All of lore.kernel.org
 help / color / mirror / Atom feed
From: Toshi Kani <toshi.kani@hp.com>
To: akpm@linux-foundation.org, hpa@zytor.com, tglx@linutronix.de,
	mingo@redhat.com, arnd@arndb.de, linux-mm@kvack.org
Cc: x86@kernel.org, linux-kernel@vger.kernel.org,
	Toshi Kani <toshi.kani@hp.com>
Subject: [RFC PATCH 2/7] lib: Add huge I/O map capability interfaces
Date: Mon, 26 Jan 2015 16:13:24 -0700	[thread overview]
Message-ID: <1422314009-31667-3-git-send-email-toshi.kani@hp.com> (raw)
In-Reply-To: <1422314009-31667-1-git-send-email-toshi.kani@hp.com>

Add ioremap_pud_enabled() and ioremap_pmd_enabled(), which
return 1 when I/O mappings of pud/pmd are enabled on the kernel.

ioremap_huge_init() calls arch_ioremap_pud_supported() and
arch_ioremap_pmd_supported() to initialize the capabilities.

A new kernel option "nohgiomap" is also added, so that user can
disable the huge I/O map capabilities if necessary.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
---
 Documentation/kernel-parameters.txt |    2 ++
 include/linux/io.h                  |    5 ++++
 lib/ioremap.c                       |   44 +++++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 176d4fe..e3de01c 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2304,6 +2304,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			register save and restore. The kernel will only save
 			legacy floating-point registers on task switch.
 
+	nohgiomap	[KNL,x86] Disable huge I/O mappings.
+
 	noxsave		[BUGS=X86] Disables x86 extended register state save
 			and restore using xsave. The kernel will fallback to
 			enabling legacy floating-point and sse state.
diff --git a/include/linux/io.h b/include/linux/io.h
index fa02e55..8f5c8af 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -38,6 +38,11 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end,
 }
 #endif
 
+#ifdef CONFIG_HUGE_IOMAP
+int arch_ioremap_pud_supported(void);
+int arch_ioremap_pmd_supported(void);
+#endif
+
 /*
  * Managed iomap interface
  */
diff --git a/lib/ioremap.c b/lib/ioremap.c
index 0c9216c..0a1ecb6 100644
--- a/lib/ioremap.c
+++ b/lib/ioremap.c
@@ -13,6 +13,44 @@
 #include <asm/cacheflush.h>
 #include <asm/pgtable.h>
 
+#ifdef CONFIG_HUGE_IOMAP
+int __read_mostly ioremap_pud_capable;
+int __read_mostly ioremap_pmd_capable;
+int __read_mostly ioremap_huge_disabled;
+
+static int __init set_nohgiomap(char *str)
+{
+	ioremap_huge_disabled = 1;
+	return 0;
+}
+early_param("nohgiomap", set_nohgiomap);
+
+static inline void ioremap_huge_init(void)
+{
+	if (!ioremap_huge_disabled) {
+		if (arch_ioremap_pud_supported())
+			ioremap_pud_capable = 1;
+		if (arch_ioremap_pmd_supported())
+			ioremap_pmd_capable = 1;
+	}
+}
+
+static inline int ioremap_pud_enabled(void)
+{
+	return ioremap_pud_capable;
+}
+
+static inline int ioremap_pmd_enabled(void)
+{
+	return ioremap_pmd_capable;
+}
+
+#else	/* !CONFIG_HUGE_IOMAP */
+static inline void ioremap_huge_init(void) { }
+static inline int ioremap_pud_enabled(void) { return 0; }
+static inline int ioremap_pmd_enabled(void) { return 0; }
+#endif	/* CONFIG_HUGE_IOMAP */
+
 static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
 		unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
 {
@@ -74,6 +112,12 @@ int ioremap_page_range(unsigned long addr,
 	unsigned long start;
 	unsigned long next;
 	int err;
+	static int ioremap_huge_init_done;
+
+	if (!ioremap_huge_init_done) {
+		ioremap_huge_init_done = 1;
+		ioremap_huge_init();
+	}
 
 	BUG_ON(addr >= end);
 

WARNING: multiple messages have this Message-ID (diff)
From: Toshi Kani <toshi.kani@hp.com>
To: akpm@linux-foundation.org, hpa@zytor.com, tglx@linutronix.de,
	mingo@redhat.com, arnd@arndb.de, linux-mm@kvack.org
Cc: x86@kernel.org, linux-kernel@vger.kernel.org,
	Toshi Kani <toshi.kani@hp.com>
Subject: [RFC PATCH 2/7] lib: Add huge I/O map capability interfaces
Date: Mon, 26 Jan 2015 16:13:24 -0700	[thread overview]
Message-ID: <1422314009-31667-3-git-send-email-toshi.kani@hp.com> (raw)
In-Reply-To: <1422314009-31667-1-git-send-email-toshi.kani@hp.com>

Add ioremap_pud_enabled() and ioremap_pmd_enabled(), which
return 1 when I/O mappings of pud/pmd are enabled on the kernel.

ioremap_huge_init() calls arch_ioremap_pud_supported() and
arch_ioremap_pmd_supported() to initialize the capabilities.

A new kernel option "nohgiomap" is also added, so that user can
disable the huge I/O map capabilities if necessary.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
---
 Documentation/kernel-parameters.txt |    2 ++
 include/linux/io.h                  |    5 ++++
 lib/ioremap.c                       |   44 +++++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 176d4fe..e3de01c 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2304,6 +2304,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			register save and restore. The kernel will only save
 			legacy floating-point registers on task switch.
 
+	nohgiomap	[KNL,x86] Disable huge I/O mappings.
+
 	noxsave		[BUGS=X86] Disables x86 extended register state save
 			and restore using xsave. The kernel will fallback to
 			enabling legacy floating-point and sse state.
diff --git a/include/linux/io.h b/include/linux/io.h
index fa02e55..8f5c8af 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -38,6 +38,11 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end,
 }
 #endif
 
+#ifdef CONFIG_HUGE_IOMAP
+int arch_ioremap_pud_supported(void);
+int arch_ioremap_pmd_supported(void);
+#endif
+
 /*
  * Managed iomap interface
  */
diff --git a/lib/ioremap.c b/lib/ioremap.c
index 0c9216c..0a1ecb6 100644
--- a/lib/ioremap.c
+++ b/lib/ioremap.c
@@ -13,6 +13,44 @@
 #include <asm/cacheflush.h>
 #include <asm/pgtable.h>
 
+#ifdef CONFIG_HUGE_IOMAP
+int __read_mostly ioremap_pud_capable;
+int __read_mostly ioremap_pmd_capable;
+int __read_mostly ioremap_huge_disabled;
+
+static int __init set_nohgiomap(char *str)
+{
+	ioremap_huge_disabled = 1;
+	return 0;
+}
+early_param("nohgiomap", set_nohgiomap);
+
+static inline void ioremap_huge_init(void)
+{
+	if (!ioremap_huge_disabled) {
+		if (arch_ioremap_pud_supported())
+			ioremap_pud_capable = 1;
+		if (arch_ioremap_pmd_supported())
+			ioremap_pmd_capable = 1;
+	}
+}
+
+static inline int ioremap_pud_enabled(void)
+{
+	return ioremap_pud_capable;
+}
+
+static inline int ioremap_pmd_enabled(void)
+{
+	return ioremap_pmd_capable;
+}
+
+#else	/* !CONFIG_HUGE_IOMAP */
+static inline void ioremap_huge_init(void) { }
+static inline int ioremap_pud_enabled(void) { return 0; }
+static inline int ioremap_pmd_enabled(void) { return 0; }
+#endif	/* CONFIG_HUGE_IOMAP */
+
 static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
 		unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
 {
@@ -74,6 +112,12 @@ int ioremap_page_range(unsigned long addr,
 	unsigned long start;
 	unsigned long next;
 	int err;
+	static int ioremap_huge_init_done;
+
+	if (!ioremap_huge_init_done) {
+		ioremap_huge_init_done = 1;
+		ioremap_huge_init();
+	}
 
 	BUG_ON(addr >= end);
 

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  parent reply	other threads:[~2015-01-26 23:31 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-01-26 23:13 [RFC PATCH 0/7] Kernel huge I/O mapping support Toshi Kani
2015-01-26 23:13 ` Toshi Kani
2015-01-26 23:13 ` [RFC PATCH 1/7] mm: Change __get_vm_area_node() to use fls_long() Toshi Kani
2015-01-26 23:13   ` Toshi Kani
2015-01-26 23:13 ` Toshi Kani [this message]
2015-01-26 23:13   ` [RFC PATCH 2/7] lib: Add huge I/O map capability interfaces Toshi Kani
2015-01-26 23:54   ` Andrew Morton
2015-01-26 23:54     ` Andrew Morton
2015-01-27  1:01     ` Toshi Kani
2015-01-27  1:01       ` Toshi Kani
2015-01-27 21:37       ` Andrew Morton
2015-01-27 21:37         ` Andrew Morton
2015-01-27 22:01         ` Toshi Kani
2015-01-27 22:01           ` Toshi Kani
2015-02-05 20:56       ` Toshi Kani
2015-02-05 20:56         ` Toshi Kani
2015-01-26 23:13 ` [RFC PATCH 3/7] mm: Change ioremap to set up huge I/O mappings Toshi Kani
2015-01-26 23:13   ` Toshi Kani
2015-01-26 23:58   ` Andrew Morton
2015-01-26 23:58     ` Andrew Morton
2015-01-27  0:01     ` Toshi Kani
2015-01-27  0:01       ` Toshi Kani
2015-01-26 23:13 ` [RFC PATCH 4/7] mm: Change vunmap to tear down huge KVA mappings Toshi Kani
2015-01-26 23:13   ` Toshi Kani
2015-01-26 23:13 ` [RFC PATCH 5/7] x86, mm: Support huge KVA mappings on x86 Toshi Kani
2015-01-26 23:13   ` Toshi Kani
2015-01-26 23:13 ` [RFC PATCH 6/7] x86, mm: Support huge I/O " Toshi Kani
2015-01-26 23:13   ` Toshi Kani
2015-01-26 23:13 ` [RFC PATCH 7/7] mm: Add config HUGE_IOMAP to enable huge I/O mappings Toshi Kani
2015-01-26 23:13   ` Toshi Kani

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1422314009-31667-3-git-send-email-toshi.kani@hp.com \
    --to=toshi.kani@hp.com \
    --cc=akpm@linux-foundation.org \
    --cc=arnd@arndb.de \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mingo@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.