https://github.com/torvalds/linux
Tip revision: d72e90f33aa4709ebecc5005562f52335e106a60 authored by Linus Torvalds on 22 July 2018, 21:12:20 UTC
Linux 4.18-rc6
Linux 4.18-rc6
Tip revision: d72e90f
xfs_itable.c
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_ialloc_btree.h"
#include "xfs_itable.h"
#include "xfs_error.h"
#include "xfs_trace.h"
#include "xfs_icache.h"
/*
* Return stat information for one inode.
* Return 0 if ok, else errno.
*/
int
xfs_bulkstat_one_int(
struct xfs_mount *mp, /* mount point for filesystem */
xfs_ino_t ino, /* inode to get data for */
void __user *buffer, /* buffer to place output in */
int ubsize, /* size of buffer */
bulkstat_one_fmt_pf formatter, /* formatter, copy to user */
int *ubused, /* bytes used by me */
int *stat) /* BULKSTAT_RV_... */
{
struct xfs_icdinode *dic; /* dinode core info pointer */
struct xfs_inode *ip; /* incore inode pointer */
struct inode *inode;
struct xfs_bstat *buf; /* return buffer */
int error = 0; /* error value */
*stat = BULKSTAT_RV_NOTHING;
if (!buffer || xfs_internal_inum(mp, ino))
return -EINVAL;
buf = kmem_zalloc(sizeof(*buf), KM_SLEEP | KM_MAYFAIL);
if (!buf)
return -ENOMEM;
error = xfs_iget(mp, NULL, ino,
(XFS_IGET_DONTCACHE | XFS_IGET_UNTRUSTED),
XFS_ILOCK_SHARED, &ip);
if (error)
goto out_free;
ASSERT(ip != NULL);
ASSERT(ip->i_imap.im_blkno != 0);
inode = VFS_I(ip);
dic = &ip->i_d;
/* xfs_iget returns the following without needing
* further change.
*/
buf->bs_projid_lo = dic->di_projid_lo;
buf->bs_projid_hi = dic->di_projid_hi;
buf->bs_ino = ino;
buf->bs_uid = dic->di_uid;
buf->bs_gid = dic->di_gid;
buf->bs_size = dic->di_size;
buf->bs_nlink = inode->i_nlink;
buf->bs_atime.tv_sec = inode->i_atime.tv_sec;
buf->bs_atime.tv_nsec = inode->i_atime.tv_nsec;
buf->bs_mtime.tv_sec = inode->i_mtime.tv_sec;
buf->bs_mtime.tv_nsec = inode->i_mtime.tv_nsec;
buf->bs_ctime.tv_sec = inode->i_ctime.tv_sec;
buf->bs_ctime.tv_nsec = inode->i_ctime.tv_nsec;
buf->bs_gen = inode->i_generation;
buf->bs_mode = inode->i_mode;
buf->bs_xflags = xfs_ip2xflags(ip);
buf->bs_extsize = dic->di_extsize << mp->m_sb.sb_blocklog;
buf->bs_extents = dic->di_nextents;
memset(buf->bs_pad, 0, sizeof(buf->bs_pad));
buf->bs_dmevmask = dic->di_dmevmask;
buf->bs_dmstate = dic->di_dmstate;
buf->bs_aextents = dic->di_anextents;
buf->bs_forkoff = XFS_IFORK_BOFF(ip);
if (dic->di_version == 3) {
if (dic->di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
buf->bs_cowextsize = dic->di_cowextsize <<
mp->m_sb.sb_blocklog;
}
switch (dic->di_format) {
case XFS_DINODE_FMT_DEV:
buf->bs_rdev = sysv_encode_dev(inode->i_rdev);
buf->bs_blksize = BLKDEV_IOSIZE;
buf->bs_blocks = 0;
break;
case XFS_DINODE_FMT_LOCAL:
buf->bs_rdev = 0;
buf->bs_blksize = mp->m_sb.sb_blocksize;
buf->bs_blocks = 0;
break;
case XFS_DINODE_FMT_EXTENTS:
case XFS_DINODE_FMT_BTREE:
buf->bs_rdev = 0;
buf->bs_blksize = mp->m_sb.sb_blocksize;
buf->bs_blocks = dic->di_nblocks + ip->i_delayed_blks;
break;
}
xfs_iunlock(ip, XFS_ILOCK_SHARED);
IRELE(ip);
error = formatter(buffer, ubsize, ubused, buf);
if (!error)
*stat = BULKSTAT_RV_DIDONE;
out_free:
kmem_free(buf);
return error;
}
/* Return 0 on success or positive error */
STATIC int
xfs_bulkstat_one_fmt(
void __user *ubuffer,
int ubsize,
int *ubused,
const xfs_bstat_t *buffer)
{
if (ubsize < sizeof(*buffer))
return -ENOMEM;
if (copy_to_user(ubuffer, buffer, sizeof(*buffer)))
return -EFAULT;
if (ubused)
*ubused = sizeof(*buffer);
return 0;
}
int
xfs_bulkstat_one(
xfs_mount_t *mp, /* mount point for filesystem */
xfs_ino_t ino, /* inode number to get data for */
void __user *buffer, /* buffer to place output in */
int ubsize, /* size of buffer */
int *ubused, /* bytes used by me */
int *stat) /* BULKSTAT_RV_... */
{
return xfs_bulkstat_one_int(mp, ino, buffer, ubsize,
xfs_bulkstat_one_fmt, ubused, stat);
}
/*
* Loop over all clusters in a chunk for a given incore inode allocation btree
* record. Do a readahead if there are any allocated inodes in that cluster.
*/
STATIC void
xfs_bulkstat_ichunk_ra(
struct xfs_mount *mp,
xfs_agnumber_t agno,
struct xfs_inobt_rec_incore *irec)
{
xfs_agblock_t agbno;
struct blk_plug plug;
int blks_per_cluster;
int inodes_per_cluster;
int i; /* inode chunk index */
agbno = XFS_AGINO_TO_AGBNO(mp, irec->ir_startino);
blks_per_cluster = xfs_icluster_size_fsb(mp);
inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
blk_start_plug(&plug);
for (i = 0; i < XFS_INODES_PER_CHUNK;
i += inodes_per_cluster, agbno += blks_per_cluster) {
if (xfs_inobt_maskn(i, inodes_per_cluster) & ~irec->ir_free) {
xfs_btree_reada_bufs(mp, agno, agbno, blks_per_cluster,
&xfs_inode_buf_ops);
}
}
blk_finish_plug(&plug);
}
/*
* Lookup the inode chunk that the given inode lives in and then get the record
* if we found the chunk. If the inode was not the last in the chunk and there
* are some left allocated, update the data for the pointed-to record as well as
* return the count of grabbed inodes.
*/
STATIC int
xfs_bulkstat_grab_ichunk(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_agino_t agino, /* starting inode of chunk */
int *icount,/* return # of inodes grabbed */
struct xfs_inobt_rec_incore *irec) /* btree record */
{
int idx; /* index into inode chunk */
int stat;
int error = 0;
/* Lookup the inode chunk that this inode lives in */
error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &stat);
if (error)
return error;
if (!stat) {
*icount = 0;
return error;
}
/* Get the record, should always work */
error = xfs_inobt_get_rec(cur, irec, &stat);
if (error)
return error;
XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, stat == 1);
/* Check if the record contains the inode in request */
if (irec->ir_startino + XFS_INODES_PER_CHUNK <= agino) {
*icount = 0;
return 0;
}
idx = agino - irec->ir_startino + 1;
if (idx < XFS_INODES_PER_CHUNK &&
(xfs_inobt_maskn(idx, XFS_INODES_PER_CHUNK - idx) & ~irec->ir_free)) {
int i;
/* We got a right chunk with some left inodes allocated at it.
* Grab the chunk record. Mark all the uninteresting inodes
* free -- because they're before our start point.
*/
for (i = 0; i < idx; i++) {
if (XFS_INOBT_MASK(i) & ~irec->ir_free)
irec->ir_freecount++;
}
irec->ir_free |= xfs_inobt_maskn(0, idx);
*icount = irec->ir_count - irec->ir_freecount;
}
return 0;
}
#define XFS_BULKSTAT_UBLEFT(ubleft) ((ubleft) >= statstruct_size)
struct xfs_bulkstat_agichunk {
char __user **ac_ubuffer;/* pointer into user's buffer */
int ac_ubleft; /* bytes left in user's buffer */
int ac_ubelem; /* spaces used in user's buffer */
};
/*
* Process inodes in chunk with a pointer to a formatter function
* that will iget the inode and fill in the appropriate structure.
*/
static int
xfs_bulkstat_ag_ichunk(
struct xfs_mount *mp,
xfs_agnumber_t agno,
struct xfs_inobt_rec_incore *irbp,
bulkstat_one_pf formatter,
size_t statstruct_size,
struct xfs_bulkstat_agichunk *acp,
xfs_agino_t *last_agino)
{
char __user **ubufp = acp->ac_ubuffer;
int chunkidx;
int error = 0;
xfs_agino_t agino = irbp->ir_startino;
for (chunkidx = 0; chunkidx < XFS_INODES_PER_CHUNK;
chunkidx++, agino++) {
int fmterror;
int ubused;
/* inode won't fit in buffer, we are done */
if (acp->ac_ubleft < statstruct_size)
break;
/* Skip if this inode is free */
if (XFS_INOBT_MASK(chunkidx) & irbp->ir_free)
continue;
/* Get the inode and fill in a single buffer */
ubused = statstruct_size;
error = formatter(mp, XFS_AGINO_TO_INO(mp, agno, agino),
*ubufp, acp->ac_ubleft, &ubused, &fmterror);
if (fmterror == BULKSTAT_RV_GIVEUP ||
(error && error != -ENOENT && error != -EINVAL)) {
acp->ac_ubleft = 0;
ASSERT(error);
break;
}
/* be careful not to leak error if at end of chunk */
if (fmterror == BULKSTAT_RV_NOTHING || error) {
error = 0;
continue;
}
*ubufp += ubused;
acp->ac_ubleft -= ubused;
acp->ac_ubelem++;
}
/*
* Post-update *last_agino. At this point, agino will always point one
* inode past the last inode we processed successfully. Hence we
* substract that inode when setting the *last_agino cursor so that we
* return the correct cookie to userspace. On the next bulkstat call,
* the inode under the lastino cookie will be skipped as we have already
* processed it here.
*/
*last_agino = agino - 1;
return error;
}
/*
* Return stat information in bulk (by-inode) for the filesystem.
*/
int /* error status */
xfs_bulkstat(
xfs_mount_t *mp, /* mount point for filesystem */
xfs_ino_t *lastinop, /* last inode returned */
int *ubcountp, /* size of buffer/count returned */
bulkstat_one_pf formatter, /* func that'd fill a single buf */
size_t statstruct_size, /* sizeof struct filling */
char __user *ubuffer, /* buffer with inode stats */
int *done) /* 1 if there are more stats to get */
{
xfs_buf_t *agbp; /* agi header buffer */
xfs_agino_t agino; /* inode # in allocation group */
xfs_agnumber_t agno; /* allocation group number */
xfs_btree_cur_t *cur; /* btree cursor for ialloc btree */
xfs_inobt_rec_incore_t *irbuf; /* start of irec buffer */
int nirbuf; /* size of irbuf */
int ubcount; /* size of user's buffer */
struct xfs_bulkstat_agichunk ac;
int error = 0;
/*
* Get the last inode value, see if there's nothing to do.
*/
agno = XFS_INO_TO_AGNO(mp, *lastinop);
agino = XFS_INO_TO_AGINO(mp, *lastinop);
if (agno >= mp->m_sb.sb_agcount ||
*lastinop != XFS_AGINO_TO_INO(mp, agno, agino)) {
*done = 1;
*ubcountp = 0;
return 0;
}
ubcount = *ubcountp; /* statstruct's */
ac.ac_ubuffer = &ubuffer;
ac.ac_ubleft = ubcount * statstruct_size; /* bytes */;
ac.ac_ubelem = 0;
*ubcountp = 0;
*done = 0;
irbuf = kmem_zalloc_large(PAGE_SIZE * 4, KM_SLEEP);
if (!irbuf)
return -ENOMEM;
nirbuf = (PAGE_SIZE * 4) / sizeof(*irbuf);
/*
* Loop over the allocation groups, starting from the last
* inode returned; 0 means start of the allocation group.
*/
while (agno < mp->m_sb.sb_agcount) {
struct xfs_inobt_rec_incore *irbp = irbuf;
struct xfs_inobt_rec_incore *irbufend = irbuf + nirbuf;
bool end_of_ag = false;
int icount = 0;
int stat;
error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
if (error)
break;
/*
* Allocate and initialize a btree cursor for ialloc btree.
*/
cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno,
XFS_BTNUM_INO);
if (agino > 0) {
/*
* In the middle of an allocation group, we need to get
* the remainder of the chunk we're in.
*/
struct xfs_inobt_rec_incore r;
error = xfs_bulkstat_grab_ichunk(cur, agino, &icount, &r);
if (error)
goto del_cursor;
if (icount) {
irbp->ir_startino = r.ir_startino;
irbp->ir_holemask = r.ir_holemask;
irbp->ir_count = r.ir_count;
irbp->ir_freecount = r.ir_freecount;
irbp->ir_free = r.ir_free;
irbp++;
}
/* Increment to the next record */
error = xfs_btree_increment(cur, 0, &stat);
} else {
/* Start of ag. Lookup the first inode chunk */
error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &stat);
}
if (error || stat == 0) {
end_of_ag = true;
goto del_cursor;
}
/*
* Loop through inode btree records in this ag,
* until we run out of inodes or space in the buffer.
*/
while (irbp < irbufend && icount < ubcount) {
struct xfs_inobt_rec_incore r;
error = xfs_inobt_get_rec(cur, &r, &stat);
if (error || stat == 0) {
end_of_ag = true;
goto del_cursor;
}
/*
* If this chunk has any allocated inodes, save it.
* Also start read-ahead now for this chunk.
*/
if (r.ir_freecount < r.ir_count) {
xfs_bulkstat_ichunk_ra(mp, agno, &r);
irbp->ir_startino = r.ir_startino;
irbp->ir_holemask = r.ir_holemask;
irbp->ir_count = r.ir_count;
irbp->ir_freecount = r.ir_freecount;
irbp->ir_free = r.ir_free;
irbp++;
icount += r.ir_count - r.ir_freecount;
}
error = xfs_btree_increment(cur, 0, &stat);
if (error || stat == 0) {
end_of_ag = true;
goto del_cursor;
}
cond_resched();
}
/*
* Drop the btree buffers and the agi buffer as we can't hold any
* of the locks these represent when calling iget. If there is a
* pending error, then we are done.
*/
del_cursor:
xfs_btree_del_cursor(cur, error ?
XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
xfs_buf_relse(agbp);
if (error)
break;
/*
* Now format all the good inodes into the user's buffer. The
* call to xfs_bulkstat_ag_ichunk() sets up the agino pointer
* for the next loop iteration.
*/
irbufend = irbp;
for (irbp = irbuf;
irbp < irbufend && ac.ac_ubleft >= statstruct_size;
irbp++) {
error = xfs_bulkstat_ag_ichunk(mp, agno, irbp,
formatter, statstruct_size, &ac,
&agino);
if (error)
break;
cond_resched();
}
/*
* If we've run out of space or had a formatting error, we
* are now done
*/
if (ac.ac_ubleft < statstruct_size || error)
break;
if (end_of_ag) {
agno++;
agino = 0;
}
}
/*
* Done, we're either out of filesystem or space to put the data.
*/
kmem_free(irbuf);
*ubcountp = ac.ac_ubelem;
/*
* We found some inodes, so clear the error status and return them.
* The lastino pointer will point directly at the inode that triggered
* any error that occurred, so on the next call the error will be
* triggered again and propagated to userspace as there will be no
* formatted inodes in the buffer.
*/
if (ac.ac_ubelem)
error = 0;
/*
* If we ran out of filesystem, lastino will point off the end of
* the filesystem so the next call will return immediately.
*/
*lastinop = XFS_AGINO_TO_INO(mp, agno, agino);
if (agno >= mp->m_sb.sb_agcount)
*done = 1;
return error;
}
int
xfs_inumbers_fmt(
void __user *ubuffer, /* buffer to write to */
const struct xfs_inogrp *buffer, /* buffer to read from */
long count, /* # of elements to read */
long *written) /* # of bytes written */
{
if (copy_to_user(ubuffer, buffer, count * sizeof(*buffer)))
return -EFAULT;
*written = count * sizeof(*buffer);
return 0;
}
/*
* Return inode number table for the filesystem.
*/
int /* error status */
xfs_inumbers(
struct xfs_mount *mp,/* mount point for filesystem */
xfs_ino_t *lastino,/* last inode returned */
int *count,/* size of buffer/count returned */
void __user *ubuffer,/* buffer with inode descriptions */
inumbers_fmt_pf formatter)
{
xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, *lastino);
xfs_agino_t agino = XFS_INO_TO_AGINO(mp, *lastino);
struct xfs_btree_cur *cur = NULL;
struct xfs_buf *agbp = NULL;
struct xfs_inogrp *buffer;
int bcount;
int left = *count;
int bufidx = 0;
int error = 0;
*count = 0;
if (agno >= mp->m_sb.sb_agcount ||
*lastino != XFS_AGINO_TO_INO(mp, agno, agino))
return error;
bcount = min(left, (int)(PAGE_SIZE / sizeof(*buffer)));
buffer = kmem_zalloc(bcount * sizeof(*buffer), KM_SLEEP);
do {
struct xfs_inobt_rec_incore r;
int stat;
if (!agbp) {
error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
if (error)
break;
cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno,
XFS_BTNUM_INO);
error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_GE,
&stat);
if (error)
break;
if (!stat)
goto next_ag;
}
error = xfs_inobt_get_rec(cur, &r, &stat);
if (error)
break;
if (!stat)
goto next_ag;
agino = r.ir_startino + XFS_INODES_PER_CHUNK - 1;
buffer[bufidx].xi_startino =
XFS_AGINO_TO_INO(mp, agno, r.ir_startino);
buffer[bufidx].xi_alloccount = r.ir_count - r.ir_freecount;
buffer[bufidx].xi_allocmask = ~r.ir_free;
if (++bufidx == bcount) {
long written;
error = formatter(ubuffer, buffer, bufidx, &written);
if (error)
break;
ubuffer += written;
*count += bufidx;
bufidx = 0;
}
if (!--left)
break;
error = xfs_btree_increment(cur, 0, &stat);
if (error)
break;
if (stat)
continue;
next_ag:
xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
cur = NULL;
xfs_buf_relse(agbp);
agbp = NULL;
agino = 0;
agno++;
} while (agno < mp->m_sb.sb_agcount);
if (!error) {
if (bufidx) {
long written;
error = formatter(ubuffer, buffer, bufidx, &written);
if (!error)
*count += bufidx;
}
*lastino = XFS_AGINO_TO_INO(mp, agno, agino);
}
kmem_free(buffer);
if (cur)
xfs_btree_del_cursor(cur, (error ? XFS_BTREE_ERROR :
XFS_BTREE_NOERROR));
if (agbp)
xfs_buf_relse(agbp);
return error;
}