Hi Wanpeng, > -----Original Message----- > From: Wanpeng Li [mailto:wanpeng.li@xxxxxxxxxxxxxxx] > Sent: Thursday, March 12, 2015 5:12 PM > To: Jaegeuk Kim > Cc: Changman Lee; Chao Yu; linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx; > linux-fsdevel@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Wanpeng Li > Subject: [PATCH v2] f2fs: add fast symlink support > > This patch introduces the improvement fast symlinks to allow storage of > the target path within inode, thus symlinks with short target paths are > more accessed quickly. It will fall back to using the original slow > symlink if the target path exceeds the available inode space. > > Signed-off-by: Wanpeng Li <wanpeng.li@xxxxxxxxxxxxxxx> > --- > v1 -> v2: > * set max size of fast symlink according to inline_xattr flag > > fs/f2fs/f2fs.h | 20 +++++++++++++++++++ > fs/f2fs/file.c | 2 ++ > fs/f2fs/inode.c | 9 +++++++-- > fs/f2fs/namei.c | 53 +++++++++++++++++++++++++++++++++++++++++++++---- > include/linux/f2fs_fs.h | 1 + > 5 files changed, 79 insertions(+), 6 deletions(-) > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index 511d6cd..9cc4287 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -1226,6 +1226,7 @@ enum { > FI_VOLATILE_FILE, /* indicate volatile file */ > FI_DROP_CACHE, /* drop dirty page cache */ > FI_DATA_EXIST, /* indicate data exists */ > + FI_FAST_SYMLINK, /* indicate fast symlink */ > }; > > static inline void set_inode_flag(struct f2fs_inode_info *fi, int flag) > @@ -1262,6 +1263,8 @@ static inline void get_inline_info(struct f2fs_inode_info *fi, > set_inode_flag(fi, FI_INLINE_DENTRY); > if (ri->i_inline & F2FS_DATA_EXIST) > set_inode_flag(fi, FI_DATA_EXIST); > + if (ri->i_inline & F2FS_FAST_SYMLINK) > + set_inode_flag(fi, FI_FAST_SYMLINK); > } > > static inline void set_raw_inline(struct f2fs_inode_info *fi, > @@ -1277,6 +1280,8 @@ static inline void set_raw_inline(struct f2fs_inode_info *fi, > ri->i_inline |= F2FS_INLINE_DENTRY; > if (is_inode_flag_set(fi, FI_DATA_EXIST)) > ri->i_inline |= F2FS_DATA_EXIST; > + if (is_inode_flag_set(fi, FI_FAST_SYMLINK)) > + ri->i_inline |= F2FS_FAST_SYMLINK; > } > > static inline int f2fs_has_inline_xattr(struct inode *inode) > @@ -1370,6 +1375,15 @@ static inline void f2fs_stop_checkpoint(struct f2fs_sb_info *sbi) > sbi->sb->s_flags |= MS_RDONLY; > } > > +/* > + * Test whether an inode is a fast symlink. > + */ > +static inline int f2fs_inode_is_fast_symlink(struct inode *inode) > +{ > + return (S_ISLNK(inode->i_mode) && > + is_inode_flag_set(F2FS_I(inode), FI_FAST_SYMLINK)); > +} > + > #define get_inode_mode(i) \ > ((is_inode_flag_set(F2FS_I(i), FI_ACL_MODE)) ? \ > (F2FS_I(i)->i_acl_mode) : ((i)->i_mode)) > @@ -1411,6 +1425,11 @@ void handle_failed_inode(struct inode *); > */ > struct dentry *f2fs_get_parent(struct dentry *child); > > +static inline unsigned int max_fast_symlink_size(struct inode *inode) > +{ > + return sizeof(__le32) * addrs_per_inode(F2FS_I(inode)); > +} > + > /* > * dir.c > */ > @@ -1746,6 +1765,7 @@ extern const struct address_space_operations f2fs_node_aops; > extern const struct address_space_operations f2fs_meta_aops; > extern const struct inode_operations f2fs_dir_inode_operations; > extern const struct inode_operations f2fs_symlink_inode_operations; > +extern const struct inode_operations f2fs_fast_symlink_inode_operations; > extern const struct inode_operations f2fs_special_inode_operations; > extern struct kmem_cache *inode_entry_slab; > > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > index f1341c7..05a3d4f 100644 > --- a/fs/f2fs/file.c > +++ b/fs/f2fs/file.c > @@ -546,6 +546,8 @@ void f2fs_truncate(struct inode *inode) > if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || > S_ISLNK(inode->i_mode))) > return; > + if (f2fs_inode_is_fast_symlink(inode)) We should handle fast symlink in remove_inode_page to avoid invoking truncate_data_blocks_range incorrectly. Thanks, > + return; > > trace_f2fs_truncate(inode); > > diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c > index b508744..ec9ad22 100644 > --- a/fs/f2fs/inode.c > +++ b/fs/f2fs/inode.c > @@ -13,6 +13,7 @@ > #include <linux/buffer_head.h> > #include <linux/writeback.h> > #include <linux/bitops.h> > +#include <linux/namei.h> > > #include "f2fs.h" > #include "node.h" > @@ -188,8 +189,12 @@ make_now: > inode->i_mapping->a_ops = &f2fs_dblock_aops; > mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_HIGH_ZERO); > } else if (S_ISLNK(inode->i_mode)) { > - inode->i_op = &f2fs_symlink_inode_operations; > - inode->i_mapping->a_ops = &f2fs_dblock_aops; > + if (f2fs_inode_is_fast_symlink(inode)) > + inode->i_op = &f2fs_fast_symlink_inode_operations; > + else { > + inode->i_op = &f2fs_symlink_inode_operations; > + inode->i_mapping->a_ops = &f2fs_dblock_aops; > + } > } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || > S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { > inode->i_op = &f2fs_special_inode_operations; > diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c > index 1e2ae21..ab75ad6 100644 > --- a/fs/f2fs/namei.c > +++ b/fs/f2fs/namei.c > @@ -14,6 +14,7 @@ > #include <linux/sched.h> > #include <linux/ctype.h> > #include <linux/dcache.h> > +#include <linux/namei.h> > > #include "f2fs.h" > #include "node.h" > @@ -247,6 +248,21 @@ fail: > return err; > } > > +static void *f2fs_follow_link(struct dentry *dentry, struct nameidata *nd) > +{ > + struct page *node_page; > + > + node_page = get_node_page(F2FS_I_SB(dentry->d_inode), > + dentry->d_inode->i_ino); > + if (IS_ERR(node_page)) { > + nd_set_link(nd, NULL); > + return NULL; > + } > + nd_set_link(nd, (char *)(F2FS_INODE(node_page)->i_addr)); > + f2fs_put_page(node_page, 1); > + return NULL; > +} > + > static int f2fs_symlink(struct inode *dir, struct dentry *dentry, > const char *symname) > { > @@ -261,16 +277,31 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry, > if (IS_ERR(inode)) > return PTR_ERR(inode); > > - inode->i_op = &f2fs_symlink_inode_operations; > - inode->i_mapping->a_ops = &f2fs_dblock_aops; > - > f2fs_lock_op(sbi); > err = f2fs_add_link(dentry, inode); > if (err) > goto out; > f2fs_unlock_op(sbi); > > - err = page_symlink(inode, symname, symlen); > + > + if (symlen > max_fast_symlink_size(inode)) { > + /* slow symlink */ > + inode->i_op = &f2fs_symlink_inode_operations; > + inode->i_mapping->a_ops = &f2fs_dblock_aops; > + err = page_symlink(inode, symname, symlen); > + } else { > + /* fast symlink */ > + struct page *node_page; > + > + inode->i_op = &f2fs_fast_symlink_inode_operations; > + node_page = get_node_page(sbi, inode->i_ino); > + memcpy((char *)&F2FS_INODE(node_page)->i_addr, symname, symlen); > + set_page_dirty(node_page); > + f2fs_put_page(node_page, 1); > + inode->i_size = symlen-1; > + set_inode_flag(F2FS_I(inode), FI_FAST_SYMLINK); > + mark_inode_dirty(inode); > + } > alloc_nid_done(sbi, inode->i_ino); > > d_instantiate(dentry, inode); > @@ -743,6 +774,20 @@ const struct inode_operations f2fs_symlink_inode_operations = { > #endif > }; > > +const struct inode_operations f2fs_fast_symlink_inode_operations = { > + .readlink = generic_readlink, > + .follow_link = f2fs_follow_link, > + .put_link = page_put_link, > + .getattr = f2fs_getattr, > + .setattr = f2fs_setattr, > +#ifdef CONFIG_F2FS_FS_XATTR > + .setxattr = generic_setxattr, > + .getxattr = generic_getxattr, > + .listxattr = f2fs_listxattr, > + .removexattr = generic_removexattr, > +#endif > +}; > + > const struct inode_operations f2fs_special_inode_operations = { > .getattr = f2fs_getattr, > .setattr = f2fs_setattr, > diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h > index 502f28c..a317234 100644 > --- a/include/linux/f2fs_fs.h > +++ b/include/linux/f2fs_fs.h > @@ -178,6 +178,7 @@ struct f2fs_extent { > #define F2FS_INLINE_DATA 0x02 /* file inline data flag */ > #define F2FS_INLINE_DENTRY 0x04 /* file inline dentry flag */ > #define F2FS_DATA_EXIST 0x08 /* file inline data exist flag */ > +#define F2FS_FAST_SYMLINK 0x10 /* file fast symlink flag */ > > #define MAX_INLINE_DATA (sizeof(__le32) * (DEF_ADDRS_PER_INODE - \ > F2FS_INLINE_XATTR_ADDRS - 1)) > -- > 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
