The ->iomap_begin() operation is a hot path, so cache the
fs_dax_get_by_host() result at mount time to avoid the incurring the
hash lookup overhead on a per-i/o basis.
Cc: "Darrick J. Wong" <darrick.wong@xxxxxxxxxx>
Reported-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/dax/super.c | 10 ++++++++++
fs/super.c | 26 +++++++++++++++++++++++---
fs/xfs/xfs_aops.c | 13 +++++++++++++
fs/xfs/xfs_aops.h | 1 +
fs/xfs/xfs_buf.c | 4 +++-
fs/xfs/xfs_buf.h | 3 ++-
fs/xfs/xfs_iomap.c | 10 +---------
fs/xfs/xfs_super.c | 21 +++++++++++++++++----
include/linux/dax.h | 6 ++++++
include/linux/fs.h | 1 +
10 files changed, 77 insertions(+), 18 deletions(-)
diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 938eb4868f7f..b699aac268a6 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -46,6 +46,8 @@ void dax_read_unlock(int id)
EXPORT_SYMBOL_GPL(dax_read_unlock);
#ifdef CONFIG_BLOCK
+#include <linux/blkdev.h>
+
int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size,
pgoff_t *pgoff)
{
@@ -59,6 +61,14 @@ int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size,
}
EXPORT_SYMBOL(bdev_dax_pgoff);
+struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev)
+{
+ if (!blk_queue_dax(bdev->bd_queue))
+ return NULL;
+ return fs_dax_get_by_host(bdev->bd_disk->disk_name);
+}
+EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev);
+
/**
* __bdev_dax_supported() - Check if the device supports dax for filesystem
* @sb: The superblock of the device
diff --git a/fs/super.c b/fs/super.c
index 6bc3352adcf3..671889b02bed 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -23,6 +23,7 @@
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
+#include <linux/dax.h>
#include <linux/mount.h>
#include <linux/security.h>
#include <linux/writeback.h> /* for the emergency remount stuff */
@@ -1048,9 +1049,17 @@ struct dentry *mount_ns(struct file_system_type *fs_type,
EXPORT_SYMBOL(mount_ns);
#ifdef CONFIG_BLOCK
+struct sget_devs {
+ struct block_device *bdev;
+ struct dax_device *dax_dev;
+};
+
static int set_bdev_super(struct super_block *s, void *data)
{
- s->s_bdev = data;
+ struct sget_devs *devs = data;
+
+ s->s_bdev = devs->bdev;
+ s->s_daxdev = devs->dax_dev;
s->s_dev = s->s_bdev->bd_dev;
s->s_bdi = bdi_get(s->s_bdev->bd_bdi);
@@ -1059,14 +1068,18 @@ static int set_bdev_super(struct super_block *s, void *data)
static int test_bdev_super(struct super_block *s, void *data)
{
- return (void *)s->s_bdev == data;
+ struct sget_devs *devs = data;
+
+ return s->s_bdev == devs->bdev;
}
struct dentry *mount_bdev(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data,
int (*fill_super)(struct super_block *, void *, int))
{
+ struct sget_devs devs;
struct block_device *bdev;
+ struct dax_device *dax_dev;
struct super_block *s;
fmode_t mode = FMODE_READ | FMODE_EXCL;
int error = 0;
@@ -1077,6 +1090,7 @@ struct dentry *mount_bdev(struct file_system_type *fs_type,
bdev = blkdev_get_by_path(dev_name, mode, fs_type);
if (IS_ERR(bdev))
return ERR_CAST(bdev);
+ dax_dev = fs_dax_get_by_bdev(bdev);
/*
* once the super is inserted into the list by sget, s_umount
@@ -1089,8 +1103,10 @@ struct dentry *mount_bdev(struct file_system_type *fs_type,
error = -EBUSY;
goto error_bdev;
}
+ devs.bdev = bdev;
+ devs.dax_dev = dax_dev;
s = sget(fs_type, test_bdev_super, set_bdev_super, flags | MS_NOSEC,
- bdev);
+ &devs);
mutex_unlock(&bdev->bd_fsfreeze_mutex);
if (IS_ERR(s))
goto error_s;
@@ -1111,6 +1127,7 @@ struct dentry *mount_bdev(struct file_system_type *fs_type,
*/
up_write(&s->s_umount);
blkdev_put(bdev, mode);
+ fs_put_dax(dax_dev);
down_write(&s->s_umount);
} else {
s->s_mode = mode;
@@ -1132,6 +1149,7 @@ struct dentry *mount_bdev(struct file_system_type *fs_type,
error = PTR_ERR(s);
error_bdev:
blkdev_put(bdev, mode);
+ fs_put_dax(dax_dev);
error:
return ERR_PTR(error);
}
@@ -1140,6 +1158,7 @@ EXPORT_SYMBOL(mount_bdev);
void kill_block_super(struct super_block *sb)
{
struct block_device *bdev = sb->s_bdev;
+ struct dax_device *dax_dev = sb->s_daxdev;
fmode_t mode = sb->s_mode;
bdev->bd_super = NULL;
@@ -1147,6 +1166,7 @@ void kill_block_super(struct super_block *sb)
sync_blockdev(bdev);
WARN_ON_ONCE(!(mode & FMODE_EXCL));
blkdev_put(bdev, mode | FMODE_EXCL);
+ fs_put_dax(dax_dev);
}
EXPORT_SYMBOL(kill_block_super);
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 6bf120bb1a17..78185f3b10b2 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -80,6 +80,19 @@ xfs_find_bdev_for_inode(
return mp->m_ddev_targp->bt_bdev;
}
+struct dax_device *
+xfs_find_daxdev_for_inode(
+ struct inode *inode)
+{
+ struct xfs_inode *ip = XFS_I(inode);
+ struct xfs_mount *mp = ip->i_mount;
+
+ if (XFS_IS_REALTIME_INODE(ip))
+ return mp->m_rtdev_targp->bt_daxdev;
+ else
+ return mp->m_ddev_targp->bt_daxdev;
+}
+
/*
* We're now finished for good with this page. Update the page state via the
* associated buffer_heads, paying attention to the start and end offsets that
diff --git a/fs/xfs/xfs_aops.h b/fs/xfs/xfs_aops.h
index cc174ec6c2fd..88c85ea63da0 100644
--- a/fs/xfs/xfs_aops.h
+++ b/fs/xfs/xfs_aops.h
@@ -59,5 +59,6 @@ int xfs_setfilesize(struct xfs_inode *ip, xfs_off_t offset, size_t size);
extern void xfs_count_page_state(struct page *, int *, int *);
extern struct block_device *xfs_find_bdev_for_inode(struct inode *);
+extern struct dax_device *xfs_find_daxdev_for_inode(struct inode *);
#endif /* __XFS_AOPS_H__ */
diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 72f038492ba8..6deb86c845d1 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -1802,7 +1802,8 @@ xfs_setsize_buftarg_early(
xfs_buftarg_t *
xfs_alloc_buftarg(
struct xfs_mount *mp,
- struct block_device *bdev)
+ struct block_device *bdev,
+ struct dax_device *dax_dev)
{
xfs_buftarg_t *btp;
@@ -1811,6 +1812,7 @@ xfs_alloc_buftarg(
btp->bt_mount = mp;
btp->bt_dev = bdev->bd_dev;
btp->bt_bdev = bdev;
+ btp->bt_daxdev = dax_dev;
if (xfs_setsize_buftarg_early(btp, bdev))
goto error;
diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h
index 20721261dae5..bf71507ddb16 100644
--- a/fs/xfs/xfs_buf.h
+++ b/fs/xfs/xfs_buf.h
@@ -108,6 +108,7 @@ typedef unsigned int xfs_buf_flags_t;
typedef struct xfs_buftarg {
dev_t bt_dev;
struct block_device *bt_bdev;
+ struct dax_device *bt_daxdev;
struct xfs_mount *bt_mount;
unsigned int bt_meta_sectorsize;
size_t bt_meta_sectormask;
@@ -385,7 +386,7 @@ xfs_buf_update_cksum(struct xfs_buf *bp, unsigned long cksum_offset)
* Handling of buftargs.
*/
extern xfs_buftarg_t *xfs_alloc_buftarg(struct xfs_mount *,
- struct block_device *);
+ struct block_device *, struct dax_device *);
extern void xfs_free_buftarg(struct xfs_mount *, struct xfs_buftarg *);
extern void xfs_wait_buftarg(xfs_buftarg_t *);
extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int);
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index 813394c62849..7c934e407332 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -69,6 +69,7 @@ xfs_bmbt_to_iomap(
iomap->offset = XFS_FSB_TO_B(mp, imap->br_startoff);
iomap->length = XFS_FSB_TO_B(mp, imap->br_blockcount);
iomap->bdev = xfs_find_bdev_for_inode(VFS_I(ip));
+ iomap->dax_dev = xfs_find_daxdev_for_inode(VFS_I(ip));
}
xfs_extlen_t
@@ -976,7 +977,6 @@ xfs_file_iomap_begin(
int nimaps = 1, error = 0;
bool shared = false, trimmed = false;
unsigned lockmode;
- struct block_device *bdev;
if (XFS_FORCED_SHUTDOWN(mp))
return -EIO;
@@ -1087,13 +1087,6 @@ xfs_file_iomap_begin(
xfs_bmbt_to_iomap(ip, iomap, &imap);
- /* optionally associate a dax device with the iomap bdev */
- bdev = iomap->bdev;
- if (blk_queue_dax(bdev->bd_queue))
- iomap->dax_dev = fs_dax_get_by_host(bdev->bd_disk->disk_name);
- else
- iomap->dax_dev = NULL;
-
if (shared)
iomap->flags |= IOMAP_F_SHARED;
return 0;
@@ -1171,7 +1164,6 @@ xfs_file_iomap_end(
unsigned flags,
struct iomap *iomap)
{
- fs_put_dax(iomap->dax_dev);
if ((flags & IOMAP_WRITE) && iomap->type == IOMAP_DELALLOC)
return xfs_file_iomap_end_delalloc(XFS_I(inode), offset,
length, written, iomap);
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 38aaacdbb8b3..d863f96b16e2 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -716,13 +716,19 @@ xfs_close_devices(
{
if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
struct block_device *logdev = mp->m_logdev_targp->bt_bdev;
+ struct dax_device *dax_logdev = mp->m_logdev_targp->bt_daxdev;
+
xfs_free_buftarg(mp, mp->m_logdev_targp);
xfs_blkdev_put(logdev);
+ fs_put_dax(dax_logdev);
}
if (mp->m_rtdev_targp) {
struct block_device *rtdev = mp->m_rtdev_targp->bt_bdev;
+ struct dax_device *dax_rtdev = mp->m_rtdev_targp->bt_daxdev;
+
xfs_free_buftarg(mp, mp->m_rtdev_targp);
xfs_blkdev_put(rtdev);
+ fs_put_dax(dax_rtdev);
}
xfs_free_buftarg(mp, mp->m_ddev_targp);
}
@@ -742,7 +748,9 @@ xfs_open_devices(
struct xfs_mount *mp)
{
struct block_device *ddev = mp->m_super->s_bdev;
+ struct dax_device *dax_ddev = mp->m_super->s_daxdev;
struct block_device *logdev = NULL, *rtdev = NULL;
+ struct dax_device *dax_logdev = NULL, *dax_rtdev = NULL;
int error;
/*
@@ -752,6 +760,7 @@ xfs_open_devices(
error = xfs_blkdev_get(mp, mp->m_logname, &logdev);
if (error)
goto out;
+ dax_logdev = fs_dax_get_by_bdev(logdev);
}
if (mp->m_rtname) {
@@ -765,24 +774,25 @@ xfs_open_devices(
error = -EINVAL;
goto out_close_rtdev;
}
+ dax_rtdev = fs_dax_get_by_bdev(rtdev);
}
/*
* Setup xfs_mount buffer target pointers
*/
error = -ENOMEM;
- mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev);
+ mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev, dax_ddev);
if (!mp->m_ddev_targp)
goto out_close_rtdev;
if (rtdev) {
- mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev);
+ mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev, dax_rtdev);
if (!mp->m_rtdev_targp)
goto out_free_ddev_targ;
}
if (logdev && logdev != ddev) {
- mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev);
+ mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev, dax_logdev);
if (!mp->m_logdev_targp)
goto out_free_rtdev_targ;
} else {
@@ -798,9 +808,12 @@ xfs_open_devices(
xfs_free_buftarg(mp, mp->m_ddev_targp);
out_close_rtdev:
xfs_blkdev_put(rtdev);
+ fs_put_dax(dax_rtdev);
out_close_logdev:
- if (logdev && logdev != ddev)
+ if (logdev && logdev != ddev) {
xfs_blkdev_put(logdev);
+ fs_put_dax(dax_logdev);
+ }
out:
return error;
}
diff --git a/include/linux/dax.h b/include/linux/dax.h
index df97b7af7e2c..6e32be3badec 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -57,6 +57,7 @@ static inline void fs_put_dax(struct dax_device *dax_dev)
put_dax(dax_dev);
}
+struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev);
#else
static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
{
@@ -71,6 +72,11 @@ static inline struct dax_device *fs_dax_get_by_host(const char *host)
static inline void fs_put_dax(struct dax_device *dax_dev)
{
}
+
+struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev)
+{
+ return NULL;
+}
#endif
int dax_read_lock(void);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 6e1fd5d21248..d0e3234a1fae 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1334,6 +1334,7 @@ struct super_block {
struct hlist_bl_head s_anon; /* anonymous dentries for (nfs) exporting */
struct list_head s_mounts; /* list of mounts; _not_ for fs use */
struct block_device *s_bdev;
+ struct dax_device *s_daxdev;
struct backing_dev_info *s_bdi;
struct mtd_info *s_mtd;
struct hlist_node s_instances;
