xfs: sanitise supberlock feature bit support
cover xfs: sanitise supberlock feature bit support
Hi folks,
This patchset is a followup to the original feature bit cleanup patch I sent here:
http://oss.sgi.com/archives/xfs/2014-03/msg00101.html
It basically removes all the old cruft that we inherited from Irix (such as tests and conversion to/from v1-3 superblocks) that we've never supported on Linux. On Linux, we've ony ever supported V2 directories, and so anything that doesn't know about V2 directories is simply going to be rejected at mount time. Hence we don't need all the code to handle versions older than this.
Nor do we care about Irix bootloader feature bit masks (the SASH feature bits) or about things that were never implemented like shared readonly superblock support. Hence we can remove a fairly large chunk of complexity out of the feature bit testing if we only test for things that we can support.
Further, we should really always use to v2 inodes these days on v4 superblock filesystems. We've been setting the NLINK feature bit by default at mkfs time since 2007, so no we make the kernel set it by default at mount time, too. This means that we always convert v1 inodes to v2 inodes, and so reduce the number of different code paths we need to test and support.
Thoughts, comments?
Cheers,
Dave.
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PATCH 1/5 xfs: make superblock version checks reflect reality
From: Dave Chinner <[email protected]>
We only support filesystems that have v2 directory support, and than means all the checking and handling of superblock versions prior to this support being added is completely unnecessary overhead.
Strip out all the version 1-3 support, sanitise the good version checking to reflect the supported versions, update all the feature supported functions and clean up all the support bit definitions to reflect the fact that we no longer care about Irix bootloader flag regions for v4 feature bits. Also, convert the return values to boolean types and remove typedefs from function declarations to clean up calling conventions, too.
Because the feature bit checking is all inline code, this relatively small cleanup has a noticable impact on code size:
text data bss dec hex filename 785195 100867 616 886678 d8796 fs/xfs/xfs.o.orig 783595 100867 616 885078 d8156 fs/xfs/xfs.o.patched
i.e. it reduces it by 1600 bytes.
--- fs/xfs/xfs_sb.h | 215 ++++++++++++++++++++------------------------------------ 1 file changed, 77 insertions(+), 138 deletions(-)
fs/xfs/xfs_sb.h +77 -138
@@ -36,8 +36,6 @@ struct xfs_trans;#define XFS_SB_VERSION_5 5/* CRC enabled filesystem */ #define XFS_SB_VERSION_NUMBITS 0x000f#define XFS_SB_VERSION_ALLFBITS 0xfff0 -#define XFS_SB_VERSION_SASHFBITS 0xf000 -#define XFS_SB_VERSION_REALFBITS 0x0ff0#define XFS_SB_VERSION_ATTRBIT 0x0010#define XFS_SB_VERSION_NLINKBIT 0x0020#define XFS_SB_VERSION_QUOTABIT 0x0040
@@ -50,24 +48,14 @@ struct xfs_trans;#define XFS_SB_VERSION_DIRV2BIT 0x2000#define XFS_SB_VERSION_BORGBIT 0x4000/* ASCII only case-insens. */ #define XFS_SB_VERSION_MOREBITSBIT 0x8000 -#define XFS_SB_VERSION_OKSASHFBITS \ - (XFS_SB_VERSION_EXTFLGBIT | \ - XFS_SB_VERSION_DIRV2BIT | \ - XFS_SB_VERSION_BORGBIT) -#define XFS_SB_VERSION_OKREALFBITS \ - (XFS_SB_VERSION_ATTRBIT | \ - XFS_SB_VERSION_NLINKBIT | \ - XFS_SB_VERSION_QUOTABIT | \ - XFS_SB_VERSION_ALIGNBIT | \ - XFS_SB_VERSION_DALIGNBIT | \ - XFS_SB_VERSION_SHAREDBIT | \ - XFS_SB_VERSION_LOGV2BIT | \ - XFS_SB_VERSION_SECTORBIT | \ - XFS_SB_VERSION_MOREBITSBIT) -#define XFS_SB_VERSION_OKREALBITS \ - (XFS_SB_VERSION_NUMBITS | \ - XFS_SB_VERSION_OKREALFBITS | \ - XFS_SB_VERSION_OKSASHFBITS) + +/* +* Supported feature bit list is just all bits in the versionnum field because +* we've used them all up and understand them all. +*/ +#define XFS_SB_VERSION_OKBITS \ + (XFS_SB_VERSION_NUMBITS | \ + XFS_SB_VERSION_ALLFBITS)/* * There are two words to hold XFS "feature" bits: the original
@@ -76,7 +64,6 @@ struct xfs_trans;* * These defines represent bits in sb_features2. */ -#define XFS_SB_VERSION2_REALFBITS 0x00ffffff/* Mask: features */ #define XFS_SB_VERSION2_RESERVED1BIT 0x00000001#define XFS_SB_VERSION2_LAZYSBCOUNTBIT 0x00000002/* Superblk counters */ #define XFS_SB_VERSION2_RESERVED4BIT 0x00000004
@@ -86,16 +73,11 @@ struct xfs_trans;#define XFS_SB_VERSION2_CRCBIT 0x00000100/* metadata CRCs */ #define XFS_SB_VERSION2_FTYPE 0x00000200/* inode type in dir */ -#define XFS_SB_VERSION2_OKREALFBITS \ +#define XFS_SB_VERSION2_OKBITS \ (XFS_SB_VERSION2_LAZYSBCOUNTBIT | \ XFS_SB_VERSION2_ATTR2BIT | \ XFS_SB_VERSION2_PROJID32BIT | \ XFS_SB_VERSION2_FTYPE) -#define XFS_SB_VERSION2_OKSASHFBITS \ - (0) -#define XFS_SB_VERSION2_OKREALBITS \ - (XFS_SB_VERSION2_OKREALFBITS | \ - XFS_SB_VERSION2_OKSASHFBITS )/* * Superblock - in core version. Must match the ondisk version below.
@@ -345,167 +327,124 @@ typedef enum {#define XFS_SB_VERSION_NUM (sbp) ((sbp)->sb_versionnum & XFS_SB_VERSION_NUMBITS) -static inline int xfs_sb_good_version (xfs_sb_t *sbp) +/* +* The first XFS version we support is a v4 superblock with V2 directories. +*/ +static inline bool xfs_sb_good_v4_features (struct xfs_sb *sbp) { -/* We always support version 1-3 */ -if (sbp->sb_versionnum >=XFS_SB_VERSION_1 && - sbp->sb_versionnum <=XFS_SB_VERSION_3 ) -return 1 ; +if (!(sbp->sb_versionnum &XFS_SB_VERSION_DIRV2BIT )) +return false; -/* We support version 4 if all feature bits are supported */ -if (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_4 ) { -if ((sbp->sb_versionnum & ~XFS_SB_VERSION_OKREALBITS ) || - ((sbp->sb_versionnum &XFS_SB_VERSION_MOREBITSBIT ) && - (sbp->sb_features2 & ~XFS_SB_VERSION2_OKREALBITS ))) -return 0 ; +/* check for unknown features in the fs */ +if ((sbp->sb_versionnum & ~XFS_SB_VERSION_OKBITS ) || + ((sbp->sb_versionnum &XFS_SB_VERSION_MOREBITSBIT ) && + (sbp->sb_features2 & ~XFS_SB_VERSION2_OKBITS ))) +return false; -if (sbp->sb_shared_vn >XFS_SB_MAX_SHARED_VN ) -return 0 ; -return 1 ; - } -if (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ) -return 1 ; +/* We don't support shared superblocks - nobody knows what it is */ +if (sbp->sb_versionnum &XFS_SB_VERSION_SHAREDBIT ) +return false; -return 0 ; +return true; +} + +static inline bool xfs_sb_good_version (struct xfs_sb *sbp) +{ +if (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ) +return true; +if (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_4 ) +return xfs_sb_good_v4_features (sbp); +return false; }/* * Detect a mismatched features2 field. Older kernels read/wrote * this into the wrong slot, so to be safe we keep them in sync. */ -static inline int xfs_sb_has_mismatched_features2 (xfs_sb_t *sbp) +static inline bool xfs_sb_has_mismatched_features2 (struct xfs_sb *sbp) { -return (sbp->sb_bad_features2 != sbp->sb_features2); +return sbp->sb_bad_features2 != sbp->sb_features2; } -static inline unsigned xfs_sb_version_tonew (unsigned v) +static inline bool xfs_sb_version_hasattr (struct xfs_sb *sbp) { -if (v ==XFS_SB_VERSION_1 ) -return XFS_SB_VERSION_4 ; - -if (v ==XFS_SB_VERSION_2 ) -return XFS_SB_VERSION_4 |XFS_SB_VERSION_ATTRBIT ; - -return XFS_SB_VERSION_4 |XFS_SB_VERSION_ATTRBIT | -XFS_SB_VERSION_NLINKBIT ; +return (sbp->sb_versionnum &XFS_SB_VERSION_ATTRBIT ); } -static inline unsigned xfs_sb_version_toold (unsigned v) +static inline void xfs_sb_version_addattr (struct xfs_sb *sbp) { -if (v & (XFS_SB_VERSION_QUOTABIT |XFS_SB_VERSION_ALIGNBIT )) -return 0 ; -if (v &XFS_SB_VERSION_NLINKBIT ) -return XFS_SB_VERSION_3 ; -if (v &XFS_SB_VERSION_ATTRBIT ) -return XFS_SB_VERSION_2 ; -return XFS_SB_VERSION_1 ; + sbp->sb_versionnum |=XFS_SB_VERSION_ATTRBIT ; } -static inline int xfs_sb_version_hasattr (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hasnlink (struct xfs_sb *sbp) { -return sbp->sb_versionnum ==XFS_SB_VERSION_2 || - sbp->sb_versionnum ==XFS_SB_VERSION_3 || - (XFS_SB_VERSION_NUM (sbp) >=XFS_SB_VERSION_4 && - (sbp->sb_versionnum &XFS_SB_VERSION_ATTRBIT )); +return (sbp->sb_versionnum &XFS_SB_VERSION_NLINKBIT ); } -static inline void xfs_sb_version_addattr (xfs_sb_t *sbp) +static inline void xfs_sb_version_addnlink (struct xfs_sb *sbp) { -if (sbp->sb_versionnum ==XFS_SB_VERSION_1 ) - sbp->sb_versionnum =XFS_SB_VERSION_2 ; -else if (XFS_SB_VERSION_NUM (sbp) >=XFS_SB_VERSION_4 ) - sbp->sb_versionnum |=XFS_SB_VERSION_ATTRBIT ; -else - sbp->sb_versionnum =XFS_SB_VERSION_4 |XFS_SB_VERSION_ATTRBIT ; + sbp->sb_versionnum |=XFS_SB_VERSION_NLINKBIT ; } -static inline int xfs_sb_version_hasnlink (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hasquota (struct xfs_sb *sbp) { -return sbp->sb_versionnum ==XFS_SB_VERSION_3 || - (XFS_SB_VERSION_NUM (sbp) >=XFS_SB_VERSION_4 && - (sbp->sb_versionnum &XFS_SB_VERSION_NLINKBIT )); +return (sbp->sb_versionnum &XFS_SB_VERSION_QUOTABIT ); } -static inline void xfs_sb_version_addnlink (xfs_sb_t *sbp) +static inline void xfs_sb_version_addquota (struct xfs_sb *sbp) { -if (sbp->sb_versionnum <=XFS_SB_VERSION_2 ) - sbp->sb_versionnum =XFS_SB_VERSION_3 ; -else - sbp->sb_versionnum |=XFS_SB_VERSION_NLINKBIT ; + sbp->sb_versionnum |=XFS_SB_VERSION_QUOTABIT ; } -static inline int xfs_sb_version_hasquota (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hasalign (struct xfs_sb *sbp) { -return XFS_SB_VERSION_NUM (sbp) >=XFS_SB_VERSION_4 && - (sbp->sb_versionnum &XFS_SB_VERSION_QUOTABIT ); -} - -static inline void xfs_sb_version_addquota (xfs_sb_t *sbp) -{ -if (XFS_SB_VERSION_NUM (sbp) >=XFS_SB_VERSION_4 ) - sbp->sb_versionnum |=XFS_SB_VERSION_QUOTABIT ; -else - sbp->sb_versionnum =xfs_sb_version_tonew (sbp->sb_versionnum) | -XFS_SB_VERSION_QUOTABIT ; -} - -static inline int xfs_sb_version_hasalign (xfs_sb_t *sbp) -{ -return (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ) || - (XFS_SB_VERSION_NUM (sbp) >=XFS_SB_VERSION_4 && +return (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 || (sbp->sb_versionnum &XFS_SB_VERSION_ALIGNBIT )); } -static inline int xfs_sb_version_hasdalign (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hasdalign (struct xfs_sb *sbp) { -return XFS_SB_VERSION_NUM (sbp) >=XFS_SB_VERSION_4 && - (sbp->sb_versionnum &XFS_SB_VERSION_DALIGNBIT ); +return (sbp->sb_versionnum &XFS_SB_VERSION_DALIGNBIT ); } -static inline int xfs_sb_version_hasshared (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hasshared (struct xfs_sb *sbp) {return XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_4 && (sbp->sb_versionnum &XFS_SB_VERSION_SHAREDBIT ); } -static inline int xfs_sb_version_hasdirv2 (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hasdirv2 (struct xfs_sb *sbp) { -return (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ) || - (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_4 && - (sbp->sb_versionnum &XFS_SB_VERSION_DIRV2BIT )); +return XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 || + (sbp->sb_versionnum &XFS_SB_VERSION_DIRV2BIT ); } -static inline int xfs_sb_version_haslogv2 (xfs_sb_t *sbp) +static inline bool xfs_sb_version_haslogv2 (struct xfs_sb *sbp) { -return (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ) || - (XFS_SB_VERSION_NUM (sbp) >=XFS_SB_VERSION_4 && - (sbp->sb_versionnum &XFS_SB_VERSION_LOGV2BIT )); +return XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 || + (sbp->sb_versionnum &XFS_SB_VERSION_LOGV2BIT ); } -static inline int xfs_sb_version_hasextflgbit (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hasextflgbit (struct xfs_sb *sbp) { -return (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ) || - (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_4 && - (sbp->sb_versionnum &XFS_SB_VERSION_EXTFLGBIT )); +return XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 || + (sbp->sb_versionnum &XFS_SB_VERSION_EXTFLGBIT ); } -static inline int xfs_sb_version_hassector (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hassector (struct xfs_sb *sbp) { -return XFS_SB_VERSION_NUM (sbp) >=XFS_SB_VERSION_4 && - (sbp->sb_versionnum &XFS_SB_VERSION_SECTORBIT ); +return (sbp->sb_versionnum &XFS_SB_VERSION_SECTORBIT ); } -static inline int xfs_sb_version_hasasciici (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hasasciici (struct xfs_sb *sbp) { -return XFS_SB_VERSION_NUM (sbp) >=XFS_SB_VERSION_4 && - (sbp->sb_versionnum &XFS_SB_VERSION_BORGBIT ); +return (sbp->sb_versionnum &XFS_SB_VERSION_BORGBIT ); } -static inline int xfs_sb_version_hasmorebits (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hasmorebits (struct xfs_sb *sbp) { -return (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ) || - (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_4 && - (sbp->sb_versionnum &XFS_SB_VERSION_MOREBITSBIT )); +return XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 || + (sbp->sb_versionnum &XFS_SB_VERSION_MOREBITSBIT ); }/*
@@ -513,46 +452,46 @@ static inline int xfs_sb_version_hasmorebits(xfs_sb_t *sbp)* * For example, for a bit defined as XFS_SB_VERSION2_FUNBIT, has a macro: * -* SB_VERSION_HASFUNBIT(xfs_sb_t *sbp) +* SB_VERSION_HASFUNBIT(struct xfs_sb *sbp) * ((xfs_sb_version_hasmorebits(sbp) && * ((sbp)->sb_features2 & XFS_SB_VERSION2_FUNBIT) */ -static inline int xfs_sb_version_haslazysbcount (xfs_sb_t *sbp) +static inline bool xfs_sb_version_haslazysbcount (struct xfs_sb *sbp) {return (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ) || (xfs_sb_version_hasmorebits (sbp) && (sbp->sb_features2 &XFS_SB_VERSION2_LAZYSBCOUNTBIT )); } -static inline int xfs_sb_version_hasattr2 (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hasattr2 (struct xfs_sb *sbp) {return (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ) || (xfs_sb_version_hasmorebits (sbp) && (sbp->sb_features2 &XFS_SB_VERSION2_ATTR2BIT )); } -static inline void xfs_sb_version_addattr2 (xfs_sb_t *sbp) +static inline void xfs_sb_version_addattr2 (struct xfs_sb *sbp) { sbp->sb_versionnum |=XFS_SB_VERSION_MOREBITSBIT ; sbp->sb_features2 |=XFS_SB_VERSION2_ATTR2BIT ; } -static inline void xfs_sb_version_removeattr2 (xfs_sb_t *sbp) +static inline void xfs_sb_version_removeattr2 (struct xfs_sb *sbp) { sbp->sb_features2 &= ~XFS_SB_VERSION2_ATTR2BIT ;if (!sbp->sb_features2) sbp->sb_versionnum &= ~XFS_SB_VERSION_MOREBITSBIT ; } -static inline int xfs_sb_version_hasprojid32bit (xfs_sb_t *sbp) +static inline bool xfs_sb_version_hasprojid32bit (struct xfs_sb *sbp) {return (XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ) || (xfs_sb_version_hasmorebits (sbp) && (sbp->sb_features2 &XFS_SB_VERSION2_PROJID32BIT )); } -static inline void xfs_sb_version_addprojid32bit (xfs_sb_t *sbp) +static inline void xfs_sb_version_addprojid32bit (struct xfs_sb *sbp) { sbp->sb_versionnum |=XFS_SB_VERSION_MOREBITSBIT ; sbp->sb_features2 |=XFS_SB_VERSION2_PROJID32BIT ;
@@ -625,12 +564,12 @@ xfs_sb_has_incompat_log_feature(/* * V5 superblock specific feature checks */ -static inline int xfs_sb_version_hascrc (xfs_sb_t *sbp) +static inline int xfs_sb_version_hascrc (struct xfs_sb *sbp) {return XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ; } -static inline int xfs_sb_version_has_pquotino (xfs_sb_t *sbp) +static inline int xfs_sb_version_has_pquotino (struct xfs_sb *sbp) {return XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 ; }
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1.9.0 _______________________________________________ xfs mailing list [email protected] http://oss.sgi.com/mailman/listinfo/xfs
Re: [PATCH 1/5] xfs: make superblock version checks reflect reality
fs/xfs/xfs_sb.h typedef enum { · line 339
Quoted 10 lines
fs/xfs/xfs_sb.h +8
-0+/* +* The first XFS version we support is a v4 superblock with V2 directories. +*/ +static inline bool xfs_sb_good_v4_features (struct xfs_sb *sbp) { +if (!(sbp->sb_versionnum &XFS_SB_VERSION_DIRV2BIT )) +return false; +/* check for unknown features in the fs */ + if ((sbp->sb_versionnum & ~XFS_SB_VERSION_OKBITS) ||
Given that sb_versionnum is a __uint16_t and XFS_SB_VERSION_OKBITS is 0xffff this will never evaluate to false and a sane compiler should warn about it. How about remove this check and XFS_SB_VERSION_OKBITS?
The various has_ macros are a bit confusing to me, as some explicitly check for 5 superblocks, and some assume the caller handles them in some way, but I think this is something we can leave for later cleanups.
Quoted 8 lines
* For example, for a bit defined as
XFS_SB_VERSION2_FUNBIT, has a macro:
*
- *SB_VERSION_HASFUNBIT(xfs_sb_t *sbp)
+ *SB_VERSION_HASFUNBIT(struct xfs_sb *sbp)* ((
xfs_sb_version_hasmorebits(sbp)&&
* ((sbp)->sb_features2 &XFS_SB_VERSION2_FUNBIT)
*/
This should be updated to the lowe case convention inlines we've used for a long time. Or just removed as new features should go into v5 superblocks..
Modulo these minor bits:
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Re: [PATCH 1/5] xfs: make superblock version checks reflect reality
Quoted 8 lines · Christoph Hellwig
Quoted 8 lines
fs/xfs/xfs_sb.h +6
-0+/* +* The first XFS version we support is a v4 superblock with V2 directories. +*/ +static inline bool xfs_sb_good_v4_features (struct xfs_sb *sbp) { +if (!(sbp->sb_versionnum &XFS_SB_VERSION_DIRV2BIT )) +return false;
Quoted 6 lines
fs/xfs/xfs_sb.h typedef enum { · line 339
Quoted 2 lines
fs/xfs/xfs_sb.h +2
-0+/* check for unknown features in the fs */ + if ((sbp->sb_versionnum & ~XFS_SB_VERSION_OKBITS) ||Given that
sb_versionnumis a__uint16_tandXFS_SB_VERSION_OKBITSis0xffffthis will never evaluate to false and a sane compiler should warn about it. How about remove this check andXFS_SB_VERSION_OKBITS?
It gets changed later to this:
#define XFS_SB_VERSION_OKBITS \
((XFS_SB_VERSION_NUMBITS | XFS_SB_VERSION_ALLFBITS) & \
~XFS_SB_VERSION_SHAREDBIT)So we don't ever consider the shared bit valid. IOWs, it's not 0xffff ;)
Quoted 9 lines
The various
has_macros are a bit confusing to me, as some explicitly check for 5 superblocks, and some assume the caller handles them in some way, but I think this is something we can leave for later cleanups.Quoted 4 lines
* For example, for a bit defined as
XFS_SB_VERSION2_FUNBIT, has a macro:
*
- *SB_VERSION_HASFUNBIT(xfs_sb_t *sbp)
+ *SB_VERSION_HASFUNBIT(struct xfs_sb *sbp)
Quoted 7 lines
Quoted 3 lines
* ((
xfs_sb_version_hasmorebits(sbp)&&
* ((sbp)->sb_features2 &XFS_SB_VERSION2_FUNBIT)
*/This should be updated to the lowe case convention inlines we've used for a long time. Or just removed as new features should go into v5 superblocks..
I'll update it.
Quoted 3 lines
Modulo these minor bits:
Reviewed-by Christoph Hellwig <[email protected]>
Thanks!
Cheers,
Dave.
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Dave Chinner [email protected] _______________________________________________ xfs mailing list [email protected] http://oss.sgi.com/mailman/listinfo/xfs
PATCH 2/5 xfs: keep sb_bad_features2 the same a sb_features2
In reply to Dave ChinnerFrom: Dave Chinner <[email protected]>
Whenever we update sb_features2, we need to update sb_bad_features2 so that they remain identical on disk. This prevents future mounts or userspace utilities from getting confused over which features the filesystem supports.
--- fs/xfs/xfs_sb.h | 2 ++ 1 file changed, 2 insertions(+)
fs/xfs/xfs_sb.h +2 -0
@@ -475,11 +475,13 @@ static inline void xfs_sb_version_addattr2(struct xfs_sb *sbp) { sbp->sb_versionnum |=XFS_SB_VERSION_MOREBITSBIT ; sbp->sb_features2 |=XFS_SB_VERSION2_ATTR2BIT ; + sbp->sb_bad_features2 |=XFS_SB_VERSION2_ATTR2BIT ; }static inline void xfs_sb_version_removeattr2 (struct xfs_sb *sbp) { sbp->sb_features2 &= ~XFS_SB_VERSION2_ATTR2BIT ; + sbp->sb_bad_features2 &= ~XFS_SB_VERSION2_ATTR2BIT ;if (!sbp->sb_features2) sbp->sb_versionnum &= ~XFS_SB_VERSION_MOREBITSBIT ; }
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1.9.0 _______________________________________________ xfs mailing list [email protected] http://oss.sgi.com/mailman/listinfo/xfs
Re: [PATCH 2/5] xfs: keep sb_bad_features2 the same a sb_features2
Quoted 8 lines · Dave Chinner
From: Dave Chinner <[email protected]>
Whenever we update
sb_features2, we need to updatesb_bad_features2so that they remain identical on disk. This prevents future mounts or userspace utilities from getting confused over which features the filesystem supports.Signed-off-by Dave Chinner <[email protected]>
Looks good,
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PATCH 3/5 xfs: turn NLINK feature on by default
In reply to Dave ChinnerFrom: Dave Chinner <[email protected]>
mkfs has turned on the XFS_SB_VERSION_NLINKBIT feature bit by default since November 2007. It's about time we simply made the kernel code turn it on by default and so always convert v1 inodes to v2 inodes. This removes needless version checks and modification when bumping link counts on inodes, and will take code out of a few common code paths.
text data bss dec hex filename 783595 100867 616 885078 d8156 fs/xfs/xfs.o.orig 783171 100867 616 884654 d7fae fs/xfs/xfs.o.patched
--- fs/xfs/xfs_fsops.c | 4 +-- fs/xfs/xfs_ialloc.c | 4 +-- fs/xfs/xfs_inode.c | 80 +++++++++++-------------------------------------- fs/xfs/xfs_inode.h | 2 +- fs/xfs/xfs_inode_item.c | 30 +------------------ fs/xfs/xfs_ioctl.c | 5 ++-- fs/xfs/xfs_mount.c | 6 ++++ fs/xfs/xfs_sb.h | 10 ------- 8 files changed, 31 insertions(+), 110 deletions(-)
fs/xfs/xfs_fsops.c +1 -3
@@ -74,11 +74,9 @@ xfs_fs_geometry( }if (new_version >=3 ) { geo->version =XFS_FSOP_GEOM_VERSION ; - geo->flags = + geo->flags =XFS_FSOP_GEOM_FLAGS_NLINK | (xfs_sb_version_hasattr (&mp->m_sb) ?XFS_FSOP_GEOM_FLAGS_ATTR :0 ) | - (xfs_sb_version_hasnlink (&mp->m_sb) ? -XFS_FSOP_GEOM_FLAGS_NLINK :0 ) | (xfs_sb_version_hasquota (&mp->m_sb) ? XFS_FSOP_GEOM_FLAGS_QUOTA : 0) | (xfs_sb_version_hasalign(&mp->m_sb) ?
fs/xfs/xfs_ialloc.c +1 -3
@@ -280,10 +280,8 @@ xfs_ialloc_inode_init(if (tp)xfs_icreate_log (tp, agno, agbno, mp->m_ialloc_inos, mp->m_sb.sb_inodesize, length, gen); - }else if (xfs_sb_version_hasnlink (&mp->m_sb)) + }else version =2 ; -else - version =1 ;for (j =0 ; j < nbufs; j++) {/*
fs/xfs/xfs_inode.c +18 -62
120 lines not on this page · raw message
fs/xfs/xfs_inode.h +1 -1
@@ -377,7 +377,7 @@ int xfs_dir_ialloc(struct xfs_trans **, struct xfs_inode *, umode_t, struct xfs_inode **, int *);int xfs_droplink (struct xfs_trans *,struct xfs_inode *);int xfs_bumplink (struct xfs_trans *,struct xfs_inode *); -void xfs_bump_ino_vers2 (struct xfs_trans *,struct xfs_inode *); +void xfs_bump_ino_vers2 (struct xfs_inode *);/* from xfs_file.c */ int xfs_zero_eof (struct xfs_inode *,xfs_off_t ,xfs_fsize_t );
fs/xfs/xfs_inode_item.c +1 -29
@@ -145,34 +145,6 @@ xfs_inode_item_size(xfs_inode_item_attr_fork_size (iip, nvecs, nbytes); } -/* -* If this is a v1 format inode, then we need to log it as such. This means -* that we have to copy the link count from the new field to the old. We -* don't have to worry about the new fields, because nothing trusts them as -* long as the old inode version number is there. -*/ -STATIC void -xfs_inode_item_format_v1_inode ( -struct xfs_inode *ip) -{ -if (!xfs_sb_version_hasnlink (&ip->i_mount->m_sb)) { -/* -* Convert it back. -*/ -ASSERT (ip->i_d.di_nlink <=XFS_MAXLINK_1 ); - ip->i_d.di_onlink = ip->i_d.di_nlink; - }else { -/* -* The superblock version has already been bumped, -* so just make the conversion to the new inode -* format permanent. -*/ - ip->i_d.di_version =2 ; - ip->i_d.di_onlink =0 ; -memset (&(ip->i_d.di_pad[0 ]),0 ,sizeof (ip->i_d.di_pad)); - } -} - STATIC void xfs_inode_item_format_data_fork( struct xfs_inode_log_item *iip,
@@ -381,7 +353,7 @@ xfs_inode_item_format(xlog_finish_iovec (lv, vecp,sizeof (struct xfs_inode_log_format ));if (ip->i_d.di_version ==1 ) -xfs_inode_item_format_v1_inode (ip); +xfs_bump_ino_vers2 (ip);xlog_copy_iovec (lv, &vecp,XLOG_REG_TYPE_ICORE , &ip->i_d,xfs_icdinode_size (ip->i_d.di_version));
fs/xfs/xfs_ioctl.c +3 -2
@@ -1228,7 +1228,6 @@ xfs_ioctl_setattr( olddquot =xfs_qm_vop_chown (tp, ip, &ip->i_pdquot, pdqp); } -xfs_set_projid (ip, fa->fsx_projid);/* * We may have to rev the inode as well as
@@ -1236,7 +1235,9 @@ xfs_ioctl_setattr(* exist before DINODE_VERSION_2 and SB_VERSION_NLINK. */ if (ip->i_d.di_version ==1 ) -xfs_bump_ino_vers2 (tp, ip); +xfs_bump_ino_vers2 (ip); + +xfs_set_projid (ip, fa->fsx_projid); } }
fs/xfs/xfs_mount.c +6 -0
@@ -697,6 +697,12 @@ xfs_mountfs( mp->m_update_flags |=XFS_SB_VERSIONNUM ; } +/* always use v2 inodes by default now */ +if (!(mp->m_sb.sb_versionnum &XFS_SB_VERSION_NLINKBIT )) { + mp->m_sb.sb_versionnum |=XFS_SB_VERSION_NLINKBIT ; + mp->m_update_flags |=XFS_SB_VERSIONNUM ; + } +/* * Check if sb_agblocks is aligned at stripe boundary * If sb_agblocks is NOT aligned turn off m_dalign since
fs/xfs/xfs_sb.h +0 -10
@@ -376,16 +376,6 @@ static inline void xfs_sb_version_addattr(struct xfs_sb *sbp) sbp->sb_versionnum |=XFS_SB_VERSION_ATTRBIT ; } -static inline bool xfs_sb_version_hasnlink (struct xfs_sb *sbp) -{ -return (sbp->sb_versionnum &XFS_SB_VERSION_NLINKBIT ); -} - -static inline void xfs_sb_version_addnlink (struct xfs_sb *sbp) -{ - sbp->sb_versionnum |=XFS_SB_VERSION_NLINKBIT ; -} -static inline bool xfs_sb_version_hasquota (struct xfs_sb *sbp) {return (sbp->sb_versionnum &XFS_SB_VERSION_QUOTABIT );
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1.9.0 _______________________________________________ xfs mailing list [email protected] http://oss.sgi.com/mailman/listinfo/xfs
Re: [PATCH 3/5] xfs: turn NLINK feature on by default
fs/xfs/xfs_inode.c xfs_bumplink( · line 1088
Quoted 7 lines
fs/xfs/xfs_inode.c +1
-1@@ -1112,7 +1085,7 @@ xfs_bumplink(* system to do this, then we need to bump the superblock * version number as well. */ -xfs_bump_ino_vers2 (tp, ip); +xfs_bump_ino_vers2 (ip);
The comment here is certainly out of date now.
But I think keeping these xfs_bump_ino_vers2 calls around everywhere is wrong to start with. xfs_iread should make sure all inodes are version 1, that allows to kill xfs_bump_ino_vers2 entirely, and probably also simplify xfs_ialloc a little more. At the point we won't have to deal with v1 inodes anywhere but in xfs_iread, and we can have a big fat comment in that place why we even bother with the v1 inodes, because the fact that we have the hasnlink bit but inodes might still be old format is something we'll all have forgotten about in a few years, and new developers will never figure out by themselves.
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Re: [PATCH 3/5] xfs: turn NLINK feature on by default
Quoted 10 lines · Christoph Hellwig
fs/xfs/xfs_inode.c xfs_bumplink( · line 1088
Quoted 7 lines
fs/xfs/xfs_inode.c +1
-1@@ -1112,7 +1085,7 @@ xfs_bumplink(* system to do this, then we need to bump the superblock * version number as well. */ -xfs_bump_ino_vers2 (tp, ip); +xfs_bump_ino_vers2 (ip);The comment here is certainly out of date now.
Quoted 9 lines
But I think keeping these
xfs_bump_ino_vers2calls around everywhere is wrong to start with.xfs_ireadshould make sure all inodes are version 1, that allows to killxfs_bump_ino_vers2entirely, and probably also simplifyxfs_ialloca little more. At the point we won't have to deal with v1 inodes anywhere but inxfs_iread, and we can have a big fat comment in that place why we even bother with the v1 inodes, because the fact that we have the hasnlink bit but inodes might still be old format is something we'll all have forgotten about in a few years, and new developers will never figure out by themselves.
OK, I'll look at reworking it aong those lines.
Cheers,
Dave.
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Dave Chinner [email protected] _______________________________________________ xfs mailing list [email protected] http://oss.sgi.com/mailman/listinfo/xfs
PATCH 4/5 xfs: don't need dirv2 checks anymore
In reply to Dave ChinnerFrom: Dave Chinner <[email protected]>
If the the V2 directory feature bit is not set in the superblock feature mask the filesystem will fail the good version check. Hence we don't need any other version checking on the dir2 feature bit in the code as the filesystem will not mount without it set. Remove the checking code.
--- fs/xfs/xfs_dir2.c | 2 +- fs/xfs/xfs_fsops.c | 3 +-- fs/xfs/xfs_sb.c | 9 --------- fs/xfs/xfs_sb.h | 6 ------ 4 files changed, 2 insertions(+), 18 deletions(-)
fs/xfs/xfs_dir2.c +1 -1
@@ -92,7 +92,7 @@ xfs_dir_mount(int nodehdr_size; -ASSERT (xfs_sb_version_hasdirv2 (&mp->m_sb)); +ASSERT (mp->m_sb.sb_versionnum &XFS_SB_VERSION_DIRV2BIT );ASSERT ((1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) <=XFS_MAX_BLOCKSIZE );
fs/xfs/xfs_fsops.c +1 -2
@@ -75,6 +75,7 @@ xfs_fs_geometry(if (new_version >=3 ) { geo->version =XFS_FSOP_GEOM_VERSION ; geo->flags =XFS_FSOP_GEOM_FLAGS_NLINK | +XFS_FSOP_GEOM_FLAGS_DIRV2 | (xfs_sb_version_hasattr (&mp->m_sb) ? XFS_FSOP_GEOM_FLAGS_ATTR : 0) | (xfs_sb_version_hasquota(&mp->m_sb) ?
@@ -87,8 +88,6 @@ xfs_fs_geometry( XFS_FSOP_GEOM_FLAGS_SHARED : 0) | (xfs_sb_version_hasextflgbit (&mp->m_sb) ?XFS_FSOP_GEOM_FLAGS_EXTFLG :0 ) | - (xfs_sb_version_hasdirv2 (&mp->m_sb) ? -XFS_FSOP_GEOM_FLAGS_DIRV2 :0 ) | (xfs_sb_version_hassector (&mp->m_sb) ? XFS_FSOP_GEOM_FLAGS_SECTOR : 0) | (xfs_sb_version_hasasciici(&mp->m_sb) ?
fs/xfs/xfs_sb.c +0 -9
@@ -333,15 +333,6 @@ xfs_mount_validate_sb(xfs_warn (mp,"Offline file system operation in progress!" );return XFS_ERROR (EFSCORRUPTED ); } - -/* -* Version 1 directory format has never worked on Linux. -*/ -if (unlikely (!xfs_sb_version_hasdirv2 (sbp))) { -xfs_warn (mp,"file system using version 1 directory format" ); -return XFS_ERROR (ENOSYS ); - } -return 0 ; }
fs/xfs/xfs_sb.h +0 -6
@@ -403,12 +403,6 @@ static inline bool xfs_sb_version_hasshared(struct xfs_sb *sbp) (sbp->sb_versionnum &XFS_SB_VERSION_SHAREDBIT ); } -static inline bool xfs_sb_version_hasdirv2 (struct xfs_sb *sbp) -{ -return XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_5 || - (sbp->sb_versionnum &XFS_SB_VERSION_DIRV2BIT ); -} -static inline bool xfs_sb_version_haslogv2 (struct xfs_sb *sbp) { return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 ||
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Re: [PATCH 4/5] xfs: don't need dirv2 checks anymore
fs/xfs/xfs_dir2.c xfs_dir_mount( · line 95
Quoted 2 lines
fs/xfs/xfs_dir2.c +1
-1-ASSERT (xfs_sb_version_hasdirv2 (&mp->m_sb)); +ASSERT (mp->m_sb.sb_versionnum &XFS_SB_VERSION_DIRV2BIT );
How is this going to work for v5 filesystems? Probably better to just kill the assert..
Otherwise looks good,
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Re: [PATCH 4/5] xfs: don't need dirv2 checks anymore
Quoted 5 lines · Christoph Hellwig
fs/xfs/xfs_dir2.c xfs_dir_mount( · line 95
Quoted 2 lines
fs/xfs/xfs_dir2.c +1
-1-ASSERT (xfs_sb_version_hasdirv2 (&mp->m_sb)); +ASSERT (mp->m_sb.sb_versionnum &XFS_SB_VERSION_DIRV2BIT );How is this going to work for v5 filesystems? Probably better to just kill the assert..
mkfs still sets the sb_features bitmask for all the supported v4 features it uses by default on v5 superblocks. There are some feature bits in the v4 mask that are optional for v5 superblocks, too (e.g. case insensitivity, sunit/swidth alignment), so we won't ever stop setting the XFS_SB_VERSION_DIRV2BIT on v5 superblocks...
Quoted 3 lines
Otherwise looks good,
Reviewed-by Christoph Hellwig <[email protected]>
Thanks!
Cheers,
Dave.
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Dave Chinner [email protected] _______________________________________________ xfs mailing list [email protected] http://oss.sgi.com/mailman/listinfo/xfs
PATCH 5/5 xfs: remove shared supberlock feature checking
In reply to Dave ChinnerFrom: Dave Chinner <[email protected]>
We reject any filesystem that is mounted with this feature bit set, so we don't need to check for it anywhere else. Remove the function for checking if the feature bit is set and any code that uses it.
--- fs/xfs/xfs_fsops.c | 2 -- fs/xfs/xfs_sb.c | 3 ++- fs/xfs/xfs_sb.h | 17 ++++------------- 3 files changed, 6 insertions(+), 16 deletions(-)
fs/xfs/xfs_fsops.c +0 -2
@@ -84,8 +84,6 @@ xfs_fs_geometry( XFS_FSOP_GEOM_FLAGS_IALIGN : 0) | (xfs_sb_version_hasdalign (&mp->m_sb) ?XFS_FSOP_GEOM_FLAGS_DALIGN :0 ) | - (xfs_sb_version_hasshared (&mp->m_sb) ? -XFS_FSOP_GEOM_FLAGS_SHARED :0 ) | (xfs_sb_version_hasextflgbit (&mp->m_sb) ? XFS_FSOP_GEOM_FLAGS_EXTFLG : 0) | (xfs_sb_version_hassector(&mp->m_sb) ?
fs/xfs/xfs_sb.c +2 -1
@@ -291,7 +291,8 @@ xfs_mount_validate_sb( (sbp->sb_imax_pct > 100 /* zero sb_imax_pct is valid */) || sbp->sb_dblocks == 0 || sbp->sb_dblocks > XFS_MAX_DBLOCKS(sbp) || - sbp->sb_dblocks < XFS_MIN_DBLOCKS(sbp))) { + sbp->sb_dblocks < XFS_MIN_DBLOCKS(sbp) || + sbp->sb_shared_vn != 0)) {xfs_notice (mp,"SB sanity check failed" );return XFS_ERROR (EFSCORRUPTED ); }
fs/xfs/xfs_sb.h +4 -13
@@ -51,11 +51,12 @@ struct xfs_trans;/* * Supported feature bit list is just all bits in the versionnum field because -* we've used them all up and understand them all. +* we've used them all up and understand them all. Except, of course, for the +* shared superblock bit, which nobody knows what it does and so is unsupported. */ #define XFS_SB_VERSION_OKBITS \ - (XFS_SB_VERSION_NUMBITS | \ - XFS_SB_VERSION_ALLFBITS) + ((XFS_SB_VERSION_NUMBITS | XFS_SB_VERSION_ALLFBITS) & \ + ~XFS_SB_VERSION_SHAREDBIT)/* * There are two words to hold XFS "feature" bits: the original
@@ -341,10 +342,6 @@ static inline bool xfs_sb_good_v4_features(struct xfs_sb *sbp) (sbp->sb_features2 & ~XFS_SB_VERSION2_OKBITS)))return false; -/* We don't support shared superblocks - nobody knows what it is */ -if (sbp->sb_versionnum &XFS_SB_VERSION_SHAREDBIT ) -return false; -return true; }
@@ -397,12 +394,6 @@ static inline bool xfs_sb_version_hasdalign(struct xfs_sb *sbp)return (sbp->sb_versionnum &XFS_SB_VERSION_DALIGNBIT ); } -static inline bool xfs_sb_version_hasshared (struct xfs_sb *sbp) -{ -return XFS_SB_VERSION_NUM (sbp) ==XFS_SB_VERSION_4 && - (sbp->sb_versionnum &XFS_SB_VERSION_SHAREDBIT ); -} -static inline bool xfs_sb_version_haslogv2 (struct xfs_sb *sbp) { return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 ||
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Re: [PATCH 5/5] xfs: remove shared supberlock feature checking
Quoted 18 lines · Dave Chinner
From: Dave Chinner <[email protected]>
We reject any filesystem that is mounted with this feature bit set, so we don't need to check for it anywhere else. Remove the function for checking if the feature bit is set and any code that uses it.
Signed-off-by Dave Chinner <[email protected]>--- fs/xfs/xfs_fsops.c | 2 -- fs/xfs/xfs_sb.c | 3 ++- fs/xfs/xfs_sb.h | 17 ++++------------- 3 files changed, 6 insertions(+), 16 deletions(-)fs/xfs/xfs_fsops.c +0
-0
fs/xfs/xfs_fsops.c xfs_fs_geometry( · line 88
Quoted 5 lines
fs/xfs/xfs_fsops.c +0
-2@@ -84,8 +84,6 @@ xfs_fs_geometry( XFS_FSOP_GEOM_FLAGS_IALIGN : 0) | (xfs_sb_version_hasdalign (&mp->m_sb) ? XFS_FSOP_GEOM_FLAGS_DALIGN : 0) | - (xfs_sb_version_hasshared (&mp->m_sb) ? - XFS_FSOP_GEOM_FLAGS_SHARED : 0) |
Just a trivial comments, now the XFS_FSOP_GEOM_FLAGS_SHARED is useless, so we can remove it from fs/xfs/xfs.h.
Otherwise, looks good to me.
Cheers,
-Jeff
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Re: [PATCH 5/5] xfs: remove shared supberlock feature checking
Quoted 15 lines · Jeff Liu
Quoted 13 lines · Dave Chinner
From: Dave Chinner <[email protected]>
We reject any filesystem that is mounted with this feature bit set, so we don't need to check for it anywhere else. Remove the function for checking if the feature bit is set and any code that uses it.
Signed-off-by Dave Chinner <[email protected]>--- fs/xfs/xfs_fsops.c | 2 -- fs/xfs/xfs_sb.c | 3 ++- fs/xfs/xfs_sb.h | 17 ++++------------- 3 files changed, 6 insertions(+), 16 deletions(-)
Quoted 13 lines
fs/xfs/xfs_fsops.c xfs_fs_geometry( · line 88
Quoted 10 lines
fs/xfs/xfs_fsops.c +0
-2@@ -84,8 +84,6 @@ xfs_fs_geometry( XFS_FSOP_GEOM_FLAGS_IALIGN : 0) | (xfs_sb_version_hasdalign (&mp->m_sb) ? XFS_FSOP_GEOM_FLAGS_DALIGN : 0) | - (xfs_sb_version_hasshared (&mp->m_sb) ? - XFS_FSOP_GEOM_FLAGS_SHARED : 0) |Just a trivial comments, now the
XFS_FSOP_GEOM_FLAGS_SHAREDis useless, so we can remove it fromfs/xfs/xfs.h.
That's a public API header file, so removing it could break applications. It's OK to leave it there, I think.
Quoted 3 lines
Otherwise, looks good to me.
Reviewed-by Jie Liu <[email protected]>
Thanks!
Cheers,
Dave.
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Re: [PATCH 5/5] xfs: remove shared supberlock feature checking
In reply to Dave ChinnerQuoted 6 lines · Dave Chinner
We reject any filesystem that is mounted with this feature bit set, so we don't need to check for it anywhere else. Remove the function for checking if the feature bit is set and any code that uses it.
Signed-off-by Dave Chinner <[email protected]>
Looks good,
If someone at SGI has some spare time for a BugWorks search I'd really love to figure out of the story behind the shared superblock feature..
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Re: [PATCH 5/5] xfs: remove shared supberlock feature checking
Quoted 6 lines · Christoph Hellwig
Quoted 5 lines · Dave Chinner
We reject any filesystem that is mounted with this feature bit set, so we don't need to check for it anywhere else. Remove the function for checking if the feature bit is set and any code that uses it.
Quoted 8 lines
Quoted 1 line
Signed-off-by Dave Chinner <[email protected]>Looks good,
Reviewed-by Christoph Hellwig <[email protected]>If someone at SGI has some spare time for a BugWorks search I'd really love to figure out of the story behind the shared superblock feature..
tells us that the PV to start looking at is 522678. It's something to do with shared read-only filesystems - I suspect the sb_shared_vn field counts the number of read-only mounts - and my guess is it was for Cellular Irix. i.e. SGI's aborted attempt to make a distributed operating system that left useless crap all through the Irix 6.5 codebase...
Cheers,
Dve.
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