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* [PATCH v5 9/9] Documentation/powerpc: VAS API
From: Haren Myneni @ 2020-04-01 22:08 UTC (permalink / raw)
  To: mpe; +Cc: mikey, herbert, npiggin, linux-crypto, sukadev, linuxppc-dev, dja
In-Reply-To: <1585777592.10664.462.camel@hbabu-laptop>


Power9 introduced Virtual Accelerator Switchboard (VAS) which allows
user space to communicate with Nest Accelerator (NX) directly. But
kernel has to establish channel to NX for user space. This document
describes user space API that application can use to establish
communication channel.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 Documentation/powerpc/index.rst   |   1 +
 Documentation/powerpc/vas-api.rst | 292 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 293 insertions(+)
 create mode 100644 Documentation/powerpc/vas-api.rst

diff --git a/Documentation/powerpc/index.rst b/Documentation/powerpc/index.rst
index 0d45f0f..afe2d5e 100644
--- a/Documentation/powerpc/index.rst
+++ b/Documentation/powerpc/index.rst
@@ -30,6 +30,7 @@ powerpc
     syscall64-abi
     transactional_memory
     ultravisor
+    vas-api
 
 .. only::  subproject and html
 
diff --git a/Documentation/powerpc/vas-api.rst b/Documentation/powerpc/vas-api.rst
new file mode 100644
index 0000000..1217c2f
--- /dev/null
+++ b/Documentation/powerpc/vas-api.rst
@@ -0,0 +1,292 @@
+.. SPDX-License-Identifier: GPL-2.0
+.. _VAS-API:
+
+===================================================
+Virtual Accelerator Switchboard (VAS) userspace API
+===================================================
+
+Introduction
+============
+
+Power9 processor introduced Virtual Accelerator Switchboard (VAS) which
+allows both userspace and kernel communicate to co-processor
+(hardware accelerator) referred to as the Nest Accelerator (NX). The NX
+unit comprises of one or more hardware engines or co-processor types
+such as 842 compression, GZIP compression and encryption. On power9,
+userspace applications will have access to only GZIP Compression engine
+which supports ZLIB and GZIP compression algorithms in the hardware.
+
+To communicate with NX, kernel has to establish a channel or window and
+then requests can be submitted directly without kernel involvement.
+Requests to the GZIP engine must be formatted as a co-processor Request
+Block (CRB) and these CRBs must be submitted to the NX using COPY/PASTE
+instructions to paste the CRB to hardware address that is associated with
+the engine's request queue.
+
+The GZIP engine provides two priority levels of requests: Normal and
+High. Only Normal requests are supported from userspace right now.
+
+This document explains userspace API that is used to interact with
+kernel to setup channel / window which can be used to send compression
+requests directly to NX accelerator.
+
+
+Overview
+========
+
+Application access to the GZIP engine is provided through
+/dev/crypto/nx-gzip device node implemented by the VAS/NX device driver.
+An application must open the /dev/crypto/nx-gzip device to obtain a file
+descriptor (fd). Then should issue VAS_TX_WIN_OPEN ioctl with this fd to
+establish connection to the engine. It means send window is opened on GZIP
+engine for this process. Once a connection is established, the application
+should use the mmap() system call to map the hardware address of engine's
+request queue into the application's virtual address space.
+
+The application can then submit one or more requests to the the engine by
+using copy/paste instructions and pasting the CRBs to the virtual address
+(aka paste_address) returned by mmap(). User space can close the
+established connection or send window by closing the file descriptior
+(close(fd)) or upon the process exit.
+
+Note that applications can send several requests with the same window or
+can establish multiple windows, but one window for each file descriptor.
+
+Following sections provide additional details and references about the
+individual steps.
+
+NX-GZIP Device Node
+===================
+
+There is one /dev/crypto/nx-gzip node in the system and it provides
+access to all GZIP engines in the system. The only valid operations on
+/dev/crypto/nx-gzip are:
+
+	* open() the device for read and write.
+	* issue VAS_TX_WIN_OPEN ioctl
+	* mmap() the engine's request queue into application's virtual
+	  address space (i.e. get a paste_address for the co-processor
+	  engine).
+	* close the device node.
+
+Other file operations on this device node are undefined.
+
+Note that the copy and paste operations go directly to the hardware and
+do not go through this device. Refer COPY/PASTE document for more
+details.
+
+Although a system may have several instances of the NX co-processor
+engines (typically, one per P9 chip) there is just one
+/dev/crypto/nx-gzip device node in the system. When the nx-gzip device
+node is opened, Kernel opens send window on a suitable instance of NX
+accelerator. It finds CPU on which the user process is executing and
+determine the NX instance for the corresponding chip on which this CPU
+belongs.
+
+Applications may chose a specific instance of the NX co-processor using
+the vas_id field in the VAS_TX_WIN_OPEN ioctl as detailed below.
+
+A userspace library libnxz is available here but still in development:
+	 https://github.com/abalib/power-gzip
+
+Applications that use inflate / deflate calls can link with libnxz
+instead of libz and use NX GZIP compression without any modification.
+
+Open /dev/crypto/nx-gzip
+========================
+
+The nx-gzip device should be opened for read and write. No special
+privileges are needed to open the device. Each window corresponds to one
+file descriptor. So if the userspace process needs multiple windows,
+several open calls have to be issued.
+
+See open(2) system call man pages for other details such as return values,
+error codes and restrictions.
+
+VAS_TX_WIN_OPEN ioctl
+=====================
+
+Applications should use the VAS_TX_WIN_OPEN ioctl as follows to establish
+a connection with NX co-processor engine:
+
+	::
+		struct vas_tx_win_open_attr {
+			__u32   version;
+			__s16   vas_id; /* specific instance of vas or -1
+						for default */
+			__u16   reserved1;
+			__u64   flags;	/* For future use */
+			__u64   reserved2[6];
+		};
+
+	version: The version field must be currently set to 1.
+	vas_id: If '-1' is passed, kernel will make a best-effort attempt
+		to assign an optimal instance of NX for the process. To
+		select the specific VAS instance, refer
+		"Discovery of available VAS engines" section below.
+
+	flags, reserved1 and reserved2[6] fields are for future extension
+	and must be set to 0.
+
+	The attributes attr for the VAS_TX_WIN_OPEN ioctl are defined as
+	follows:
+		#define VAS_MAGIC 'v'
+		#define VAS_TX_WIN_OPEN _IOW(VAS_MAGIC, 1,
+						struct vas_tx_win_open_attr)
+
+		struct vas_tx_win_open_attr attr;
+		rc = ioctl(fd, VAS_TX_WIN_OPEN, &attr);
+
+	The VAS_TX_WIN_OPEN ioctl returns 0 on success. On errors, it
+	returns -1 and sets the errno variable to indicate the error.
+
+	Error conditions:
+		EINVAL	fd does not refer to a valid VAS device.
+		EINVAL	Invalid vas ID
+		EINVAL	version is not set with proper value
+		EEXIST	Window is already opened for the given fd
+		ENOMEM	Memory is not available to allocate window
+		ENOSPC	System has too many active windows (connections)
+			opened
+		EINVAL	reserved fields are not set to 0.
+
+	See the ioctl(2) man page for more details, error codes and
+	restrictions.
+
+mmap() NX-GZIP device
+=====================
+
+The mmap() system call for a NX-GZIP device fd returns a paste_address
+that the application can use to copy/paste its CRB to the hardware engines.
+	::
+
+		paste_addr = mmap(addr, size, prot, flags, fd, offset);
+
+	Only restrictions on mmap for a NX-GZIP device fd are:
+		* size should be PAGE_SIZE
+		* offset parameter should be 0ULL
+
+	Refer to mmap(2) man page for additional details/restrictions.
+	In addition to the error conditions listed on the mmap(2) man
+	page, can also fail with one of the following error codes:
+
+		EINVAL	fd is not associated with an open window
+			(i.e mmap() does not follow a successful call
+			to the VAS_TX_WIN_OPEN ioctl).
+		EINVAL	offset field is not 0ULL.
+
+Discovery of available VAS engines
+==================================
+
+Each available VAS instance in the system will have a device tree node
+like /proc/device-tree/vas@* or /proc/device-tree/xscom@*/vas@*.
+Determine the chip or VAS instance and use the corresponding ibm,vas-id
+property value in this node to select specific VAS instance.
+
+Copy/Paste operations
+=====================
+
+Applications should use the copy and paste instructions to send CRB to NX.
+Refer section 4.4 in PowerISA for Copy/Paste instructions:
+https://openpowerfoundation.org/?resource_lib=power-isa-version-3-0
+
+CRB Specification and use NX
+============================
+
+Applications should format requests to the co-processor using the
+co-processor Request Block (CRBs). Refer NX-GZIP user's manual for the format
+of CRB and use NX from userspace such as sending requests and checking
+request status.
+
+NX Fault handling
+=================
+
+Applications send requests to NX and wait for the status by polling on
+co-processor Status Block (CSB) flags. NX updates status in CSB after each
+request is processed. Refer NX-GZIP user's manual for the format of CSB and
+status flags.
+
+In case if NX encounters translation error (called NX page fault) on CSB
+address or any request buffer, raises an interrupt on the CPU to handle the
+fault. Page fault can happen if an application passes invalid addresses or
+request buffers are not in memory. The operating system handles the fault by
+updating CSB with the following data:
+
+	csb.flags = CSB_V;
+	csb.cc = CSB_CC_TRANSLATION;
+	csb.ce = CSB_CE_TERMINATION;
+	csb.address = fault_address;
+
+When an application receives translation error, it can touch or access
+the page that has a fault address so that this page will be in memory. Then
+the application can resend this request to NX.
+
+If the OS can not update CSB due to invalid CSB address, sends SEGV signal
+to the process who opened the send window on which the original request was
+issued. This signal returns with the following siginfo struct:
+
+	siginfo.si_signo = SIGSEGV;
+	siginfo.si_errno = EFAULT;
+	siginfo.si_code = SEGV_MAPERR;
+	siginfo.si_addr = CSB adress;
+
+In the case of multi-thread applications, NX send windows can be shared
+across all threads. For example, a child thread can open a send window,
+but other threads can send requests to NX using this window. These
+requests will be successful even in the case of OS handling faults as long
+as CSB address is valid. If the NX request contains an invalid CSB address,
+the signal will be sent to the child thread that opened the window. But if
+the thread is exited without closing the window and the request is issued
+using this window. the signal will be issued to the thread group leader
+(tgid). It is up to the application whether to ignore or handle these
+signals.
+
+NX-GZIP User's Manual:
+https://github.com/libnxz/power-gzip/blob/master/power_nx_gzip_um.pdf
+
+Simple example
+==============
+
+	::
+		int use_nx_gzip()
+		{
+			int rc, fd;
+			void *addr;
+			struct vas_setup_attr txattr;
+
+			fd = open("/dev/crypto/nx-gzip", O_RDWR);
+			if (fd < 0) {
+				fprintf(stderr, "open nx-gzip failed\n");
+				return -1;
+			}
+			memset(&txattr, 0, sizeof(txattr));
+			txattr.version = 1;
+			txattr.vas_id = -1
+			rc = ioctl(fd, VAS_TX_WIN_OPEN,
+					(unsigned long)&txattr);
+			if (rc < 0) {
+				fprintf(stderr, "ioctl() n %d, error %d\n",
+						rc, errno);
+				return rc;
+			}
+			addr = mmap(NULL, 4096, PROT_READ|PROT_WRITE,
+					MAP_SHARED, fd, 0ULL);
+			if (addr == MAP_FAILED) {
+				fprintf(stderr, "mmap() failed, errno %d\n",
+						errno);
+				return -errno;
+			}
+			do {
+				//Format CRB request with compression or
+				//uncompression
+				// Refer tests for vas_copy/vas_paste
+				vas_copy((&crb, 0, 1);
+				vas_paste(addr, 0, 1);
+				// Poll on csb.flags with timeout
+				// csb address is listed in CRB
+			} while (true)
+			close(fd) or window can be closed upon process exit
+		}
+
+	Refer https://github.com/abalib/power-gzip for tests or more
+	use cases.
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v5 8/9] crypto/nx: Remove 'pid' in vas_tx_win_attr struct
From: Haren Myneni @ 2020-04-01 22:08 UTC (permalink / raw)
  To: mpe; +Cc: mikey, herbert, npiggin, linux-crypto, sukadev, linuxppc-dev, dja
In-Reply-To: <1585777592.10664.462.camel@hbabu-laptop>


When window is opened, pid reference is taken for user space
windows. Not needed for kernel windows. So remove 'pid' in
vas_tx_win_attr struct.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 arch/powerpc/include/asm/vas.h        | 1 -
 drivers/crypto/nx/nx-common-powernv.c | 1 -
 2 files changed, 2 deletions(-)

diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
index e064953..994db6f 100644
--- a/arch/powerpc/include/asm/vas.h
+++ b/arch/powerpc/include/asm/vas.h
@@ -86,7 +86,6 @@ struct vas_tx_win_attr {
 	int wcreds_max;
 	int lpid;
 	int pidr;		/* hardware PID (from SPRN_PID) */
-	int pid;		/* linux process id */
 	int pswid;
 	int rsvd_txbuf_count;
 	int tc_mode;
diff --git a/drivers/crypto/nx/nx-common-powernv.c b/drivers/crypto/nx/nx-common-powernv.c
index f570691..38333e4 100644
--- a/drivers/crypto/nx/nx-common-powernv.c
+++ b/drivers/crypto/nx/nx-common-powernv.c
@@ -692,7 +692,6 @@ static struct vas_window *nx_alloc_txwin(struct nx_coproc *coproc)
 	 */
 	vas_init_tx_win_attr(&txattr, coproc->ct);
 	txattr.lpid = 0;	/* lpid is 0 for kernel requests */
-	txattr.pid = 0;		/* pid is 0 for kernel requests */
 
 	/*
 	 * Open a VAS send window which is used to send request to NX.
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v5 7/9] crypto/nx: Enable and setup GZIP compression type
From: Haren Myneni @ 2020-04-01 22:07 UTC (permalink / raw)
  To: mpe; +Cc: mikey, herbert, npiggin, linux-crypto, sukadev, linuxppc-dev, dja
In-Reply-To: <1585777592.10664.462.camel@hbabu-laptop>


Changes to probe GZIP device-tree nodes, open RX windows and setup
GZIP compression type. No plans to provide GZIP usage in kernel right
now, but this patch enables GZIP for user space usage.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 drivers/crypto/nx/nx-common-powernv.c | 43 ++++++++++++++++++++++++++++++-----
 1 file changed, 37 insertions(+), 6 deletions(-)

diff --git a/drivers/crypto/nx/nx-common-powernv.c b/drivers/crypto/nx/nx-common-powernv.c
index 82dfa60..f570691 100644
--- a/drivers/crypto/nx/nx-common-powernv.c
+++ b/drivers/crypto/nx/nx-common-powernv.c
@@ -65,6 +65,7 @@ struct nx_coproc {
  * Using same values as in skiboot or coprocessor type representing
  * in NX workbook.
  */
+#define NX_CT_GZIP	(2)	/* on P9 and later */
 #define NX_CT_842	(3)
 
 static int (*nx842_powernv_exec)(const unsigned char *in,
@@ -819,6 +820,9 @@ static int __init vas_cfg_coproc_info(struct device_node *dn, int chip_id,
 	if (type == NX_CT_842)
 		ret = nx_set_ct(coproc, priority, VAS_COP_TYPE_842_HIPRI,
 			VAS_COP_TYPE_842);
+	else if (type == NX_CT_GZIP)
+		ret = nx_set_ct(coproc, priority, VAS_COP_TYPE_GZIP_HIPRI,
+				VAS_COP_TYPE_GZIP);
 
 	if (ret)
 		goto err_out;
@@ -867,12 +871,16 @@ static int __init vas_cfg_coproc_info(struct device_node *dn, int chip_id,
 	return ret;
 }
 
-static int __init nx_coproc_init(int chip_id, int ct_842)
+static int __init nx_coproc_init(int chip_id, int ct_842, int ct_gzip)
 {
 	int ret = 0;
 
 	if (opal_check_token(OPAL_NX_COPROC_INIT)) {
 		ret = opal_nx_coproc_init(chip_id, ct_842);
+
+		if (!ret)
+			ret = opal_nx_coproc_init(chip_id, ct_gzip);
+
 		if (ret) {
 			ret = opal_error_code(ret);
 			pr_err("Failed to initialize NX for chip(%d): %d\n",
@@ -902,8 +910,8 @@ static int __init find_nx_device_tree(struct device_node *dn, int chip_id,
 static int __init nx_powernv_probe_vas(struct device_node *pn)
 {
 	int chip_id, vasid, ret = 0;
+	int ct_842 = 0, ct_gzip = 0;
 	struct device_node *dn;
-	int ct_842 = 0;
 
 	chip_id = of_get_ibm_chip_id(pn);
 	if (chip_id < 0) {
@@ -920,19 +928,24 @@ static int __init nx_powernv_probe_vas(struct device_node *pn)
 	for_each_child_of_node(pn, dn) {
 		ret = find_nx_device_tree(dn, chip_id, vasid, NX_CT_842,
 					"ibm,p9-nx-842", &ct_842);
+
+		if (!ret)
+			ret = find_nx_device_tree(dn, chip_id, vasid,
+				NX_CT_GZIP, "ibm,p9-nx-gzip", &ct_gzip);
+
 		if (ret)
 			return ret;
 	}
 
-	if (!ct_842) {
-		pr_err("NX842 FIFO nodes are missing\n");
+	if (!ct_842 || !ct_gzip) {
+		pr_err("NX FIFO nodes are missing\n");
 		return -EINVAL;
 	}
 
 	/*
 	 * Initialize NX instance for both high and normal priority FIFOs.
 	 */
-	ret = nx_coproc_init(chip_id, ct_842);
+	ret = nx_coproc_init(chip_id, ct_842, ct_gzip);
 
 	return ret;
 }
@@ -1072,10 +1085,19 @@ static __init int nx_compress_powernv_init(void)
 		nx842_powernv_exec = nx842_exec_icswx;
 	} else {
 		/*
+		 * Register VAS user space API for NX GZIP so
+		 * that user space can use GZIP engine.
+		 * 842 compression is supported only in kernel.
+		 */
+		ret = vas_register_coproc_api(THIS_MODULE);
+
+		/*
 		 * GZIP is not supported in kernel right now.
 		 * So open tx windows only for 842.
 		 */
-		ret = nx_open_percpu_txwins();
+		if (!ret)
+			ret = nx_open_percpu_txwins();
+
 		if (ret) {
 			nx_delete_coprocs();
 			return ret;
@@ -1096,6 +1118,15 @@ static __init int nx_compress_powernv_init(void)
 
 static void __exit nx_compress_powernv_exit(void)
 {
+	/*
+	 * GZIP engine is supported only in power9 or later and nx842_ct
+	 * is used on power8 (icswx).
+	 * VAS API for NX GZIP is registered during init for user space
+	 * use. So delete this API use for GZIP engine.
+	 */
+	if (!nx842_ct)
+		vas_unregister_coproc_api();
+
 	crypto_unregister_alg(&nx842_powernv_alg);
 
 	nx_delete_coprocs();
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH 6/9] crypto/nx: Make enable code generic to add new GZIP compression type
From: Haren Myneni @ 2020-04-01 22:06 UTC (permalink / raw)
  To: mpe; +Cc: mikey, herbert, npiggin, linux-crypto, sukadev, linuxppc-dev, dja
In-Reply-To: <1585777592.10664.462.camel@hbabu-laptop>


Make setup and enable code generic to support new GZIP compression type.
Changed nx842 reference to nx and moved some code to new functions.
Functionality is not changed except sparse warning fix - setting NULL
instead of 0 for per_cpu send window in nx_delete_coprocs().

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 drivers/crypto/nx/nx-common-powernv.c | 161 +++++++++++++++++++++-------------
 1 file changed, 101 insertions(+), 60 deletions(-)

diff --git a/drivers/crypto/nx/nx-common-powernv.c b/drivers/crypto/nx/nx-common-powernv.c
index f42881f..82dfa60 100644
--- a/drivers/crypto/nx/nx-common-powernv.c
+++ b/drivers/crypto/nx/nx-common-powernv.c
@@ -40,9 +40,9 @@ struct nx842_workmem {
 	char padding[WORKMEM_ALIGN]; /* unused, to allow alignment */
 } __packed __aligned(WORKMEM_ALIGN);
 
-struct nx842_coproc {
+struct nx_coproc {
 	unsigned int chip_id;
-	unsigned int ct;
+	unsigned int ct;	/* Can be 842 or GZIP high/normal*/
 	unsigned int ci;	/* Coprocessor instance, used with icswx */
 	struct {
 		struct vas_window *rxwin;
@@ -58,9 +58,15 @@ struct nx842_coproc {
 static DEFINE_PER_CPU(struct vas_window *, cpu_txwin);
 
 /* no cpu hotplug on powernv, so this list never changes after init */
-static LIST_HEAD(nx842_coprocs);
+static LIST_HEAD(nx_coprocs);
 static unsigned int nx842_ct;	/* used in icswx function */
 
+/*
+ * Using same values as in skiboot or coprocessor type representing
+ * in NX workbook.
+ */
+#define NX_CT_842	(3)
+
 static int (*nx842_powernv_exec)(const unsigned char *in,
 				unsigned int inlen, unsigned char *out,
 				unsigned int *outlenp, void *workmem, int fc);
@@ -666,15 +672,15 @@ static int nx842_powernv_decompress(const unsigned char *in, unsigned int inlen,
 				      wmem, CCW_FC_842_DECOMP_CRC);
 }
 
-static inline void nx842_add_coprocs_list(struct nx842_coproc *coproc,
+static inline void nx_add_coprocs_list(struct nx_coproc *coproc,
 					int chipid)
 {
 	coproc->chip_id = chipid;
 	INIT_LIST_HEAD(&coproc->list);
-	list_add(&coproc->list, &nx842_coprocs);
+	list_add(&coproc->list, &nx_coprocs);
 }
 
-static struct vas_window *nx842_alloc_txwin(struct nx842_coproc *coproc)
+static struct vas_window *nx_alloc_txwin(struct nx_coproc *coproc)
 {
 	struct vas_window *txwin = NULL;
 	struct vas_tx_win_attr txattr;
@@ -704,9 +710,9 @@ static struct vas_window *nx842_alloc_txwin(struct nx842_coproc *coproc)
  * cpu_txwin is used in copy/paste operation for each compression /
  * decompression request.
  */
-static int nx842_open_percpu_txwins(void)
+static int nx_open_percpu_txwins(void)
 {
-	struct nx842_coproc *coproc, *n;
+	struct nx_coproc *coproc, *n;
 	unsigned int i, chip_id;
 
 	for_each_possible_cpu(i) {
@@ -714,17 +720,18 @@ static int nx842_open_percpu_txwins(void)
 
 		chip_id = cpu_to_chip_id(i);
 
-		list_for_each_entry_safe(coproc, n, &nx842_coprocs, list) {
+		list_for_each_entry_safe(coproc, n, &nx_coprocs, list) {
 			/*
 			 * Kernel requests use only high priority FIFOs. So
 			 * open send windows for these FIFOs.
+			 * GZIP is not supported in kernel right now.
 			 */
 
 			if (coproc->ct != VAS_COP_TYPE_842_HIPRI)
 				continue;
 
 			if (coproc->chip_id == chip_id) {
-				txwin = nx842_alloc_txwin(coproc);
+				txwin = nx_alloc_txwin(coproc);
 				if (IS_ERR(txwin))
 					return PTR_ERR(txwin);
 
@@ -743,13 +750,28 @@ static int nx842_open_percpu_txwins(void)
 	return 0;
 }
 
+static int __init nx_set_ct(struct nx_coproc *coproc, const char *priority,
+				int high, int normal)
+{
+	if (!strcmp(priority, "High"))
+		coproc->ct = high;
+	else if (!strcmp(priority, "Normal"))
+		coproc->ct = normal;
+	else {
+		pr_err("Invalid RxFIFO priority value\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int __init vas_cfg_coproc_info(struct device_node *dn, int chip_id,
-					int vasid, int *ct)
+					int vasid, int type, int *ct)
 {
 	struct vas_window *rxwin = NULL;
 	struct vas_rx_win_attr rxattr;
-	struct nx842_coproc *coproc;
 	u32 lpid, pid, tid, fifo_size;
+	struct nx_coproc *coproc;
 	u64 rx_fifo;
 	const char *priority;
 	int ret;
@@ -794,15 +816,12 @@ static int __init vas_cfg_coproc_info(struct device_node *dn, int chip_id,
 	if (!coproc)
 		return -ENOMEM;
 
-	if (!strcmp(priority, "High"))
-		coproc->ct = VAS_COP_TYPE_842_HIPRI;
-	else if (!strcmp(priority, "Normal"))
-		coproc->ct = VAS_COP_TYPE_842;
-	else {
-		pr_err("Invalid RxFIFO priority value\n");
-		ret =  -EINVAL;
+	if (type == NX_CT_842)
+		ret = nx_set_ct(coproc, priority, VAS_COP_TYPE_842_HIPRI,
+			VAS_COP_TYPE_842);
+
+	if (ret)
 		goto err_out;
-	}
 
 	vas_init_rx_win_attr(&rxattr, coproc->ct);
 	rxattr.rx_fifo = (void *)rx_fifo;
@@ -830,7 +849,7 @@ static int __init vas_cfg_coproc_info(struct device_node *dn, int chip_id,
 
 	coproc->vas.rxwin = rxwin;
 	coproc->vas.id = vasid;
-	nx842_add_coprocs_list(coproc, chip_id);
+	nx_add_coprocs_list(coproc, chip_id);
 
 	/*
 	 * (lpid, pid, tid) combination has to be unique for each
@@ -848,13 +867,43 @@ static int __init vas_cfg_coproc_info(struct device_node *dn, int chip_id,
 	return ret;
 }
 
+static int __init nx_coproc_init(int chip_id, int ct_842)
+{
+	int ret = 0;
 
-static int __init nx842_powernv_probe_vas(struct device_node *pn)
+	if (opal_check_token(OPAL_NX_COPROC_INIT)) {
+		ret = opal_nx_coproc_init(chip_id, ct_842);
+		if (ret) {
+			ret = opal_error_code(ret);
+			pr_err("Failed to initialize NX for chip(%d): %d\n",
+				chip_id, ret);
+		}
+	} else
+		pr_warn("Firmware doesn't support NX initialization\n");
+
+	return ret;
+}
+
+static int __init find_nx_device_tree(struct device_node *dn, int chip_id,
+					int vasid, int type, char *devname,
+					int *ct)
+{
+	int ret = 0;
+
+	if (of_device_is_compatible(dn, devname)) {
+		ret  = vas_cfg_coproc_info(dn, chip_id, vasid, type, ct);
+		if (ret)
+			of_node_put(dn);
+	}
+
+	return ret;
+}
+
+static int __init nx_powernv_probe_vas(struct device_node *pn)
 {
-	struct device_node *dn;
 	int chip_id, vasid, ret = 0;
-	int nx_fifo_found = 0;
-	int uninitialized_var(ct);
+	struct device_node *dn;
+	int ct_842 = 0;
 
 	chip_id = of_get_ibm_chip_id(pn);
 	if (chip_id < 0) {
@@ -869,17 +918,13 @@ static int __init nx842_powernv_probe_vas(struct device_node *pn)
 	}
 
 	for_each_child_of_node(pn, dn) {
-		if (of_device_is_compatible(dn, "ibm,p9-nx-842")) {
-			ret = vas_cfg_coproc_info(dn, chip_id, vasid, &ct);
-			if (ret) {
-				of_node_put(dn);
-				return ret;
-			}
-			nx_fifo_found++;
-		}
+		ret = find_nx_device_tree(dn, chip_id, vasid, NX_CT_842,
+					"ibm,p9-nx-842", &ct_842);
+		if (ret)
+			return ret;
 	}
 
-	if (!nx_fifo_found) {
+	if (!ct_842) {
 		pr_err("NX842 FIFO nodes are missing\n");
 		return -EINVAL;
 	}
@@ -887,22 +932,14 @@ static int __init nx842_powernv_probe_vas(struct device_node *pn)
 	/*
 	 * Initialize NX instance for both high and normal priority FIFOs.
 	 */
-	if (opal_check_token(OPAL_NX_COPROC_INIT)) {
-		ret = opal_nx_coproc_init(chip_id, ct);
-		if (ret) {
-			pr_err("Failed to initialize NX for chip(%d): %d\n",
-				chip_id, ret);
-			ret = opal_error_code(ret);
-		}
-	} else
-		pr_warn("Firmware doesn't support NX initialization\n");
+	ret = nx_coproc_init(chip_id, ct_842);
 
 	return ret;
 }
 
 static int __init nx842_powernv_probe(struct device_node *dn)
 {
-	struct nx842_coproc *coproc;
+	struct nx_coproc *coproc;
 	unsigned int ct, ci;
 	int chip_id;
 
@@ -928,7 +965,7 @@ static int __init nx842_powernv_probe(struct device_node *dn)
 
 	coproc->ct = ct;
 	coproc->ci = ci;
-	nx842_add_coprocs_list(coproc, chip_id);
+	nx_add_coprocs_list(coproc, chip_id);
 
 	pr_info("coprocessor found on chip %d, CT %d CI %d\n", chip_id, ct, ci);
 
@@ -941,9 +978,9 @@ static int __init nx842_powernv_probe(struct device_node *dn)
 	return 0;
 }
 
-static void nx842_delete_coprocs(void)
+static void nx_delete_coprocs(void)
 {
-	struct nx842_coproc *coproc, *n;
+	struct nx_coproc *coproc, *n;
 	struct vas_window *txwin;
 	int i;
 
@@ -955,10 +992,10 @@ static void nx842_delete_coprocs(void)
 		if (txwin)
 			vas_win_close(txwin);
 
-		per_cpu(cpu_txwin, i) = 0;
+		per_cpu(cpu_txwin, i) = NULL;
 	}
 
-	list_for_each_entry_safe(coproc, n, &nx842_coprocs, list) {
+	list_for_each_entry_safe(coproc, n, &nx_coprocs, list) {
 		if (coproc->vas.rxwin)
 			vas_win_close(coproc->vas.rxwin);
 
@@ -1002,7 +1039,7 @@ static int nx842_powernv_crypto_init(struct crypto_tfm *tfm)
 	.coa_decompress		= nx842_crypto_decompress } }
 };
 
-static __init int nx842_powernv_init(void)
+static __init int nx_compress_powernv_init(void)
 {
 	struct device_node *dn;
 	int ret;
@@ -1017,15 +1054,15 @@ static __init int nx842_powernv_init(void)
 	BUILD_BUG_ON(DDE_BUFFER_SIZE_MULT % DDE_BUFFER_LAST_MULT);
 
 	for_each_compatible_node(dn, NULL, "ibm,power9-nx") {
-		ret = nx842_powernv_probe_vas(dn);
+		ret = nx_powernv_probe_vas(dn);
 		if (ret) {
-			nx842_delete_coprocs();
+			nx_delete_coprocs();
 			of_node_put(dn);
 			return ret;
 		}
 	}
 
-	if (list_empty(&nx842_coprocs)) {
+	if (list_empty(&nx_coprocs)) {
 		for_each_compatible_node(dn, NULL, "ibm,power-nx")
 			nx842_powernv_probe(dn);
 
@@ -1034,9 +1071,13 @@ static __init int nx842_powernv_init(void)
 
 		nx842_powernv_exec = nx842_exec_icswx;
 	} else {
-		ret = nx842_open_percpu_txwins();
+		/*
+		 * GZIP is not supported in kernel right now.
+		 * So open tx windows only for 842.
+		 */
+		ret = nx_open_percpu_txwins();
 		if (ret) {
-			nx842_delete_coprocs();
+			nx_delete_coprocs();
 			return ret;
 		}
 
@@ -1045,18 +1086,18 @@ static __init int nx842_powernv_init(void)
 
 	ret = crypto_register_alg(&nx842_powernv_alg);
 	if (ret) {
-		nx842_delete_coprocs();
+		nx_delete_coprocs();
 		return ret;
 	}
 
 	return 0;
 }
-module_init(nx842_powernv_init);
+module_init(nx_compress_powernv_init);
 
-static void __exit nx842_powernv_exit(void)
+static void __exit nx_compress_powernv_exit(void)
 {
 	crypto_unregister_alg(&nx842_powernv_alg);
 
-	nx842_delete_coprocs();
+	nx_delete_coprocs();
 }
-module_exit(nx842_powernv_exit);
+module_exit(nx_compress_powernv_exit);
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v5 5/9] crypto/nx: Rename nx-842-powernv file name to nx-common-powernv
From: Haren Myneni @ 2020-04-01 22:05 UTC (permalink / raw)
  To: mpe; +Cc: mikey, herbert, npiggin, linux-crypto, sukadev, linuxppc-dev, dja
In-Reply-To: <1585777592.10664.462.camel@hbabu-laptop>


Rename nx-842-powernv.c to nx-common-powernv.c to add code for setup
and enable new GZIP compression type. The actual functionality is not
changed in this patch.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 drivers/crypto/nx/Makefile            |    2 +-
 drivers/crypto/nx/nx-842-powernv.c    | 1062 ---------------------------------
 drivers/crypto/nx/nx-common-powernv.c | 1062 +++++++++++++++++++++++++++++++++
 3 files changed, 1063 insertions(+), 1063 deletions(-)
 delete mode 100644 drivers/crypto/nx/nx-842-powernv.c
 create mode 100644 drivers/crypto/nx/nx-common-powernv.c

diff --git a/drivers/crypto/nx/Makefile b/drivers/crypto/nx/Makefile
index 015155d..bc89a20 100644
--- a/drivers/crypto/nx/Makefile
+++ b/drivers/crypto/nx/Makefile
@@ -15,4 +15,4 @@ obj-$(CONFIG_CRYPTO_DEV_NX_COMPRESS_PSERIES) += nx-compress-pseries.o nx-compres
 obj-$(CONFIG_CRYPTO_DEV_NX_COMPRESS_POWERNV) += nx-compress-powernv.o nx-compress.o
 nx-compress-objs := nx-842.o
 nx-compress-pseries-objs := nx-842-pseries.o
-nx-compress-powernv-objs := nx-842-powernv.o
+nx-compress-powernv-objs := nx-common-powernv.o
diff --git a/drivers/crypto/nx/nx-842-powernv.c b/drivers/crypto/nx/nx-842-powernv.c
deleted file mode 100644
index 8e63326..0000000
--- a/drivers/crypto/nx/nx-842-powernv.c
+++ /dev/null
@@ -1,1062 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Driver for IBM PowerNV 842 compression accelerator
- *
- * Copyright (C) 2015 Dan Streetman, IBM Corp
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include "nx-842.h"
-
-#include <linux/timer.h>
-
-#include <asm/prom.h>
-#include <asm/icswx.h>
-#include <asm/vas.h>
-#include <asm/reg.h>
-#include <asm/opal-api.h>
-#include <asm/opal.h>
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");
-MODULE_DESCRIPTION("842 H/W Compression driver for IBM PowerNV processors");
-MODULE_ALIAS_CRYPTO("842");
-MODULE_ALIAS_CRYPTO("842-nx");
-
-#define WORKMEM_ALIGN	(CRB_ALIGN)
-#define CSB_WAIT_MAX	(5000) /* ms */
-#define VAS_RETRIES	(10)
-
-struct nx842_workmem {
-	/* Below fields must be properly aligned */
-	struct coprocessor_request_block crb; /* CRB_ALIGN align */
-	struct data_descriptor_entry ddl_in[DDL_LEN_MAX]; /* DDE_ALIGN align */
-	struct data_descriptor_entry ddl_out[DDL_LEN_MAX]; /* DDE_ALIGN align */
-	/* Above fields must be properly aligned */
-
-	ktime_t start;
-
-	char padding[WORKMEM_ALIGN]; /* unused, to allow alignment */
-} __packed __aligned(WORKMEM_ALIGN);
-
-struct nx842_coproc {
-	unsigned int chip_id;
-	unsigned int ct;
-	unsigned int ci;	/* Coprocessor instance, used with icswx */
-	struct {
-		struct vas_window *rxwin;
-		int id;
-	} vas;
-	struct list_head list;
-};
-
-/*
- * Send the request to NX engine on the chip for the corresponding CPU
- * where the process is executing. Use with VAS function.
- */
-static DEFINE_PER_CPU(struct vas_window *, cpu_txwin);
-
-/* no cpu hotplug on powernv, so this list never changes after init */
-static LIST_HEAD(nx842_coprocs);
-static unsigned int nx842_ct;	/* used in icswx function */
-
-static int (*nx842_powernv_exec)(const unsigned char *in,
-				unsigned int inlen, unsigned char *out,
-				unsigned int *outlenp, void *workmem, int fc);
-
-/**
- * setup_indirect_dde - Setup an indirect DDE
- *
- * The DDE is setup with the the DDE count, byte count, and address of
- * first direct DDE in the list.
- */
-static void setup_indirect_dde(struct data_descriptor_entry *dde,
-			       struct data_descriptor_entry *ddl,
-			       unsigned int dde_count, unsigned int byte_count)
-{
-	dde->flags = 0;
-	dde->count = dde_count;
-	dde->index = 0;
-	dde->length = cpu_to_be32(byte_count);
-	dde->address = cpu_to_be64(nx842_get_pa(ddl));
-}
-
-/**
- * setup_direct_dde - Setup single DDE from buffer
- *
- * The DDE is setup with the buffer and length.  The buffer must be properly
- * aligned.  The used length is returned.
- * Returns:
- *   N    Successfully set up DDE with N bytes
- */
-static unsigned int setup_direct_dde(struct data_descriptor_entry *dde,
-				     unsigned long pa, unsigned int len)
-{
-	unsigned int l = min_t(unsigned int, len, LEN_ON_PAGE(pa));
-
-	dde->flags = 0;
-	dde->count = 0;
-	dde->index = 0;
-	dde->length = cpu_to_be32(l);
-	dde->address = cpu_to_be64(pa);
-
-	return l;
-}
-
-/**
- * setup_ddl - Setup DDL from buffer
- *
- * Returns:
- *   0		Successfully set up DDL
- */
-static int setup_ddl(struct data_descriptor_entry *dde,
-		     struct data_descriptor_entry *ddl,
-		     unsigned char *buf, unsigned int len,
-		     bool in)
-{
-	unsigned long pa = nx842_get_pa(buf);
-	int i, ret, total_len = len;
-
-	if (!IS_ALIGNED(pa, DDE_BUFFER_ALIGN)) {
-		pr_debug("%s buffer pa 0x%lx not 0x%x-byte aligned\n",
-			 in ? "input" : "output", pa, DDE_BUFFER_ALIGN);
-		return -EINVAL;
-	}
-
-	/* only need to check last mult; since buffer must be
-	 * DDE_BUFFER_ALIGN aligned, and that is a multiple of
-	 * DDE_BUFFER_SIZE_MULT, and pre-last page DDE buffers
-	 * are guaranteed a multiple of DDE_BUFFER_SIZE_MULT.
-	 */
-	if (len % DDE_BUFFER_LAST_MULT) {
-		pr_debug("%s buffer len 0x%x not a multiple of 0x%x\n",
-			 in ? "input" : "output", len, DDE_BUFFER_LAST_MULT);
-		if (in)
-			return -EINVAL;
-		len = round_down(len, DDE_BUFFER_LAST_MULT);
-	}
-
-	/* use a single direct DDE */
-	if (len <= LEN_ON_PAGE(pa)) {
-		ret = setup_direct_dde(dde, pa, len);
-		WARN_ON(ret < len);
-		return 0;
-	}
-
-	/* use the DDL */
-	for (i = 0; i < DDL_LEN_MAX && len > 0; i++) {
-		ret = setup_direct_dde(&ddl[i], pa, len);
-		buf += ret;
-		len -= ret;
-		pa = nx842_get_pa(buf);
-	}
-
-	if (len > 0) {
-		pr_debug("0x%x total %s bytes 0x%x too many for DDL.\n",
-			 total_len, in ? "input" : "output", len);
-		if (in)
-			return -EMSGSIZE;
-		total_len -= len;
-	}
-	setup_indirect_dde(dde, ddl, i, total_len);
-
-	return 0;
-}
-
-#define CSB_ERR(csb, msg, ...)					\
-	pr_err("ERROR: " msg " : %02x %02x %02x %02x %08x\n",	\
-	       ##__VA_ARGS__, (csb)->flags,			\
-	       (csb)->cs, (csb)->cc, (csb)->ce,			\
-	       be32_to_cpu((csb)->count))
-
-#define CSB_ERR_ADDR(csb, msg, ...)				\
-	CSB_ERR(csb, msg " at %lx", ##__VA_ARGS__,		\
-		(unsigned long)be64_to_cpu((csb)->address))
-
-/**
- * wait_for_csb
- */
-static int wait_for_csb(struct nx842_workmem *wmem,
-			struct coprocessor_status_block *csb)
-{
-	ktime_t start = wmem->start, now = ktime_get();
-	ktime_t timeout = ktime_add_ms(start, CSB_WAIT_MAX);
-
-	while (!(READ_ONCE(csb->flags) & CSB_V)) {
-		cpu_relax();
-		now = ktime_get();
-		if (ktime_after(now, timeout))
-			break;
-	}
-
-	/* hw has updated csb and output buffer */
-	barrier();
-
-	/* check CSB flags */
-	if (!(csb->flags & CSB_V)) {
-		CSB_ERR(csb, "CSB still not valid after %ld us, giving up",
-			(long)ktime_us_delta(now, start));
-		return -ETIMEDOUT;
-	}
-	if (csb->flags & CSB_F) {
-		CSB_ERR(csb, "Invalid CSB format");
-		return -EPROTO;
-	}
-	if (csb->flags & CSB_CH) {
-		CSB_ERR(csb, "Invalid CSB chaining state");
-		return -EPROTO;
-	}
-
-	/* verify CSB completion sequence is 0 */
-	if (csb->cs) {
-		CSB_ERR(csb, "Invalid CSB completion sequence");
-		return -EPROTO;
-	}
-
-	/* check CSB Completion Code */
-	switch (csb->cc) {
-	/* no error */
-	case CSB_CC_SUCCESS:
-		break;
-	case CSB_CC_TPBC_GT_SPBC:
-		/* not an error, but the compressed data is
-		 * larger than the uncompressed data :(
-		 */
-		break;
-
-	/* input data errors */
-	case CSB_CC_OPERAND_OVERLAP:
-		/* input and output buffers overlap */
-		CSB_ERR(csb, "Operand Overlap error");
-		return -EINVAL;
-	case CSB_CC_INVALID_OPERAND:
-		CSB_ERR(csb, "Invalid operand");
-		return -EINVAL;
-	case CSB_CC_NOSPC:
-		/* output buffer too small */
-		return -ENOSPC;
-	case CSB_CC_ABORT:
-		CSB_ERR(csb, "Function aborted");
-		return -EINTR;
-	case CSB_CC_CRC_MISMATCH:
-		CSB_ERR(csb, "CRC mismatch");
-		return -EINVAL;
-	case CSB_CC_TEMPL_INVALID:
-		CSB_ERR(csb, "Compressed data template invalid");
-		return -EINVAL;
-	case CSB_CC_TEMPL_OVERFLOW:
-		CSB_ERR(csb, "Compressed data template shows data past end");
-		return -EINVAL;
-	case CSB_CC_EXCEED_BYTE_COUNT:	/* P9 or later */
-		/*
-		 * DDE byte count exceeds the limit specified in Maximum
-		 * byte count register.
-		 */
-		CSB_ERR(csb, "DDE byte count exceeds the limit");
-		return -EINVAL;
-
-	/* these should not happen */
-	case CSB_CC_INVALID_ALIGN:
-		/* setup_ddl should have detected this */
-		CSB_ERR_ADDR(csb, "Invalid alignment");
-		return -EINVAL;
-	case CSB_CC_DATA_LENGTH:
-		/* setup_ddl should have detected this */
-		CSB_ERR(csb, "Invalid data length");
-		return -EINVAL;
-	case CSB_CC_WR_TRANSLATION:
-	case CSB_CC_TRANSLATION:
-	case CSB_CC_TRANSLATION_DUP1:
-	case CSB_CC_TRANSLATION_DUP2:
-	case CSB_CC_TRANSLATION_DUP3:
-	case CSB_CC_TRANSLATION_DUP4:
-	case CSB_CC_TRANSLATION_DUP5:
-	case CSB_CC_TRANSLATION_DUP6:
-		/* should not happen, we use physical addrs */
-		CSB_ERR_ADDR(csb, "Translation error");
-		return -EPROTO;
-	case CSB_CC_WR_PROTECTION:
-	case CSB_CC_PROTECTION:
-	case CSB_CC_PROTECTION_DUP1:
-	case CSB_CC_PROTECTION_DUP2:
-	case CSB_CC_PROTECTION_DUP3:
-	case CSB_CC_PROTECTION_DUP4:
-	case CSB_CC_PROTECTION_DUP5:
-	case CSB_CC_PROTECTION_DUP6:
-		/* should not happen, we use physical addrs */
-		CSB_ERR_ADDR(csb, "Protection error");
-		return -EPROTO;
-	case CSB_CC_PRIVILEGE:
-		/* shouldn't happen, we're in HYP mode */
-		CSB_ERR(csb, "Insufficient Privilege error");
-		return -EPROTO;
-	case CSB_CC_EXCESSIVE_DDE:
-		/* shouldn't happen, setup_ddl doesn't use many dde's */
-		CSB_ERR(csb, "Too many DDEs in DDL");
-		return -EINVAL;
-	case CSB_CC_TRANSPORT:
-	case CSB_CC_INVALID_CRB:	/* P9 or later */
-		/* shouldn't happen, we setup CRB correctly */
-		CSB_ERR(csb, "Invalid CRB");
-		return -EINVAL;
-	case CSB_CC_INVALID_DDE:	/* P9 or later */
-		/*
-		 * shouldn't happen, setup_direct/indirect_dde creates
-		 * DDE right
-		 */
-		CSB_ERR(csb, "Invalid DDE");
-		return -EINVAL;
-	case CSB_CC_SEGMENTED_DDL:
-		/* shouldn't happen, setup_ddl creates DDL right */
-		CSB_ERR(csb, "Segmented DDL error");
-		return -EINVAL;
-	case CSB_CC_DDE_OVERFLOW:
-		/* shouldn't happen, setup_ddl creates DDL right */
-		CSB_ERR(csb, "DDE overflow error");
-		return -EINVAL;
-	case CSB_CC_SESSION:
-		/* should not happen with ICSWX */
-		CSB_ERR(csb, "Session violation error");
-		return -EPROTO;
-	case CSB_CC_CHAIN:
-		/* should not happen, we don't use chained CRBs */
-		CSB_ERR(csb, "Chained CRB error");
-		return -EPROTO;
-	case CSB_CC_SEQUENCE:
-		/* should not happen, we don't use chained CRBs */
-		CSB_ERR(csb, "CRB sequence number error");
-		return -EPROTO;
-	case CSB_CC_UNKNOWN_CODE:
-		CSB_ERR(csb, "Unknown subfunction code");
-		return -EPROTO;
-
-	/* hardware errors */
-	case CSB_CC_RD_EXTERNAL:
-	case CSB_CC_RD_EXTERNAL_DUP1:
-	case CSB_CC_RD_EXTERNAL_DUP2:
-	case CSB_CC_RD_EXTERNAL_DUP3:
-		CSB_ERR_ADDR(csb, "Read error outside coprocessor");
-		return -EPROTO;
-	case CSB_CC_WR_EXTERNAL:
-		CSB_ERR_ADDR(csb, "Write error outside coprocessor");
-		return -EPROTO;
-	case CSB_CC_INTERNAL:
-		CSB_ERR(csb, "Internal error in coprocessor");
-		return -EPROTO;
-	case CSB_CC_PROVISION:
-		CSB_ERR(csb, "Storage provision error");
-		return -EPROTO;
-	case CSB_CC_HW:
-		CSB_ERR(csb, "Correctable hardware error");
-		return -EPROTO;
-	case CSB_CC_HW_EXPIRED_TIMER:	/* P9 or later */
-		CSB_ERR(csb, "Job did not finish within allowed time");
-		return -EPROTO;
-
-	default:
-		CSB_ERR(csb, "Invalid CC %d", csb->cc);
-		return -EPROTO;
-	}
-
-	/* check Completion Extension state */
-	if (csb->ce & CSB_CE_TERMINATION) {
-		CSB_ERR(csb, "CSB request was terminated");
-		return -EPROTO;
-	}
-	if (csb->ce & CSB_CE_INCOMPLETE) {
-		CSB_ERR(csb, "CSB request not complete");
-		return -EPROTO;
-	}
-	if (!(csb->ce & CSB_CE_TPBC)) {
-		CSB_ERR(csb, "TPBC not provided, unknown target length");
-		return -EPROTO;
-	}
-
-	/* successful completion */
-	pr_debug_ratelimited("Processed %u bytes in %lu us\n",
-			     be32_to_cpu(csb->count),
-			     (unsigned long)ktime_us_delta(now, start));
-
-	return 0;
-}
-
-static int nx842_config_crb(const unsigned char *in, unsigned int inlen,
-			unsigned char *out, unsigned int outlen,
-			struct nx842_workmem *wmem)
-{
-	struct coprocessor_request_block *crb;
-	struct coprocessor_status_block *csb;
-	u64 csb_addr;
-	int ret;
-
-	crb = &wmem->crb;
-	csb = &crb->csb;
-
-	/* Clear any previous values */
-	memset(crb, 0, sizeof(*crb));
-
-	/* set up DDLs */
-	ret = setup_ddl(&crb->source, wmem->ddl_in,
-			(unsigned char *)in, inlen, true);
-	if (ret)
-		return ret;
-
-	ret = setup_ddl(&crb->target, wmem->ddl_out,
-			out, outlen, false);
-	if (ret)
-		return ret;
-
-	/* set up CRB's CSB addr */
-	csb_addr = nx842_get_pa(csb) & CRB_CSB_ADDRESS;
-	csb_addr |= CRB_CSB_AT; /* Addrs are phys */
-	crb->csb_addr = cpu_to_be64(csb_addr);
-
-	return 0;
-}
-
-/**
- * nx842_exec_icswx - compress/decompress data using the 842 algorithm
- *
- * (De)compression provided by the NX842 coprocessor on IBM PowerNV systems.
- * This compresses or decompresses the provided input buffer into the provided
- * output buffer.
- *
- * Upon return from this function @outlen contains the length of the
- * output data.  If there is an error then @outlen will be 0 and an
- * error will be specified by the return code from this function.
- *
- * The @workmem buffer should only be used by one function call at a time.
- *
- * @in: input buffer pointer
- * @inlen: input buffer size
- * @out: output buffer pointer
- * @outlenp: output buffer size pointer
- * @workmem: working memory buffer pointer, size determined by
- *           nx842_powernv_driver.workmem_size
- * @fc: function code, see CCW Function Codes in nx-842.h
- *
- * Returns:
- *   0		Success, output of length @outlenp stored in the buffer at @out
- *   -ENODEV	Hardware unavailable
- *   -ENOSPC	Output buffer is to small
- *   -EMSGSIZE	Input buffer too large
- *   -EINVAL	buffer constraints do not fix nx842_constraints
- *   -EPROTO	hardware error during operation
- *   -ETIMEDOUT	hardware did not complete operation in reasonable time
- *   -EINTR	operation was aborted
- */
-static int nx842_exec_icswx(const unsigned char *in, unsigned int inlen,
-				  unsigned char *out, unsigned int *outlenp,
-				  void *workmem, int fc)
-{
-	struct coprocessor_request_block *crb;
-	struct coprocessor_status_block *csb;
-	struct nx842_workmem *wmem;
-	int ret;
-	u32 ccw;
-	unsigned int outlen = *outlenp;
-
-	wmem = PTR_ALIGN(workmem, WORKMEM_ALIGN);
-
-	*outlenp = 0;
-
-	/* shoudn't happen, we don't load without a coproc */
-	if (!nx842_ct) {
-		pr_err_ratelimited("coprocessor CT is 0");
-		return -ENODEV;
-	}
-
-	ret = nx842_config_crb(in, inlen, out, outlen, wmem);
-	if (ret)
-		return ret;
-
-	crb = &wmem->crb;
-	csb = &crb->csb;
-
-	/* set up CCW */
-	ccw = 0;
-	ccw = SET_FIELD(CCW_CT, ccw, nx842_ct);
-	ccw = SET_FIELD(CCW_CI_842, ccw, 0); /* use 0 for hw auto-selection */
-	ccw = SET_FIELD(CCW_FC_842, ccw, fc);
-
-	wmem->start = ktime_get();
-
-	/* do ICSWX */
-	ret = icswx(cpu_to_be32(ccw), crb);
-
-	pr_debug_ratelimited("icswx CR %x ccw %x crb->ccw %x\n", ret,
-			     (unsigned int)ccw,
-			     (unsigned int)be32_to_cpu(crb->ccw));
-
-	/*
-	 * NX842 coprocessor sets 3rd bit in CR register with XER[S0].
-	 * XER[S0] is the integer summary overflow bit which is nothing
-	 * to do NX. Since this bit can be set with other return values,
-	 * mask this bit.
-	 */
-	ret &= ~ICSWX_XERS0;
-
-	switch (ret) {
-	case ICSWX_INITIATED:
-		ret = wait_for_csb(wmem, csb);
-		break;
-	case ICSWX_BUSY:
-		pr_debug_ratelimited("842 Coprocessor busy\n");
-		ret = -EBUSY;
-		break;
-	case ICSWX_REJECTED:
-		pr_err_ratelimited("ICSWX rejected\n");
-		ret = -EPROTO;
-		break;
-	}
-
-	if (!ret)
-		*outlenp = be32_to_cpu(csb->count);
-
-	return ret;
-}
-
-/**
- * nx842_exec_vas - compress/decompress data using the 842 algorithm
- *
- * (De)compression provided by the NX842 coprocessor on IBM PowerNV systems.
- * This compresses or decompresses the provided input buffer into the provided
- * output buffer.
- *
- * Upon return from this function @outlen contains the length of the
- * output data.  If there is an error then @outlen will be 0 and an
- * error will be specified by the return code from this function.
- *
- * The @workmem buffer should only be used by one function call at a time.
- *
- * @in: input buffer pointer
- * @inlen: input buffer size
- * @out: output buffer pointer
- * @outlenp: output buffer size pointer
- * @workmem: working memory buffer pointer, size determined by
- *           nx842_powernv_driver.workmem_size
- * @fc: function code, see CCW Function Codes in nx-842.h
- *
- * Returns:
- *   0		Success, output of length @outlenp stored in the buffer
- *		at @out
- *   -ENODEV	Hardware unavailable
- *   -ENOSPC	Output buffer is to small
- *   -EMSGSIZE	Input buffer too large
- *   -EINVAL	buffer constraints do not fix nx842_constraints
- *   -EPROTO	hardware error during operation
- *   -ETIMEDOUT	hardware did not complete operation in reasonable time
- *   -EINTR	operation was aborted
- */
-static int nx842_exec_vas(const unsigned char *in, unsigned int inlen,
-				  unsigned char *out, unsigned int *outlenp,
-				  void *workmem, int fc)
-{
-	struct coprocessor_request_block *crb;
-	struct coprocessor_status_block *csb;
-	struct nx842_workmem *wmem;
-	struct vas_window *txwin;
-	int ret, i = 0;
-	u32 ccw;
-	unsigned int outlen = *outlenp;
-
-	wmem = PTR_ALIGN(workmem, WORKMEM_ALIGN);
-
-	*outlenp = 0;
-
-	crb = &wmem->crb;
-	csb = &crb->csb;
-
-	ret = nx842_config_crb(in, inlen, out, outlen, wmem);
-	if (ret)
-		return ret;
-
-	ccw = 0;
-	ccw = SET_FIELD(CCW_FC_842, ccw, fc);
-	crb->ccw = cpu_to_be32(ccw);
-
-	do {
-		wmem->start = ktime_get();
-		preempt_disable();
-		txwin = this_cpu_read(cpu_txwin);
-
-		/*
-		 * VAS copy CRB into L2 cache. Refer <asm/vas.h>.
-		 * @crb and @offset.
-		 */
-		vas_copy_crb(crb, 0);
-
-		/*
-		 * VAS paste previously copied CRB to NX.
-		 * @txwin, @offset and @last (must be true).
-		 */
-		ret = vas_paste_crb(txwin, 0, 1);
-		preempt_enable();
-		/*
-		 * Retry copy/paste function for VAS failures.
-		 */
-	} while (ret && (i++ < VAS_RETRIES));
-
-	if (ret) {
-		pr_err_ratelimited("VAS copy/paste failed\n");
-		return ret;
-	}
-
-	ret = wait_for_csb(wmem, csb);
-	if (!ret)
-		*outlenp = be32_to_cpu(csb->count);
-
-	return ret;
-}
-
-/**
- * nx842_powernv_compress - Compress data using the 842 algorithm
- *
- * Compression provided by the NX842 coprocessor on IBM PowerNV systems.
- * The input buffer is compressed and the result is stored in the
- * provided output buffer.
- *
- * Upon return from this function @outlen contains the length of the
- * compressed data.  If there is an error then @outlen will be 0 and an
- * error will be specified by the return code from this function.
- *
- * @in: input buffer pointer
- * @inlen: input buffer size
- * @out: output buffer pointer
- * @outlenp: output buffer size pointer
- * @workmem: working memory buffer pointer, size determined by
- *           nx842_powernv_driver.workmem_size
- *
- * Returns: see @nx842_powernv_exec()
- */
-static int nx842_powernv_compress(const unsigned char *in, unsigned int inlen,
-				  unsigned char *out, unsigned int *outlenp,
-				  void *wmem)
-{
-	return nx842_powernv_exec(in, inlen, out, outlenp,
-				      wmem, CCW_FC_842_COMP_CRC);
-}
-
-/**
- * nx842_powernv_decompress - Decompress data using the 842 algorithm
- *
- * Decompression provided by the NX842 coprocessor on IBM PowerNV systems.
- * The input buffer is decompressed and the result is stored in the
- * provided output buffer.
- *
- * Upon return from this function @outlen contains the length of the
- * decompressed data.  If there is an error then @outlen will be 0 and an
- * error will be specified by the return code from this function.
- *
- * @in: input buffer pointer
- * @inlen: input buffer size
- * @out: output buffer pointer
- * @outlenp: output buffer size pointer
- * @workmem: working memory buffer pointer, size determined by
- *           nx842_powernv_driver.workmem_size
- *
- * Returns: see @nx842_powernv_exec()
- */
-static int nx842_powernv_decompress(const unsigned char *in, unsigned int inlen,
-				    unsigned char *out, unsigned int *outlenp,
-				    void *wmem)
-{
-	return nx842_powernv_exec(in, inlen, out, outlenp,
-				      wmem, CCW_FC_842_DECOMP_CRC);
-}
-
-static inline void nx842_add_coprocs_list(struct nx842_coproc *coproc,
-					int chipid)
-{
-	coproc->chip_id = chipid;
-	INIT_LIST_HEAD(&coproc->list);
-	list_add(&coproc->list, &nx842_coprocs);
-}
-
-static struct vas_window *nx842_alloc_txwin(struct nx842_coproc *coproc)
-{
-	struct vas_window *txwin = NULL;
-	struct vas_tx_win_attr txattr;
-
-	/*
-	 * Kernel requests will be high priority. So open send
-	 * windows only for high priority RxFIFO entries.
-	 */
-	vas_init_tx_win_attr(&txattr, coproc->ct);
-	txattr.lpid = 0;	/* lpid is 0 for kernel requests */
-	txattr.pid = 0;		/* pid is 0 for kernel requests */
-
-	/*
-	 * Open a VAS send window which is used to send request to NX.
-	 */
-	txwin = vas_tx_win_open(coproc->vas.id, coproc->ct, &txattr);
-	if (IS_ERR(txwin))
-		pr_err("ibm,nx-842: Can not open TX window: %ld\n",
-				PTR_ERR(txwin));
-
-	return txwin;
-}
-
-/*
- * Identify chip ID for each CPU, open send wndow for the corresponding NX
- * engine and save txwin in percpu cpu_txwin.
- * cpu_txwin is used in copy/paste operation for each compression /
- * decompression request.
- */
-static int nx842_open_percpu_txwins(void)
-{
-	struct nx842_coproc *coproc, *n;
-	unsigned int i, chip_id;
-
-	for_each_possible_cpu(i) {
-		struct vas_window *txwin = NULL;
-
-		chip_id = cpu_to_chip_id(i);
-
-		list_for_each_entry_safe(coproc, n, &nx842_coprocs, list) {
-			/*
-			 * Kernel requests use only high priority FIFOs. So
-			 * open send windows for these FIFOs.
-			 */
-
-			if (coproc->ct != VAS_COP_TYPE_842_HIPRI)
-				continue;
-
-			if (coproc->chip_id == chip_id) {
-				txwin = nx842_alloc_txwin(coproc);
-				if (IS_ERR(txwin))
-					return PTR_ERR(txwin);
-
-				per_cpu(cpu_txwin, i) = txwin;
-				break;
-			}
-		}
-
-		if (!per_cpu(cpu_txwin, i)) {
-			/* shouldn't happen, Each chip will have NX engine */
-			pr_err("NX engine is not available for CPU %d\n", i);
-			return -EINVAL;
-		}
-	}
-
-	return 0;
-}
-
-static int __init vas_cfg_coproc_info(struct device_node *dn, int chip_id,
-					int vasid, int *ct)
-{
-	struct vas_window *rxwin = NULL;
-	struct vas_rx_win_attr rxattr;
-	struct nx842_coproc *coproc;
-	u32 lpid, pid, tid, fifo_size;
-	u64 rx_fifo;
-	const char *priority;
-	int ret;
-
-	ret = of_property_read_u64(dn, "rx-fifo-address", &rx_fifo);
-	if (ret) {
-		pr_err("Missing rx-fifo-address property\n");
-		return ret;
-	}
-
-	ret = of_property_read_u32(dn, "rx-fifo-size", &fifo_size);
-	if (ret) {
-		pr_err("Missing rx-fifo-size property\n");
-		return ret;
-	}
-
-	ret = of_property_read_u32(dn, "lpid", &lpid);
-	if (ret) {
-		pr_err("Missing lpid property\n");
-		return ret;
-	}
-
-	ret = of_property_read_u32(dn, "pid", &pid);
-	if (ret) {
-		pr_err("Missing pid property\n");
-		return ret;
-	}
-
-	ret = of_property_read_u32(dn, "tid", &tid);
-	if (ret) {
-		pr_err("Missing tid property\n");
-		return ret;
-	}
-
-	ret = of_property_read_string(dn, "priority", &priority);
-	if (ret) {
-		pr_err("Missing priority property\n");
-		return ret;
-	}
-
-	coproc = kzalloc(sizeof(*coproc), GFP_KERNEL);
-	if (!coproc)
-		return -ENOMEM;
-
-	if (!strcmp(priority, "High"))
-		coproc->ct = VAS_COP_TYPE_842_HIPRI;
-	else if (!strcmp(priority, "Normal"))
-		coproc->ct = VAS_COP_TYPE_842;
-	else {
-		pr_err("Invalid RxFIFO priority value\n");
-		ret =  -EINVAL;
-		goto err_out;
-	}
-
-	vas_init_rx_win_attr(&rxattr, coproc->ct);
-	rxattr.rx_fifo = (void *)rx_fifo;
-	rxattr.rx_fifo_size = fifo_size;
-	rxattr.lnotify_lpid = lpid;
-	rxattr.lnotify_pid = pid;
-	rxattr.lnotify_tid = tid;
-	/*
-	 * Maximum RX window credits can not be more than #CRBs in
-	 * RxFIFO. Otherwise, can get checkstop if RxFIFO overruns.
-	 */
-	rxattr.wcreds_max = fifo_size / CRB_SIZE;
-
-	/*
-	 * Open a VAS receice window which is used to configure RxFIFO
-	 * for NX.
-	 */
-	rxwin = vas_rx_win_open(vasid, coproc->ct, &rxattr);
-	if (IS_ERR(rxwin)) {
-		ret = PTR_ERR(rxwin);
-		pr_err("setting RxFIFO with VAS failed: %d\n",
-			ret);
-		goto err_out;
-	}
-
-	coproc->vas.rxwin = rxwin;
-	coproc->vas.id = vasid;
-	nx842_add_coprocs_list(coproc, chip_id);
-
-	/*
-	 * (lpid, pid, tid) combination has to be unique for each
-	 * coprocessor instance in the system. So to make it
-	 * unique, skiboot uses coprocessor type such as 842 or
-	 * GZIP for pid and provides this value to kernel in pid
-	 * device-tree property.
-	 */
-	*ct = pid;
-
-	return 0;
-
-err_out:
-	kfree(coproc);
-	return ret;
-}
-
-
-static int __init nx842_powernv_probe_vas(struct device_node *pn)
-{
-	struct device_node *dn;
-	int chip_id, vasid, ret = 0;
-	int nx_fifo_found = 0;
-	int uninitialized_var(ct);
-
-	chip_id = of_get_ibm_chip_id(pn);
-	if (chip_id < 0) {
-		pr_err("ibm,chip-id missing\n");
-		return -EINVAL;
-	}
-
-	vasid = chip_to_vas_id(chip_id);
-	if (vasid < 0) {
-		pr_err("Unable to map chip_id %d to vasid\n", chip_id);
-		return -EINVAL;
-	}
-
-	for_each_child_of_node(pn, dn) {
-		if (of_device_is_compatible(dn, "ibm,p9-nx-842")) {
-			ret = vas_cfg_coproc_info(dn, chip_id, vasid, &ct);
-			if (ret) {
-				of_node_put(dn);
-				return ret;
-			}
-			nx_fifo_found++;
-		}
-	}
-
-	if (!nx_fifo_found) {
-		pr_err("NX842 FIFO nodes are missing\n");
-		return -EINVAL;
-	}
-
-	/*
-	 * Initialize NX instance for both high and normal priority FIFOs.
-	 */
-	if (opal_check_token(OPAL_NX_COPROC_INIT)) {
-		ret = opal_nx_coproc_init(chip_id, ct);
-		if (ret) {
-			pr_err("Failed to initialize NX for chip(%d): %d\n",
-				chip_id, ret);
-			ret = opal_error_code(ret);
-		}
-	} else
-		pr_warn("Firmware doesn't support NX initialization\n");
-
-	return ret;
-}
-
-static int __init nx842_powernv_probe(struct device_node *dn)
-{
-	struct nx842_coproc *coproc;
-	unsigned int ct, ci;
-	int chip_id;
-
-	chip_id = of_get_ibm_chip_id(dn);
-	if (chip_id < 0) {
-		pr_err("ibm,chip-id missing\n");
-		return -EINVAL;
-	}
-
-	if (of_property_read_u32(dn, "ibm,842-coprocessor-type", &ct)) {
-		pr_err("ibm,842-coprocessor-type missing\n");
-		return -EINVAL;
-	}
-
-	if (of_property_read_u32(dn, "ibm,842-coprocessor-instance", &ci)) {
-		pr_err("ibm,842-coprocessor-instance missing\n");
-		return -EINVAL;
-	}
-
-	coproc = kzalloc(sizeof(*coproc), GFP_KERNEL);
-	if (!coproc)
-		return -ENOMEM;
-
-	coproc->ct = ct;
-	coproc->ci = ci;
-	nx842_add_coprocs_list(coproc, chip_id);
-
-	pr_info("coprocessor found on chip %d, CT %d CI %d\n", chip_id, ct, ci);
-
-	if (!nx842_ct)
-		nx842_ct = ct;
-	else if (nx842_ct != ct)
-		pr_err("NX842 chip %d, CT %d != first found CT %d\n",
-		       chip_id, ct, nx842_ct);
-
-	return 0;
-}
-
-static void nx842_delete_coprocs(void)
-{
-	struct nx842_coproc *coproc, *n;
-	struct vas_window *txwin;
-	int i;
-
-	/*
-	 * close percpu txwins that are opened for the corresponding coproc.
-	 */
-	for_each_possible_cpu(i) {
-		txwin = per_cpu(cpu_txwin, i);
-		if (txwin)
-			vas_win_close(txwin);
-
-		per_cpu(cpu_txwin, i) = 0;
-	}
-
-	list_for_each_entry_safe(coproc, n, &nx842_coprocs, list) {
-		if (coproc->vas.rxwin)
-			vas_win_close(coproc->vas.rxwin);
-
-		list_del(&coproc->list);
-		kfree(coproc);
-	}
-}
-
-static struct nx842_constraints nx842_powernv_constraints = {
-	.alignment =	DDE_BUFFER_ALIGN,
-	.multiple =	DDE_BUFFER_LAST_MULT,
-	.minimum =	DDE_BUFFER_LAST_MULT,
-	.maximum =	(DDL_LEN_MAX - 1) * PAGE_SIZE,
-};
-
-static struct nx842_driver nx842_powernv_driver = {
-	.name =		KBUILD_MODNAME,
-	.owner =	THIS_MODULE,
-	.workmem_size =	sizeof(struct nx842_workmem),
-	.constraints =	&nx842_powernv_constraints,
-	.compress =	nx842_powernv_compress,
-	.decompress =	nx842_powernv_decompress,
-};
-
-static int nx842_powernv_crypto_init(struct crypto_tfm *tfm)
-{
-	return nx842_crypto_init(tfm, &nx842_powernv_driver);
-}
-
-static struct crypto_alg nx842_powernv_alg = {
-	.cra_name		= "842",
-	.cra_driver_name	= "842-nx",
-	.cra_priority		= 300,
-	.cra_flags		= CRYPTO_ALG_TYPE_COMPRESS,
-	.cra_ctxsize		= sizeof(struct nx842_crypto_ctx),
-	.cra_module		= THIS_MODULE,
-	.cra_init		= nx842_powernv_crypto_init,
-	.cra_exit		= nx842_crypto_exit,
-	.cra_u			= { .compress = {
-	.coa_compress		= nx842_crypto_compress,
-	.coa_decompress		= nx842_crypto_decompress } }
-};
-
-static __init int nx842_powernv_init(void)
-{
-	struct device_node *dn;
-	int ret;
-
-	/* verify workmem size/align restrictions */
-	BUILD_BUG_ON(WORKMEM_ALIGN % CRB_ALIGN);
-	BUILD_BUG_ON(CRB_ALIGN % DDE_ALIGN);
-	BUILD_BUG_ON(CRB_SIZE % DDE_ALIGN);
-	/* verify buffer size/align restrictions */
-	BUILD_BUG_ON(PAGE_SIZE % DDE_BUFFER_ALIGN);
-	BUILD_BUG_ON(DDE_BUFFER_ALIGN % DDE_BUFFER_SIZE_MULT);
-	BUILD_BUG_ON(DDE_BUFFER_SIZE_MULT % DDE_BUFFER_LAST_MULT);
-
-	for_each_compatible_node(dn, NULL, "ibm,power9-nx") {
-		ret = nx842_powernv_probe_vas(dn);
-		if (ret) {
-			nx842_delete_coprocs();
-			of_node_put(dn);
-			return ret;
-		}
-	}
-
-	if (list_empty(&nx842_coprocs)) {
-		for_each_compatible_node(dn, NULL, "ibm,power-nx")
-			nx842_powernv_probe(dn);
-
-		if (!nx842_ct)
-			return -ENODEV;
-
-		nx842_powernv_exec = nx842_exec_icswx;
-	} else {
-		ret = nx842_open_percpu_txwins();
-		if (ret) {
-			nx842_delete_coprocs();
-			return ret;
-		}
-
-		nx842_powernv_exec = nx842_exec_vas;
-	}
-
-	ret = crypto_register_alg(&nx842_powernv_alg);
-	if (ret) {
-		nx842_delete_coprocs();
-		return ret;
-	}
-
-	return 0;
-}
-module_init(nx842_powernv_init);
-
-static void __exit nx842_powernv_exit(void)
-{
-	crypto_unregister_alg(&nx842_powernv_alg);
-
-	nx842_delete_coprocs();
-}
-module_exit(nx842_powernv_exit);
diff --git a/drivers/crypto/nx/nx-common-powernv.c b/drivers/crypto/nx/nx-common-powernv.c
new file mode 100644
index 0000000..f42881f
--- /dev/null
+++ b/drivers/crypto/nx/nx-common-powernv.c
@@ -0,0 +1,1062 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for IBM PowerNV compression accelerator
+ *
+ * Copyright (C) 2015 Dan Streetman, IBM Corp
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include "nx-842.h"
+
+#include <linux/timer.h>
+
+#include <asm/prom.h>
+#include <asm/icswx.h>
+#include <asm/vas.h>
+#include <asm/reg.h>
+#include <asm/opal-api.h>
+#include <asm/opal.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");
+MODULE_DESCRIPTION("H/W Compression driver for IBM PowerNV processors");
+MODULE_ALIAS_CRYPTO("842");
+MODULE_ALIAS_CRYPTO("842-nx");
+
+#define WORKMEM_ALIGN	(CRB_ALIGN)
+#define CSB_WAIT_MAX	(5000) /* ms */
+#define VAS_RETRIES	(10)
+
+struct nx842_workmem {
+	/* Below fields must be properly aligned */
+	struct coprocessor_request_block crb; /* CRB_ALIGN align */
+	struct data_descriptor_entry ddl_in[DDL_LEN_MAX]; /* DDE_ALIGN align */
+	struct data_descriptor_entry ddl_out[DDL_LEN_MAX]; /* DDE_ALIGN align */
+	/* Above fields must be properly aligned */
+
+	ktime_t start;
+
+	char padding[WORKMEM_ALIGN]; /* unused, to allow alignment */
+} __packed __aligned(WORKMEM_ALIGN);
+
+struct nx842_coproc {
+	unsigned int chip_id;
+	unsigned int ct;
+	unsigned int ci;	/* Coprocessor instance, used with icswx */
+	struct {
+		struct vas_window *rxwin;
+		int id;
+	} vas;
+	struct list_head list;
+};
+
+/*
+ * Send the request to NX engine on the chip for the corresponding CPU
+ * where the process is executing. Use with VAS function.
+ */
+static DEFINE_PER_CPU(struct vas_window *, cpu_txwin);
+
+/* no cpu hotplug on powernv, so this list never changes after init */
+static LIST_HEAD(nx842_coprocs);
+static unsigned int nx842_ct;	/* used in icswx function */
+
+static int (*nx842_powernv_exec)(const unsigned char *in,
+				unsigned int inlen, unsigned char *out,
+				unsigned int *outlenp, void *workmem, int fc);
+
+/**
+ * setup_indirect_dde - Setup an indirect DDE
+ *
+ * The DDE is setup with the the DDE count, byte count, and address of
+ * first direct DDE in the list.
+ */
+static void setup_indirect_dde(struct data_descriptor_entry *dde,
+			       struct data_descriptor_entry *ddl,
+			       unsigned int dde_count, unsigned int byte_count)
+{
+	dde->flags = 0;
+	dde->count = dde_count;
+	dde->index = 0;
+	dde->length = cpu_to_be32(byte_count);
+	dde->address = cpu_to_be64(nx842_get_pa(ddl));
+}
+
+/**
+ * setup_direct_dde - Setup single DDE from buffer
+ *
+ * The DDE is setup with the buffer and length.  The buffer must be properly
+ * aligned.  The used length is returned.
+ * Returns:
+ *   N    Successfully set up DDE with N bytes
+ */
+static unsigned int setup_direct_dde(struct data_descriptor_entry *dde,
+				     unsigned long pa, unsigned int len)
+{
+	unsigned int l = min_t(unsigned int, len, LEN_ON_PAGE(pa));
+
+	dde->flags = 0;
+	dde->count = 0;
+	dde->index = 0;
+	dde->length = cpu_to_be32(l);
+	dde->address = cpu_to_be64(pa);
+
+	return l;
+}
+
+/**
+ * setup_ddl - Setup DDL from buffer
+ *
+ * Returns:
+ *   0		Successfully set up DDL
+ */
+static int setup_ddl(struct data_descriptor_entry *dde,
+		     struct data_descriptor_entry *ddl,
+		     unsigned char *buf, unsigned int len,
+		     bool in)
+{
+	unsigned long pa = nx842_get_pa(buf);
+	int i, ret, total_len = len;
+
+	if (!IS_ALIGNED(pa, DDE_BUFFER_ALIGN)) {
+		pr_debug("%s buffer pa 0x%lx not 0x%x-byte aligned\n",
+			 in ? "input" : "output", pa, DDE_BUFFER_ALIGN);
+		return -EINVAL;
+	}
+
+	/* only need to check last mult; since buffer must be
+	 * DDE_BUFFER_ALIGN aligned, and that is a multiple of
+	 * DDE_BUFFER_SIZE_MULT, and pre-last page DDE buffers
+	 * are guaranteed a multiple of DDE_BUFFER_SIZE_MULT.
+	 */
+	if (len % DDE_BUFFER_LAST_MULT) {
+		pr_debug("%s buffer len 0x%x not a multiple of 0x%x\n",
+			 in ? "input" : "output", len, DDE_BUFFER_LAST_MULT);
+		if (in)
+			return -EINVAL;
+		len = round_down(len, DDE_BUFFER_LAST_MULT);
+	}
+
+	/* use a single direct DDE */
+	if (len <= LEN_ON_PAGE(pa)) {
+		ret = setup_direct_dde(dde, pa, len);
+		WARN_ON(ret < len);
+		return 0;
+	}
+
+	/* use the DDL */
+	for (i = 0; i < DDL_LEN_MAX && len > 0; i++) {
+		ret = setup_direct_dde(&ddl[i], pa, len);
+		buf += ret;
+		len -= ret;
+		pa = nx842_get_pa(buf);
+	}
+
+	if (len > 0) {
+		pr_debug("0x%x total %s bytes 0x%x too many for DDL.\n",
+			 total_len, in ? "input" : "output", len);
+		if (in)
+			return -EMSGSIZE;
+		total_len -= len;
+	}
+	setup_indirect_dde(dde, ddl, i, total_len);
+
+	return 0;
+}
+
+#define CSB_ERR(csb, msg, ...)					\
+	pr_err("ERROR: " msg " : %02x %02x %02x %02x %08x\n",	\
+	       ##__VA_ARGS__, (csb)->flags,			\
+	       (csb)->cs, (csb)->cc, (csb)->ce,			\
+	       be32_to_cpu((csb)->count))
+
+#define CSB_ERR_ADDR(csb, msg, ...)				\
+	CSB_ERR(csb, msg " at %lx", ##__VA_ARGS__,		\
+		(unsigned long)be64_to_cpu((csb)->address))
+
+/**
+ * wait_for_csb
+ */
+static int wait_for_csb(struct nx842_workmem *wmem,
+			struct coprocessor_status_block *csb)
+{
+	ktime_t start = wmem->start, now = ktime_get();
+	ktime_t timeout = ktime_add_ms(start, CSB_WAIT_MAX);
+
+	while (!(READ_ONCE(csb->flags) & CSB_V)) {
+		cpu_relax();
+		now = ktime_get();
+		if (ktime_after(now, timeout))
+			break;
+	}
+
+	/* hw has updated csb and output buffer */
+	barrier();
+
+	/* check CSB flags */
+	if (!(csb->flags & CSB_V)) {
+		CSB_ERR(csb, "CSB still not valid after %ld us, giving up",
+			(long)ktime_us_delta(now, start));
+		return -ETIMEDOUT;
+	}
+	if (csb->flags & CSB_F) {
+		CSB_ERR(csb, "Invalid CSB format");
+		return -EPROTO;
+	}
+	if (csb->flags & CSB_CH) {
+		CSB_ERR(csb, "Invalid CSB chaining state");
+		return -EPROTO;
+	}
+
+	/* verify CSB completion sequence is 0 */
+	if (csb->cs) {
+		CSB_ERR(csb, "Invalid CSB completion sequence");
+		return -EPROTO;
+	}
+
+	/* check CSB Completion Code */
+	switch (csb->cc) {
+	/* no error */
+	case CSB_CC_SUCCESS:
+		break;
+	case CSB_CC_TPBC_GT_SPBC:
+		/* not an error, but the compressed data is
+		 * larger than the uncompressed data :(
+		 */
+		break;
+
+	/* input data errors */
+	case CSB_CC_OPERAND_OVERLAP:
+		/* input and output buffers overlap */
+		CSB_ERR(csb, "Operand Overlap error");
+		return -EINVAL;
+	case CSB_CC_INVALID_OPERAND:
+		CSB_ERR(csb, "Invalid operand");
+		return -EINVAL;
+	case CSB_CC_NOSPC:
+		/* output buffer too small */
+		return -ENOSPC;
+	case CSB_CC_ABORT:
+		CSB_ERR(csb, "Function aborted");
+		return -EINTR;
+	case CSB_CC_CRC_MISMATCH:
+		CSB_ERR(csb, "CRC mismatch");
+		return -EINVAL;
+	case CSB_CC_TEMPL_INVALID:
+		CSB_ERR(csb, "Compressed data template invalid");
+		return -EINVAL;
+	case CSB_CC_TEMPL_OVERFLOW:
+		CSB_ERR(csb, "Compressed data template shows data past end");
+		return -EINVAL;
+	case CSB_CC_EXCEED_BYTE_COUNT:	/* P9 or later */
+		/*
+		 * DDE byte count exceeds the limit specified in Maximum
+		 * byte count register.
+		 */
+		CSB_ERR(csb, "DDE byte count exceeds the limit");
+		return -EINVAL;
+
+	/* these should not happen */
+	case CSB_CC_INVALID_ALIGN:
+		/* setup_ddl should have detected this */
+		CSB_ERR_ADDR(csb, "Invalid alignment");
+		return -EINVAL;
+	case CSB_CC_DATA_LENGTH:
+		/* setup_ddl should have detected this */
+		CSB_ERR(csb, "Invalid data length");
+		return -EINVAL;
+	case CSB_CC_WR_TRANSLATION:
+	case CSB_CC_TRANSLATION:
+	case CSB_CC_TRANSLATION_DUP1:
+	case CSB_CC_TRANSLATION_DUP2:
+	case CSB_CC_TRANSLATION_DUP3:
+	case CSB_CC_TRANSLATION_DUP4:
+	case CSB_CC_TRANSLATION_DUP5:
+	case CSB_CC_TRANSLATION_DUP6:
+		/* should not happen, we use physical addrs */
+		CSB_ERR_ADDR(csb, "Translation error");
+		return -EPROTO;
+	case CSB_CC_WR_PROTECTION:
+	case CSB_CC_PROTECTION:
+	case CSB_CC_PROTECTION_DUP1:
+	case CSB_CC_PROTECTION_DUP2:
+	case CSB_CC_PROTECTION_DUP3:
+	case CSB_CC_PROTECTION_DUP4:
+	case CSB_CC_PROTECTION_DUP5:
+	case CSB_CC_PROTECTION_DUP6:
+		/* should not happen, we use physical addrs */
+		CSB_ERR_ADDR(csb, "Protection error");
+		return -EPROTO;
+	case CSB_CC_PRIVILEGE:
+		/* shouldn't happen, we're in HYP mode */
+		CSB_ERR(csb, "Insufficient Privilege error");
+		return -EPROTO;
+	case CSB_CC_EXCESSIVE_DDE:
+		/* shouldn't happen, setup_ddl doesn't use many dde's */
+		CSB_ERR(csb, "Too many DDEs in DDL");
+		return -EINVAL;
+	case CSB_CC_TRANSPORT:
+	case CSB_CC_INVALID_CRB:	/* P9 or later */
+		/* shouldn't happen, we setup CRB correctly */
+		CSB_ERR(csb, "Invalid CRB");
+		return -EINVAL;
+	case CSB_CC_INVALID_DDE:	/* P9 or later */
+		/*
+		 * shouldn't happen, setup_direct/indirect_dde creates
+		 * DDE right
+		 */
+		CSB_ERR(csb, "Invalid DDE");
+		return -EINVAL;
+	case CSB_CC_SEGMENTED_DDL:
+		/* shouldn't happen, setup_ddl creates DDL right */
+		CSB_ERR(csb, "Segmented DDL error");
+		return -EINVAL;
+	case CSB_CC_DDE_OVERFLOW:
+		/* shouldn't happen, setup_ddl creates DDL right */
+		CSB_ERR(csb, "DDE overflow error");
+		return -EINVAL;
+	case CSB_CC_SESSION:
+		/* should not happen with ICSWX */
+		CSB_ERR(csb, "Session violation error");
+		return -EPROTO;
+	case CSB_CC_CHAIN:
+		/* should not happen, we don't use chained CRBs */
+		CSB_ERR(csb, "Chained CRB error");
+		return -EPROTO;
+	case CSB_CC_SEQUENCE:
+		/* should not happen, we don't use chained CRBs */
+		CSB_ERR(csb, "CRB sequence number error");
+		return -EPROTO;
+	case CSB_CC_UNKNOWN_CODE:
+		CSB_ERR(csb, "Unknown subfunction code");
+		return -EPROTO;
+
+	/* hardware errors */
+	case CSB_CC_RD_EXTERNAL:
+	case CSB_CC_RD_EXTERNAL_DUP1:
+	case CSB_CC_RD_EXTERNAL_DUP2:
+	case CSB_CC_RD_EXTERNAL_DUP3:
+		CSB_ERR_ADDR(csb, "Read error outside coprocessor");
+		return -EPROTO;
+	case CSB_CC_WR_EXTERNAL:
+		CSB_ERR_ADDR(csb, "Write error outside coprocessor");
+		return -EPROTO;
+	case CSB_CC_INTERNAL:
+		CSB_ERR(csb, "Internal error in coprocessor");
+		return -EPROTO;
+	case CSB_CC_PROVISION:
+		CSB_ERR(csb, "Storage provision error");
+		return -EPROTO;
+	case CSB_CC_HW:
+		CSB_ERR(csb, "Correctable hardware error");
+		return -EPROTO;
+	case CSB_CC_HW_EXPIRED_TIMER:	/* P9 or later */
+		CSB_ERR(csb, "Job did not finish within allowed time");
+		return -EPROTO;
+
+	default:
+		CSB_ERR(csb, "Invalid CC %d", csb->cc);
+		return -EPROTO;
+	}
+
+	/* check Completion Extension state */
+	if (csb->ce & CSB_CE_TERMINATION) {
+		CSB_ERR(csb, "CSB request was terminated");
+		return -EPROTO;
+	}
+	if (csb->ce & CSB_CE_INCOMPLETE) {
+		CSB_ERR(csb, "CSB request not complete");
+		return -EPROTO;
+	}
+	if (!(csb->ce & CSB_CE_TPBC)) {
+		CSB_ERR(csb, "TPBC not provided, unknown target length");
+		return -EPROTO;
+	}
+
+	/* successful completion */
+	pr_debug_ratelimited("Processed %u bytes in %lu us\n",
+			     be32_to_cpu(csb->count),
+			     (unsigned long)ktime_us_delta(now, start));
+
+	return 0;
+}
+
+static int nx842_config_crb(const unsigned char *in, unsigned int inlen,
+			unsigned char *out, unsigned int outlen,
+			struct nx842_workmem *wmem)
+{
+	struct coprocessor_request_block *crb;
+	struct coprocessor_status_block *csb;
+	u64 csb_addr;
+	int ret;
+
+	crb = &wmem->crb;
+	csb = &crb->csb;
+
+	/* Clear any previous values */
+	memset(crb, 0, sizeof(*crb));
+
+	/* set up DDLs */
+	ret = setup_ddl(&crb->source, wmem->ddl_in,
+			(unsigned char *)in, inlen, true);
+	if (ret)
+		return ret;
+
+	ret = setup_ddl(&crb->target, wmem->ddl_out,
+			out, outlen, false);
+	if (ret)
+		return ret;
+
+	/* set up CRB's CSB addr */
+	csb_addr = nx842_get_pa(csb) & CRB_CSB_ADDRESS;
+	csb_addr |= CRB_CSB_AT; /* Addrs are phys */
+	crb->csb_addr = cpu_to_be64(csb_addr);
+
+	return 0;
+}
+
+/**
+ * nx842_exec_icswx - compress/decompress data using the 842 algorithm
+ *
+ * (De)compression provided by the NX842 coprocessor on IBM PowerNV systems.
+ * This compresses or decompresses the provided input buffer into the provided
+ * output buffer.
+ *
+ * Upon return from this function @outlen contains the length of the
+ * output data.  If there is an error then @outlen will be 0 and an
+ * error will be specified by the return code from this function.
+ *
+ * The @workmem buffer should only be used by one function call at a time.
+ *
+ * @in: input buffer pointer
+ * @inlen: input buffer size
+ * @out: output buffer pointer
+ * @outlenp: output buffer size pointer
+ * @workmem: working memory buffer pointer, size determined by
+ *           nx842_powernv_driver.workmem_size
+ * @fc: function code, see CCW Function Codes in nx-842.h
+ *
+ * Returns:
+ *   0		Success, output of length @outlenp stored in the buffer at @out
+ *   -ENODEV	Hardware unavailable
+ *   -ENOSPC	Output buffer is to small
+ *   -EMSGSIZE	Input buffer too large
+ *   -EINVAL	buffer constraints do not fix nx842_constraints
+ *   -EPROTO	hardware error during operation
+ *   -ETIMEDOUT	hardware did not complete operation in reasonable time
+ *   -EINTR	operation was aborted
+ */
+static int nx842_exec_icswx(const unsigned char *in, unsigned int inlen,
+				  unsigned char *out, unsigned int *outlenp,
+				  void *workmem, int fc)
+{
+	struct coprocessor_request_block *crb;
+	struct coprocessor_status_block *csb;
+	struct nx842_workmem *wmem;
+	int ret;
+	u32 ccw;
+	unsigned int outlen = *outlenp;
+
+	wmem = PTR_ALIGN(workmem, WORKMEM_ALIGN);
+
+	*outlenp = 0;
+
+	/* shoudn't happen, we don't load without a coproc */
+	if (!nx842_ct) {
+		pr_err_ratelimited("coprocessor CT is 0");
+		return -ENODEV;
+	}
+
+	ret = nx842_config_crb(in, inlen, out, outlen, wmem);
+	if (ret)
+		return ret;
+
+	crb = &wmem->crb;
+	csb = &crb->csb;
+
+	/* set up CCW */
+	ccw = 0;
+	ccw = SET_FIELD(CCW_CT, ccw, nx842_ct);
+	ccw = SET_FIELD(CCW_CI_842, ccw, 0); /* use 0 for hw auto-selection */
+	ccw = SET_FIELD(CCW_FC_842, ccw, fc);
+
+	wmem->start = ktime_get();
+
+	/* do ICSWX */
+	ret = icswx(cpu_to_be32(ccw), crb);
+
+	pr_debug_ratelimited("icswx CR %x ccw %x crb->ccw %x\n", ret,
+			     (unsigned int)ccw,
+			     (unsigned int)be32_to_cpu(crb->ccw));
+
+	/*
+	 * NX842 coprocessor sets 3rd bit in CR register with XER[S0].
+	 * XER[S0] is the integer summary overflow bit which is nothing
+	 * to do NX. Since this bit can be set with other return values,
+	 * mask this bit.
+	 */
+	ret &= ~ICSWX_XERS0;
+
+	switch (ret) {
+	case ICSWX_INITIATED:
+		ret = wait_for_csb(wmem, csb);
+		break;
+	case ICSWX_BUSY:
+		pr_debug_ratelimited("842 Coprocessor busy\n");
+		ret = -EBUSY;
+		break;
+	case ICSWX_REJECTED:
+		pr_err_ratelimited("ICSWX rejected\n");
+		ret = -EPROTO;
+		break;
+	}
+
+	if (!ret)
+		*outlenp = be32_to_cpu(csb->count);
+
+	return ret;
+}
+
+/**
+ * nx842_exec_vas - compress/decompress data using the 842 algorithm
+ *
+ * (De)compression provided by the NX842 coprocessor on IBM PowerNV systems.
+ * This compresses or decompresses the provided input buffer into the provided
+ * output buffer.
+ *
+ * Upon return from this function @outlen contains the length of the
+ * output data.  If there is an error then @outlen will be 0 and an
+ * error will be specified by the return code from this function.
+ *
+ * The @workmem buffer should only be used by one function call at a time.
+ *
+ * @in: input buffer pointer
+ * @inlen: input buffer size
+ * @out: output buffer pointer
+ * @outlenp: output buffer size pointer
+ * @workmem: working memory buffer pointer, size determined by
+ *           nx842_powernv_driver.workmem_size
+ * @fc: function code, see CCW Function Codes in nx-842.h
+ *
+ * Returns:
+ *   0		Success, output of length @outlenp stored in the buffer
+ *		at @out
+ *   -ENODEV	Hardware unavailable
+ *   -ENOSPC	Output buffer is to small
+ *   -EMSGSIZE	Input buffer too large
+ *   -EINVAL	buffer constraints do not fix nx842_constraints
+ *   -EPROTO	hardware error during operation
+ *   -ETIMEDOUT	hardware did not complete operation in reasonable time
+ *   -EINTR	operation was aborted
+ */
+static int nx842_exec_vas(const unsigned char *in, unsigned int inlen,
+				  unsigned char *out, unsigned int *outlenp,
+				  void *workmem, int fc)
+{
+	struct coprocessor_request_block *crb;
+	struct coprocessor_status_block *csb;
+	struct nx842_workmem *wmem;
+	struct vas_window *txwin;
+	int ret, i = 0;
+	u32 ccw;
+	unsigned int outlen = *outlenp;
+
+	wmem = PTR_ALIGN(workmem, WORKMEM_ALIGN);
+
+	*outlenp = 0;
+
+	crb = &wmem->crb;
+	csb = &crb->csb;
+
+	ret = nx842_config_crb(in, inlen, out, outlen, wmem);
+	if (ret)
+		return ret;
+
+	ccw = 0;
+	ccw = SET_FIELD(CCW_FC_842, ccw, fc);
+	crb->ccw = cpu_to_be32(ccw);
+
+	do {
+		wmem->start = ktime_get();
+		preempt_disable();
+		txwin = this_cpu_read(cpu_txwin);
+
+		/*
+		 * VAS copy CRB into L2 cache. Refer <asm/vas.h>.
+		 * @crb and @offset.
+		 */
+		vas_copy_crb(crb, 0);
+
+		/*
+		 * VAS paste previously copied CRB to NX.
+		 * @txwin, @offset and @last (must be true).
+		 */
+		ret = vas_paste_crb(txwin, 0, 1);
+		preempt_enable();
+		/*
+		 * Retry copy/paste function for VAS failures.
+		 */
+	} while (ret && (i++ < VAS_RETRIES));
+
+	if (ret) {
+		pr_err_ratelimited("VAS copy/paste failed\n");
+		return ret;
+	}
+
+	ret = wait_for_csb(wmem, csb);
+	if (!ret)
+		*outlenp = be32_to_cpu(csb->count);
+
+	return ret;
+}
+
+/**
+ * nx842_powernv_compress - Compress data using the 842 algorithm
+ *
+ * Compression provided by the NX842 coprocessor on IBM PowerNV systems.
+ * The input buffer is compressed and the result is stored in the
+ * provided output buffer.
+ *
+ * Upon return from this function @outlen contains the length of the
+ * compressed data.  If there is an error then @outlen will be 0 and an
+ * error will be specified by the return code from this function.
+ *
+ * @in: input buffer pointer
+ * @inlen: input buffer size
+ * @out: output buffer pointer
+ * @outlenp: output buffer size pointer
+ * @workmem: working memory buffer pointer, size determined by
+ *           nx842_powernv_driver.workmem_size
+ *
+ * Returns: see @nx842_powernv_exec()
+ */
+static int nx842_powernv_compress(const unsigned char *in, unsigned int inlen,
+				  unsigned char *out, unsigned int *outlenp,
+				  void *wmem)
+{
+	return nx842_powernv_exec(in, inlen, out, outlenp,
+				      wmem, CCW_FC_842_COMP_CRC);
+}
+
+/**
+ * nx842_powernv_decompress - Decompress data using the 842 algorithm
+ *
+ * Decompression provided by the NX842 coprocessor on IBM PowerNV systems.
+ * The input buffer is decompressed and the result is stored in the
+ * provided output buffer.
+ *
+ * Upon return from this function @outlen contains the length of the
+ * decompressed data.  If there is an error then @outlen will be 0 and an
+ * error will be specified by the return code from this function.
+ *
+ * @in: input buffer pointer
+ * @inlen: input buffer size
+ * @out: output buffer pointer
+ * @outlenp: output buffer size pointer
+ * @workmem: working memory buffer pointer, size determined by
+ *           nx842_powernv_driver.workmem_size
+ *
+ * Returns: see @nx842_powernv_exec()
+ */
+static int nx842_powernv_decompress(const unsigned char *in, unsigned int inlen,
+				    unsigned char *out, unsigned int *outlenp,
+				    void *wmem)
+{
+	return nx842_powernv_exec(in, inlen, out, outlenp,
+				      wmem, CCW_FC_842_DECOMP_CRC);
+}
+
+static inline void nx842_add_coprocs_list(struct nx842_coproc *coproc,
+					int chipid)
+{
+	coproc->chip_id = chipid;
+	INIT_LIST_HEAD(&coproc->list);
+	list_add(&coproc->list, &nx842_coprocs);
+}
+
+static struct vas_window *nx842_alloc_txwin(struct nx842_coproc *coproc)
+{
+	struct vas_window *txwin = NULL;
+	struct vas_tx_win_attr txattr;
+
+	/*
+	 * Kernel requests will be high priority. So open send
+	 * windows only for high priority RxFIFO entries.
+	 */
+	vas_init_tx_win_attr(&txattr, coproc->ct);
+	txattr.lpid = 0;	/* lpid is 0 for kernel requests */
+	txattr.pid = 0;		/* pid is 0 for kernel requests */
+
+	/*
+	 * Open a VAS send window which is used to send request to NX.
+	 */
+	txwin = vas_tx_win_open(coproc->vas.id, coproc->ct, &txattr);
+	if (IS_ERR(txwin))
+		pr_err("ibm,nx-842: Can not open TX window: %ld\n",
+				PTR_ERR(txwin));
+
+	return txwin;
+}
+
+/*
+ * Identify chip ID for each CPU, open send wndow for the corresponding NX
+ * engine and save txwin in percpu cpu_txwin.
+ * cpu_txwin is used in copy/paste operation for each compression /
+ * decompression request.
+ */
+static int nx842_open_percpu_txwins(void)
+{
+	struct nx842_coproc *coproc, *n;
+	unsigned int i, chip_id;
+
+	for_each_possible_cpu(i) {
+		struct vas_window *txwin = NULL;
+
+		chip_id = cpu_to_chip_id(i);
+
+		list_for_each_entry_safe(coproc, n, &nx842_coprocs, list) {
+			/*
+			 * Kernel requests use only high priority FIFOs. So
+			 * open send windows for these FIFOs.
+			 */
+
+			if (coproc->ct != VAS_COP_TYPE_842_HIPRI)
+				continue;
+
+			if (coproc->chip_id == chip_id) {
+				txwin = nx842_alloc_txwin(coproc);
+				if (IS_ERR(txwin))
+					return PTR_ERR(txwin);
+
+				per_cpu(cpu_txwin, i) = txwin;
+				break;
+			}
+		}
+
+		if (!per_cpu(cpu_txwin, i)) {
+			/* shouldn't happen, Each chip will have NX engine */
+			pr_err("NX engine is not available for CPU %d\n", i);
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+static int __init vas_cfg_coproc_info(struct device_node *dn, int chip_id,
+					int vasid, int *ct)
+{
+	struct vas_window *rxwin = NULL;
+	struct vas_rx_win_attr rxattr;
+	struct nx842_coproc *coproc;
+	u32 lpid, pid, tid, fifo_size;
+	u64 rx_fifo;
+	const char *priority;
+	int ret;
+
+	ret = of_property_read_u64(dn, "rx-fifo-address", &rx_fifo);
+	if (ret) {
+		pr_err("Missing rx-fifo-address property\n");
+		return ret;
+	}
+
+	ret = of_property_read_u32(dn, "rx-fifo-size", &fifo_size);
+	if (ret) {
+		pr_err("Missing rx-fifo-size property\n");
+		return ret;
+	}
+
+	ret = of_property_read_u32(dn, "lpid", &lpid);
+	if (ret) {
+		pr_err("Missing lpid property\n");
+		return ret;
+	}
+
+	ret = of_property_read_u32(dn, "pid", &pid);
+	if (ret) {
+		pr_err("Missing pid property\n");
+		return ret;
+	}
+
+	ret = of_property_read_u32(dn, "tid", &tid);
+	if (ret) {
+		pr_err("Missing tid property\n");
+		return ret;
+	}
+
+	ret = of_property_read_string(dn, "priority", &priority);
+	if (ret) {
+		pr_err("Missing priority property\n");
+		return ret;
+	}
+
+	coproc = kzalloc(sizeof(*coproc), GFP_KERNEL);
+	if (!coproc)
+		return -ENOMEM;
+
+	if (!strcmp(priority, "High"))
+		coproc->ct = VAS_COP_TYPE_842_HIPRI;
+	else if (!strcmp(priority, "Normal"))
+		coproc->ct = VAS_COP_TYPE_842;
+	else {
+		pr_err("Invalid RxFIFO priority value\n");
+		ret =  -EINVAL;
+		goto err_out;
+	}
+
+	vas_init_rx_win_attr(&rxattr, coproc->ct);
+	rxattr.rx_fifo = (void *)rx_fifo;
+	rxattr.rx_fifo_size = fifo_size;
+	rxattr.lnotify_lpid = lpid;
+	rxattr.lnotify_pid = pid;
+	rxattr.lnotify_tid = tid;
+	/*
+	 * Maximum RX window credits can not be more than #CRBs in
+	 * RxFIFO. Otherwise, can get checkstop if RxFIFO overruns.
+	 */
+	rxattr.wcreds_max = fifo_size / CRB_SIZE;
+
+	/*
+	 * Open a VAS receice window which is used to configure RxFIFO
+	 * for NX.
+	 */
+	rxwin = vas_rx_win_open(vasid, coproc->ct, &rxattr);
+	if (IS_ERR(rxwin)) {
+		ret = PTR_ERR(rxwin);
+		pr_err("setting RxFIFO with VAS failed: %d\n",
+			ret);
+		goto err_out;
+	}
+
+	coproc->vas.rxwin = rxwin;
+	coproc->vas.id = vasid;
+	nx842_add_coprocs_list(coproc, chip_id);
+
+	/*
+	 * (lpid, pid, tid) combination has to be unique for each
+	 * coprocessor instance in the system. So to make it
+	 * unique, skiboot uses coprocessor type such as 842 or
+	 * GZIP for pid and provides this value to kernel in pid
+	 * device-tree property.
+	 */
+	*ct = pid;
+
+	return 0;
+
+err_out:
+	kfree(coproc);
+	return ret;
+}
+
+
+static int __init nx842_powernv_probe_vas(struct device_node *pn)
+{
+	struct device_node *dn;
+	int chip_id, vasid, ret = 0;
+	int nx_fifo_found = 0;
+	int uninitialized_var(ct);
+
+	chip_id = of_get_ibm_chip_id(pn);
+	if (chip_id < 0) {
+		pr_err("ibm,chip-id missing\n");
+		return -EINVAL;
+	}
+
+	vasid = chip_to_vas_id(chip_id);
+	if (vasid < 0) {
+		pr_err("Unable to map chip_id %d to vasid\n", chip_id);
+		return -EINVAL;
+	}
+
+	for_each_child_of_node(pn, dn) {
+		if (of_device_is_compatible(dn, "ibm,p9-nx-842")) {
+			ret = vas_cfg_coproc_info(dn, chip_id, vasid, &ct);
+			if (ret) {
+				of_node_put(dn);
+				return ret;
+			}
+			nx_fifo_found++;
+		}
+	}
+
+	if (!nx_fifo_found) {
+		pr_err("NX842 FIFO nodes are missing\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Initialize NX instance for both high and normal priority FIFOs.
+	 */
+	if (opal_check_token(OPAL_NX_COPROC_INIT)) {
+		ret = opal_nx_coproc_init(chip_id, ct);
+		if (ret) {
+			pr_err("Failed to initialize NX for chip(%d): %d\n",
+				chip_id, ret);
+			ret = opal_error_code(ret);
+		}
+	} else
+		pr_warn("Firmware doesn't support NX initialization\n");
+
+	return ret;
+}
+
+static int __init nx842_powernv_probe(struct device_node *dn)
+{
+	struct nx842_coproc *coproc;
+	unsigned int ct, ci;
+	int chip_id;
+
+	chip_id = of_get_ibm_chip_id(dn);
+	if (chip_id < 0) {
+		pr_err("ibm,chip-id missing\n");
+		return -EINVAL;
+	}
+
+	if (of_property_read_u32(dn, "ibm,842-coprocessor-type", &ct)) {
+		pr_err("ibm,842-coprocessor-type missing\n");
+		return -EINVAL;
+	}
+
+	if (of_property_read_u32(dn, "ibm,842-coprocessor-instance", &ci)) {
+		pr_err("ibm,842-coprocessor-instance missing\n");
+		return -EINVAL;
+	}
+
+	coproc = kzalloc(sizeof(*coproc), GFP_KERNEL);
+	if (!coproc)
+		return -ENOMEM;
+
+	coproc->ct = ct;
+	coproc->ci = ci;
+	nx842_add_coprocs_list(coproc, chip_id);
+
+	pr_info("coprocessor found on chip %d, CT %d CI %d\n", chip_id, ct, ci);
+
+	if (!nx842_ct)
+		nx842_ct = ct;
+	else if (nx842_ct != ct)
+		pr_err("NX842 chip %d, CT %d != first found CT %d\n",
+		       chip_id, ct, nx842_ct);
+
+	return 0;
+}
+
+static void nx842_delete_coprocs(void)
+{
+	struct nx842_coproc *coproc, *n;
+	struct vas_window *txwin;
+	int i;
+
+	/*
+	 * close percpu txwins that are opened for the corresponding coproc.
+	 */
+	for_each_possible_cpu(i) {
+		txwin = per_cpu(cpu_txwin, i);
+		if (txwin)
+			vas_win_close(txwin);
+
+		per_cpu(cpu_txwin, i) = 0;
+	}
+
+	list_for_each_entry_safe(coproc, n, &nx842_coprocs, list) {
+		if (coproc->vas.rxwin)
+			vas_win_close(coproc->vas.rxwin);
+
+		list_del(&coproc->list);
+		kfree(coproc);
+	}
+}
+
+static struct nx842_constraints nx842_powernv_constraints = {
+	.alignment =	DDE_BUFFER_ALIGN,
+	.multiple =	DDE_BUFFER_LAST_MULT,
+	.minimum =	DDE_BUFFER_LAST_MULT,
+	.maximum =	(DDL_LEN_MAX - 1) * PAGE_SIZE,
+};
+
+static struct nx842_driver nx842_powernv_driver = {
+	.name =		KBUILD_MODNAME,
+	.owner =	THIS_MODULE,
+	.workmem_size =	sizeof(struct nx842_workmem),
+	.constraints =	&nx842_powernv_constraints,
+	.compress =	nx842_powernv_compress,
+	.decompress =	nx842_powernv_decompress,
+};
+
+static int nx842_powernv_crypto_init(struct crypto_tfm *tfm)
+{
+	return nx842_crypto_init(tfm, &nx842_powernv_driver);
+}
+
+static struct crypto_alg nx842_powernv_alg = {
+	.cra_name		= "842",
+	.cra_driver_name	= "842-nx",
+	.cra_priority		= 300,
+	.cra_flags		= CRYPTO_ALG_TYPE_COMPRESS,
+	.cra_ctxsize		= sizeof(struct nx842_crypto_ctx),
+	.cra_module		= THIS_MODULE,
+	.cra_init		= nx842_powernv_crypto_init,
+	.cra_exit		= nx842_crypto_exit,
+	.cra_u			= { .compress = {
+	.coa_compress		= nx842_crypto_compress,
+	.coa_decompress		= nx842_crypto_decompress } }
+};
+
+static __init int nx842_powernv_init(void)
+{
+	struct device_node *dn;
+	int ret;
+
+	/* verify workmem size/align restrictions */
+	BUILD_BUG_ON(WORKMEM_ALIGN % CRB_ALIGN);
+	BUILD_BUG_ON(CRB_ALIGN % DDE_ALIGN);
+	BUILD_BUG_ON(CRB_SIZE % DDE_ALIGN);
+	/* verify buffer size/align restrictions */
+	BUILD_BUG_ON(PAGE_SIZE % DDE_BUFFER_ALIGN);
+	BUILD_BUG_ON(DDE_BUFFER_ALIGN % DDE_BUFFER_SIZE_MULT);
+	BUILD_BUG_ON(DDE_BUFFER_SIZE_MULT % DDE_BUFFER_LAST_MULT);
+
+	for_each_compatible_node(dn, NULL, "ibm,power9-nx") {
+		ret = nx842_powernv_probe_vas(dn);
+		if (ret) {
+			nx842_delete_coprocs();
+			of_node_put(dn);
+			return ret;
+		}
+	}
+
+	if (list_empty(&nx842_coprocs)) {
+		for_each_compatible_node(dn, NULL, "ibm,power-nx")
+			nx842_powernv_probe(dn);
+
+		if (!nx842_ct)
+			return -ENODEV;
+
+		nx842_powernv_exec = nx842_exec_icswx;
+	} else {
+		ret = nx842_open_percpu_txwins();
+		if (ret) {
+			nx842_delete_coprocs();
+			return ret;
+		}
+
+		nx842_powernv_exec = nx842_exec_vas;
+	}
+
+	ret = crypto_register_alg(&nx842_powernv_alg);
+	if (ret) {
+		nx842_delete_coprocs();
+		return ret;
+	}
+
+	return 0;
+}
+module_init(nx842_powernv_init);
+
+static void __exit nx842_powernv_exit(void)
+{
+	crypto_unregister_alg(&nx842_powernv_alg);
+
+	nx842_delete_coprocs();
+}
+module_exit(nx842_powernv_exit);
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v5 4/9] crypto/nx: Initialize coproc entry with kzalloc
From: Haren Myneni @ 2020-04-01 22:04 UTC (permalink / raw)
  To: mpe; +Cc: mikey, herbert, npiggin, linux-crypto, sukadev, linuxppc-dev, dja
In-Reply-To: <1585777592.10664.462.camel@hbabu-laptop>


coproc entry is initialized during NX probe on power9, but not on P8.
nx842_delete_coprocs() is used for both and frees receive window if it
is allocated. Getting crash for rmmod on P8 since coproc->vas.rxwin
is not initialized.

This patch replaces kmalloc with kzalloc in nx842_powernv_probe()

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 drivers/crypto/nx/nx-842-powernv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/crypto/nx/nx-842-powernv.c b/drivers/crypto/nx/nx-842-powernv.c
index c037a24..8e63326 100644
--- a/drivers/crypto/nx/nx-842-powernv.c
+++ b/drivers/crypto/nx/nx-842-powernv.c
@@ -922,7 +922,7 @@ static int __init nx842_powernv_probe(struct device_node *dn)
 		return -EINVAL;
 	}
 
-	coproc = kmalloc(sizeof(*coproc), GFP_KERNEL);
+	coproc = kzalloc(sizeof(*coproc), GFP_KERNEL);
 	if (!coproc)
 		return -ENOMEM;
 
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v5 3/9] powerpc/vas: Add VAS user space API
From: Haren Myneni @ 2020-04-01 21:59 UTC (permalink / raw)
  To: mpe; +Cc: mikey, herbert, npiggin, linux-crypto, sukadev, linuxppc-dev, dja
In-Reply-To: <1585777592.10664.462.camel@hbabu-laptop>


On power9, user space can send GZIP compression requests directly to NX
once kernel establishes NX channel / window with VAS. This patch provides
user space API which allows user space to establish channel using open
VAS_TX_WIN_OPEN ioctl, mmap and close operations.

Each window corresponds to file descriptor and application can open
multiple windows. After the window is opened, VAS_TX_WIN_OPEN icoctl to
open a window on specific VAS instance, mmap() system call to map
the hardware address of engine's request queue into the application's
virtual address space.

Then the application can then submit one or more requests to the the
engine by using the copy/paste instructions and pasting the CRBs to
the virtual address (aka paste_address) returned by mmap().

Only NX GZIP coprocessor type is supported right now and allow GZIP
engine access via /dev/crypto/nx-gzip device node.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/include/asm/vas.h              |  11 ++
 arch/powerpc/platforms/powernv/Makefile     |   2 +-
 arch/powerpc/platforms/powernv/vas-api.c    | 257 ++++++++++++++++++++++++++++
 arch/powerpc/platforms/powernv/vas-window.c |   6 +-
 arch/powerpc/platforms/powernv/vas.h        |   2 +
 5 files changed, 274 insertions(+), 4 deletions(-)
 create mode 100644 arch/powerpc/platforms/powernv/vas-api.c

diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
index f93e6b0..e064953 100644
--- a/arch/powerpc/include/asm/vas.h
+++ b/arch/powerpc/include/asm/vas.h
@@ -163,4 +163,15 @@ struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
  */
 int vas_paste_crb(struct vas_window *win, int offset, bool re);
 
+/*
+ * Register / unregister coprocessor type to VAS API which will be exported
+ * to user space. Applications can use this API to open / close window
+ * which can be used to send / receive requests directly to cooprcessor.
+ *
+ * Only NX GZIP coprocessor type is supported now, but this API can be
+ * used for others in future.
+ */
+int vas_register_coproc_api(struct module *mod);
+void vas_unregister_coproc_api(void);
+
 #endif /* __ASM_POWERPC_VAS_H */
diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile
index 395789f..fe3f0fb 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -17,7 +17,7 @@ obj-$(CONFIG_MEMORY_FAILURE)	+= opal-memory-errors.o
 obj-$(CONFIG_OPAL_PRD)	+= opal-prd.o
 obj-$(CONFIG_PERF_EVENTS) += opal-imc.o
 obj-$(CONFIG_PPC_MEMTRACE)	+= memtrace.o
-obj-$(CONFIG_PPC_VAS)	+= vas.o vas-window.o vas-debug.o vas-fault.o
+obj-$(CONFIG_PPC_VAS)	+= vas.o vas-window.o vas-debug.o vas-fault.o vas-api.o
 obj-$(CONFIG_OCXL_BASE)	+= ocxl.o
 obj-$(CONFIG_SCOM_DEBUGFS) += opal-xscom.o
 obj-$(CONFIG_PPC_SECURE_BOOT) += opal-secvar.o
diff --git a/arch/powerpc/platforms/powernv/vas-api.c b/arch/powerpc/platforms/powernv/vas-api.c
new file mode 100644
index 0000000..7d049af
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-api.c
@@ -0,0 +1,257 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * VAS user space API for its accelerators (Only NX-GZIP is supported now)
+ * Copyright (C) 2019 Haren Myneni, IBM Corp
+ */
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/cdev.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <asm/vas.h>
+#include <uapi/asm/vas-api.h>
+#include "vas.h"
+
+/*
+ * The driver creates the device node that can be used as follows:
+ * For NX-GZIP
+ *
+ *	fd = open("/dev/crypto/nx-gzip", O_RDWR);
+ *	rc = ioctl(fd, VAS_TX_WIN_OPEN, &attr);
+ *	paste_addr = mmap(NULL, PAGE_SIZE, prot, MAP_SHARED, fd, 0ULL).
+ *	vas_copy(&crb, 0, 1);
+ *	vas_paste(paste_addr, 0, 1);
+ *	close(fd) or exit process to close window.
+ *
+ * where "vas_copy" and "vas_paste" are defined in copy-paste.h.
+ * copy/paste returns to the user space directly. So refer NX hardware
+ * documententation for exact copy/paste usage and completion / error
+ * conditions.
+ */
+
+static char	*coproc_dev_name = "nx-gzip";
+
+/*
+ * Wrapper object for the nx-gzip device - there is just one instance of
+ * this node for the whole system.
+ */
+static struct coproc_dev {
+	struct cdev cdev;
+	struct device *device;
+	char *name;
+	dev_t devt;
+	struct class *class;
+} coproc_device;
+
+static char *coproc_devnode(struct device *dev, umode_t *mode)
+{
+	return kasprintf(GFP_KERNEL, "crypto/%s", dev_name(dev));
+}
+
+static int coproc_open(struct inode *inode, struct file *fp)
+{
+	/*
+	 * vas_window is allocated and assigned to fp->private_data
+	 * in ioctl. Nothing to do here for NX GZIP.
+	 */
+	return 0;
+}
+
+static int coproc_ioc_tx_win_open(struct file *fp, unsigned long arg)
+{
+	void __user *uptr = (void __user *)arg;
+	struct vas_tx_win_attr txattr = {};
+	struct vas_tx_win_open_attr uattr;
+	struct vas_window *txwin;
+	int rc, vasid;
+
+	/*
+	 * One window for file descriptor
+	 */
+	if (fp->private_data)
+		return -EEXIST;
+
+	rc = copy_from_user(&uattr, uptr, sizeof(uattr));
+	if (rc) {
+		pr_err("%s(): copy_from_user() returns %d\n", __func__, rc);
+		return -EFAULT;
+	}
+
+	if (uattr.version != 1) {
+		pr_err("Invalid version\n");
+		return -EINVAL;
+	}
+
+	vasid = uattr.vas_id;
+
+	vas_init_tx_win_attr(&txattr, VAS_COP_TYPE_GZIP);
+
+	txattr.lpid = mfspr(SPRN_LPID);
+	txattr.pidr = mfspr(SPRN_PID);
+	txattr.user_win = true;
+	txattr.rsvd_txbuf_count = false;
+	txattr.pswid = false;
+
+	pr_devel("Pid %d: Opening txwin, PIDR %ld\n", txattr.pidr,
+				mfspr(SPRN_PID));
+
+	txwin = vas_tx_win_open(vasid, VAS_COP_TYPE_GZIP, &txattr);
+	if (IS_ERR(txwin)) {
+		pr_err("%s() vas_tx_win_open() failed, %ld\n", __func__,
+					PTR_ERR(txwin));
+		return PTR_ERR(txwin);
+	}
+
+	fp->private_data = txwin;
+
+	return 0;
+}
+
+static int coproc_release(struct inode *inode, struct file *fp)
+{
+	struct vas_window *txwin = fp->private_data;
+
+	if (txwin) {
+		vas_win_close(txwin);
+		fp->private_data = NULL;
+	}
+
+	/*
+	 * We don't know here if user has other receive windows
+	 * open, so we can't really call clear_thread_tidr().
+	 * So, once the process calls set_thread_tidr(), the
+	 * TIDR value sticks around until process exits, resulting
+	 * in an extra copy in restore_sprs().
+	 */
+
+	return 0;
+}
+
+static int coproc_mmap(struct file *fp, struct vm_area_struct *vma)
+{
+	struct vas_window *txwin = fp->private_data;
+	unsigned long pfn;
+	u64 paste_addr;
+	pgprot_t prot;
+	int rc;
+
+	if ((vma->vm_end - vma->vm_start) > PAGE_SIZE) {
+		pr_debug("%s(): size 0x%zx, PAGE_SIZE 0x%zx\n", __func__,
+				(vma->vm_end - vma->vm_start), PAGE_SIZE);
+		return -EINVAL;
+	}
+
+	/* Ensure instance has an open send window */
+	if (!txwin) {
+		pr_err("%s(): No send window open?\n", __func__);
+		return -EINVAL;
+	}
+
+	vas_win_paste_addr(txwin, &paste_addr, NULL);
+	pfn = paste_addr >> PAGE_SHIFT;
+
+	/* flags, page_prot from cxl_mmap(), except we want cachable */
+	vma->vm_flags |= VM_IO | VM_PFNMAP;
+	vma->vm_page_prot = pgprot_cached(vma->vm_page_prot);
+
+	prot = __pgprot(pgprot_val(vma->vm_page_prot) | _PAGE_DIRTY);
+
+	rc = remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
+			vma->vm_end - vma->vm_start, prot);
+
+	pr_devel("%s(): paste addr %llx at %lx, rc %d\n", __func__,
+			paste_addr, vma->vm_start, rc);
+
+	return rc;
+}
+
+static long coproc_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
+{
+	switch (cmd) {
+	case VAS_TX_WIN_OPEN:
+		return coproc_ioc_tx_win_open(fp, arg);
+	default:
+		return -EINVAL;
+	}
+}
+
+static struct file_operations coproc_fops = {
+	.open = coproc_open,
+	.release = coproc_release,
+	.mmap = coproc_mmap,
+	.unlocked_ioctl = coproc_ioctl,
+};
+
+/*
+ * Supporting only nx-gzip coprocessor type now, but this API code
+ * extended to other coprocessor types later.
+ */
+int vas_register_coproc_api(struct module *mod)
+{
+	int rc = -EINVAL;
+	dev_t devno;
+
+	rc = alloc_chrdev_region(&coproc_device.devt, 1, 1, coproc_dev_name);
+	if (rc) {
+		pr_err("Unable to allocate coproc major number: %i\n", rc);
+		return rc;
+	}
+
+	pr_devel("%s device allocated, dev [%i,%i]\n", coproc_dev_name,
+			MAJOR(coproc_device.devt), MINOR(coproc_device.devt));
+
+	coproc_device.class = class_create(mod, coproc_dev_name);
+	if (IS_ERR(coproc_device.class)) {
+		rc = PTR_ERR(coproc_device.class);
+		pr_err("Unable to create %s class %d\n", coproc_dev_name, rc);
+		goto err_class;
+	}
+	coproc_device.class->devnode = coproc_devnode;
+
+	coproc_fops.owner = mod;
+	cdev_init(&coproc_device.cdev, &coproc_fops);
+
+	devno = MKDEV(MAJOR(coproc_device.devt), 0);
+	rc = cdev_add(&coproc_device.cdev, devno, 1);
+	if (rc) {
+		pr_err("cdev_add() failed %d\n", rc);
+		goto err_cdev;
+	}
+
+	coproc_device.device = device_create(coproc_device.class, NULL,
+			devno, NULL, coproc_dev_name, MINOR(devno));
+	if (IS_ERR(coproc_device.device)) {
+		rc = PTR_ERR(coproc_device.device);
+		pr_err("Unable to create coproc-%d %d\n", MINOR(devno), rc);
+		goto err;
+	}
+
+	pr_devel("%s: Added dev [%d,%d]\n", __func__, MAJOR(devno),
+			MINOR(devno));
+
+	return 0;
+
+err:
+	cdev_del(&coproc_device.cdev);
+err_cdev:
+	class_destroy(coproc_device.class);
+err_class:
+	unregister_chrdev_region(coproc_device.devt, 1);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(vas_register_coproc_api);
+
+void vas_unregister_coproc_api(void)
+{
+	dev_t devno;
+
+	cdev_del(&coproc_device.cdev);
+	devno = MKDEV(MAJOR(coproc_device.devt), 0);
+	device_destroy(coproc_device.class, devno);
+
+	class_destroy(coproc_device.class);
+	unregister_chrdev_region(coproc_device.devt, 1);
+}
+EXPORT_SYMBOL_GPL(vas_unregister_coproc_api);
diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index d239c4b..4c11475c 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -26,7 +26,7 @@
  * Compute the paste address region for the window @window using the
  * ->paste_base_addr and ->paste_win_id_shift we got from device tree.
  */
-static void compute_paste_address(struct vas_window *window, u64 *addr, int *len)
+void vas_win_paste_addr(struct vas_window *window, u64 *addr, int *len)
 {
 	int winid;
 	u64 base, shift;
@@ -80,7 +80,7 @@ static void *map_paste_region(struct vas_window *txwin)
 		goto free_name;
 
 	txwin->paste_addr_name = name;
-	compute_paste_address(txwin, &start, &len);
+	vas_win_paste_addr(txwin, &start, &len);
 
 	if (!request_mem_region(start, len, name)) {
 		pr_devel("%s(): request_mem_region(0x%llx, %d) failed\n",
@@ -138,7 +138,7 @@ static void unmap_paste_region(struct vas_window *window)
 	u64 busaddr_start;
 
 	if (window->paste_kaddr) {
-		compute_paste_address(window, &busaddr_start, &len);
+		vas_win_paste_addr(window, &busaddr_start, &len);
 		unmap_region(window->paste_kaddr, busaddr_start, len);
 		window->paste_kaddr = NULL;
 		kfree(window->paste_addr_name);
diff --git a/arch/powerpc/platforms/powernv/vas.h b/arch/powerpc/platforms/powernv/vas.h
index 32b5261..c3b4f7e 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -437,6 +437,8 @@ struct vas_winctx {
 extern void vas_return_credit(struct vas_window *window, bool tx);
 extern struct vas_window *vas_pswid_to_window(struct vas_instance *vinst,
 						uint32_t pswid);
+extern void vas_win_paste_addr(struct vas_window *window, u64 *addr,
+					int *len);
 
 static inline int vas_window_pid(struct vas_window *window)
 {
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v5 2/9] powerpc/vas: Define VAS_TX_WIN_OPEN ioctl API
From: Haren Myneni @ 2020-04-01 21:58 UTC (permalink / raw)
  To: mpe; +Cc: mikey, herbert, npiggin, linux-crypto, sukadev, linuxppc-dev, dja
In-Reply-To: <1585777592.10664.462.camel@hbabu-laptop>


Define the VAS_TX_WIN_OPEN ioctl interface for NX GZIP access
from user space. This interface is used to open GZIP send window and
mmap region which can be used by user space to send requests to NX
directly with copy/paste instructions.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 Documentation/userspace-api/ioctl/ioctl-number.rst |  1 +
 arch/powerpc/include/uapi/asm/vas-api.h            | 22 ++++++++++++++++++++++
 2 files changed, 23 insertions(+)
 create mode 100644 arch/powerpc/include/uapi/asm/vas-api.h

diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
index f759eda..f18accb 100644
--- a/Documentation/userspace-api/ioctl/ioctl-number.rst
+++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
@@ -286,6 +286,7 @@ Code  Seq#    Include File                                           Comments
 'v'   00-1F  linux/fs.h                                              conflict!
 'v'   00-0F  linux/sonypi.h                                          conflict!
 'v'   00-0F  media/v4l2-subdev.h                                     conflict!
+'v'   20-27  arch/powerpc/include/uapi/asm/vas-api.h		     VAS API
 'v'   C0-FF  linux/meye.h                                            conflict!
 'w'   all                                                            CERN SCI driver
 'y'   00-1F                                                          packet based user level communications
diff --git a/arch/powerpc/include/uapi/asm/vas-api.h b/arch/powerpc/include/uapi/asm/vas-api.h
new file mode 100644
index 0000000..fe95d67
--- /dev/null
+++ b/arch/powerpc/include/uapi/asm/vas-api.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ * Copyright 2019 IBM Corp.
+ */
+
+#ifndef _UAPI_MISC_VAS_H
+#define _UAPI_MISC_VAS_H
+
+#include <asm/ioctl.h>
+
+#define VAS_MAGIC	'v'
+#define VAS_TX_WIN_OPEN	_IOW(VAS_MAGIC, 0x20, struct vas_tx_win_open_attr)
+
+struct vas_tx_win_open_attr {
+	__u32	version;
+	__s16	vas_id;	/* specific instance of vas or -1 for default */
+	__u16	reserved1;
+	__u64	flags;	/* Future use */
+	__u64	reserved2[6];
+};
+
+#endif /* _UAPI_MISC_VAS_H */
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v5 1/9] powerpc/vas: Initialize window attributes for GZIP coprocessor type
From: Haren Myneni @ 2020-04-01 21:57 UTC (permalink / raw)
  To: mpe; +Cc: mikey, herbert, npiggin, linux-crypto, sukadev, linuxppc-dev, dja
In-Reply-To: <1585777592.10664.462.camel@hbabu-laptop>


Initialize send and receive window attributes for GZIP high and
normal priority types.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index be900ad..d239c4b 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -817,7 +817,8 @@ void vas_init_rx_win_attr(struct vas_rx_win_attr *rxattr, enum vas_cop_type cop)
 {
 	memset(rxattr, 0, sizeof(*rxattr));
 
-	if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI) {
+	if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI ||
+		cop == VAS_COP_TYPE_GZIP || cop == VAS_COP_TYPE_GZIP_HIPRI) {
 		rxattr->pin_win = true;
 		rxattr->nx_win = true;
 		rxattr->fault_win = false;
@@ -892,7 +893,8 @@ void vas_init_tx_win_attr(struct vas_tx_win_attr *txattr, enum vas_cop_type cop)
 {
 	memset(txattr, 0, sizeof(*txattr));
 
-	if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI) {
+	if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI ||
+		cop == VAS_COP_TYPE_GZIP || cop == VAS_COP_TYPE_GZIP_HIPRI) {
 		txattr->rej_no_credit = false;
 		txattr->rx_wcred_mode = true;
 		txattr->tx_wcred_mode = true;
@@ -976,9 +978,14 @@ static bool tx_win_args_valid(enum vas_cop_type cop,
 	if (attr->wcreds_max > VAS_TX_WCREDS_MAX)
 		return false;
 
-	if (attr->user_win &&
-			(cop != VAS_COP_TYPE_FTW || attr->rsvd_txbuf_count))
-		return false;
+	if (attr->user_win) {
+		if (attr->rsvd_txbuf_count)
+			return false;
+
+		if (cop != VAS_COP_TYPE_FTW && cop != VAS_COP_TYPE_GZIP &&
+			cop != VAS_COP_TYPE_GZIP_HIPRI)
+			return false;
+	}
 
 	return true;
 }
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v5 0/9] crypto/nx: Enable GZIP engine and provide userpace API
From: Haren Myneni @ 2020-04-01 21:46 UTC (permalink / raw)
  To: mpe, herbert; +Cc: mikey, npiggin, linux-crypto, sukadev, linuxppc-dev, dja


Power9 processor supports Virtual Accelerator Switchboard (VAS) which
allows kernel and userspace to send compression requests to Nest
Accelerator (NX) directly. The NX unit comprises of 2 842 compression
engines and 1 GZIP engine. Linux kernel already has 842 compression
support on kernel. This patch series adds GZIP compression support
from user space. The GZIP Compression engine implements the ZLIB and
GZIP compression algorithms. No plans of adding NX-GZIP compression
support in kernel right now.

Applications can send requests to NX directly with COPY/PASTE
instructions. But kernel has to establish channel / window on NX-GZIP
device for the userspace. So userspace access to the GZIP engine is
provided through /dev/crypto/nx-gzip device with several operations.

An application must open the this device to obtain a file descriptor (fd).
Using the fd, application should issue the VAS_TX_WIN_OPEN ioctl to
establish a connection to the engine. Once window is opened, should use
mmap() system call to map the hardware address of engine's request queue
into the application's virtual address space. Then user space forms the
request as co-processor Request Block (CRB) and paste this CRB on the
mapped HW address using COPY/PASTE instructions. Application can poll
on status flags (part of CRB) with timeout for request completion.

For VAS_TX_WIN_OPEN ioctl, if user space passes vas_id = -1 (struct
vas_tx_win_open_attr), kernel determines the VAS instance on the
corresponding chip based on the CPU on which the process is executing.
Otherwise, the specified VAS instance is used if application passes the
proper VAS instance (vas_id listed in /proc/device-tree/vas@*/ibm,vas_id).

Process can open multiple windows with different FDs or can send several
requests to NX on the same window at the same time.

A userspace library libnxz is available:
        https://github.com/abalib/power-gzip

Applications that use inflate/deflate calls can link with libNXz and use
NX GZIP compression without any modification.

Tested the available 842 compression on power8 and power9 system to make
sure no regression and tested GZIP compression on power9 with tests
available in the above link.

Thanks to Bulent Abali for nxz library and tests development.

Changelog:

V2:
  - Move user space API code to powerpc as suggested. Also this API
    can be extended to any other coprocessor type that VAS can support
    in future. Example: Fast thread wakeup feature from VAS
  - Rebased to 5.6-rc3

V3:
  - Fix sparse warnings (patches 3&6)

V4:
  - Remove unused coproc_instid and add only window address in
    fp->private_data.
  - Add NX User's manual and Copy/paste links in VAS API documentation
    in patch and other changes as Daniel Axtens suggested

V5:
  - Added "NX Fault handling" section in VAS API documentation as Nick
    suggested.
  - Dcoumentation: mmap size should be PAGE_SIZE as Daniel Axtens pointed.

Haren Myneni (9):
  powerpc/vas: Initialize window attributes for GZIP coprocessor type
  powerpc/vas: Define VAS_TX_WIN_OPEN ioctl API
  powerpc/vas: Add VAS user space API
  crypto/nx: Initialize coproc entry with kzalloc
  crypto/nx: Rename nx-842-powernv file name to nx-common-powernv
  crypto/nx: Make enable code generic to add new GZIP compression type
  crypto/nx: Enable and setup GZIP compresstion type
  crypto/nx: Remove 'pid' in vas_tx_win_attr struct
  Documentation/powerpc: VAS API

 Documentation/powerpc/index.rst                    |    1 +
 Documentation/powerpc/vas-api.rst                  |  292 +++++
 Documentation/userspace-api/ioctl/ioctl-number.rst |    1 +
 arch/powerpc/include/asm/vas.h                     |   12 +-
 arch/powerpc/include/uapi/asm/vas-api.h            |   22 +
 arch/powerpc/platforms/powernv/Makefile            |    2 +-
 arch/powerpc/platforms/powernv/vas-api.c           |  257 +++++
 arch/powerpc/platforms/powernv/vas-window.c        |   23 +-
 arch/powerpc/platforms/powernv/vas.h               |    2 +
 drivers/crypto/nx/Makefile                         |    2 +-
 drivers/crypto/nx/nx-842-powernv.c                 | 1062 ------------------
 drivers/crypto/nx/nx-common-powernv.c              | 1133 ++++++++++++++++++++
 12 files changed, 1736 insertions(+), 1073 deletions(-)
 create mode 100644 Documentation/powerpc/vas-api.rst
 create mode 100644 arch/powerpc/include/uapi/asm/vas-api.h
 create mode 100644 arch/powerpc/platforms/powernv/vas-api.c
 delete mode 100644 drivers/crypto/nx/nx-842-powernv.c
 create mode 100644 drivers/crypto/nx/nx-common-powernv.c

-- 
1.8.3.1




^ permalink raw reply

* [PATCH v2] sched/core: fix illegal RCU from offline CPUs
From: Qian Cai @ 2020-04-01 21:40 UTC (permalink / raw)
  To: peterz, mingo
  Cc: juri.lelli, James.Bottomley, vincent.guittot, linux-parisc,
	paulmck, deller, linux-kernel, rostedt, bsegall, linux-mm,
	Qian Cai, mgorman, tglx, linuxppc-dev, dietmar.eggemann

From: Peter Zijlstra <peterz@infradead.org>

In the CPU-offline process, it calls mmdrop() after idle entry and the
subsequent call to cpuhp_report_idle_dead(). Once execution passes the
call to rcu_report_dead(), RCU is ignoring the CPU, which results in
lockdep complaining when mmdrop() uses RCU from either memcg or
debugobjects below.

Fix it by cleaning up the active_mm state from BP instead. Every arch
which has CONFIG_HOTPLUG_CPU should have already called idle_task_exit()
from AP. The only exception is parisc because it switches them to
&init_mm unconditionally (see smp_boot_one_cpu() and smp_cpu_init()),
but the patch will still work there because it calls mmgrab(&init_mm) in
smp_cpu_init() and then should call mmdrop(&init_mm) in finish_cpu().

WARNING: suspicious RCU usage
-----------------------------
kernel/workqueue.c:710 RCU or wq_pool_mutex should be held!

other info that might help us debug this:

RCU used illegally from offline CPU!
Call Trace:
 dump_stack+0xf4/0x164 (unreliable)
 lockdep_rcu_suspicious+0x140/0x164
 get_work_pool+0x110/0x150
 __queue_work+0x1bc/0xca0
 queue_work_on+0x114/0x120
 css_release+0x9c/0xc0
 percpu_ref_put_many+0x204/0x230
 free_pcp_prepare+0x264/0x570
 free_unref_page+0x38/0xf0
 __mmdrop+0x21c/0x2c0
 idle_task_exit+0x170/0x1b0
 pnv_smp_cpu_kill_self+0x38/0x2e0
 cpu_die+0x48/0x64
 arch_cpu_idle_dead+0x30/0x50
 do_idle+0x2f4/0x470
 cpu_startup_entry+0x38/0x40
 start_secondary+0x7a8/0xa80
 start_secondary_resume+0x10/0x14

<Peter to sign off here>
Signed-off-by: Qian Cai <cai@lca.pw>
---
 arch/powerpc/platforms/powernv/smp.c |  1 -
 include/linux/sched/mm.h             |  2 ++
 kernel/cpu.c                         | 18 +++++++++++++++++-
 kernel/sched/core.c                  |  5 +++--
 4 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c
index 13e251699346..b2ba3e95bda7 100644
--- a/arch/powerpc/platforms/powernv/smp.c
+++ b/arch/powerpc/platforms/powernv/smp.c
@@ -167,7 +167,6 @@ static void pnv_smp_cpu_kill_self(void)
 	/* Standard hot unplug procedure */
 
 	idle_task_exit();
-	current->active_mm = NULL; /* for sanity */
 	cpu = smp_processor_id();
 	DBG("CPU%d offline\n", cpu);
 	generic_set_cpu_dead(cpu);
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index c49257a3b510..a132d875d351 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -49,6 +49,8 @@ static inline void mmdrop(struct mm_struct *mm)
 		__mmdrop(mm);
 }
 
+void mmdrop(struct mm_struct *mm);
+
 /*
  * This has to be called after a get_task_mm()/mmget_not_zero()
  * followed by taking the mmap_sem for writing before modifying the
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 2371292f30b0..244d30544377 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -3,6 +3,7 @@
  *
  * This code is licenced under the GPL.
  */
+#include <linux/sched/mm.h>
 #include <linux/proc_fs.h>
 #include <linux/smp.h>
 #include <linux/init.h>
@@ -564,6 +565,21 @@ static int bringup_cpu(unsigned int cpu)
 	return bringup_wait_for_ap(cpu);
 }
 
+static int finish_cpu(unsigned int cpu)
+{
+	struct task_struct *idle = idle_thread_get(cpu);
+	struct mm_struct *mm = idle->active_mm;
+
+	/*
+	 * idle_task_exit() will have switched to &init_mm, now
+	 * clean up any remaining active_mm state.
+	 */
+	if (mm != &init_mm)
+		idle->active_mm = &init_mm;
+	mmdrop(mm);
+	return 0;
+}
+
 /*
  * Hotplug state machine related functions
  */
@@ -1549,7 +1565,7 @@ static struct cpuhp_step cpuhp_hp_states[] = {
 	[CPUHP_BRINGUP_CPU] = {
 		.name			= "cpu:bringup",
 		.startup.single		= bringup_cpu,
-		.teardown.single	= NULL,
+		.teardown.single	= finish_cpu,
 		.cant_stop		= true,
 	},
 	/* Final state before CPU kills itself */
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index a2694ba82874..8787958339d5 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6200,13 +6200,14 @@ void idle_task_exit(void)
 	struct mm_struct *mm = current->active_mm;
 
 	BUG_ON(cpu_online(smp_processor_id()));
+	BUG_ON(current != this_rq()->idle);
 
 	if (mm != &init_mm) {
 		switch_mm(mm, &init_mm, current);
-		current->active_mm = &init_mm;
 		finish_arch_post_lock_switch();
 	}
-	mmdrop(mm);
+
+	/* finish_cpu(), as ran on the BP, will clean up the active_mm state */
 }
 
 /*
-- 
2.21.0 (Apple Git-122.2)


^ permalink raw reply related

* Re: [PATCH v2] powerpc/pseries: Fix MCE handling on pseries
From: Ganesh @ 2020-04-01 15:45 UTC (permalink / raw)
  To: mpe, linuxppc-dev; +Cc: mahesh, npiggin
In-Reply-To: <20200320110119.10207-1-ganeshgr@linux.ibm.com>

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On 3/20/20 4:31 PM, Ganesh Goudar wrote:

> MCE handling on pSeries platform fails as recent rework to use common
> code for pSeries and PowerNV in machine check error handling tries to
> access per-cpu variables in realmode. The per-cpu variables may be
> outside the RMO region on pSeries platform and needs translation to be
> enabled for access. Just moving these per-cpu variable into RMO region
> did'nt help because we queue some work to workqueues in real mode, which
> again tries to touch per-cpu variables. Also fwnmi_release_errinfo()
> cannot be called when translation is not enabled.
>
> This patch fixes this by enabling translation in the exception handler
> when all required real mode handling is done. This change only affects
> the pSeries platform.
>
> Without this fix below kernel crash is seen on injecting
> SLB multihit:
>
> BUG: Unable to handle kernel data access on read at 0xc00000027b205950
> Faulting instruction address: 0xc00000000003b7e0
> Oops: Kernel access of bad area, sig: 11 [#1]
> LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
> Modules linked in: mcetest_slb(OE+) af_packet(E) xt_tcpudp(E) ip6t_rpfilter(E) ip6t_REJECT(E) ipt_REJECT(E) xt_conntrack(E) ip_set(E) nfnetlink(E) ebtable_nat(E) ebtable_broute(E) ip6table_nat(E) ip6table_mangle(E) ip6table_raw(E) ip6table_security(E) iptable_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) iptable_mangle(E) iptable_raw(E) iptable_security(E) ebtable_filter(E) ebtables(E) ip6table_filter(E) ip6_tables(E) iptable_filter(E) ip_tables(E) x_tables(E) xfs(E) ibmveth(E) vmx_crypto(E) gf128mul(E) uio_pdrv_genirq(E) uio(E) crct10dif_vpmsum(E) rtc_generic(E) btrfs(E) libcrc32c(E) xor(E) zstd_decompress(E) zstd_compress(E) raid6_pq(E) sr_mod(E) sd_mod(E) cdrom(E) ibmvscsi(E) scsi_transport_srp(E) crc32c_vpmsum(E) dm_mod(E) sg(E) scsi_mod(E)
> CPU: 34 PID: 8154 Comm: insmod Kdump: loaded Tainted: G OE 5.5.0-mahesh #1
> NIP: c00000000003b7e0 LR: c0000000000f2218 CTR: 0000000000000000
> REGS: c000000007dcb960 TRAP: 0300 Tainted: G OE (5.5.0-mahesh)
> MSR: 8000000000001003 <SF,ME,RI,LE> CR: 28002428 XER: 20040000
> CFAR: c0000000000f2214 DAR: c00000027b205950 DSISR: 40000000 IRQMASK: 0
> GPR00: c0000000000f2218 c000000007dcbbf0 c000000001544800 c000000007dcbd70
> GPR04: 0000000000000001 c000000007dcbc98 c008000000d00258 c0080000011c0000
> GPR08: 0000000000000000 0000000300000003 c000000001035950 0000000003000048
> GPR12: 000000027a1d0000 c000000007f9c000 0000000000000558 0000000000000000
> GPR16: 0000000000000540 c008000001110000 c008000001110540 0000000000000000
> GPR20: c00000000022af10 c00000025480fd70 c008000001280000 c00000004bfbb300
> GPR24: c000000001442330 c00800000800000d c008000008000000 4009287a77000510
> GPR28: 0000000000000000 0000000000000002 c000000001033d30 0000000000000001
> NIP [c00000000003b7e0] save_mce_event+0x30/0x240
> LR [c0000000000f2218] pseries_machine_check_realmode+0x2c8/0x4f0
> Call Trace:
> Instruction dump:
> 3c4c0151 38429050 7c0802a6 60000000 fbc1fff0 fbe1fff8 f821ffd1 3d42ffaf
> 3fc2ffaf e98d0030 394a1150 3bdef530 <7d6a62aa> 1d2b0048 2f8b0063 380b0001
> ---[ end trace 46fd63f36bbdd940 ]---
>
> Fixes: 9ca766f9891d ("powerpc/64s/pseries: machine check convert to use common event code")
> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
> Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
> Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>

Hi mpe, Do you have any comments on this patch ?


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^ permalink raw reply

* [PATCH v9 13/13] powerpc/vas: Free send window in VAS instance after credits returned
From: Haren Myneni @ 2020-04-01 21:32 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


NX may be processing requests while trying to close window. Wait until
all credits are returned and then free send window from VAS instance.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index c8644c3..be900ad 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1317,14 +1317,14 @@ int vas_win_close(struct vas_window *window)
 
 	unmap_paste_region(window);
 
-	clear_vinst_win(window);
-
 	poll_window_busy_state(window);
 
 	unpin_close_window(window);
 
 	poll_window_credits(window);
 
+	clear_vinst_win(window);
+
 	poll_window_castout(window);
 
 	/* if send window, drop reference to matching receive window */
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v9 12/13] powerpc/vas: Display process stuck message
From: Haren Myneni @ 2020-04-01 21:31 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


Process can not close send window until all requests are processed.
Means wait until window state is not busy and send credits are
returned. Display debug messages in case taking longer to close the
window.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index 084e76b..c8644c3 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1182,6 +1182,7 @@ static void poll_window_credits(struct vas_window *window)
 {
 	u64 val;
 	int creds, mode;
+	int count = 0;
 
 	val = read_hvwc_reg(window, VREG(WINCTL));
 	if (window->tx_win)
@@ -1200,10 +1201,27 @@ static void poll_window_credits(struct vas_window *window)
 		creds = GET_FIELD(VAS_LRX_WCRED, val);
 	}
 
+	/*
+	 * Takes around few milliseconds to complete all pending requests
+	 * and return credits.
+	 * TODO: Scan fault FIFO and invalidate CRBs points to this window
+	 *       and issue CRB Kill to stop all pending requests. Need only
+	 *       if there is a bug in NX or fault handling in kernel.
+	 */
 	if (creds < window->wcreds_max) {
 		val = 0;
 		set_current_state(TASK_UNINTERRUPTIBLE);
 		schedule_timeout(msecs_to_jiffies(10));
+		count++;
+		/*
+		 * Process can not close send window until all credits are
+		 * returned.
+		 */
+		if (!(count % 10000))
+			pr_debug("VAS: pid %d stuck. Waiting for credits returned for Window(%d). creds %d, Retries %d\n",
+				vas_window_pid(window), window->winid,
+				creds, count);
+
 		goto retry;
 	}
 }
@@ -1217,6 +1235,7 @@ static void poll_window_busy_state(struct vas_window *window)
 {
 	int busy;
 	u64 val;
+	int count = 0;
 
 retry:
 	val = read_hvwc_reg(window, VREG(WIN_STATUS));
@@ -1225,6 +1244,15 @@ static void poll_window_busy_state(struct vas_window *window)
 		val = 0;
 		set_current_state(TASK_UNINTERRUPTIBLE);
 		schedule_timeout(msecs_to_jiffies(5));
+		count++;
+		/*
+		 * Takes around few milliseconds to process all pending
+		 * requests.
+		 */
+		if (!(count % 10000))
+			pr_debug("VAS: pid %d stuck. Window (ID=%d) is in busy state. Retries %d\n",
+				vas_window_pid(window), window->winid, count);
+
 		goto retry;
 	}
 }
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v9 11/13] powerpc/vas: Do not use default credits for receive window
From: Haren Myneni @ 2020-04-01 21:31 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


System checkstops if RxFIFO overruns with more requests than the
maximum possible number of CRBs allowed in FIFO at any time. So
max credits value (rxattr.wcreds_max) is set and is passed to
vas_rx_win_open() by the the driver.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 4 ++--
 arch/powerpc/platforms/powernv/vas.h        | 2 --
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index 33aaa7a..084e76b 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -772,7 +772,7 @@ static bool rx_win_args_valid(enum vas_cop_type cop,
 	if (attr->rx_fifo_size > VAS_RX_FIFO_SIZE_MAX)
 		return false;
 
-	if (attr->wcreds_max > VAS_RX_WCREDS_MAX)
+	if (!attr->wcreds_max)
 		return false;
 
 	if (attr->nx_win) {
@@ -877,7 +877,7 @@ struct vas_window *vas_rx_win_open(int vasid, enum vas_cop_type cop,
 	rxwin->nx_win = rxattr->nx_win;
 	rxwin->user_win = rxattr->user_win;
 	rxwin->cop = cop;
-	rxwin->wcreds_max = rxattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
+	rxwin->wcreds_max = rxattr->wcreds_max;
 
 	init_winctx_for_rxwin(rxwin, rxattr, &winctx);
 	init_winctx_regs(rxwin, &winctx);
diff --git a/arch/powerpc/platforms/powernv/vas.h b/arch/powerpc/platforms/powernv/vas.h
index efdaa28..32b5261 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -101,11 +101,9 @@
 /*
  * Initial per-process credits.
  * Max send window credits:    4K-1 (12-bits in VAS_TX_WCRED)
- * Max receive window credits: 64K-1 (16 bits in VAS_LRX_WCRED)
  *
  * TODO: Needs tuning for per-process credits
  */
-#define VAS_RX_WCREDS_MAX		((64 << 10) - 1)
 #define VAS_TX_WCREDS_MAX		((4 << 10) - 1)
 #define VAS_WCREDS_DEFAULT		(1 << 10)
 
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v9 10/13] powerpc/vas: Print CRB and FIFO values
From: Haren Myneni @ 2020-04-01 21:30 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


Dump FIFO entries if could not find send window and print CRB
for debugging.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-fault.c | 41 ++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/vas-fault.c b/arch/powerpc/platforms/powernv/vas-fault.c
index b6bec64..25db70b 100644
--- a/arch/powerpc/platforms/powernv/vas-fault.c
+++ b/arch/powerpc/platforms/powernv/vas-fault.c
@@ -26,6 +26,28 @@
  */
 #define VAS_FAULT_WIN_FIFO_SIZE	(4 << 20)
 
+static void dump_crb(struct coprocessor_request_block *crb)
+{
+	struct data_descriptor_entry *dde;
+	struct nx_fault_stamp *nx;
+
+	dde = &crb->source;
+	pr_devel("SrcDDE: addr 0x%llx, len %d, count %d, idx %d, flags %d\n",
+		be64_to_cpu(dde->address), be32_to_cpu(dde->length),
+		dde->count, dde->index, dde->flags);
+
+	dde = &crb->target;
+	pr_devel("TgtDDE: addr 0x%llx, len %d, count %d, idx %d, flags %d\n",
+		be64_to_cpu(dde->address), be32_to_cpu(dde->length),
+		dde->count, dde->index, dde->flags);
+
+	nx = &crb->stamp.nx;
+	pr_devel("NX Stamp: PSWID 0x%x, FSA 0x%llx, flags 0x%x, FS 0x%x\n",
+		be32_to_cpu(nx->pswid),
+		be64_to_cpu(crb->stamp.nx.fault_storage_addr),
+		nx->flags, nx->fault_status);
+}
+
 /*
  * Update the CSB to indicate a translation error.
  *
@@ -148,6 +170,23 @@ static void update_csb(struct vas_window *window,
 			pid_vnr(pid), rc);
 }
 
+static void dump_fifo(struct vas_instance *vinst, void *entry)
+{
+	unsigned long *end = vinst->fault_fifo + vinst->fault_fifo_size;
+	unsigned long *fifo = entry;
+	int i;
+
+	pr_err("Fault fifo size %d, Max crbs %d\n", vinst->fault_fifo_size,
+			vinst->fault_fifo_size / CRB_SIZE);
+
+	/* Dump 10 CRB entries or until end of FIFO */
+	pr_err("Fault FIFO Dump:\n");
+	for (i = 0; i < 10*(CRB_SIZE/8) && fifo < end; i += 4, fifo += 4) {
+		pr_err("[%.3d, %p]: 0x%.16lx 0x%.16lx 0x%.16lx 0x%.16lx\n",
+			i, fifo, *fifo, *(fifo+1), *(fifo+2), *(fifo+3));
+	}
+}
+
 /*
  * Process valid CRBs in fault FIFO.
  * NX process user space requests, return credit and update the status
@@ -233,6 +272,7 @@ irqreturn_t vas_fault_thread_fn(int irq, void *data)
 				vinst->vas_id, vinst->fault_fifo, fifo,
 				vinst->fault_crbs);
 
+		dump_crb(crb);
 		window = vas_pswid_to_window(vinst,
 				be32_to_cpu(crb->stamp.nx.pswid));
 
@@ -245,6 +285,7 @@ irqreturn_t vas_fault_thread_fn(int irq, void *data)
 			 * But we should not get here.
 			 * TODO: Disable IRQ.
 			 */
+			dump_fifo(vinst, (void *)entry);
 			pr_err("VAS[%d] fault_fifo %p, fifo %p, pswid 0x%x, fault_crbs %d bad CRB?\n",
 				vinst->vas_id, vinst->fault_fifo, fifo,
 				be32_to_cpu(crb->stamp.nx.pswid),
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v9 09/13] powerpc/vas: Return credits after handling fault
From: Haren Myneni @ 2020-04-01 21:29 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


NX uses credit mechanism to control the number of requests issued on
a specific window at any point of time. Only send windows and fault
window are used credits. When the request is issued on a given window,
a credit is taken. This credit will be returned after that request is
processed. If credits are not available, returns RMA_Busy for send
window and RMA_Reject for fault window.

NX expects OS to return credit for send window after processing fault
CRB. Also credit has to be returned for fault window after handling
the fault.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-fault.c  |  9 ++++++++
 arch/powerpc/platforms/powernv/vas-window.c | 36 +++++++++++++++++++++++++++++
 arch/powerpc/platforms/powernv/vas.h        |  1 +
 3 files changed, 46 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/vas-fault.c b/arch/powerpc/platforms/powernv/vas-fault.c
index 354577d..b6bec64 100644
--- a/arch/powerpc/platforms/powernv/vas-fault.c
+++ b/arch/powerpc/platforms/powernv/vas-fault.c
@@ -224,6 +224,10 @@ irqreturn_t vas_fault_thread_fn(int irq, void *data)
 		memcpy(crb, fifo, CRB_SIZE);
 		entry->stamp.nx.pswid = cpu_to_be32(FIFO_INVALID_ENTRY);
 		entry->ccw |= cpu_to_be32(CCW0_INVALID);
+		/*
+		 * Return credit for the fault window.
+		 */
+		vas_return_credit(vinst->fault_win, false);
 
 		pr_devel("VAS[%d] fault_fifo %p, fifo %p, fault_crbs %d\n",
 				vinst->vas_id, vinst->fault_fifo, fifo,
@@ -249,6 +253,11 @@ irqreturn_t vas_fault_thread_fn(int irq, void *data)
 			WARN_ON_ONCE(1);
 		} else {
 			update_csb(window, crb);
+			/*
+			 * Return credit for send window after processing
+			 * fault CRB.
+			 */
+			vas_return_credit(window, true);
 		}
 	}
 }
diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index 382fe25..33aaa7a 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1318,6 +1318,42 @@ int vas_win_close(struct vas_window *window)
 }
 EXPORT_SYMBOL_GPL(vas_win_close);
 
+/*
+ * Return credit for the given window.
+ * Send windows and fault window uses credit mechanism as follows:
+ *
+ * Send windows:
+ * - The default number of credits available for each send window is
+ *   1024. It means 1024 requests can be issued asynchronously at the
+ *   same time. If the credit is not available, that request will be
+ *   returned with RMA_Busy.
+ * - One credit is taken when NX request is issued.
+ * - This credit is returned after NX processed that request.
+ * - If NX encounters translation error, kernel will return the
+ *   credit on the specific send window after processing the fault CRB.
+ *
+ * Fault window:
+ * - The total number credits available is FIFO_SIZE/CRB_SIZE.
+ *   Means 4MB/128 in the current implementation. If credit is not
+ *   available, RMA_Reject is returned.
+ * - A credit is taken when NX pastes CRB in fault FIFO.
+ * - The kernel with return credit on fault window after reading entry
+ *   from fault FIFO.
+ */
+void vas_return_credit(struct vas_window *window, bool tx)
+{
+	uint64_t val;
+
+	val = 0ULL;
+	if (tx) { /* send window */
+		val = SET_FIELD(VAS_TX_WCRED, val, 1);
+		write_hvwc_reg(window, VREG(TX_WCRED_ADDER), val);
+	} else {
+		val = SET_FIELD(VAS_LRX_WCRED, val, 1);
+		write_hvwc_reg(window, VREG(LRX_WCRED_ADDER), val);
+	}
+}
+
 struct vas_window *vas_pswid_to_window(struct vas_instance *vinst,
 		uint32_t pswid)
 {
diff --git a/arch/powerpc/platforms/powernv/vas.h b/arch/powerpc/platforms/powernv/vas.h
index 0af7912..efdaa28 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -436,6 +436,7 @@ struct vas_winctx {
 extern int vas_setup_fault_window(struct vas_instance *vinst);
 extern irqreturn_t vas_fault_thread_fn(int irq, void *data);
 extern irqreturn_t vas_fault_handler(int irq, void *dev_id);
+extern void vas_return_credit(struct vas_window *window, bool tx);
 extern struct vas_window *vas_pswid_to_window(struct vas_instance *vinst,
 						uint32_t pswid);
 
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v9 08/13] powerpc/vas: Update CSB and notify process for fault CRBs
From: Haren Myneni @ 2020-04-01 21:29 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


Applications polls on CSB for the status update after requests are
issued. NX process these requests and update the CSB with the status.
If it encounters translation error, pastes CRB in fault FIFO and
raises an interrupt. The kernel handles fault by reading CRB from
fault FIFO and process the fault CRB.

For each fault CRB, update fault address in CRB (fault_storage_addr)
and translation error status in CSB so that user space can touch the
fault address and resend the request. If the user space passed invalid
CSB address send signal to process with SIGSEGV.

In the case of multi-thread applications, child thread may not be
available. So if the task is not running, send signal to tgid.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-fault.c | 126 ++++++++++++++++++++++++++++-
 1 file changed, 125 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/vas-fault.c b/arch/powerpc/platforms/powernv/vas-fault.c
index 0da8358..354577d 100644
--- a/arch/powerpc/platforms/powernv/vas-fault.c
+++ b/arch/powerpc/platforms/powernv/vas-fault.c
@@ -11,6 +11,7 @@
 #include <linux/slab.h>
 #include <linux/uaccess.h>
 #include <linux/kthread.h>
+#include <linux/sched/signal.h>
 #include <linux/mmu_context.h>
 #include <asm/icswx.h>
 
@@ -26,6 +27,128 @@
 #define VAS_FAULT_WIN_FIFO_SIZE	(4 << 20)
 
 /*
+ * Update the CSB to indicate a translation error.
+ *
+ * User space will be polling on CSB after the request is issued.
+ * If NX can handle the request without any issues, it updates CSB.
+ * Whereas if NX encounters page fault, the kernel will handle the
+ * fault and update CSB with translation error.
+ *
+ * If we are unable to update the CSB means copy_to_user failed due to
+ * invalid csb_addr, send a signal to the process.
+ */
+static void update_csb(struct vas_window *window,
+			struct coprocessor_request_block *crb)
+{
+	struct coprocessor_status_block csb;
+	struct kernel_siginfo info;
+	struct task_struct *tsk;
+	void __user *csb_addr;
+	struct pid *pid;
+	int rc;
+
+	/*
+	 * NX user space windows can not be opened for task->mm=NULL
+	 * and faults will not be generated for kernel requests.
+	 */
+	if (WARN_ON_ONCE(!window->mm || !window->user_win))
+		return;
+
+	csb_addr = (void __user *)be64_to_cpu(crb->csb_addr);
+
+	memset(&csb, 0, sizeof(csb));
+	csb.cc = CSB_CC_TRANSLATION;
+	csb.ce = CSB_CE_TERMINATION;
+	csb.cs = 0;
+	csb.count = 0;
+
+	/*
+	 * NX operates and returns in BE format as defined CRB struct.
+	 * So saves fault_storage_addr in BE as NX pastes in FIFO and
+	 * expects user space to convert to CPU format.
+	 */
+	csb.address = crb->stamp.nx.fault_storage_addr;
+	csb.flags = 0;
+
+	pid = window->pid;
+	tsk = get_pid_task(pid, PIDTYPE_PID);
+	/*
+	 * Process closes send window after all pending NX requests are
+	 * completed. In multi-thread applications, a child thread can
+	 * open a window and can exit without closing it. May be some
+	 * requests are pending or this window can be used by other
+	 * threads later. We should handle faults if NX encounters
+	 * pages faults on these requests. Update CSB with translation
+	 * error and fault address. If csb_addr passed by user space is
+	 * invalid, send SEGV signal to pid saved in window. If the
+	 * child thread is not running, send the signal to tgid.
+	 * Parent thread (tgid) will close this window upon its exit.
+	 *
+	 * pid and mm references are taken when window is opened by
+	 * process (pid). So tgid is used only when child thread opens
+	 * a window and exits without closing it.
+	 */
+	if (!tsk) {
+		pid = window->tgid;
+		tsk = get_pid_task(pid, PIDTYPE_PID);
+		/*
+		 * Parent thread (tgid) will be closing window when it
+		 * exits. So should not get here.
+		 */
+		if (WARN_ON_ONCE(!tsk))
+			return;
+	}
+
+	/* Return if the task is exiting. */
+	if (tsk->flags & PF_EXITING) {
+		put_task_struct(tsk);
+		return;
+	}
+
+	use_mm(window->mm);
+	rc = copy_to_user(csb_addr, &csb, sizeof(csb));
+	/*
+	 * User space polls on csb.flags (first byte). So add barrier
+	 * then copy first byte with csb flags update.
+	 */
+	if (!rc) {
+		csb.flags = CSB_V;
+		/* Make sure update to csb.flags is visible now */
+		smp_mb();
+		rc = copy_to_user(csb_addr, &csb, sizeof(u8));
+	}
+	unuse_mm(window->mm);
+	put_task_struct(tsk);
+
+	/* Success */
+	if (!rc)
+		return;
+
+	pr_debug("Invalid CSB address 0x%p signalling pid(%d)\n",
+			csb_addr, pid_vnr(pid));
+
+	clear_siginfo(&info);
+	info.si_signo = SIGSEGV;
+	info.si_errno = EFAULT;
+	info.si_code = SEGV_MAPERR;
+	info.si_addr = csb_addr;
+
+	/*
+	 * process will be polling on csb.flags after request is sent to
+	 * NX. So generally CSB update should not fail except when an
+	 * application passes invalid csb_addr. So an error message will
+	 * be displayed and leave it to user space whether to ignore or
+	 * handle this signal.
+	 */
+	rcu_read_lock();
+	rc = kill_pid_info(SIGSEGV, &info, pid);
+	rcu_read_unlock();
+
+	pr_devel("%s(): pid %d kill_proc_info() rc %d\n", __func__,
+			pid_vnr(pid), rc);
+}
+
+/*
  * Process valid CRBs in fault FIFO.
  * NX process user space requests, return credit and update the status
  * in CRB. If it encounters transalation error when accessing CRB or
@@ -124,8 +247,9 @@ irqreturn_t vas_fault_thread_fn(int irq, void *data)
 				vinst->fault_crbs);
 
 			WARN_ON_ONCE(1);
+		} else {
+			update_csb(window, crb);
 		}
-
 	}
 }
 
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v9 07/13] powerpc/vas: Setup thread IRQ handler per VAS instance
From: Haren Myneni @ 2020-04-01 21:28 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


When NX encounters translation error on CRB and any request buffer,
raises an interrupt on the CPU to handle the fault. It can raise one
interrupt for multiple faults. Expects OS to handle these faults and
return credits for fault window after processing faults.

Setup thread IRQ handler and IRQ thread function per each VAS instance.
IRQ handler checks if the thread is already woken up and can handle new
faults. If so returns with IRQ_HANDLED, otherwise wake up thread to
process new faults.

The thread functions reads each CRB entry from fault FIFO until sees
invalid entry. After reading each CRB, determine the corresponding
send window using pswid (from CRB) and process fault CRB. Then
invalidate the entry and return credit. Processing fault CRB and
return credit is described in subsequent patches.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-fault.c  | 131 ++++++++++++++++++++++++++++
 arch/powerpc/platforms/powernv/vas-window.c |  60 +++++++++++++
 arch/powerpc/platforms/powernv/vas.c        |  23 ++++-
 arch/powerpc/platforms/powernv/vas.h        |   7 ++
 4 files changed, 220 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/vas-fault.c b/arch/powerpc/platforms/powernv/vas-fault.c
index 4044998..0da8358 100644
--- a/arch/powerpc/platforms/powernv/vas-fault.c
+++ b/arch/powerpc/platforms/powernv/vas-fault.c
@@ -11,6 +11,7 @@
 #include <linux/slab.h>
 #include <linux/uaccess.h>
 #include <linux/kthread.h>
+#include <linux/mmu_context.h>
 #include <asm/icswx.h>
 
 #include "vas.h"
@@ -25,6 +26,136 @@
 #define VAS_FAULT_WIN_FIFO_SIZE	(4 << 20)
 
 /*
+ * Process valid CRBs in fault FIFO.
+ * NX process user space requests, return credit and update the status
+ * in CRB. If it encounters transalation error when accessing CRB or
+ * request buffers, raises interrupt on the CPU to handle the fault.
+ * It takes credit on fault window, updates nx_fault_stamp in CRB with
+ * the following information and pastes CRB in fault FIFO.
+ *
+ * pswid - window ID of the window on which the request is sent.
+ * fault_storage_addr - fault address
+ *
+ * It can raise a single interrupt for multiple faults. Expects OS to
+ * process all valid faults and return credit for each fault on user
+ * space and fault windows. This fault FIFO control will be done with
+ * credit mechanism. NX can continuously paste CRBs until credits are not
+ * available on fault window. Otherwise, returns with RMA_reject.
+ *
+ * Total credits available on fault window: FIFO_SIZE(4MB)/CRBS_SIZE(128)
+ *
+ */
+irqreturn_t vas_fault_thread_fn(int irq, void *data)
+{
+	struct vas_instance *vinst = data;
+	struct coprocessor_request_block *crb, *entry;
+	struct coprocessor_request_block buf;
+	struct vas_window *window;
+	unsigned long flags;
+	void *fifo;
+
+	crb = &buf;
+
+	/*
+	 * VAS can interrupt with multiple page faults. So process all
+	 * valid CRBs within fault FIFO until reaches invalid CRB.
+	 * We use CCW[0] and pswid to validate validate CRBs:
+	 *
+	 * CCW[0]	Reserved bit. When NX pastes CRB, CCW[0]=0
+	 *		OS sets this bit to 1 after reading CRB.
+	 * pswid	NX assigns window ID. Set pswid to -1 after
+	 *		reading CRB from fault FIFO.
+	 *
+	 * We exit this function if no valid CRBs are available to process.
+	 * So acquire fault_lock and reset fifo_in_progress to 0 before
+	 * exit.
+	 * In case kernel receives another interrupt with different page
+	 * fault, interrupt handler returns with IRQ_HANDLED if
+	 * fifo_in_progress is set. Means these new faults will be
+	 * handled by the current thread. Otherwise set fifo_in_progress
+	 * and return IRQ_WAKE_THREAD to wake up thread.
+	 */
+	while (true) {
+		spin_lock_irqsave(&vinst->fault_lock, flags);
+		/*
+		 * Advance the fault fifo pointer to next CRB.
+		 * Use CRB_SIZE rather than sizeof(*crb) since the latter is
+		 * aligned to CRB_ALIGN (256) but the CRB written to by VAS is
+		 * only CRB_SIZE in len.
+		 */
+		fifo = vinst->fault_fifo + (vinst->fault_crbs * CRB_SIZE);
+		entry = fifo;
+
+		if ((entry->stamp.nx.pswid == cpu_to_be32(FIFO_INVALID_ENTRY))
+			|| (entry->ccw & cpu_to_be32(CCW0_INVALID))) {
+			vinst->fifo_in_progress = 0;
+			spin_unlock_irqrestore(&vinst->fault_lock, flags);
+			return IRQ_HANDLED;
+		}
+
+		spin_unlock_irqrestore(&vinst->fault_lock, flags);
+		vinst->fault_crbs++;
+		if (vinst->fault_crbs == (vinst->fault_fifo_size / CRB_SIZE))
+			vinst->fault_crbs = 0;
+
+		memcpy(crb, fifo, CRB_SIZE);
+		entry->stamp.nx.pswid = cpu_to_be32(FIFO_INVALID_ENTRY);
+		entry->ccw |= cpu_to_be32(CCW0_INVALID);
+
+		pr_devel("VAS[%d] fault_fifo %p, fifo %p, fault_crbs %d\n",
+				vinst->vas_id, vinst->fault_fifo, fifo,
+				vinst->fault_crbs);
+
+		window = vas_pswid_to_window(vinst,
+				be32_to_cpu(crb->stamp.nx.pswid));
+
+		if (IS_ERR(window)) {
+			/*
+			 * We got an interrupt about a specific send
+			 * window but we can't find that window and we can't
+			 * even clean it up (return credit on user space
+			 * window).
+			 * But we should not get here.
+			 * TODO: Disable IRQ.
+			 */
+			pr_err("VAS[%d] fault_fifo %p, fifo %p, pswid 0x%x, fault_crbs %d bad CRB?\n",
+				vinst->vas_id, vinst->fault_fifo, fifo,
+				be32_to_cpu(crb->stamp.nx.pswid),
+				vinst->fault_crbs);
+
+			WARN_ON_ONCE(1);
+		}
+
+	}
+}
+
+irqreturn_t vas_fault_handler(int irq, void *dev_id)
+{
+	struct vas_instance *vinst = dev_id;
+	irqreturn_t ret = IRQ_WAKE_THREAD;
+	unsigned long flags;
+
+	/*
+	 * NX can generate an interrupt for multiple faults. So the
+	 * fault handler thread process all CRBs until finds invalid
+	 * entry. In case if NX sees continuous faults, it is possible
+	 * that the thread function entered with the first interrupt
+	 * can execute and process all valid CRBs.
+	 * So wake up thread only if the fault thread is not in progress.
+	 */
+	spin_lock_irqsave(&vinst->fault_lock, flags);
+
+	if (vinst->fifo_in_progress)
+		ret = IRQ_HANDLED;
+	else
+		vinst->fifo_in_progress = 1;
+
+	spin_unlock_irqrestore(&vinst->fault_lock, flags);
+
+	return ret;
+}
+
+/*
  * Fault window is opened per VAS instance. NX pastes fault CRB in fault
  * FIFO upon page faults.
  */
diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index 7054cd4..382fe25 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1050,6 +1050,15 @@ struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
 		}
 	} else {
 		/*
+		 * Interrupt hanlder or fault window setup failed. Means
+		 * NX can not generate fault for page fault. So not
+		 * opening for user space tx window.
+		 */
+		if (!vinst->virq) {
+			rc = -ENODEV;
+			goto free_window;
+		}
+		/*
 		 * A user mapping must ensure that context switch issues
 		 * CP_ABORT for this thread.
 		 */
@@ -1308,3 +1317,54 @@ int vas_win_close(struct vas_window *window)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(vas_win_close);
+
+struct vas_window *vas_pswid_to_window(struct vas_instance *vinst,
+		uint32_t pswid)
+{
+	struct vas_window *window;
+	int winid;
+
+	if (!pswid) {
+		pr_devel("%s: called for pswid 0!\n", __func__);
+		return ERR_PTR(-ESRCH);
+	}
+
+	decode_pswid(pswid, NULL, &winid);
+
+	if (winid >= VAS_WINDOWS_PER_CHIP)
+		return ERR_PTR(-ESRCH);
+
+	/*
+	 * If application closes the window before the hardware
+	 * returns the fault CRB, we should wait in vas_win_close()
+	 * for the pending requests. so the window must be active
+	 * and the process alive.
+	 *
+	 * If its a kernel process, we should not get any faults and
+	 * should not get here.
+	 */
+	window = vinst->windows[winid];
+
+	if (!window) {
+		pr_err("PSWID decode: Could not find window for winid %d pswid %d vinst 0x%p\n",
+			winid, pswid, vinst);
+		return NULL;
+	}
+
+	/*
+	 * Do some sanity checks on the decoded window.  Window should be
+	 * NX GZIP user send window. FTW windows should not incur faults
+	 * since their CRBs are ignored (not queued on FIFO or processed
+	 * by NX).
+	 */
+	if (!window->tx_win || !window->user_win || !window->nx_win ||
+			window->cop == VAS_COP_TYPE_FAULT ||
+			window->cop == VAS_COP_TYPE_FTW) {
+		pr_err("PSWID decode: id %d, tx %d, user %d, nx %d, cop %d\n",
+			winid, window->tx_win, window->user_win,
+			window->nx_win, window->cop);
+		WARN_ON(1);
+	}
+
+	return window;
+}
diff --git a/arch/powerpc/platforms/powernv/vas.c b/arch/powerpc/platforms/powernv/vas.c
index 9013a63..598e4cd 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -14,6 +14,8 @@
 #include <linux/of_platform.h>
 #include <linux/of_address.h>
 #include <linux/of.h>
+#include <linux/irqdomain.h>
+#include <linux/interrupt.h>
 #include <asm/prom.h>
 #include <asm/xive.h>
 
@@ -26,7 +28,25 @@
 
 static int vas_irq_fault_window_setup(struct vas_instance *vinst)
 {
-	return vas_setup_fault_window(vinst);
+	char devname[64];
+	int rc = 0;
+
+	snprintf(devname, sizeof(devname), "vas-%d", vinst->vas_id);
+	rc = request_threaded_irq(vinst->virq, vas_fault_handler,
+				vas_fault_thread_fn, 0, devname, vinst);
+
+	if (rc) {
+		pr_err("VAS[%d]: Request IRQ(%d) failed with %d\n",
+				vinst->vas_id, vinst->virq, rc);
+		goto out;
+	}
+
+	rc = vas_setup_fault_window(vinst);
+	if (rc)
+		free_irq(vinst->virq, vinst);
+
+out:
+	return rc;
 }
 
 static int init_vas_instance(struct platform_device *pdev)
@@ -119,6 +139,7 @@ static int init_vas_instance(struct platform_device *pdev)
 	list_add(&vinst->node, &vas_instances);
 	mutex_unlock(&vas_mutex);
 
+	spin_lock_init(&vinst->fault_lock);
 	/*
 	 * IRQ and fault handling setup is needed only for user space
 	 * send windows.
diff --git a/arch/powerpc/platforms/powernv/vas.h b/arch/powerpc/platforms/powernv/vas.h
index 2a04072..0af7912 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -331,7 +331,10 @@ struct vas_instance {
 
 	u64 irq_port;
 	int virq;
+	int fault_crbs;
 	int fault_fifo_size;
+	int fifo_in_progress;
+	spinlock_t fault_lock;
 	void *fault_fifo;
 	struct vas_window *fault_win; /* Fault window */
 
@@ -431,6 +434,10 @@ struct vas_winctx {
 extern void vas_window_init_dbgdir(struct vas_window *win);
 extern void vas_window_free_dbgdir(struct vas_window *win);
 extern int vas_setup_fault_window(struct vas_instance *vinst);
+extern irqreturn_t vas_fault_thread_fn(int irq, void *data);
+extern irqreturn_t vas_fault_handler(int irq, void *dev_id);
+extern struct vas_window *vas_pswid_to_window(struct vas_instance *vinst,
+						uint32_t pswid);
 
 static inline int vas_window_pid(struct vas_window *window)
 {
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH 06/13] powerpc/vas: Take reference to PID and mm for user space windows
From: Haren Myneni @ 2020-04-01 21:28 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


When process opens a window, its pid and tgid will be saved in the
vas_window struct. This window will be closed when the process exits.
The kernel handles NX faults by updating CSB or send SEGV signal to pid
of the process if the userspace csb addr is invalid.

In multi-thread applications, a window can be opened by a child thread,
but it will not be closed when this thread exits. It is expected that
the parent will clean up all resources including NX windows opened by
child threads. A child thread can send NX requests using this window
and could be killed before completion is reported. If the pid assigned
to this thread is reused while requests are pending, a failure SEGV
would be directed to the wrong place.

To prevent reusing the pid, take references to pid and mm when the window
is opened and release them when when the window is closed. Then if child
thread is not running, SEGV signal will be sent to thread group leader
(tgd).

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-debug.c  |  2 +-
 arch/powerpc/platforms/powernv/vas-window.c | 53 ++++++++++++++++++++++++++---
 arch/powerpc/platforms/powernv/vas.h        |  9 ++++-
 3 files changed, 57 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-debug.c b/arch/powerpc/platforms/powernv/vas-debug.c
index 09e63df..ef9a717 100644
--- a/arch/powerpc/platforms/powernv/vas-debug.c
+++ b/arch/powerpc/platforms/powernv/vas-debug.c
@@ -38,7 +38,7 @@ static int info_show(struct seq_file *s, void *private)
 
 	seq_printf(s, "Type: %s, %s\n", cop_to_str(window->cop),
 					window->tx_win ? "Send" : "Receive");
-	seq_printf(s, "Pid : %d\n", window->pid);
+	seq_printf(s, "Pid : %d\n", vas_window_pid(window));
 
 unlock:
 	mutex_unlock(&vas_mutex);
diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index dc46bf6..7054cd4 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -12,6 +12,8 @@
 #include <linux/log2.h>
 #include <linux/rcupdate.h>
 #include <linux/cred.h>
+#include <linux/sched/mm.h>
+#include <linux/mmu_context.h>
 #include <asm/switch_to.h>
 #include <asm/ppc-opcode.h>
 #include "vas.h"
@@ -876,8 +878,6 @@ struct vas_window *vas_rx_win_open(int vasid, enum vas_cop_type cop,
 	rxwin->user_win = rxattr->user_win;
 	rxwin->cop = cop;
 	rxwin->wcreds_max = rxattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
-	if (rxattr->user_win)
-		rxwin->pid = task_pid_vnr(current);
 
 	init_winctx_for_rxwin(rxwin, rxattr, &winctx);
 	init_winctx_regs(rxwin, &winctx);
@@ -1027,7 +1027,6 @@ struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
 	txwin->tx_win = 1;
 	txwin->rxwin = rxwin;
 	txwin->nx_win = txwin->rxwin->nx_win;
-	txwin->pid = attr->pid;
 	txwin->user_win = attr->user_win;
 	txwin->wcreds_max = attr->wcreds_max ?: VAS_WCREDS_DEFAULT;
 
@@ -1059,8 +1058,43 @@ struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
 			goto free_window;
 	}
 
-	set_vinst_win(vinst, txwin);
+	if (txwin->user_win) {
+		/*
+		 * Window opened by a child thread may not be closed when
+		 * it exits. So take reference to its pid and release it
+		 * when the window is free by parent thread.
+		 * Acquire a reference to the task's pid to make sure
+		 * pid will not be re-used - needed only for multithread
+		 * applications.
+		 */
+		txwin->pid = get_task_pid(current, PIDTYPE_PID);
+		/*
+		 * Acquire a reference to the task's mm.
+		 */
+		txwin->mm = get_task_mm(current);
 
+		if (!txwin->mm) {
+			put_pid(txwin->pid);
+			pr_err("VAS: pid(%d): mm_struct is not found\n",
+					current->pid);
+			rc = -EPERM;
+			goto free_window;
+		}
+
+		mmgrab(txwin->mm);
+		mmput(txwin->mm);
+		mm_context_add_copro(txwin->mm);
+		/*
+		 * Process closes window during exit. In the case of
+		 * multithread application, the child thread can open
+		 * window and can exit without closing it. Expects parent
+		 * thread to use and close the window. So do not need
+		 * to take pid reference for parent thread.
+		 */
+		txwin->tgid = find_get_pid(task_tgid_vnr(current));
+	}
+
+	set_vinst_win(vinst, txwin);
 	return txwin;
 
 free_window:
@@ -1257,8 +1291,17 @@ int vas_win_close(struct vas_window *window)
 	poll_window_castout(window);
 
 	/* if send window, drop reference to matching receive window */
-	if (window->tx_win)
+	if (window->tx_win) {
+		if (window->user_win) {
+			/* Drop references to pid and mm */
+			put_pid(window->pid);
+			if (window->mm) {
+				mm_context_remove_copro(window->mm);
+				mmdrop(window->mm);
+			}
+		}
 		put_rx_win(window->rxwin);
+	}
 
 	vas_window_free(window);
 
diff --git a/arch/powerpc/platforms/powernv/vas.h b/arch/powerpc/platforms/powernv/vas.h
index 88d084d..2a04072 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -355,7 +355,9 @@ struct vas_window {
 	bool user_win;		/* True if user space window */
 	void *hvwc_map;		/* HV window context */
 	void *uwc_map;		/* OS/User window context */
-	pid_t pid;		/* Linux process id of owner */
+	struct pid *pid;	/* Linux process id of owner */
+	struct pid *tgid;	/* Thread group ID of owner */
+	struct mm_struct *mm;	/* Linux process mm_struct */
 	int wcreds_max;		/* Window credits */
 
 	char *dbgname;
@@ -430,6 +432,11 @@ struct vas_winctx {
 extern void vas_window_free_dbgdir(struct vas_window *win);
 extern int vas_setup_fault_window(struct vas_instance *vinst);
 
+static inline int vas_window_pid(struct vas_window *window)
+{
+	return pid_vnr(window->pid);
+}
+
 static inline void vas_log_write(struct vas_window *win, char *name,
 			void *regptr, u64 val)
 {
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v9 05/13] powerpc/vas: Register NX with fault window ID and IRQ port value
From: Haren Myneni @ 2020-04-01 21:27 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


For each user space send window, register NX with fault window ID
and port value so that NX paste CRBs in this fault FIFO when it
sees fault on the request buffer.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 15 +++++++++++++--
 arch/powerpc/platforms/powernv/vas.h        | 15 +++++++++++++++
 2 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index 1783fa9..dc46bf6 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -373,7 +373,7 @@ int init_winctx_regs(struct vas_window *window, struct vas_winctx *winctx)
 	init_xlate_regs(window, winctx->user_win);
 
 	val = 0ULL;
-	val = SET_FIELD(VAS_FAULT_TX_WIN, val, 0);
+	val = SET_FIELD(VAS_FAULT_TX_WIN, val, winctx->fault_win_id);
 	write_hvwc_reg(window, VREG(FAULT_TX_WIN), val);
 
 	/* In PowerNV, interrupts go to HV. */
@@ -748,6 +748,8 @@ static void init_winctx_for_rxwin(struct vas_window *rxwin,
 
 	winctx->min_scope = VAS_SCOPE_LOCAL;
 	winctx->max_scope = VAS_SCOPE_VECTORED_GROUP;
+	if (rxwin->vinst->virq)
+		winctx->irq_port = rxwin->vinst->irq_port;
 }
 
 static bool rx_win_args_valid(enum vas_cop_type cop,
@@ -944,13 +946,22 @@ static void init_winctx_for_txwin(struct vas_window *txwin,
 	winctx->lpid = txattr->lpid;
 	winctx->pidr = txattr->pidr;
 	winctx->rx_win_id = txwin->rxwin->winid;
+	/*
+	 * IRQ and fault window setup is successful. Set fault window
+	 * for the send window so that ready to handle faults.
+	 */
+	if (txwin->vinst->virq)
+		winctx->fault_win_id = txwin->vinst->fault_win->winid;
 
 	winctx->dma_type = VAS_DMA_TYPE_INJECT;
 	winctx->tc_mode = txattr->tc_mode;
 	winctx->min_scope = VAS_SCOPE_LOCAL;
 	winctx->max_scope = VAS_SCOPE_VECTORED_GROUP;
+	if (txwin->vinst->virq)
+		winctx->irq_port = txwin->vinst->irq_port;
 
-	winctx->pswid = 0;
+	winctx->pswid = txattr->pswid ? txattr->pswid :
+			encode_pswid(txwin->vinst->vas_id, txwin->winid);
 }
 
 static bool tx_win_args_valid(enum vas_cop_type cop,
diff --git a/arch/powerpc/platforms/powernv/vas.h b/arch/powerpc/platforms/powernv/vas.h
index 9c8e3f5..88d084d 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -467,6 +467,21 @@ static inline u64 read_hvwc_reg(struct vas_window *win,
 	return in_be64(win->hvwc_map+reg);
 }
 
+/*
+ * Encode/decode the Partition Send Window ID (PSWID) for a window in
+ * a way that we can uniquely identify any window in the system. i.e.
+ * we should be able to locate the 'struct vas_window' given the PSWID.
+ *
+ *	Bits	Usage
+ *	0:7	VAS id (8 bits)
+ *	8:15	Unused, 0 (3 bits)
+ *	16:31	Window id (16 bits)
+ */
+static inline u32 encode_pswid(int vasid, int winid)
+{
+	return ((u32)winid | (vasid << (31 - 7)));
+}
+
 static inline void decode_pswid(u32 pswid, int *vasid, int *winid)
 {
 	if (vasid)
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v9 04/13] powerpc/vas: Setup fault window per VAS instance
From: Haren Myneni @ 2020-04-01 21:26 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


Setup fault window for each VAS instance. When NX gets a fault on
request buffer, pastes fault CRB in the corresponding fault FIFO and
then raises an interrupt to the OS. The kernel handles this fault
and process faults CRB from this FIFO.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/Makefile     |  2 +-
 arch/powerpc/platforms/powernv/vas-fault.c  | 77 +++++++++++++++++++++++++++++
 arch/powerpc/platforms/powernv/vas-window.c |  4 +-
 arch/powerpc/platforms/powernv/vas.c        | 20 ++++++++
 arch/powerpc/platforms/powernv/vas.h        | 21 ++++++++
 5 files changed, 121 insertions(+), 3 deletions(-)
 create mode 100644 arch/powerpc/platforms/powernv/vas-fault.c

diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile
index c0f8120..395789f 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -17,7 +17,7 @@ obj-$(CONFIG_MEMORY_FAILURE)	+= opal-memory-errors.o
 obj-$(CONFIG_OPAL_PRD)	+= opal-prd.o
 obj-$(CONFIG_PERF_EVENTS) += opal-imc.o
 obj-$(CONFIG_PPC_MEMTRACE)	+= memtrace.o
-obj-$(CONFIG_PPC_VAS)	+= vas.o vas-window.o vas-debug.o
+obj-$(CONFIG_PPC_VAS)	+= vas.o vas-window.o vas-debug.o vas-fault.o
 obj-$(CONFIG_OCXL_BASE)	+= ocxl.o
 obj-$(CONFIG_SCOM_DEBUGFS) += opal-xscom.o
 obj-$(CONFIG_PPC_SECURE_BOOT) += opal-secvar.o
diff --git a/arch/powerpc/platforms/powernv/vas-fault.c b/arch/powerpc/platforms/powernv/vas-fault.c
new file mode 100644
index 0000000..4044998
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-fault.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * VAS Fault handling.
+ * Copyright 2019, IBM Corporation
+ */
+
+#define pr_fmt(fmt) "vas: " fmt
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/kthread.h>
+#include <asm/icswx.h>
+
+#include "vas.h"
+
+/*
+ * The maximum FIFO size for fault window can be 8MB
+ * (VAS_RX_FIFO_SIZE_MAX). Using 4MB FIFO since each VAS
+ * instance will be having fault window.
+ * 8MB FIFO can be used if expects more faults for each VAS
+ * instance.
+ */
+#define VAS_FAULT_WIN_FIFO_SIZE	(4 << 20)
+
+/*
+ * Fault window is opened per VAS instance. NX pastes fault CRB in fault
+ * FIFO upon page faults.
+ */
+int vas_setup_fault_window(struct vas_instance *vinst)
+{
+	struct vas_rx_win_attr attr;
+
+	vinst->fault_fifo_size = VAS_FAULT_WIN_FIFO_SIZE;
+	vinst->fault_fifo = kzalloc(vinst->fault_fifo_size, GFP_KERNEL);
+	if (!vinst->fault_fifo) {
+		pr_err("Unable to alloc %d bytes for fault_fifo\n",
+				vinst->fault_fifo_size);
+		return -ENOMEM;
+	}
+
+	/*
+	 * Invalidate all CRB entries. NX pastes valid entry for each fault.
+	 */
+	memset(vinst->fault_fifo, FIFO_INVALID_ENTRY, vinst->fault_fifo_size);
+	vas_init_rx_win_attr(&attr, VAS_COP_TYPE_FAULT);
+
+	attr.rx_fifo_size = vinst->fault_fifo_size;
+	attr.rx_fifo = vinst->fault_fifo;
+
+	/*
+	 * Max creds is based on number of CRBs can fit in the FIFO.
+	 * (fault_fifo_size/CRB_SIZE). If 8MB FIFO is used, max creds
+	 * will be 0xffff since the receive creds field is 16bits wide.
+	 */
+	attr.wcreds_max = vinst->fault_fifo_size / CRB_SIZE;
+	attr.lnotify_lpid = 0;
+	attr.lnotify_pid = mfspr(SPRN_PID);
+	attr.lnotify_tid = mfspr(SPRN_PID);
+
+	vinst->fault_win = vas_rx_win_open(vinst->vas_id, VAS_COP_TYPE_FAULT,
+					&attr);
+
+	if (IS_ERR(vinst->fault_win)) {
+		pr_err("VAS: Error %ld opening FaultWin\n",
+			PTR_ERR(vinst->fault_win));
+		kfree(vinst->fault_fifo);
+		return PTR_ERR(vinst->fault_win);
+	}
+
+	pr_devel("VAS: Created FaultWin %d, LPID/PID/TID [%d/%d/%d]\n",
+			vinst->fault_win->winid, attr.lnotify_lpid,
+			attr.lnotify_pid, attr.lnotify_tid);
+
+	return 0;
+}
diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index 0c0d27d..1783fa9 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -827,9 +827,9 @@ void vas_init_rx_win_attr(struct vas_rx_win_attr *rxattr, enum vas_cop_type cop)
 		rxattr->fault_win = true;
 		rxattr->notify_disable = true;
 		rxattr->rx_wcred_mode = true;
-		rxattr->tx_wcred_mode = true;
 		rxattr->rx_win_ord_mode = true;
-		rxattr->tx_win_ord_mode = true;
+		rxattr->rej_no_credit = true;
+		rxattr->tc_mode = VAS_THRESH_DISABLED;
 	} else if (cop == VAS_COP_TYPE_FTW) {
 		rxattr->user_win = true;
 		rxattr->intr_disable = true;
diff --git a/arch/powerpc/platforms/powernv/vas.c b/arch/powerpc/platforms/powernv/vas.c
index 3303cfe..9013a63 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -24,6 +24,11 @@
 
 static DEFINE_PER_CPU(int, cpu_vas_id);
 
+static int vas_irq_fault_window_setup(struct vas_instance *vinst)
+{
+	return vas_setup_fault_window(vinst);
+}
+
 static int init_vas_instance(struct platform_device *pdev)
 {
 	struct device_node *dn = pdev->dev.of_node;
@@ -114,6 +119,21 @@ static int init_vas_instance(struct platform_device *pdev)
 	list_add(&vinst->node, &vas_instances);
 	mutex_unlock(&vas_mutex);
 
+	/*
+	 * IRQ and fault handling setup is needed only for user space
+	 * send windows.
+	 */
+	if (vinst->virq) {
+		rc = vas_irq_fault_window_setup(vinst);
+		/*
+		 * Fault window is used only for user space send windows.
+		 * So if vinst->virq is NULL, tx_win_open returns -ENODEV
+		 * for user space.
+		 */
+		if (rc)
+			vinst->virq = 0;
+	}
+
 	vas_instance_init_dbgdir(vinst);
 
 	dev_set_drvdata(&pdev->dev, vinst);
diff --git a/arch/powerpc/platforms/powernv/vas.h b/arch/powerpc/platforms/powernv/vas.h
index 598608b..9c8e3f5 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -296,6 +296,22 @@ enum vas_notify_after_count {
 };
 
 /*
+ * NX can generate an interrupt for multiple faults and expects kernel
+ * to process all of them. So read all valid CRB entries until find the
+ * invalid one. So use pswid which is pasted by NX and ccw[0] (reserved
+ * bit in BE) to check valid CRB. CCW[0] will not be touched by user
+ * space. Application gets CRB formt error if it updates this bit.
+ *
+ * Invalidate FIFO during allocation and process all entries from last
+ * successful read until finds invalid pswid and ccw[0] values.
+ * After reading each CRB entry from fault FIFO, the kernel invalidate
+ * it by updating pswid with FIFO_INVALID_ENTRY and CCW[0] with
+ * CCW0_INVALID.
+ */
+#define FIFO_INVALID_ENTRY	0xffffffff
+#define CCW0_INVALID		1
+
+/*
  * One per instance of VAS. Each instance will have a separate set of
  * receive windows, one per coprocessor type.
  *
@@ -315,6 +331,10 @@ struct vas_instance {
 
 	u64 irq_port;
 	int virq;
+	int fault_fifo_size;
+	void *fault_fifo;
+	struct vas_window *fault_win; /* Fault window */
+
 	struct mutex mutex;
 	struct vas_window *rxwin[VAS_COP_TYPE_MAX];
 	struct vas_window *windows[VAS_WINDOWS_PER_CHIP];
@@ -408,6 +428,7 @@ struct vas_winctx {
 extern void vas_instance_init_dbgdir(struct vas_instance *vinst);
 extern void vas_window_init_dbgdir(struct vas_window *win);
 extern void vas_window_free_dbgdir(struct vas_window *win);
+extern int vas_setup_fault_window(struct vas_instance *vinst);
 
 static inline void vas_log_write(struct vas_window *win, char *name,
 			void *regptr, u64 val)
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v9 03/13] powerpc/vas: Alloc and setup IRQ and trigger port address
From: Haren Myneni @ 2020-04-01 21:26 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


Allocate a xive irq on each chip with a vas instance. The NX coprocessor
raises a host CPU interrupt via vas if it encounters page fault on user
space request buffer. Subsequent patches register the trigger port with
the NX coprocessor, and create a vas fault handler for this interrupt
mapping.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/platforms/powernv/vas.c | 44 +++++++++++++++++++++++++++++++-----
 arch/powerpc/platforms/powernv/vas.h |  2 ++
 2 files changed, 40 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas.c b/arch/powerpc/platforms/powernv/vas.c
index ed9cc6d..3303cfe 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -15,6 +15,7 @@
 #include <linux/of_address.h>
 #include <linux/of.h>
 #include <asm/prom.h>
+#include <asm/xive.h>
 
 #include "vas.h"
 
@@ -25,10 +26,12 @@
 
 static int init_vas_instance(struct platform_device *pdev)
 {
-	int rc, cpu, vasid;
-	struct resource *res;
-	struct vas_instance *vinst;
 	struct device_node *dn = pdev->dev.of_node;
+	struct vas_instance *vinst;
+	struct xive_irq_data *xd;
+	uint32_t chipid, hwirq;
+	struct resource *res;
+	int rc, cpu, vasid;
 
 	rc = of_property_read_u32(dn, "ibm,vas-id", &vasid);
 	if (rc) {
@@ -36,6 +39,12 @@ static int init_vas_instance(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
+	rc = of_property_read_u32(dn, "ibm,chip-id", &chipid);
+	if (rc) {
+		pr_err("No ibm,chip-id property for %s?\n", pdev->name);
+		return -ENODEV;
+	}
+
 	if (pdev->num_resources != 4) {
 		pr_err("Unexpected DT configuration for [%s, %d]\n",
 				pdev->name, vasid);
@@ -69,9 +78,32 @@ static int init_vas_instance(struct platform_device *pdev)
 
 	vinst->paste_win_id_shift = 63 - res->end;
 
-	pr_devel("Initialized instance [%s, %d], paste_base 0x%llx, "
-			"paste_win_id_shift 0x%llx\n", pdev->name, vasid,
-			vinst->paste_base_addr, vinst->paste_win_id_shift);
+	hwirq = xive_native_alloc_irq_on_chip(chipid);
+	if (!hwirq) {
+		pr_err("Inst%d: Unable to allocate global irq for chip %d\n",
+				vinst->vas_id, chipid);
+		return -ENOENT;
+	}
+
+	vinst->virq = irq_create_mapping(NULL, hwirq);
+	if (!vinst->virq) {
+		pr_err("Inst%d: Unable to map global irq %d\n",
+				vinst->vas_id, hwirq);
+		return -EINVAL;
+	}
+
+	xd = irq_get_handler_data(vinst->virq);
+	if (!xd) {
+		pr_err("Inst%d: Invalid virq %d\n",
+				vinst->vas_id, vinst->virq);
+		return -EINVAL;
+	}
+
+	vinst->irq_port = xd->trig_page;
+	pr_devel("Initialized instance [%s, %d] paste_base 0x%llx paste_win_id_shift 0x%llx IRQ %d Port 0x%llx\n",
+			pdev->name, vasid, vinst->paste_base_addr,
+			vinst->paste_win_id_shift, vinst->virq,
+			vinst->irq_port);
 
 	for_each_possible_cpu(cpu) {
 		if (cpu_to_chip_id(cpu) == of_get_ibm_chip_id(dn))
diff --git a/arch/powerpc/platforms/powernv/vas.h b/arch/powerpc/platforms/powernv/vas.h
index 5574aec..598608b 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -313,6 +313,8 @@ struct vas_instance {
 	u64 paste_base_addr;
 	u64 paste_win_id_shift;
 
+	u64 irq_port;
+	int virq;
 	struct mutex mutex;
 	struct vas_window *rxwin[VAS_COP_TYPE_MAX];
 	struct vas_window *windows[VAS_WINDOWS_PER_CHIP];
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v9 02/13] powerpc/vas: Define nx_fault_stamp in coprocessor_request_block
From: Haren Myneni @ 2020-04-01 21:25 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


Kernel sets fault address and status in CRB for NX page fault on user
space address after processing page fault. User space gets the signal
and handles the fault mentioned in CRB by bringing the page in to
memory and send NX request again.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
 arch/powerpc/include/asm/icswx.h | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/icswx.h b/arch/powerpc/include/asm/icswx.h
index 9872f85..965b1f3 100644
--- a/arch/powerpc/include/asm/icswx.h
+++ b/arch/powerpc/include/asm/icswx.h
@@ -108,6 +108,17 @@ struct data_descriptor_entry {
 	__be64 address;
 } __packed __aligned(DDE_ALIGN);
 
+/* 4.3.2 NX-stamped Fault CRB */
+
+#define NX_STAMP_ALIGN          (0x10)
+
+struct nx_fault_stamp {
+	__be64 fault_storage_addr;
+	__be16 reserved;
+	__u8   flags;
+	__u8   fault_status;
+	__be32 pswid;
+} __packed __aligned(NX_STAMP_ALIGN);
 
 /* Chapter 6.5.2 Coprocessor-Request Block (CRB) */
 
@@ -135,10 +146,15 @@ struct coprocessor_request_block {
 
 	struct coprocessor_completion_block ccb;
 
-	u8 reserved[48];
+	union {
+		struct nx_fault_stamp nx;
+		u8 reserved[16];
+	} stamp;
+
+	u8 reserved[32];
 
 	struct coprocessor_status_block csb;
-} __packed __aligned(CRB_ALIGN);
+} __packed;
 
 
 /* RFC02167 Initiate Coprocessor Instructions document
-- 
1.8.3.1




^ permalink raw reply related

* [PATCH v9 01/13] powerpc/xive: Define xive_native_alloc_irq_on_chip()
From: Haren Myneni @ 2020-04-01 21:25 UTC (permalink / raw)
  To: mpe
  Cc: mikey, srikar, frederic.barrat, ajd, linux-kernel, npiggin, hch,
	oohall, clg, sukadev, linuxppc-dev, herbert
In-Reply-To: <1585775978.10664.438.camel@hbabu-laptop>


This function allocates IRQ on a specific chip. VAS needs per chip
IRQ allocation and will have IRQ handler per VAS instance.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
---
 arch/powerpc/include/asm/xive.h   | 9 ++++++++-
 arch/powerpc/sysdev/xive/native.c | 6 +++---
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/include/asm/xive.h b/arch/powerpc/include/asm/xive.h
index 93f982db..d08ea11 100644
--- a/arch/powerpc/include/asm/xive.h
+++ b/arch/powerpc/include/asm/xive.h
@@ -5,6 +5,8 @@
 #ifndef _ASM_POWERPC_XIVE_H
 #define _ASM_POWERPC_XIVE_H
 
+#include <asm/opal-api.h>
+
 #define XIVE_INVALID_VP	0xffffffff
 
 #ifdef CONFIG_PPC_XIVE
@@ -108,7 +110,6 @@ struct xive_q {
 int xive_native_populate_irq_data(u32 hw_irq,
 				  struct xive_irq_data *data);
 void xive_cleanup_irq_data(struct xive_irq_data *xd);
-u32 xive_native_alloc_irq(void);
 void xive_native_free_irq(u32 irq);
 int xive_native_configure_irq(u32 hw_irq, u32 target, u8 prio, u32 sw_irq);
 
@@ -137,6 +138,12 @@ int xive_native_set_queue_state(u32 vp_id, uint32_t prio, u32 qtoggle,
 				u32 qindex);
 int xive_native_get_vp_state(u32 vp_id, u64 *out_state);
 bool xive_native_has_queue_state_support(void);
+extern u32 xive_native_alloc_irq_on_chip(u32 chip_id);
+
+static inline u32 xive_native_alloc_irq(void)
+{
+	return xive_native_alloc_irq_on_chip(OPAL_XIVE_ANY_CHIP);
+}
 
 #else
 
diff --git a/arch/powerpc/sysdev/xive/native.c b/arch/powerpc/sysdev/xive/native.c
index 0ff6b73..14d4406 100644
--- a/arch/powerpc/sysdev/xive/native.c
+++ b/arch/powerpc/sysdev/xive/native.c
@@ -279,12 +279,12 @@ static int xive_native_get_ipi(unsigned int cpu, struct xive_cpu *xc)
 }
 #endif /* CONFIG_SMP */
 
-u32 xive_native_alloc_irq(void)
+u32 xive_native_alloc_irq_on_chip(u32 chip_id)
 {
 	s64 rc;
 
 	for (;;) {
-		rc = opal_xive_allocate_irq(OPAL_XIVE_ANY_CHIP);
+		rc = opal_xive_allocate_irq(chip_id);
 		if (rc != OPAL_BUSY)
 			break;
 		msleep(OPAL_BUSY_DELAY_MS);
@@ -293,7 +293,7 @@ u32 xive_native_alloc_irq(void)
 		return 0;
 	return rc;
 }
-EXPORT_SYMBOL_GPL(xive_native_alloc_irq);
+EXPORT_SYMBOL_GPL(xive_native_alloc_irq_on_chip);
 
 void xive_native_free_irq(u32 irq)
 {
-- 
1.8.3.1




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