1 files changed, 294 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
new file mode 100644
index 000000000..c36f71e01
--- /dev/null
+++ b/arch/powerpc/include/asm/vas.h
@@ -0,0 +1,294 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright 2016-17 IBM Corp.
+ */
+
+#ifndef _ASM_POWERPC_VAS_H
+#define _ASM_POWERPC_VAS_H
+#include <linux/sched/mm.h>
+#include <linux/mmu_context.h>
+#include <asm/icswx.h>
+#include <uapi/asm/vas-api.h>
+
+/*
+ * Min and max FIFO sizes are based on Version 1.05 Section 3.1.4.25
+ * (Local FIFO Size Register) of the VAS workbook.
+ */
+#define VAS_RX_FIFO_SIZE_MIN	(1 << 10)	/* 1KB */
+#define VAS_RX_FIFO_SIZE_MAX	(8 << 20)	/* 8MB */
+
+/*
+ * Threshold Control Mode: Have paste operation fail if the number of
+ * requests in receive FIFO exceeds a threshold.
+ *
+ * NOTE: No special error code yet if paste is rejected because of these
+ *	 limits. So users can't distinguish between this and other errors.
+ */
+#define VAS_THRESH_DISABLED		0
+#define VAS_THRESH_FIFO_GT_HALF_FULL	1
+#define VAS_THRESH_FIFO_GT_QTR_FULL	2
+#define VAS_THRESH_FIFO_GT_EIGHTH_FULL	3
+
+/*
+ * VAS window Linux status bits
+ */
+#define VAS_WIN_ACTIVE		0x0	/* Used in platform independent */
+					/* vas mmap() */
+/* Window is closed in the hypervisor due to lost credit */
+#define VAS_WIN_NO_CRED_CLOSE	0x00000001
+/* Window is closed due to migration */
+#define VAS_WIN_MIGRATE_CLOSE	0x00000002
+
+/*
+ * Get/Set bit fields
+ */
+#define GET_FIELD(m, v)                (((v) & (m)) >> MASK_LSH(m))
+#define MASK_LSH(m)            (__builtin_ffsl(m) - 1)
+#define SET_FIELD(m, v, val)   \
+		(((v) & ~(m)) | ((((typeof(v))(val)) << MASK_LSH(m)) & (m)))
+
+/*
+ * Co-processor Engine type.
+ */
+enum vas_cop_type {
+	VAS_COP_TYPE_FAULT,
+	VAS_COP_TYPE_842,
+	VAS_COP_TYPE_842_HIPRI,
+	VAS_COP_TYPE_GZIP,
+	VAS_COP_TYPE_GZIP_HIPRI,
+	VAS_COP_TYPE_FTW,
+	VAS_COP_TYPE_MAX,
+};
+
+/*
+ * User space VAS windows are opened by tasks and take references
+ * to pid and mm until windows are closed.
+ * Stores pid, mm, and tgid for each window.
+ */
+struct vas_user_win_ref {
+	struct pid *pid;	/* PID of owner */
+	struct pid *tgid;	/* Thread group ID of owner */
+	struct mm_struct *mm;	/* Linux process mm_struct */
+	struct mutex mmap_mutex;	/* protects paste address mmap() */
+					/* with DLPAR close/open windows */
+	struct vm_area_struct *vma;	/* Save VMA and used in DLPAR ops */
+};
+
+/*
+ * Common VAS window struct on PowerNV and PowerVM
+ */
+struct vas_window {
+	u32 winid;
+	u32 wcreds_max;	/* Window credits */
+	u32 status;	/* Window status used in OS */
+	enum vas_cop_type cop;
+	struct vas_user_win_ref task_ref;
+	char *dbgname;
+	struct dentry *dbgdir;
+};
+
+/*
+ * User space window operations used for powernv and powerVM
+ */
+struct vas_user_win_ops {
+	struct vas_window * (*open_win)(int vas_id, u64 flags,
+				enum vas_cop_type);
+	u64 (*paste_addr)(struct vas_window *);
+	int (*close_win)(struct vas_window *);
+};
+
+static inline void put_vas_user_win_ref(struct vas_user_win_ref *ref)
+{
+	/* Drop references to pid, tgid, and mm */
+	put_pid(ref->pid);
+	put_pid(ref->tgid);
+	if (ref->mm)
+		mmdrop(ref->mm);
+}
+
+static inline void vas_user_win_add_mm_context(struct vas_user_win_ref *ref)
+{
+	mm_context_add_vas_window(ref->mm);
+	/*
+	 * Even a process that has no foreign real address mapping can
+	 * use an unpaired COPY instruction (to no real effect). Issue
+	 * CP_ABORT to clear any pending COPY and prevent a covert
+	 * channel.
+	 *
+	 * __switch_to() will issue CP_ABORT on future context switches
+	 * if process / thread has any open VAS window (Use
+	 * current->mm->context.vas_windows).
+	 */
+	asm volatile(PPC_CP_ABORT);
+}
+
+/*
+ * Receive window attributes specified by the (in-kernel) owner of window.
+ */
+struct vas_rx_win_attr {
+	u64 rx_fifo;
+	int rx_fifo_size;
+	int wcreds_max;
+
+	bool pin_win;
+	bool rej_no_credit;
+	bool tx_wcred_mode;
+	bool rx_wcred_mode;
+	bool tx_win_ord_mode;
+	bool rx_win_ord_mode;
+	bool data_stamp;
+	bool nx_win;
+	bool fault_win;
+	bool user_win;
+	bool notify_disable;
+	bool intr_disable;
+	bool notify_early;
+
+	int lnotify_lpid;
+	int lnotify_pid;
+	int lnotify_tid;
+	u32 pswid;
+
+	int tc_mode;
+};
+
+/*
+ * Window attributes specified by the in-kernel owner of a send window.
+ */
+struct vas_tx_win_attr {
+	enum vas_cop_type cop;
+	int wcreds_max;
+	int lpid;
+	int pidr;		/* hardware PID (from SPRN_PID) */
+	int pswid;
+	int rsvd_txbuf_count;
+	int tc_mode;
+
+	bool user_win;
+	bool pin_win;
+	bool rej_no_credit;
+	bool rsvd_txbuf_enable;
+	bool tx_wcred_mode;
+	bool rx_wcred_mode;
+	bool tx_win_ord_mode;
+	bool rx_win_ord_mode;
+};
+
+#ifdef CONFIG_PPC_POWERNV
+/*
+ * Helper to map a chip id to VAS id.
+ * For POWER9, this is a 1:1 mapping. In the future this maybe a 1:N
+ * mapping in which case, we will need to update this helper.
+ *
+ * Return the VAS id or -1 if no matching vasid is found.
+ */
+int chip_to_vas_id(int chipid);
+
+/*
+ * Helper to initialize receive window attributes to defaults for an
+ * NX window.
+ */
+void vas_init_rx_win_attr(struct vas_rx_win_attr *rxattr, enum vas_cop_type cop);
+
+/*
+ * Open a VAS receive window for the instance of VAS identified by @vasid
+ * Use @attr to initialize the attributes of the window.
+ *
+ * Return a handle to the window or ERR_PTR() on error.
+ */
+struct vas_window *vas_rx_win_open(int vasid, enum vas_cop_type cop,
+				   struct vas_rx_win_attr *attr);
+
+/*
+ * Helper to initialize send window attributes to defaults for an NX window.
+ */
+extern void vas_init_tx_win_attr(struct vas_tx_win_attr *txattr,
+			enum vas_cop_type cop);
+
+/*
+ * Open a VAS send window for the instance of VAS identified by @vasid
+ * and the co-processor type @cop. Use @attr to initialize attributes
+ * of the window.
+ *
+ * Note: The instance of VAS must already have an open receive window for
+ * the coprocessor type @cop.
+ *
+ * Return a handle to the send window or ERR_PTR() on error.
+ */
+struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
+			struct vas_tx_win_attr *attr);
+
+/*
+ * Close the send or receive window identified by @win. For receive windows
+ * return -EAGAIN if there are active send windows attached to this receive
+ * window.
+ */
+int vas_win_close(struct vas_window *win);
+
+/*
+ * Copy the co-processor request block (CRB) @crb into the local L2 cache.
+ */
+int vas_copy_crb(void *crb, int offset);
+
+/*
+ * Paste a previously copied CRB (see vas_copy_crb()) from the L2 cache to
+ * the hardware address associated with the window @win. @re is expected/
+ * assumed to be true for NX windows.
+ */
+int vas_paste_crb(struct vas_window *win, int offset, bool re);
+
+int vas_register_api_powernv(struct module *mod, enum vas_cop_type cop_type,
+			     const char *name);
+void vas_unregister_api_powernv(void);
+#endif
+
+#ifdef CONFIG_PPC_PSERIES
+
+/* VAS Capabilities */
+#define VAS_GZIP_QOS_FEAT	0x1
+#define VAS_GZIP_DEF_FEAT	0x2
+#define VAS_GZIP_QOS_FEAT_BIT	PPC_BIT(VAS_GZIP_QOS_FEAT) /* Bit 1 */
+#define VAS_GZIP_DEF_FEAT_BIT	PPC_BIT(VAS_GZIP_DEF_FEAT) /* Bit 2 */
+
+/* NX Capabilities */
+#define VAS_NX_GZIP_FEAT	0x1
+#define VAS_NX_GZIP_FEAT_BIT	PPC_BIT(VAS_NX_GZIP_FEAT) /* Bit 1 */
+
+/*
+ * These structs are used to retrieve overall VAS capabilities that
+ * the hypervisor provides.
+ */
+struct hv_vas_all_caps {
+	__be64  descriptor;
+	__be64  feat_type;
+} __packed __aligned(0x1000);
+
+struct vas_all_caps {
+	u64     descriptor;
+	u64     feat_type;
+};
+
+int h_query_vas_capabilities(const u64 hcall, u8 query_type, u64 result);
+int vas_register_api_pseries(struct module *mod,
+			     enum vas_cop_type cop_type, const char *name);
+void vas_unregister_api_pseries(void);
+#endif
+
+/*
+ * 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, enum vas_cop_type cop_type,
+			    const char *name,
+			    const struct vas_user_win_ops *vops);
+void vas_unregister_coproc_api(void);
+
+int get_vas_user_win_ref(struct vas_user_win_ref *task_ref);
+void vas_update_csb(struct coprocessor_request_block *crb,
+		    struct vas_user_win_ref *task_ref);
+void vas_dump_crb(struct coprocessor_request_block *crb);
+#endif /* __ASM_POWERPC_VAS_H */