| Message ID | 149433927812.2049.3430917601443895174.stgit@dwillia2-desk3.amr.corp.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue 09-05-17 07:17:04, Dan Williams wrote: > For configurations that do not enable DAX filesystems or drivers, do not > require the DAX core to be built. > > Given that the 'direct_access' method has been removed from > 'block_device_operations', we can also go ahead and remove the > block-related dax helper functions from fs/block_dev.c to > drivers/dax/super.c. This keeps dax details out of the block layer and > lets the DAX core be built as a module in the FS_DAX=n case. > > Filesystems need to include dax.h to call bdev_dax_supported(). > > Cc: Jan Kara <jack@suse.com> > Cc: linux-xfs@vger.kernel.org > Cc: Jens Axboe <axboe@kernel.dk> > Cc: "Theodore Ts'o" <tytso@mit.edu> > Cc: Matthew Wilcox <mawilcox@microsoft.com> > Cc: Alexander Viro <viro@zeniv.linux.org.uk> > Cc: "Darrick J. Wong" <darrick.wong@oracle.com> > Cc: Ross Zwisler <ross.zwisler@linux.intel.com> > Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> > Signed-off-by: Dan Williams <dan.j.williams@intel.com> Looks good to me. You can add: Reviewed-by: Jan Kara <jack@suse.cz> Honza > --- > Changes in v2: > * kill off the remainder of the dax specific routines in the block layer > and move it to the drivers/dax core. > > block/Kconfig | 1 - > drivers/dax/super.c | 70 ++++++++++++++++++++++++++++++++++++++++++++++++ > fs/Kconfig | 1 + > fs/block_dev.c | 66 --------------------------------------------- > fs/ext2/super.c | 1 + > fs/ext4/super.c | 1 + > fs/xfs/xfs_super.c | 1 + > include/linux/blkdev.h | 2 - > include/linux/dax.h | 30 +++++++++++++++++++-- > 9 files changed, 102 insertions(+), 71 deletions(-) > > diff --git a/block/Kconfig b/block/Kconfig > index 93da7fc3f254..e9f780f815f5 100644 > --- a/block/Kconfig > +++ b/block/Kconfig > @@ -6,7 +6,6 @@ menuconfig BLOCK > default y > select SBITMAP > select SRCU > - select DAX > help > Provide block layer support for the kernel. > > diff --git a/drivers/dax/super.c b/drivers/dax/super.c > index 465dcd7317d5..e8998d15f3cd 100644 > --- a/drivers/dax/super.c > +++ b/drivers/dax/super.c > @@ -14,6 +14,7 @@ > #include <linux/module.h> > #include <linux/mount.h> > #include <linux/magic.h> > +#include <linux/genhd.h> > #include <linux/cdev.h> > #include <linux/hash.h> > #include <linux/slab.h> > @@ -47,6 +48,75 @@ void dax_read_unlock(int id) > } > EXPORT_SYMBOL_GPL(dax_read_unlock); > > +int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size, > + pgoff_t *pgoff) > +{ > + phys_addr_t phys_off = (get_start_sect(bdev) + sector) * 512; > + > + if (pgoff) > + *pgoff = PHYS_PFN(phys_off); > + if (phys_off % PAGE_SIZE || size % PAGE_SIZE) > + return -EINVAL; > + return 0; > +} > +EXPORT_SYMBOL(bdev_dax_pgoff); > + > +/** > + * __bdev_dax_supported() - Check if the device supports dax for filesystem > + * @sb: The superblock of the device > + * @blocksize: The block size of the device > + * > + * This is a library function for filesystems to check if the block device > + * can be mounted with dax option. > + * > + * Return: negative errno if unsupported, 0 if supported. > + */ > +int __bdev_dax_supported(struct super_block *sb, int blocksize) > +{ > + struct block_device *bdev = sb->s_bdev; > + struct dax_device *dax_dev; > + pgoff_t pgoff; > + int err, id; > + void *kaddr; > + pfn_t pfn; > + long len; > + > + if (blocksize != PAGE_SIZE) { > + pr_err("VFS (%s): error: unsupported blocksize for dax\n", > + sb->s_id); > + return -EINVAL; > + } > + > + err = bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff); > + if (err) { > + pr_err("VFS (%s): error: unaligned partition for dax\n", > + sb->s_id); > + return err; > + } > + > + dax_dev = dax_get_by_host(bdev->bd_disk->disk_name); > + if (!dax_dev) { > + pr_err("VFS (%s): error: device does not support dax\n", > + sb->s_id); > + return -EOPNOTSUPP; > + } > + > + id = dax_read_lock(); > + len = dax_direct_access(dax_dev, pgoff, 1, &kaddr, &pfn); > + dax_read_unlock(id); > + > + put_dax(dax_dev); > + > + if (len < 1) { > + pr_err("VFS (%s): error: dax access failed (%ld)", > + sb->s_id, len); > + return len < 0 ? len : -EIO; > + } > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(__bdev_dax_supported); > + > /** > * struct dax_device - anchor object for dax services > * @inode: core vfs > diff --git a/fs/Kconfig b/fs/Kconfig > index 83eab52fb3f6..b0e42b6a96b9 100644 > --- a/fs/Kconfig > +++ b/fs/Kconfig > @@ -39,6 +39,7 @@ config FS_DAX > depends on MMU > depends on !(ARM || MIPS || SPARC) > select FS_IOMAP > + select DAX > help > Direct Access (DAX) can be used on memory-backed block devices. > If the block device supports DAX and the filesystem supports DAX, > diff --git a/fs/block_dev.c b/fs/block_dev.c > index 666367e13711..3096ecd48304 100644 > --- a/fs/block_dev.c > +++ b/fs/block_dev.c > @@ -718,72 +718,6 @@ int bdev_write_page(struct block_device *bdev, sector_t sector, > } > EXPORT_SYMBOL_GPL(bdev_write_page); > > -int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size, > - pgoff_t *pgoff) > -{ > - phys_addr_t phys_off = (get_start_sect(bdev) + sector) * 512; > - > - if (pgoff) > - *pgoff = PHYS_PFN(phys_off); > - if (phys_off % PAGE_SIZE || size % PAGE_SIZE) > - return -EINVAL; > - return 0; > -} > -EXPORT_SYMBOL(bdev_dax_pgoff); > - > -/** > - * bdev_dax_supported() - Check if the device supports dax for filesystem > - * @sb: The superblock of the device > - * @blocksize: The block size of the device > - * > - * This is a library function for filesystems to check if the block device > - * can be mounted with dax option. > - * > - * Return: negative errno if unsupported, 0 if supported. > - */ > -int bdev_dax_supported(struct super_block *sb, int blocksize) > -{ > - struct block_device *bdev = sb->s_bdev; > - struct dax_device *dax_dev; > - pgoff_t pgoff; > - int err, id; > - void *kaddr; > - pfn_t pfn; > - long len; > - > - if (blocksize != PAGE_SIZE) { > - vfs_msg(sb, KERN_ERR, "error: unsupported blocksize for dax"); > - return -EINVAL; > - } > - > - err = bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff); > - if (err) { > - vfs_msg(sb, KERN_ERR, "error: unaligned partition for dax"); > - return err; > - } > - > - dax_dev = dax_get_by_host(bdev->bd_disk->disk_name); > - if (!dax_dev) { > - vfs_msg(sb, KERN_ERR, "error: device does not support dax"); > - return -EOPNOTSUPP; > - } > - > - id = dax_read_lock(); > - len = dax_direct_access(dax_dev, pgoff, 1, &kaddr, &pfn); > - dax_read_unlock(id); > - > - put_dax(dax_dev); > - > - if (len < 1) { > - vfs_msg(sb, KERN_ERR, > - "error: dax access failed (%ld)", len); > - return len < 0 ? len : -EIO; > - } > - > - return 0; > -} > -EXPORT_SYMBOL_GPL(bdev_dax_supported); > - > /* > * pseudo-fs > */ > diff --git a/fs/ext2/super.c b/fs/ext2/super.c > index 9e25a71fe1a2..d07773b81da9 100644 > --- a/fs/ext2/super.c > +++ b/fs/ext2/super.c > @@ -32,6 +32,7 @@ > #include <linux/log2.h> > #include <linux/quotaops.h> > #include <linux/uaccess.h> > +#include <linux/dax.h> > #include "ext2.h" > #include "xattr.h" > #include "acl.h" > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > index a9448db1cf7e..bf6bb8997124 100644 > --- a/fs/ext4/super.c > +++ b/fs/ext4/super.c > @@ -37,6 +37,7 @@ > #include <linux/ctype.h> > #include <linux/log2.h> > #include <linux/crc16.h> > +#include <linux/dax.h> > #include <linux/cleancache.h> > #include <linux/uaccess.h> > > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c > index 685c042a120f..f5c58d6dcafb 100644 > --- a/fs/xfs/xfs_super.c > +++ b/fs/xfs/xfs_super.c > @@ -52,6 +52,7 @@ > #include "xfs_reflink.h" > > #include <linux/namei.h> > +#include <linux/dax.h> > #include <linux/init.h> > #include <linux/slab.h> > #include <linux/mount.h> > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index 848f87eb1905..e4d9899755a7 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -1940,8 +1940,6 @@ extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, > extern int bdev_read_page(struct block_device *, sector_t, struct page *); > extern int bdev_write_page(struct block_device *, sector_t, struct page *, > struct writeback_control *); > -extern int bdev_dax_supported(struct super_block *, int); > -int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff); > #else /* CONFIG_BLOCK */ > > struct block_device; > diff --git a/include/linux/dax.h b/include/linux/dax.h > index d3158e74a59e..7fdf1d710042 100644 > --- a/include/linux/dax.h > +++ b/include/linux/dax.h > @@ -18,12 +18,38 @@ struct dax_operations { > void **, pfn_t *); > }; > > +int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff); > +#if IS_ENABLED(CONFIG_FS_DAX) > +int __bdev_dax_supported(struct super_block *sb, int blocksize); > +static inline int bdev_dax_supported(struct super_block *sb, int blocksize) > +{ > + return __bdev_dax_supported(sb, blocksize); > +} > +#else > +static inline int bdev_dax_supported(struct super_block *sb, int blocksize) > +{ > + return -EOPNOTSUPP; > +} > +#endif > + > +#if IS_ENABLED(CONFIG_DAX) > +struct dax_device *dax_get_by_host(const char *host); > +void put_dax(struct dax_device *dax_dev); > +#else > +static inline struct dax_device *dax_get_by_host(const char *host) > +{ > + return NULL; > +} > + > +static inline void put_dax(struct dax_device *dax_dev) > +{ > +} > +#endif > + > int dax_read_lock(void); > void dax_read_unlock(int id); > -struct dax_device *dax_get_by_host(const char *host); > struct dax_device *alloc_dax(void *private, const char *host, > const struct dax_operations *ops); > -void put_dax(struct dax_device *dax_dev); > bool dax_alive(struct dax_device *dax_dev); > void kill_dax(struct dax_device *dax_dev); > void *dax_get_private(struct dax_device *dax_dev); > >
diff --git a/block/Kconfig b/block/Kconfig index 93da7fc3f254..e9f780f815f5 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -6,7 +6,6 @@ menuconfig BLOCK default y select SBITMAP select SRCU - select DAX help Provide block layer support for the kernel. diff --git a/drivers/dax/super.c b/drivers/dax/super.c index 465dcd7317d5..e8998d15f3cd 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -14,6 +14,7 @@ #include <linux/module.h> #include <linux/mount.h> #include <linux/magic.h> +#include <linux/genhd.h> #include <linux/cdev.h> #include <linux/hash.h> #include <linux/slab.h> @@ -47,6 +48,75 @@ void dax_read_unlock(int id) } EXPORT_SYMBOL_GPL(dax_read_unlock); +int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size, + pgoff_t *pgoff) +{ + phys_addr_t phys_off = (get_start_sect(bdev) + sector) * 512; + + if (pgoff) + *pgoff = PHYS_PFN(phys_off); + if (phys_off % PAGE_SIZE || size % PAGE_SIZE) + return -EINVAL; + return 0; +} +EXPORT_SYMBOL(bdev_dax_pgoff); + +/** + * __bdev_dax_supported() - Check if the device supports dax for filesystem + * @sb: The superblock of the device + * @blocksize: The block size of the device + * + * This is a library function for filesystems to check if the block device + * can be mounted with dax option. + * + * Return: negative errno if unsupported, 0 if supported. + */ +int __bdev_dax_supported(struct super_block *sb, int blocksize) +{ + struct block_device *bdev = sb->s_bdev; + struct dax_device *dax_dev; + pgoff_t pgoff; + int err, id; + void *kaddr; + pfn_t pfn; + long len; + + if (blocksize != PAGE_SIZE) { + pr_err("VFS (%s): error: unsupported blocksize for dax\n", + sb->s_id); + return -EINVAL; + } + + err = bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff); + if (err) { + pr_err("VFS (%s): error: unaligned partition for dax\n", + sb->s_id); + return err; + } + + dax_dev = dax_get_by_host(bdev->bd_disk->disk_name); + if (!dax_dev) { + pr_err("VFS (%s): error: device does not support dax\n", + sb->s_id); + return -EOPNOTSUPP; + } + + id = dax_read_lock(); + len = dax_direct_access(dax_dev, pgoff, 1, &kaddr, &pfn); + dax_read_unlock(id); + + put_dax(dax_dev); + + if (len < 1) { + pr_err("VFS (%s): error: dax access failed (%ld)", + sb->s_id, len); + return len < 0 ? len : -EIO; + } + + return 0; +} +EXPORT_SYMBOL_GPL(__bdev_dax_supported); + /** * struct dax_device - anchor object for dax services * @inode: core vfs diff --git a/fs/Kconfig b/fs/Kconfig index 83eab52fb3f6..b0e42b6a96b9 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -39,6 +39,7 @@ config FS_DAX depends on MMU depends on !(ARM || MIPS || SPARC) select FS_IOMAP + select DAX help Direct Access (DAX) can be used on memory-backed block devices. If the block device supports DAX and the filesystem supports DAX, diff --git a/fs/block_dev.c b/fs/block_dev.c index 666367e13711..3096ecd48304 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -718,72 +718,6 @@ int bdev_write_page(struct block_device *bdev, sector_t sector, } EXPORT_SYMBOL_GPL(bdev_write_page); -int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size, - pgoff_t *pgoff) -{ - phys_addr_t phys_off = (get_start_sect(bdev) + sector) * 512; - - if (pgoff) - *pgoff = PHYS_PFN(phys_off); - if (phys_off % PAGE_SIZE || size % PAGE_SIZE) - return -EINVAL; - return 0; -} -EXPORT_SYMBOL(bdev_dax_pgoff); - -/** - * bdev_dax_supported() - Check if the device supports dax for filesystem - * @sb: The superblock of the device - * @blocksize: The block size of the device - * - * This is a library function for filesystems to check if the block device - * can be mounted with dax option. - * - * Return: negative errno if unsupported, 0 if supported. - */ -int bdev_dax_supported(struct super_block *sb, int blocksize) -{ - struct block_device *bdev = sb->s_bdev; - struct dax_device *dax_dev; - pgoff_t pgoff; - int err, id; - void *kaddr; - pfn_t pfn; - long len; - - if (blocksize != PAGE_SIZE) { - vfs_msg(sb, KERN_ERR, "error: unsupported blocksize for dax"); - return -EINVAL; - } - - err = bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff); - if (err) { - vfs_msg(sb, KERN_ERR, "error: unaligned partition for dax"); - return err; - } - - dax_dev = dax_get_by_host(bdev->bd_disk->disk_name); - if (!dax_dev) { - vfs_msg(sb, KERN_ERR, "error: device does not support dax"); - return -EOPNOTSUPP; - } - - id = dax_read_lock(); - len = dax_direct_access(dax_dev, pgoff, 1, &kaddr, &pfn); - dax_read_unlock(id); - - put_dax(dax_dev); - - if (len < 1) { - vfs_msg(sb, KERN_ERR, - "error: dax access failed (%ld)", len); - return len < 0 ? len : -EIO; - } - - return 0; -} -EXPORT_SYMBOL_GPL(bdev_dax_supported); - /* * pseudo-fs */ diff --git a/fs/ext2/super.c b/fs/ext2/super.c index 9e25a71fe1a2..d07773b81da9 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -32,6 +32,7 @@ #include <linux/log2.h> #include <linux/quotaops.h> #include <linux/uaccess.h> +#include <linux/dax.h> #include "ext2.h" #include "xattr.h" #include "acl.h" diff --git a/fs/ext4/super.c b/fs/ext4/super.c index a9448db1cf7e..bf6bb8997124 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -37,6 +37,7 @@ #include <linux/ctype.h> #include <linux/log2.h> #include <linux/crc16.h> +#include <linux/dax.h> #include <linux/cleancache.h> #include <linux/uaccess.h> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 685c042a120f..f5c58d6dcafb 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -52,6 +52,7 @@ #include "xfs_reflink.h" #include <linux/namei.h> +#include <linux/dax.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/mount.h> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 848f87eb1905..e4d9899755a7 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1940,8 +1940,6 @@ extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, extern int bdev_read_page(struct block_device *, sector_t, struct page *); extern int bdev_write_page(struct block_device *, sector_t, struct page *, struct writeback_control *); -extern int bdev_dax_supported(struct super_block *, int); -int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff); #else /* CONFIG_BLOCK */ struct block_device; diff --git a/include/linux/dax.h b/include/linux/dax.h index d3158e74a59e..7fdf1d710042 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -18,12 +18,38 @@ struct dax_operations { void **, pfn_t *); }; +int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff); +#if IS_ENABLED(CONFIG_FS_DAX) +int __bdev_dax_supported(struct super_block *sb, int blocksize); +static inline int bdev_dax_supported(struct super_block *sb, int blocksize) +{ + return __bdev_dax_supported(sb, blocksize); +} +#else +static inline int bdev_dax_supported(struct super_block *sb, int blocksize) +{ + return -EOPNOTSUPP; +} +#endif + +#if IS_ENABLED(CONFIG_DAX) +struct dax_device *dax_get_by_host(const char *host); +void put_dax(struct dax_device *dax_dev); +#else +static inline struct dax_device *dax_get_by_host(const char *host) +{ + return NULL; +} + +static inline void put_dax(struct dax_device *dax_dev) +{ +} +#endif + int dax_read_lock(void); void dax_read_unlock(int id); -struct dax_device *dax_get_by_host(const char *host); struct dax_device *alloc_dax(void *private, const char *host, const struct dax_operations *ops); -void put_dax(struct dax_device *dax_dev); bool dax_alive(struct dax_device *dax_dev); void kill_dax(struct dax_device *dax_dev); void *dax_get_private(struct dax_device *dax_dev);
For configurations that do not enable DAX filesystems or drivers, do not require the DAX core to be built. Given that the 'direct_access' method has been removed from 'block_device_operations', we can also go ahead and remove the block-related dax helper functions from fs/block_dev.c to drivers/dax/super.c. This keeps dax details out of the block layer and lets the DAX core be built as a module in the FS_DAX=n case. Filesystems need to include dax.h to call bdev_dax_supported(). Cc: Jan Kara <jack@suse.com> Cc: linux-xfs@vger.kernel.org Cc: Jens Axboe <axboe@kernel.dk> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> --- Changes in v2: * kill off the remainder of the dax specific routines in the block layer and move it to the drivers/dax core. block/Kconfig | 1 - drivers/dax/super.c | 70 ++++++++++++++++++++++++++++++++++++++++++++++++ fs/Kconfig | 1 + fs/block_dev.c | 66 --------------------------------------------- fs/ext2/super.c | 1 + fs/ext4/super.c | 1 + fs/xfs/xfs_super.c | 1 + include/linux/blkdev.h | 2 - include/linux/dax.h | 30 +++++++++++++++++++-- 9 files changed, 102 insertions(+), 71 deletions(-)