From: Hongzhen Luo <[email protected]> When creating the EROFS image, users can specify the fingerprint name. This is to prepare for the upcoming inode page cache share.
Signed-off-by: Hongzhen Luo <[email protected]> Signed-off-by: Hongbo Li <[email protected]> Reviewed-by: Gao Xiang <[email protected]> --- fs/erofs/Kconfig | 9 +++++++++ fs/erofs/erofs_fs.h | 5 +++-- fs/erofs/internal.h | 2 ++ fs/erofs/super.c | 9 +++++++++ fs/erofs/xattr.c | 13 +++++++++++++ 5 files changed, 36 insertions(+), 2 deletions(-) diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig index d81f3318417d..b71f2a8074fe 100644 --- a/fs/erofs/Kconfig +++ b/fs/erofs/Kconfig @@ -194,3 +194,12 @@ config EROFS_FS_PCPU_KTHREAD_HIPRI at higher priority. If unsure, say N. + +config EROFS_FS_PAGE_CACHE_SHARE + bool "EROFS page cache share support (experimental)" + depends on EROFS_FS && EROFS_FS_XATTR && !EROFS_FS_ONDEMAND + help + This enables page cache sharing among inodes with identical + content fingerprints on the same machine. + + If unsure, say N. diff --git a/fs/erofs/erofs_fs.h b/fs/erofs/erofs_fs.h index e24268acdd62..b30a74d307c5 100644 --- a/fs/erofs/erofs_fs.h +++ b/fs/erofs/erofs_fs.h @@ -17,7 +17,7 @@ #define EROFS_FEATURE_COMPAT_XATTR_FILTER 0x00000004 #define EROFS_FEATURE_COMPAT_SHARED_EA_IN_METABOX 0x00000008 #define EROFS_FEATURE_COMPAT_PLAIN_XATTR_PFX 0x00000010 - +#define EROFS_FEATURE_COMPAT_ISHARE_XATTRS 0x00000020 /* * Any bits that aren't in EROFS_ALL_FEATURE_INCOMPAT should @@ -83,7 +83,8 @@ struct erofs_super_block { __le32 xattr_prefix_start; /* start of long xattr prefixes */ __le64 packed_nid; /* nid of the special packed inode */ __u8 xattr_filter_reserved; /* reserved for xattr name filter */ - __u8 reserved[3]; + __u8 ishare_xattr_prefix_id; + __u8 reserved[2]; __le32 build_time; /* seconds added to epoch for mkfs time */ __le64 rootnid_8b; /* (48BIT on) nid of root directory */ __le64 reserved2; diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index 98fe652aea33..ec79e8b44d3b 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -134,6 +134,7 @@ struct erofs_sb_info { u32 xattr_blkaddr; u32 xattr_prefix_start; u8 xattr_prefix_count; + u8 ishare_xattr_prefix_id; struct erofs_xattr_prefix_item *xattr_prefixes; unsigned int xattr_filter_reserved; #endif @@ -238,6 +239,7 @@ EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM) EROFS_FEATURE_FUNCS(xattr_filter, compat, COMPAT_XATTR_FILTER) EROFS_FEATURE_FUNCS(shared_ea_in_metabox, compat, COMPAT_SHARED_EA_IN_METABOX) EROFS_FEATURE_FUNCS(plain_xattr_pfx, compat, COMPAT_PLAIN_XATTR_PFX) +EROFS_FEATURE_FUNCS(ishare_xattrs, compat, COMPAT_ISHARE_XATTRS) static inline u64 erofs_nid_to_ino64(struct erofs_sb_info *sbi, erofs_nid_t nid) { diff --git a/fs/erofs/super.c b/fs/erofs/super.c index f18f43b78fca..dca1445f6c92 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -320,6 +320,15 @@ static int erofs_read_superblock(struct super_block *sb) sbi->xattr_prefix_start = le32_to_cpu(dsb->xattr_prefix_start); sbi->xattr_prefix_count = dsb->xattr_prefix_count; sbi->xattr_filter_reserved = dsb->xattr_filter_reserved; + if (erofs_sb_has_ishare_xattrs(sbi)) { + if (dsb->ishare_xattr_prefix_id >= sbi->xattr_prefix_count) { + erofs_err(sb, "invalid ishare xattr prefix id %u", + dsb->ishare_xattr_prefix_id); + ret = -EFSCORRUPTED; + goto out; + } + sbi->ishare_xattr_prefix_id = dsb->ishare_xattr_prefix_id; + } #endif sbi->islotbits = ilog2(sizeof(struct erofs_inode_compact)); if (erofs_sb_has_48bit(sbi) && dsb->rootnid_8b) { diff --git a/fs/erofs/xattr.c b/fs/erofs/xattr.c index 396536d9a862..ae61f20cb861 100644 --- a/fs/erofs/xattr.c +++ b/fs/erofs/xattr.c @@ -519,6 +519,19 @@ int erofs_xattr_prefixes_init(struct super_block *sb) } erofs_put_metabuf(&buf); + if (!ret && erofs_sb_has_ishare_xattrs(sbi)) { + struct erofs_xattr_prefix_item *pf = pfs + sbi->ishare_xattr_prefix_id; + struct erofs_xattr_long_prefix *newpfx; + + newpfx = krealloc(pf->prefix, + sizeof(*newpfx) + pf->infix_len + 1, GFP_KERNEL); + if (newpfx) { + newpfx->infix[pf->infix_len] = '\0'; + pf->prefix = newpfx; + } else { + ret = -ENOMEM; + } + } sbi->xattr_prefixes = pfs; if (ret) erofs_xattr_prefixes_cleanup(sb); -- 2.22.0
