Implementation btrfs .metadata_readahead. In btrfs, all metadata pages are in a
special btree_inode. We do readahead in it.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
---
fs/btrfs/disk-io.c | 10 ++++++++++
fs/btrfs/super.c | 13 +++++++++++++
mm/readahead.c | 1 +
3 files changed, 24 insertions(+)
Index: linux/fs/btrfs/disk-io.c
==================================================================---
linux.orig/fs/btrfs/disk-io.c 2010-12-07 13:32:24.000000000 +0800
+++ linux/fs/btrfs/disk-io.c 2010-12-07 13:33:08.000000000 +0800
@@ -776,6 +776,15 @@ static int btree_readpage(struct file *f
return extent_read_full_page(tree, page, btree_get_extent);
}
+static int btree_readpages(struct file *file, struct address_space *mapping,
+ struct list_head *pages, unsigned nr_pages)
+{
+ struct extent_io_tree *tree;
+ tree = &BTRFS_I(mapping->host)->io_tree;
+ return extent_readpages(tree, mapping, pages, nr_pages,
+ btree_get_extent);
+}
+
static int btree_releasepage(struct page *page, gfp_t gfp_flags)
{
struct extent_io_tree *tree;
@@ -819,6 +828,7 @@ static void btree_invalidatepage(struct
static const struct address_space_operations btree_aops = {
.readpage = btree_readpage,
+ .readpages = btree_readpages,
.writepage = btree_writepage,
.writepages = btree_writepages,
.releasepage = btree_releasepage,
Index: linux/fs/btrfs/super.c
==================================================================---
linux.orig/fs/btrfs/super.c 2010-12-07 13:32:24.000000000 +0800
+++ linux/fs/btrfs/super.c 2010-12-07 13:33:08.000000000 +0800
@@ -892,6 +892,18 @@ out:
return -ENOENT;
}
+static int btrfs_metadata_readahead(struct super_block *sb, loff_t offset,
+ ssize_t size)
+{
+ struct btrfs_root *tree_root = btrfs_sb(sb);
+ struct inode *btree_inode = tree_root->fs_info->btree_inode;
+ struct address_space *mapping = btree_inode->i_mapping;
+
+ force_page_cache_readahead(mapping, NULL, offset >> PAGE_CACHE_SHIFT,
+ size >> PAGE_CACHE_SHIFT);
+ return 0;
+}
+
static const struct super_operations btrfs_super_ops = {
.drop_inode = btrfs_drop_inode,
.evict_inode = btrfs_evict_inode,
@@ -907,6 +919,7 @@ static const struct super_operations btr
.freeze_fs = btrfs_freeze,
.unfreeze_fs = btrfs_unfreeze,
.metadata_incore = btrfs_metadata_incore,
+ .metadata_readahead = btrfs_metadata_readahead,
};
static const struct file_operations btrfs_ctl_fops = {
Index: linux/mm/readahead.c
==================================================================---
linux.orig/mm/readahead.c 2010-12-07 13:32:24.000000000 +0800
+++ linux/mm/readahead.c 2010-12-07 13:33:08.000000000 +0800
@@ -228,6 +228,7 @@ int force_page_cache_readahead(struct ad
}
return ret;
}
+EXPORT_SYMBOL_GPL(force_page_cache_readahead);
/*
* Given a desired number of PAGE_CACHE_SIZE readahead pages, return a
--
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On Mon, Dec 13, 2010 at 3:22 PM, Shaohua Li <shaohua.li@intel.com> wrote:> Implementation btrfs .metadata_readahead. In btrfs, all metadata pages are in a > special btree_inode. We do readahead in it. > > Signed-off-by: Shaohua Li <shaohua.li@intel.com> > > --- > fs/btrfs/disk-io.c | 10 ++++++++++ > fs/btrfs/super.c | 13 +++++++++++++ > mm/readahead.c | 1 + > 3 files changed, 24 insertions(+) > > Index: linux/fs/btrfs/disk-io.c > ==================================================================> --- linux.orig/fs/btrfs/disk-io.c 2010-12-07 13:32:24.000000000 +0800 > +++ linux/fs/btrfs/disk-io.c 2010-12-07 13:33:08.000000000 +0800 > @@ -776,6 +776,15 @@ static int btree_readpage(struct file *f > return extent_read_full_page(tree, page, btree_get_extent); > } > > +static int btree_readpages(struct file *file, struct address_space *mapping, > + struct list_head *pages, unsigned nr_pages) > +{ > + struct extent_io_tree *tree; > + tree = &BTRFS_I(mapping->host)->io_tree; > + return extent_readpages(tree, mapping, pages, nr_pages, > + btree_get_extent); > +} > + > static int btree_releasepage(struct page *page, gfp_t gfp_flags) > { > struct extent_io_tree *tree; > @@ -819,6 +828,7 @@ static void btree_invalidatepage(struct > > static const struct address_space_operations btree_aops = { > .readpage = btree_readpage, > + .readpages = btree_readpages, > .writepage = btree_writepage, > .writepages = btree_writepages, > .releasepage = btree_releasepage, > Index: linux/fs/btrfs/super.c > ==================================================================> --- linux.orig/fs/btrfs/super.c 2010-12-07 13:32:24.000000000 +0800 > +++ linux/fs/btrfs/super.c 2010-12-07 13:33:08.000000000 +0800 > @@ -892,6 +892,18 @@ out: > return -ENOENT; > } > > +static int btrfs_metadata_readahead(struct super_block *sb, loff_t offset, > + ssize_t size) > +{ > + struct btrfs_root *tree_root = btrfs_sb(sb); > + struct inode *btree_inode = tree_root->fs_info->btree_inode; > + struct address_space *mapping = btree_inode->i_mapping; > + > + force_page_cache_readahead(mapping, NULL, offset >> PAGE_CACHE_SHIFT, > + size >> PAGE_CACHE_SHIFT); > + return 0; > +} > + > static const struct super_operations btrfs_super_ops = { > .drop_inode = btrfs_drop_inode, > .evict_inode = btrfs_evict_inode, > @@ -907,6 +919,7 @@ static const struct super_operations btr > .freeze_fs = btrfs_freeze, > .unfreeze_fs = btrfs_unfreeze, > .metadata_incore = btrfs_metadata_incore, > + .metadata_readahead = btrfs_metadata_readahead, > }; > > static const struct file_operations btrfs_ctl_fops = { > Index: linux/mm/readahead.c > ==================================================================> --- linux.orig/mm/readahead.c 2010-12-07 13:32:24.000000000 +0800 > +++ linux/mm/readahead.c 2010-12-07 13:33:08.000000000 +0800 > @@ -228,6 +228,7 @@ int force_page_cache_readahead(struct ad > } > return ret; > } > +EXPORT_SYMBOL_GPL(force_page_cache_readahead); > > /* > * Given a desired number of PAGE_CACHE_SIZE readahead pages, return a > >btrfs will crash If the read-ahead range falls into unallocated chunk. need code to check validity of the user input. Yan, Zheng -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 2010-12-14 at 09:06 +0800, Yan, Zheng wrote:> On Mon, Dec 13, 2010 at 3:22 PM, Shaohua Li <shaohua.li@intel.com> wrote: > > Implementation btrfs .metadata_readahead. In btrfs, all metadata pages are in a > > special btree_inode. We do readahead in it. > > > > Signed-off-by: Shaohua Li <shaohua.li@intel.com> > > > > --- > > fs/btrfs/disk-io.c | 10 ++++++++++ > > fs/btrfs/super.c | 13 +++++++++++++ > > mm/readahead.c | 1 + > > 3 files changed, 24 insertions(+) > > > > Index: linux/fs/btrfs/disk-io.c > > ==================================================================> > --- linux.orig/fs/btrfs/disk-io.c 2010-12-07 13:32:24.000000000 +0800 > > +++ linux/fs/btrfs/disk-io.c 2010-12-07 13:33:08.000000000 +0800 > > @@ -776,6 +776,15 @@ static int btree_readpage(struct file *f > > return extent_read_full_page(tree, page, btree_get_extent); > > } > > > > +static int btree_readpages(struct file *file, struct address_space *mapping, > > + struct list_head *pages, unsigned nr_pages) > > +{ > > + struct extent_io_tree *tree; > > + tree = &BTRFS_I(mapping->host)->io_tree; > > + return extent_readpages(tree, mapping, pages, nr_pages, > > + btree_get_extent); > > +} > > + > > static int btree_releasepage(struct page *page, gfp_t gfp_flags) > > { > > struct extent_io_tree *tree; > > @@ -819,6 +828,7 @@ static void btree_invalidatepage(struct > > > > static const struct address_space_operations btree_aops = { > > .readpage = btree_readpage, > > + .readpages = btree_readpages, > > .writepage = btree_writepage, > > .writepages = btree_writepages, > > .releasepage = btree_releasepage, > > Index: linux/fs/btrfs/super.c > > ==================================================================> > --- linux.orig/fs/btrfs/super.c 2010-12-07 13:32:24.000000000 +0800 > > +++ linux/fs/btrfs/super.c 2010-12-07 13:33:08.000000000 +0800 > > @@ -892,6 +892,18 @@ out: > > return -ENOENT; > > } > > > > +static int btrfs_metadata_readahead(struct super_block *sb, loff_t offset, > > + ssize_t size) > > +{ > > + struct btrfs_root *tree_root = btrfs_sb(sb); > > + struct inode *btree_inode = tree_root->fs_info->btree_inode; > > + struct address_space *mapping = btree_inode->i_mapping; > > + > > + force_page_cache_readahead(mapping, NULL, offset >> PAGE_CACHE_SHIFT, > > + size >> PAGE_CACHE_SHIFT); > > + return 0; > > +} > > + > > static const struct super_operations btrfs_super_ops = { > > .drop_inode = btrfs_drop_inode, > > .evict_inode = btrfs_evict_inode, > > @@ -907,6 +919,7 @@ static const struct super_operations btr > > .freeze_fs = btrfs_freeze, > > .unfreeze_fs = btrfs_unfreeze, > > .metadata_incore = btrfs_metadata_incore, > > + .metadata_readahead = btrfs_metadata_readahead, > > }; > > > > static const struct file_operations btrfs_ctl_fops = { > > Index: linux/mm/readahead.c > > ==================================================================> > --- linux.orig/mm/readahead.c 2010-12-07 13:32:24.000000000 +0800 > > +++ linux/mm/readahead.c 2010-12-07 13:33:08.000000000 +0800 > > @@ -228,6 +228,7 @@ int force_page_cache_readahead(struct ad > > } > > return ret; > > } > > +EXPORT_SYMBOL_GPL(force_page_cache_readahead); > > > > /* > > * Given a desired number of PAGE_CACHE_SIZE readahead pages, return a > > > > > > btrfs will crash If the read-ahead range falls into unallocated chunk. > need code to check validity of the user input.didn''t hit this, maybe I''m lucky. I''ll double check this. Thanks, Shaohua -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html