diff mbox series

[v4,1/3] md: Move sb writer loop to its own function

Message ID 20230223195225.534-2-jonathan.derrick@linux.dev (mailing list archive)
State Superseded, archived
Headers show
Series md/bitmap: Optimal last page size | expand

Commit Message

Jonathan Derrick Feb. 23, 2023, 7:52 p.m. UTC
From: Jon Derrick <jonathan.derrick@linux.dev>

Preparatory patch for optimal I/O size calculation. Move the sb writer
loop routine into its own function for clarity.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jon Derrick <jonathan.derrick@linux.dev>
---
 drivers/md/md-bitmap.c | 124 +++++++++++++++++++++--------------------
 1 file changed, 64 insertions(+), 60 deletions(-)

Comments

kernel test robot Feb. 24, 2023, 7:23 a.m. UTC | #1
Hi Jonathan,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on song-md/md-next]
[also build test WARNING on linus/master v6.2 next-20230224]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Jonathan-Derrick/md-Move-sb-writer-loop-to-its-own-function/20230224-035451
base:   git://git.kernel.org/pub/scm/linux/kernel/git/song/md.git md-next
patch link:    https://lore.kernel.org/r/20230223195225.534-2-jonathan.derrick%40linux.dev
patch subject: [PATCH v4 1/3] md: Move sb writer loop to its own function
config: s390-randconfig-r036-20230223 (https://download.01.org/0day-ci/archive/20230224/202302241507.7JQRJLLW-lkp@intel.com/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project db89896bbbd2251fff457699635acbbedeead27f)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install s390 cross compiling tool for clang build
        # apt-get install binutils-s390x-linux-gnu
        # https://github.com/intel-lab-lkp/linux/commit/93818e631c76938f9a3ad87d1baf681645d02ba7
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Jonathan-Derrick/md-Move-sb-writer-loop-to-its-own-function/20230224-035451
        git checkout 93818e631c76938f9a3ad87d1baf681645d02ba7
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202302241507.7JQRJLLW-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from drivers/md/md-bitmap.c:31:
   In file included from include/trace/events/block.h:8:
   In file included from include/linux/blktrace_api.h:5:
   In file included from include/linux/blk-mq.h:8:
   In file included from include/linux/scatterlist.h:9:
   In file included from arch/s390/include/asm/io.h:75:
   include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           val = __raw_readb(PCI_IOBASE + addr);
                             ~~~~~~~~~~ ^
   include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
                                                           ~~~~~~~~~~ ^
   include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu'
   #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
                                                             ^
   include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
   #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
                                                        ^
   In file included from drivers/md/md-bitmap.c:31:
   In file included from include/trace/events/block.h:8:
   In file included from include/linux/blktrace_api.h:5:
   In file included from include/linux/blk-mq.h:8:
   In file included from include/linux/scatterlist.h:9:
   In file included from arch/s390/include/asm/io.h:75:
   include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
                                                           ~~~~~~~~~~ ^
   include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu'
   #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
                                                             ^
   include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
   #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
                                                        ^
   In file included from drivers/md/md-bitmap.c:31:
   In file included from include/trace/events/block.h:8:
   In file included from include/linux/blktrace_api.h:5:
   In file included from include/linux/blk-mq.h:8:
   In file included from include/linux/scatterlist.h:9:
   In file included from arch/s390/include/asm/io.h:75:
   include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           __raw_writeb(value, PCI_IOBASE + addr);
                               ~~~~~~~~~~ ^
   include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
                                                         ~~~~~~~~~~ ^
   include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
                                                         ~~~~~~~~~~ ^
   include/asm-generic/io.h:692:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           readsb(PCI_IOBASE + addr, buffer, count);
                  ~~~~~~~~~~ ^
   include/asm-generic/io.h:700:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           readsw(PCI_IOBASE + addr, buffer, count);
                  ~~~~~~~~~~ ^
   include/asm-generic/io.h:708:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           readsl(PCI_IOBASE + addr, buffer, count);
                  ~~~~~~~~~~ ^
   include/asm-generic/io.h:717:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           writesb(PCI_IOBASE + addr, buffer, count);
                   ~~~~~~~~~~ ^
   include/asm-generic/io.h:726:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           writesw(PCI_IOBASE + addr, buffer, count);
                   ~~~~~~~~~~ ^
   include/asm-generic/io.h:735:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           writesl(PCI_IOBASE + addr, buffer, count);
                   ~~~~~~~~~~ ^
>> drivers/md/md-bitmap.c:273:18: warning: variable 'rdev' is used uninitialized whenever function 'write_sb_page' is called [-Wsometimes-uninitialized]
           struct md_rdev *rdev;
           ~~~~~~~~~~~~~~~~^~~~
   drivers/md/md-bitmap.c:278:35: note: uninitialized use occurs here
                   while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
                                                   ^~~~
   drivers/md/md-bitmap.c:273:22: note: initialize the variable 'rdev' to silence this warning
           struct md_rdev *rdev;
                               ^
                                = NULL
   13 warnings generated.


vim +273 drivers/md/md-bitmap.c

   270	
   271	static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
   272	{
 > 273		struct md_rdev *rdev;
   274		struct mddev *mddev = bitmap->mddev;
   275		int ret;
   276	
   277		do {
   278			while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
   279				ret = __write_sb_page(rdev, bitmap, page);
   280				if (ret)
   281					return ret;
   282			}
   283		} while (wait && md_super_wait(mddev) < 0);
   284	
   285		return 0;
   286	}
   287
Jonathan Derrick Feb. 24, 2023, 6:27 p.m. UTC | #2
On 2/24/2023 12:23 AM, kernel test robot wrote:
> Hi Jonathan,
> 
> Thank you for the patch! Perhaps something to improve:
> 
> [auto build test WARNING on song-md/md-next]
> [also build test WARNING on linus/master v6.2 next-20230224]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Jonathan-Derrick/md-Move-sb-writer-loop-to-its-own-function/20230224-035451
> base:   git://git.kernel.org/pub/scm/linux/kernel/git/song/md.git md-next
> patch link:    https://lore.kernel.org/r/20230223195225.534-2-jonathan.derrick%40linux.dev
> patch subject: [PATCH v4 1/3] md: Move sb writer loop to its own function
> config: s390-randconfig-r036-20230223 (https://download.01.org/0day-ci/archive/20230224/202302241507.7JQRJLLW-lkp@intel.com/config)
> compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project db89896bbbd2251fff457699635acbbedeead27f)
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # install s390 cross compiling tool for clang build
>         # apt-get install binutils-s390x-linux-gnu
>         # https://github.com/intel-lab-lkp/linux/commit/93818e631c76938f9a3ad87d1baf681645d02ba7
>         git remote add linux-review https://github.com/intel-lab-lkp/linux
>         git fetch --no-tags linux-review Jonathan-Derrick/md-Move-sb-writer-loop-to-its-own-function/20230224-035451
>         git checkout 93818e631c76938f9a3ad87d1baf681645d02ba7
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 olddefconfig
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash
> 
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
> | Link: https://lore.kernel.org/oe-kbuild-all/202302241507.7JQRJLLW-lkp@intel.com/
> 
> All warnings (new ones prefixed by >>):
> 
>    In file included from drivers/md/md-bitmap.c:31:
>    In file included from include/trace/events/block.h:8:
>    In file included from include/linux/blktrace_api.h:5:
>    In file included from include/linux/blk-mq.h:8:
>    In file included from include/linux/scatterlist.h:9:
>    In file included from arch/s390/include/asm/io.h:75:
>    include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            val = __raw_readb(PCI_IOBASE + addr);
>                              ~~~~~~~~~~ ^
>    include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
>                                                            ~~~~~~~~~~ ^
>    include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu'
>    #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
>                                                              ^
>    include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
>    #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
>                                                         ^
>    In file included from drivers/md/md-bitmap.c:31:
>    In file included from include/trace/events/block.h:8:
>    In file included from include/linux/blktrace_api.h:5:
>    In file included from include/linux/blk-mq.h:8:
>    In file included from include/linux/scatterlist.h:9:
>    In file included from arch/s390/include/asm/io.h:75:
>    include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
>                                                            ~~~~~~~~~~ ^
>    include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu'
>    #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
>                                                              ^
>    include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
>    #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
>                                                         ^
>    In file included from drivers/md/md-bitmap.c:31:
>    In file included from include/trace/events/block.h:8:
>    In file included from include/linux/blktrace_api.h:5:
>    In file included from include/linux/blk-mq.h:8:
>    In file included from include/linux/scatterlist.h:9:
>    In file included from arch/s390/include/asm/io.h:75:
>    include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            __raw_writeb(value, PCI_IOBASE + addr);
>                                ~~~~~~~~~~ ^
>    include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
>                                                          ~~~~~~~~~~ ^
>    include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
>                                                          ~~~~~~~~~~ ^
>    include/asm-generic/io.h:692:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            readsb(PCI_IOBASE + addr, buffer, count);
>                   ~~~~~~~~~~ ^
>    include/asm-generic/io.h:700:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            readsw(PCI_IOBASE + addr, buffer, count);
>                   ~~~~~~~~~~ ^
>    include/asm-generic/io.h:708:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            readsl(PCI_IOBASE + addr, buffer, count);
>                   ~~~~~~~~~~ ^
>    include/asm-generic/io.h:717:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            writesb(PCI_IOBASE + addr, buffer, count);
>                    ~~~~~~~~~~ ^
>    include/asm-generic/io.h:726:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            writesw(PCI_IOBASE + addr, buffer, count);
>                    ~~~~~~~~~~ ^
>    include/asm-generic/io.h:735:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>            writesl(PCI_IOBASE + addr, buffer, count);
>                    ~~~~~~~~~~ ^
>>> drivers/md/md-bitmap.c:273:18: warning: variable 'rdev' is used uninitialized whenever function 'write_sb_page' is called [-Wsometimes-uninitialized]
>            struct md_rdev *rdev;
>            ~~~~~~~~~~~~~~~~^~~~
>    drivers/md/md-bitmap.c:278:35: note: uninitialized use occurs here
>                    while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
>                                                    ^~~~
>    drivers/md/md-bitmap.c:273:22: note: initialize the variable 'rdev' to silence this warning
Oops, I missed the rdev = NULL;
V5 incoming

>            struct md_rdev *rdev;
>                                ^
>                                 = NULL
>    13 warnings generated.
> 
> 
> vim +273 drivers/md/md-bitmap.c
> 
>    270	
>    271	static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
>    272	{
>  > 273		struct md_rdev *rdev;
>    274		struct mddev *mddev = bitmap->mddev;
>    275		int ret;
>    276	
>    277		do {
>    278			while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
>    279				ret = __write_sb_page(rdev, bitmap, page);
>    280				if (ret)
>    281					return ret;
>    282			}
>    283		} while (wait && md_super_wait(mddev) < 0);
>    284	
>    285		return 0;
>    286	}
>    287	
>
diff mbox series

Patch

diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index e7cc6ba1b657..2d161d24c51c 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -209,76 +209,80 @@  static struct md_rdev *next_active_rdev(struct md_rdev *rdev, struct mddev *mdde
 	return NULL;
 }
 
-static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
+static int __write_sb_page(struct md_rdev *rdev, struct bitmap *bitmap,
+			   struct page *page)
 {
-	struct md_rdev *rdev;
 	struct block_device *bdev;
 	struct mddev *mddev = bitmap->mddev;
 	struct bitmap_storage *store = &bitmap->storage;
+	loff_t offset = mddev->bitmap_info.offset;
+	int size = PAGE_SIZE;
+
+	bdev = (rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev;
+	if (page->index == store->file_pages - 1) {
+		int last_page_size = store->bytes & (PAGE_SIZE - 1);
+
+		if (last_page_size == 0)
+			last_page_size = PAGE_SIZE;
+		size = roundup(last_page_size,
+			       bdev_logical_block_size(bdev));
+	}
+
+	/* Just make sure we aren't corrupting data or metadata */
+	if (mddev->external) {
+		/* Bitmap could be anywhere. */
+		if (rdev->sb_start + offset
+		    + (page->index * (PAGE_SIZE / SECTOR_SIZE))
+		    > rdev->data_offset &&
+		    rdev->sb_start + offset
+		    < (rdev->data_offset + mddev->dev_sectors
+		     + (PAGE_SIZE / SECTOR_SIZE)))
+			return -EINVAL;
+	} else if (offset < 0) {
+		/* DATA  BITMAP METADATA  */
+		if (offset
+		    + (long)(page->index * (PAGE_SIZE / SECTOR_SIZE))
+		    + size / SECTOR_SIZE > 0)
+			/* bitmap runs in to metadata */
+			return -EINVAL;
+
+		if (rdev->data_offset + mddev->dev_sectors
+		    > rdev->sb_start + offset)
+			/* data runs in to bitmap */
+			return -EINVAL;
+	} else if (rdev->sb_start < rdev->data_offset) {
+		/* METADATA BITMAP DATA */
+		if (rdev->sb_start + offset
+		    + page->index * (PAGE_SIZE / SECTOR_SIZE)
+		    + size / SECTOR_SIZE > rdev->data_offset)
+			/* bitmap runs in to data */
+			return -EINVAL;
+	} else {
+		/* DATA METADATA BITMAP - no problems */
+	}
 
-restart:
-	rdev = NULL;
-	while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
-		int size = PAGE_SIZE;
-		loff_t offset = mddev->bitmap_info.offset;
+	md_super_write(mddev, rdev,
+		       rdev->sb_start + offset
+		       + page->index * (PAGE_SIZE / SECTOR_SIZE),
+		       size, page);
+	return 0;
+}
 
-		bdev = (rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev;
+static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
+{
+	struct md_rdev *rdev;
+	struct mddev *mddev = bitmap->mddev;
+	int ret;
 
-		if (page->index == store->file_pages-1) {
-			int last_page_size = store->bytes & (PAGE_SIZE-1);
-			if (last_page_size == 0)
-				last_page_size = PAGE_SIZE;
-			size = roundup(last_page_size,
-				       bdev_logical_block_size(bdev));
-		}
-		/* Just make sure we aren't corrupting data or
-		 * metadata
-		 */
-		if (mddev->external) {
-			/* Bitmap could be anywhere. */
-			if (rdev->sb_start + offset + (page->index
-						       * (PAGE_SIZE/512))
-			    > rdev->data_offset
-			    &&
-			    rdev->sb_start + offset
-			    < (rdev->data_offset + mddev->dev_sectors
-			     + (PAGE_SIZE/512)))
-				goto bad_alignment;
-		} else if (offset < 0) {
-			/* DATA  BITMAP METADATA  */
-			if (offset
-			    + (long)(page->index * (PAGE_SIZE/512))
-			    + size/512 > 0)
-				/* bitmap runs in to metadata */
-				goto bad_alignment;
-			if (rdev->data_offset + mddev->dev_sectors
-			    > rdev->sb_start + offset)
-				/* data runs in to bitmap */
-				goto bad_alignment;
-		} else if (rdev->sb_start < rdev->data_offset) {
-			/* METADATA BITMAP DATA */
-			if (rdev->sb_start
-			    + offset
-			    + page->index*(PAGE_SIZE/512) + size/512
-			    > rdev->data_offset)
-				/* bitmap runs in to data */
-				goto bad_alignment;
-		} else {
-			/* DATA METADATA BITMAP - no problems */
+	do {
+		while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
+			ret = __write_sb_page(rdev, bitmap, page);
+			if (ret)
+				return ret;
 		}
-		md_super_write(mddev, rdev,
-			       rdev->sb_start + offset
-			       + page->index * (PAGE_SIZE/512),
-			       size,
-			       page);
-	}
+	} while (wait && md_super_wait(mddev) < 0);
 
-	if (wait && md_super_wait(mddev) < 0)
-		goto restart;
 	return 0;
-
- bad_alignment:
-	return -EINVAL;
 }
 
 static void md_bitmap_file_kick(struct bitmap *bitmap);