdev, void *arg)
+{
+ 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 dk_cxlflash_uvirtual *virt = (struct dk_cxlflash_uvirtual *)arg;
+ struct dk_cxlflash_resize resize;
+
+ u64 ctxid = DECODE_CTXID(virt->context_id),
+ rctxid = virt->context_id;
+ u64 lun_size = virt->lun_size;
+ u64 last_lba = 0;
+ u64 rsrc_handle = -1;
+
+ 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);
+
+ mutex_lock(&gli->mutex);
+ if (gli->mode == MODE_NONE) {
+ /* Setup the LUN table and block allocator on first call */
+ rc = init_luntable(cfg, lli);
+ if (rc) {
+ dev_err(dev, "%s: call to init_luntable failed "
+ "rc=%d!\n", __func__, rc);
+ goto err0;
+ }
+
+ rc = init_vlun(lli);
+ if (rc) {
+ dev_err(dev, "%s: call to init_vlun failed rc=%d!\n",
+ __func__, rc);
+ rc = -ENOMEM;
+ goto err0;
+ }
+ }
+
+ rc = cxlflash_lun_attach(gli, MODE_VIRTUAL, true);
+ if (unlikely(rc)) {
+ dev_err(dev, "%s: Failed to attach to LUN! (VIRTUAL)\n",
+ __func__);
+ goto err0;
+ }
+ mutex_unlock(&gli->mutex);
+
+ ctxi = get_context(cfg, rctxid, lli, 0);
+ if (unlikely(!ctxi)) {
+ dev_err(dev, "%s: Bad context! (%llu)\n", __func__, ctxid);
+ rc = -EINVAL;
+ goto err1;
+ }
+
+ rhte = rhte_checkout(ctxi, lli);
+ if (unlikely(!rhte)) {
+ dev_err(dev, "%s: too many opens for this context\n", __func__);
+ rc = -EMFILE; /* too many opens */
+ goto err1;
+ }
+
+ rsrc_handle = (rhte - ctxi->rht_start);
+
+ /* Populate RHT format 0 */
+ rhte->nmask = MC_RHT_NMASK;
+ rhte->fp = SISL_RHT_FP(0U, ctxi->rht_perms);
+
+ /* Resize even if requested size is 0 */
+ marshal_virt_to_resize(virt, &resize);
+ resize.rsrc_handle = rsrc_handle;
+ rc = _cxlflash_vlun_resize(sdev, ctxi, &resize);
+ if (rc) {
+ dev_err(dev, "%s: resize failed rc %d\n", __func__, rc);
+ goto err2;
+ }
+ last_lba = resize.last_lba;
+
+ if (virt->hdr.flags & DK_CXLFLASH_UVIRTUAL_NEED_WRITE_SAME)
+ ctxi->rht_needs_ws[rsrc_handle] = true;
+
+ virt->hdr.return_flags = 0;
+ virt->last_lba = last_lba;
+ virt->rsrc_handle = rsrc_handle;
+
+out:
+ if (likely(ctxi))
+ put_context(ctxi);
+ pr_debug("%s: returning handle 0x%llx rc=%d llba %lld\n",
+ __func__, rsrc_handle, rc, last_lba);
+ return rc;
+
+err2:
+ rhte_checkin(ctxi, rhte);
+err1:
+ cxlflash_lun_detach(gli);
+ goto out;
+err0:
+ /* Special common cleanup prior to successful LUN attach */
+ cxlflash_ba_terminate(&gli->blka.ba_lun);
+ mutex_unlock(&gli->mutex);
+ goto out;
+}
+
+/**
+ * clone_lxt() - copies translation tables from source to destination RHTE
+ * @afu: AFU associated with the host.
+ * @blka: Block allocator associated with LUN.
+ * @ctxid: Context ID of context owning the RHTE.
+ * @rhndl: Resource handle associated with the RHTE.
+ * @rhte: Destination resource handle entry (RHTE).
+ * @rhte_src: Source resource handle entry (RHTE).
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int clone_lxt(struct afu *afu,
+ struct blka *blka,
+ ctx_hndl_t ctxid,
+ res_hndl_t rhndl,
+ struct sisl_rht_entry *rhte,
+ struct sisl_rht_entry *rhte_src)
+{
+ struct sisl_lxt_entry *lxt;
+ u32 ngrps;
+ u64 aun; /* chunk# allocated by block allocator */
+ int i, j;
+
+ ngrps = LXT_NUM_GROUPS(rhte_src->lxt_cnt);
+
+ if (ngrps) {
+ /* allocate new LXTs for clone */
+ lxt = kzalloc((sizeof(*lxt) * LXT_GROUP_SIZE * ngrps),
+ GFP_KERNEL);
+ if (unlikely(!lxt))
+ return -ENOMEM;
+
+ /* copy over */
+ memcpy(lxt, rhte_src->lxt_start,
+ (sizeof(*lxt) * rhte_src->lxt_cnt));
+
+ /* clone the LBAs in block allocator via ref_cnt */
+ mutex_lock(&blka->mutex);
+ for (i = 0; i < rhte_src->lxt_cnt; i++) {
+ aun = (lxt[i].rlba_base >> MC_CHUNK_SHIFT);
+ if (ba_clone(&blka->ba_lun, aun) == -1ULL) {
+ /* free the clones already made */
+ for (j = 0; j < i; j++) {
+ aun = (lxt[j].rlba_base >>
+ MC_CHUNK_SHIFT);
+ ba_free(&blka->ba_lun, aun);
+ }
+
+ mutex_unlock(&blka->mutex);
+ kfree(lxt);
+ return -EIO;
+ }
+ }
+ mutex_unlock(&blka->mutex);
+ } else {
+ lxt = NULL;
+ }
+
+ /*
+ * The following sequence is prescribed in the SISlite spec
+ * for syncing up with the AFU when adding LXT entries.
+ */
+ dma_wmb(); /* Make LXT updates are visible */
+
+ rhte->lxt_start = lxt;
+ dma_wmb(); /* Make RHT entry's LXT table update visible */
+
+ rhte->lxt_cnt = rhte_src->lxt_cnt;
+ dma_wmb(); /* Make RHT entry's LXT table size update visible */
+
+ cxlflash_afu_sync(afu, ctxid, rhndl, AFU_LW_SYNC);
+
+ pr_debug("%s: returning\n", __func__);
+ return 0;
+}
+
+/**
+ * cxlflash_disk_clone() - clone a context by making snapshot of another
+ * @sdev: SCSI device associated with LUN owning virtual LUN.
+ * @clone: Clone ioctl data structure.
+ *
+ * This routine effectively performs cxlflash_disk_open operation for each
+ * in-use virtual resource in the source context. Note that the destination
+ * context must be in pristine state and cannot have any resource handles
+ * open at the time of the clone.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+int cxlflash_disk_clone(struct scsi_device *sdev,
+ struct dk_cxlflash_clone *clone)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+ struct blka *blka = &gli->blka;
+ struct afu *afu = cfg->afu;
+ struct dk_cxlflash_release release = { { 0 }, 0 };
+
+ struct ctx_info *ctxi_src = NULL,
+ *ctxi_dst = NULL;
+ struct lun_access *lun_access_src, *lun_access_dst;
+ u32 perms;
+ u64 ctxid_src = DECODE_CTXID(clone->context_id_src),
+ ctxid_dst = DECODE_CTXID(clone->context_id_dst),
+ rctxid_src = clone->context_id_src,
+ rctxid_dst = clone->context_id_dst;
+ int adap_fd_src = clone->adap_fd_src;
+ int i, j;
+ int rc = 0;
+ bool found;
+ LIST_HEAD(sidecar);
+
+ pr_debug("%s: ctxid_src=%llu ctxid_dst=%llu adap_fd_src=%d\n",
+ __func__, ctxid_src, ctxid_dst, adap_fd_src);
+
+ /* Do not clone yourself */
+ if (unlikely(rctxid_src == rctxid_dst)) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if (unlikely(gli->mode != MODE_VIRTUAL)) {
+ rc = -EINVAL;
+ pr_debug("%s: Clone not supported on physical LUNs! (%d)\n",
+ __func__, gli->mode);
+ goto out;
+ }
+
+ ctxi_src = get_context(cfg, rctxid_src, lli, CTX_CTRL_CLONE);
+ ctxi_dst = get_context(cfg, rctxid_dst, lli, 0);
+ if (unlikely(!ctxi_src || !ctxi_dst)) {
+ pr_debug("%s: Bad context! (%llu,%llu)\n", __func__,
+ ctxid_src, ctxid_dst);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if (unlikely(adap_fd_src != ctxi_src->lfd)) {
+ pr_debug("%s: Invalid source adapter fd! (%d)\n",
+ __func__, adap_fd_src);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /* Verify there is no open resource handle in the destination context */
+ for (i = 0; i < MAX_RHT_PER_CONTEXT; i++)
+ if (ctxi_dst->rht_start[i].nmask != 0) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /* Clone LUN access list */
+ list_for_each_entry(lun_access_src, &ctxi_src->luns, list) {
+ found = false;
+ list_for_each_entry(lun_access_dst, &ctxi_dst->luns, list)
+ if (lun_access_dst->sdev == lun_access_src->sdev) {
+ found = true;
+ break;
+ }
+
+ if (!found) {
+ lun_access_dst = kzalloc(sizeof(*lun_access_dst),
+ GFP_KERNEL);
+ if (unlikely(!lun_access_dst)) {
+ pr_err("%s: Unable to allocate lun_access!\n",
+ __func__);
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ *lun_access_dst = *lun_access_src;
+ list_add(&lun_access_dst->list, &sidecar);
+ }
+ }
+
+ if (unlikely(!ctxi_src->rht_out)) {
+ pr_debug("%s: Nothing to clone!\n", __func__);
+ goto out_success;
+ }
+
+ /* User specified permission on attach */
+ perms = ctxi_dst->rht_perms;
+
+ /*
+ * Copy over checked-out RHT (and their associated LXT) entries by
+ * hand, stopping after we've copied all outstanding entries and
+ * cleaning up if the clone fails.
+ *
+ * Note: This loop is equivalent to performing cxlflash_disk_open and
+ * cxlflash_vlun_resize. As such, LUN accounting needs to be taken into
+ * account by attaching after each successful RHT entry clone. In the
+ * event that a clone failure is experienced, the LUN detach is handled
+ * via the cleanup performed by _cxlflash_disk_release.
+ */
+ for (i = 0; i < MAX_RHT_PER_CONTEXT; i++) {
+ if (ctxi_src->rht_out == ctxi_dst->rht_out)
+ break;
+ if (ctxi_src->rht_start[i].nmask == 0)
+ continue;
+
+ /* Consume a destination RHT entry */
+ ctxi_dst->rht_out++;
+ ctxi_dst->rht_start[i].nmask = ctxi_src->rht_start[i].nmask;
+ ctxi_dst->rht_start[i].fp =
+ SISL_RHT_FP_CLONE(ctxi_src->rht_start[i].fp, perms);
+ ctxi_dst->rht_lun[i] = ctxi_src->rht_lun[i];
+
+ rc = clone_lxt(afu, blka, ctxid_dst, i,
+ &ctxi_dst->rht_start[i],
+ &ctxi_src->rht_start[i]);
+ if (rc) {
+ marshal_clone_to_rele(clone, &release);
+ for (j = 0; j < i; j++) {
+ release.rsrc_handle = j;
+ _cxlflash_disk_release(sdev, ctxi_dst,
+ &release);
+ }
+
+ /* Put back the one we failed on */
+ rhte_checkin(ctxi_dst, &ctxi_dst->rht_start[i]);
+ goto err;
+ }
+
+ cxlflash_lun_attach(gli, gli->mode, false);
+ }
+
+out_success:
+ list_splice(&sidecar, &ctxi_dst->luns);
+ sys_close(adap_fd_src);
+
+ /* fall through */
+out:
+ if (ctxi_src)
+ put_context(ctxi_src);
+ if (ctxi_dst)
+ put_context(ctxi_dst);
+ pr_debug("%s: returning rc=%d\n", __func__, rc);
+ return rc;
+
+err:
+ list_for_each_entry_safe(lun_access_src, lun_access_dst, &sidecar, list)
+ kfree(lun_access_src);
+ goto out;
+}
new file mode 100644
@@ -0,0 +1,86 @@
+/*
+ * 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.
+ */
+
+#ifndef _CXLFLASH_VLUN_H
+#define _CXLFLASH_VLUN_H
+
+/* RHT - Resource Handle Table */
+#define MC_RHT_NMASK 16 /* in bits */
+#define MC_CHUNK_SHIFT MC_RHT_NMASK /* shift to go from LBA to chunk# */
+
+#define HIBIT (BITS_PER_LONG - 1)
+
+#define MAX_AUN_CLONE_CNT 0xFF
+
+/*
+ * LXT - LBA Translation Table
+ *
+ * +-------+-------+-------+-------+-------+-------+-------+---+---+
+ * | RLBA_BASE |LUN_IDX| P |SEL|
+ * +-------+-------+-------+-------+-------+-------+-------+---+---+
+ *
+ * The LXT Entry contains the physical LBA where the chunk starts (RLBA_BASE).
+ * AFU ORes the low order bits from the virtual LBA (offset into the chunk)
+ * with RLBA_BASE. The result is the physical LBA to be sent to storage.
+ * The LXT Entry also contains an index to a LUN TBL and a bitmask of which
+ * outgoing (FC) * ports can be selected. The port select bit-mask is ANDed
+ * with a global port select bit-mask maintained by the driver.
+ * In addition, it has permission bits that are ANDed with the
+ * RHT permissions to arrive at the final permissions for the chunk.
+ *
+ * LXT tables are allocated dynamically in groups. This is done to avoid
+ * a malloc/free overhead each time the LXT has to grow or shrink.
+ *
+ * Based on the current lxt_cnt (used), it is always possible to know
+ * how many are allocated (used+free). The number of allocated entries is
+ * not stored anywhere.
+ *
+ * The LXT table is re-allocated whenever it needs to cross into another group.
+*/
+#define LXT_GROUP_SIZE 8
+#define LXT_NUM_GROUPS(lxt_cnt) (((lxt_cnt) + 7)/8) /* alloc'ed groups */
+#define LXT_LUNIDX_SHIFT 8 /* LXT entry, shift for LUN index */
+#define LXT_PERM_SHIFT 4 /* LXT entry, shift for permission bits */
+
+struct ba_lun_info {
+ u64 *lun_alloc_map;
+ u32 lun_bmap_size;
+ u32 total_aus;
+ u64 free_aun_cnt;
+
+ /* indices to be used for elevator lookup of free map */
+ u32 free_low_idx;
+ u32 free_curr_idx;
+ u32 free_high_idx;
+
+ u8 *aun_clone_map;
+};
+
+struct ba_lun {
+ u64 lun_id;
+ u64 wwpn;
+ size_t lsize; /* LUN size in number of LBAs */
+ size_t lba_size; /* LBA size in number of bytes */
+ size_t au_size; /* Allocation Unit size in number of LBAs */
+ struct ba_lun_info *ba_lun_handle;
+};
+
+/* Block Allocator */
+struct blka {
+ struct ba_lun ba_lun;
+ u64 nchunk; /* number of chunks */
+ struct mutex mutex;
+};
+
+#endif /* ifndef _CXLFLASH_SUPERPIPE_H */
@@ -71,6 +71,17 @@ struct dk_cxlflash_udirect {
__u64 reserved[8]; /* Reserved for future use */
};
+#define DK_CXLFLASH_UVIRTUAL_NEED_WRITE_SAME 0x8000000000000000ULL
+
+struct dk_cxlflash_uvirtual {
+ struct dk_cxlflash_hdr hdr; /* Common fields */
+ __u64 context_id; /* Context to own virtual resources */
+ __u64 lun_size; /* Requested size, in 4K blocks */
+ __u64 rsrc_handle; /* Returned resource handle */
+ __u64 last_lba; /* Returned last LBA of LUN */
+ __u64 reserved[8]; /* Reserved for future use */
+};
+
struct dk_cxlflash_release {
struct dk_cxlflash_hdr hdr; /* Common fields */
__u64 context_id; /* Context owning resources */
@@ -78,6 +89,23 @@ struct dk_cxlflash_release {
__u64 reserved[8]; /* Reserved for future use */
};
+struct dk_cxlflash_resize {
+ struct dk_cxlflash_hdr hdr; /* Common fields */
+ __u64 context_id; /* Context owning resources */
+ __u64 rsrc_handle; /* Resource handle of LUN to resize */
+ __u64 req_size; /* New requested size, in 4K blocks */
+ __u64 last_lba; /* Returned last LBA of LUN */
+ __u64 reserved[8]; /* Reserved for future use */
+};
+
+struct dk_cxlflash_clone {
+ struct dk_cxlflash_hdr hdr; /* Common fields */
+ __u64 context_id_src; /* Context to clone from */
+ __u64 context_id_dst; /* Context to clone to */
+ __u64 adap_fd_src; /* Source context adapter fd */
+ __u64 reserved[8]; /* Reserved for future use */
+};
+
#define DK_CXLFLASH_VERIFY_SENSE_LEN 18
#define DK_CXLFLASH_VERIFY_HINT_SENSE 0x8000000000000000ULL
@@ -118,7 +146,10 @@ union cxlflash_ioctls {
struct dk_cxlflash_attach attach;
struct dk_cxlflash_detach detach;
struct dk_cxlflash_udirect udirect;
+ struct dk_cxlflash_uvirtual uvirtual;
struct dk_cxlflash_release release;
+ struct dk_cxlflash_resize resize;
+ struct dk_cxlflash_clone clone;
struct dk_cxlflash_verify verify;
struct dk_cxlflash_recover_afu recover_afu;
struct dk_cxlflash_manage_lun manage_lun;
@@ -136,5 +167,8 @@ union cxlflash_ioctls {
#define DK_CXLFLASH_VERIFY CXL_IOWR(0x84, dk_cxlflash_verify)
#define DK_CXLFLASH_RECOVER_AFU CXL_IOWR(0x85, dk_cxlflash_recover_afu)
#define DK_CXLFLASH_MANAGE_LUN CXL_IOWR(0x86, dk_cxlflash_manage_lun)
+#define DK_CXLFLASH_USER_VIRTUAL CXL_IOWR(0x87, dk_cxlflash_uvirtual)
+#define DK_CXLFLASH_VLUN_RESIZE CXL_IOWR(0x88, dk_cxlflash_resize)
+#define DK_CXLFLASH_VLUN_CLONE CXL_IOWR(0x89, dk_cxlflash_clone)
#endif /* ifndef _CXLFLASH_IOCTL_H */