[PATCH 13/15] xfs: refactor INUMBERS to use iwalk functions

Darrick J. Wong
2019-06-26T20:45:34Z

Now that we have generic functions to walk inode records, refactor the
INUMBERS implementation to use it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
---
fs/xfs/xfs_ioctl.c | 20 ++++--
fs/xfs/xfs_ioctl.h | 2 +
fs/xfs/xfs_ioctl32.c | 35 ++++-------
fs/xfs/xfs_itable.c | 164 +++++++++++++++++++-------------------------------
fs/xfs/xfs_itable.h | 22 +------
5 files changed, 93 insertions(+), 150 deletions(-)

diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 60595e61f2a6..04b661ff0799 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -733,6 +733,16 @@ xfs_bulkstat_one_fmt(
return xfs_ibulk_advance(breq, sizeof(struct xfs_bstat));
}

+int
+xfs_inumbers_fmt(
+ struct xfs_ibulk *breq,
+ const struct xfs_inogrp *igrp)
+{
+ if (copy_to_user(breq->ubuffer, igrp, sizeof(*igrp)))
+ return -EFAULT;
+ return xfs_ibulk_advance(breq, sizeof(struct xfs_inogrp));
+}
+
STATIC int
xfs_ioc_bulkstat(
xfs_mount_t *mp,
@@ -783,13 +793,9 @@ xfs_ioc_bulkstat(
* in filesystem".
*/
if (cmd == XFS_IOC_FSINUMBERS) {
- int count = breq.icount;
-
- breq.startino = lastino;
- error = xfs_inumbers(mp, &breq.startino, &count,
- bulkreq.ubuffer, xfs_inumbers_fmt);
- breq.ocount = count;
- lastino = breq.startino;
+ breq.startino = lastino ? lastino + 1 : 0;
+ error = xfs_inumbers(&breq, xfs_inumbers_fmt);
+ lastino = breq.startino - 1;
} else if (cmd == XFS_IOC_FSBULKSTAT_SINGLE) {
breq.startino = lastino;
breq.icount = 1;
diff --git a/fs/xfs/xfs_ioctl.h b/fs/xfs/xfs_ioctl.h
index f32c8aadfeba..fb303eaa8863 100644
--- a/fs/xfs/xfs_ioctl.h
+++ b/fs/xfs/xfs_ioctl.h
@@ -79,7 +79,9 @@ xfs_set_dmattrs(

struct xfs_ibulk;
struct xfs_bstat;
+struct xfs_inogrp;

int xfs_bulkstat_one_fmt(struct xfs_ibulk *breq, const struct xfs_bstat *bstat);
+int xfs_inumbers_fmt(struct xfs_ibulk *breq, const struct xfs_inogrp *igrp);

#endif
diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c
index daeacd78cca6..f3949684c49c 100644
--- a/fs/xfs/xfs_ioctl32.c
+++ b/fs/xfs/xfs_ioctl32.c
@@ -87,22 +87,17 @@ xfs_compat_growfs_rt_copyin(

STATIC int
xfs_inumbers_fmt_compat(
- void __user *ubuffer,
- const struct xfs_inogrp *buffer,
- long count,
- long *written)
+ struct xfs_ibulk *breq,
+ const struct xfs_inogrp *igrp)
{
- compat_xfs_inogrp_t __user *p32 = ubuffer;
- long i;
+ struct compat_xfs_inogrp __user *p32 = breq->ubuffer;

- for (i = 0; i < count; i++) {
- if (put_user(buffer[i].xi_startino, &p32[i].xi_startino) ||
- put_user(buffer[i].xi_alloccount, &p32[i].xi_alloccount) ||
- put_user(buffer[i].xi_allocmask, &p32[i].xi_allocmask))
- return -EFAULT;
- }
- *written = count * sizeof(*p32);
- return 0;
+ if (put_user(igrp->xi_startino, &p32->xi_startino) ||
+ put_user(igrp->xi_alloccount, &p32->xi_alloccount) ||
+ put_user(igrp->xi_allocmask, &p32->xi_allocmask))
+ return -EFAULT;
+
+ return xfs_ibulk_advance(breq, sizeof(struct compat_xfs_inogrp));
}

#else
@@ -228,7 +223,7 @@ xfs_compat_ioc_bulkstat(
* to userpace memory via bulkreq.ubuffer. Normally the compat
* functions and structure size are the correct ones to use ...
*/
- inumbers_fmt_pf inumbers_func = xfs_inumbers_fmt_compat;
+ inumbers_fmt_pf inumbers_func = xfs_inumbers_fmt_compat;
bulkstat_one_fmt_pf bs_one_func = xfs_bulkstat_one_fmt_compat;

#ifdef CONFIG_X86_X32
@@ -290,13 +285,9 @@ xfs_compat_ioc_bulkstat(
* in filesystem".
*/
if (cmd == XFS_IOC_FSINUMBERS_32) {
- int count = breq.icount;
-
- breq.startino = lastino;
- error = xfs_inumbers(mp, &breq.startino, &count,
- bulkreq.ubuffer, inumbers_func);
- breq.ocount = count;
- lastino = breq.startino;
+ breq.startino = lastino ? lastino + 1 : 0;
+ error = xfs_inumbers(&breq, inumbers_func);
+ lastino = breq.startino - 1;
} else if (cmd == XFS_IOC_FSBULKSTAT_SINGLE_32) {
breq.startino = lastino;
breq.icount = 1;
diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
index a0603e7ed5dd..45f0618efb8d 100644
--- a/fs/xfs/xfs_itable.c
+++ b/fs/xfs/xfs_itable.c
@@ -266,121 +266,81 @@ xfs_bulkstat(
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 */
+struct xfs_inumbers_chunk {
+ inumbers_fmt_pf formatter;
+ struct xfs_ibulk *breq;
+};
+
+/*
+ * INUMBERS
+ * ========
+ * This is how we export inode btree records to userspace, so that XFS tools
+ * can figure out where inodes are allocated.
+ */
+
+/*
+ * Format the inode group structure and report it somewhere.
+ *
+ * Similar to xfs_bulkstat_one_int, lastino is the inode cursor as we walk
+ * through the filesystem so we move it forward unless there was a runtime
+ * error. If the formatter tells us the buffer is now full we also move the
+ * cursor forward and abort the walk.
+ */
+STATIC int
+xfs_inumbers_walk(
+ struct xfs_mount *mp,
+ struct xfs_trans *tp,
+ xfs_agnumber_t agno,
+ const struct xfs_inobt_rec_incore *irec,
+ void *data)
{
- if (copy_to_user(ubuffer, buffer, count * sizeof(*buffer)))
- return -EFAULT;
- *written = count * sizeof(*buffer);
- return 0;
+ struct xfs_inogrp inogrp = {
+ .xi_startino = XFS_AGINO_TO_INO(mp, agno, irec->ir_startino),
+ .xi_alloccount = irec->ir_count - irec->ir_freecount,
+ .xi_allocmask = ~irec->ir_free,
+ };
+ struct xfs_inumbers_chunk *ic = data;
+ xfs_agino_t agino;
+ int error;
+
+ error = ic->formatter(ic->breq, &inogrp);
+ if (error && error != XFS_IBULK_ABORT)
+ return error;
+
+ agino = irec->ir_startino + XFS_INODES_PER_CHUNK;
+ ic->breq->startino = XFS_AGINO_TO_INO(mp, agno, agino);
+ return error;
}

/*
* Return inode number table for the filesystem.
*/
-int /* error status */
+int
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 */
+ struct xfs_ibulk *breq,
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;
+ struct xfs_inumbers_chunk ic = {
+ .formatter = formatter,
+ .breq = breq,
+ };
int error = 0;

- *count = 0;
- if (agno >= mp->m_sb.sb_agcount ||
- *lastino != XFS_AGINO_TO_INO(mp, agno, agino))
- return error;
+ if (xfs_bulkstat_already_done(breq->mp, breq->startino))
+ return 0;

- 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);
- }
+ error = xfs_inobt_walk(breq->mp, NULL, breq->startino,
+ xfs_inumbers_walk, breq->icount, &ic);

- kmem_free(buffer);
- if (cur)
- xfs_btree_del_cursor(cur, error);
- if (agbp)
- xfs_buf_relse(agbp);
+ /*
+ * We found some inode groups, 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 inode groups in the buffer.
+ */
+ if (breq->ocount > 0)
+ error = 0;

return error;
}
diff --git a/fs/xfs/xfs_itable.h b/fs/xfs/xfs_itable.h
index 1db1cd30aa29..cfd3c93226f3 100644
--- a/fs/xfs/xfs_itable.h
+++ b/fs/xfs/xfs_itable.h
@@ -43,25 +43,9 @@ typedef int (*bulkstat_one_fmt_pf)(struct xfs_ibulk *breq,
int xfs_bulkstat_one(struct xfs_ibulk *breq, bulkstat_one_fmt_pf formatter);
int xfs_bulkstat(struct xfs_ibulk *breq, bulkstat_one_fmt_pf formatter);

-typedef int (*inumbers_fmt_pf)(
- void __user *ubuffer, /* buffer to write to */
- const xfs_inogrp_t *buffer, /* buffer to read from */
- long count, /* # of elements to read */
- long *written); /* # of bytes written */
+typedef int (*inumbers_fmt_pf)(struct xfs_ibulk *breq,
+ const struct xfs_inogrp *igrp);

-int
-xfs_inumbers_fmt(
- void __user *ubuffer, /* buffer to write to */
- const xfs_inogrp_t *buffer, /* buffer to read from */
- long count, /* # of elements to read */
- long *written); /* # of bytes written */
-
-int /* error status */
-xfs_inumbers(
- xfs_mount_t *mp, /* mount point for filesystem */
- xfs_ino_t *last, /* last inode returned */
- int *count, /* size of buffer/count returned */
- void __user *buffer, /* buffer with inode info */
- inumbers_fmt_pf formatter);
+int xfs_inumbers(struct xfs_ibulk *breq, inumbers_fmt_pf formatter);

#endif /* __XFS_ITABLE_H__ */