summaryrefslogtreecommitdiffstats
path: root/fs/xfs/libxfs/xfs_attr_remote.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/xfs/libxfs/xfs_attr_remote.c')
-rw-r--r--fs/xfs/libxfs/xfs_attr_remote.c638
1 files changed, 638 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_attr_remote.c b/fs/xfs/libxfs/xfs_attr_remote.c
new file mode 100644
index 000000000..d89363c6b
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_attr_remote.c
@@ -0,0 +1,638 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2000-2005 Silicon Graphics, Inc.
+ * Copyright (c) 2013 Red Hat, 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_bit.h"
+#include "xfs_mount.h"
+#include "xfs_defer.h"
+#include "xfs_da_format.h"
+#include "xfs_da_btree.h"
+#include "xfs_inode.h"
+#include "xfs_alloc.h"
+#include "xfs_trans.h"
+#include "xfs_inode_item.h"
+#include "xfs_bmap.h"
+#include "xfs_bmap_util.h"
+#include "xfs_attr.h"
+#include "xfs_attr_leaf.h"
+#include "xfs_attr_remote.h"
+#include "xfs_trans_space.h"
+#include "xfs_trace.h"
+#include "xfs_cksum.h"
+#include "xfs_buf_item.h"
+#include "xfs_error.h"
+
+#define ATTR_RMTVALUE_MAPSIZE 1 /* # of map entries at once */
+
+/*
+ * Each contiguous block has a header, so it is not just a simple attribute
+ * length to FSB conversion.
+ */
+int
+xfs_attr3_rmt_blocks(
+ struct xfs_mount *mp,
+ int attrlen)
+{
+ if (xfs_sb_version_hascrc(&mp->m_sb)) {
+ int buflen = XFS_ATTR3_RMT_BUF_SPACE(mp, mp->m_sb.sb_blocksize);
+ return (attrlen + buflen - 1) / buflen;
+ }
+ return XFS_B_TO_FSB(mp, attrlen);
+}
+
+/*
+ * Checking of the remote attribute header is split into two parts. The verifier
+ * does CRC, location and bounds checking, the unpacking function checks the
+ * attribute parameters and owner.
+ */
+static xfs_failaddr_t
+xfs_attr3_rmt_hdr_ok(
+ void *ptr,
+ xfs_ino_t ino,
+ uint32_t offset,
+ uint32_t size,
+ xfs_daddr_t bno)
+{
+ struct xfs_attr3_rmt_hdr *rmt = ptr;
+
+ if (bno != be64_to_cpu(rmt->rm_blkno))
+ return __this_address;
+ if (offset != be32_to_cpu(rmt->rm_offset))
+ return __this_address;
+ if (size != be32_to_cpu(rmt->rm_bytes))
+ return __this_address;
+ if (ino != be64_to_cpu(rmt->rm_owner))
+ return __this_address;
+
+ /* ok */
+ return NULL;
+}
+
+static xfs_failaddr_t
+xfs_attr3_rmt_verify(
+ struct xfs_mount *mp,
+ void *ptr,
+ int fsbsize,
+ xfs_daddr_t bno)
+{
+ struct xfs_attr3_rmt_hdr *rmt = ptr;
+
+ if (!xfs_sb_version_hascrc(&mp->m_sb))
+ return __this_address;
+ if (rmt->rm_magic != cpu_to_be32(XFS_ATTR3_RMT_MAGIC))
+ return __this_address;
+ if (!uuid_equal(&rmt->rm_uuid, &mp->m_sb.sb_meta_uuid))
+ return __this_address;
+ if (be64_to_cpu(rmt->rm_blkno) != bno)
+ return __this_address;
+ if (be32_to_cpu(rmt->rm_bytes) > fsbsize - sizeof(*rmt))
+ return __this_address;
+ if (be32_to_cpu(rmt->rm_offset) +
+ be32_to_cpu(rmt->rm_bytes) > XFS_XATTR_SIZE_MAX)
+ return __this_address;
+ if (rmt->rm_owner == 0)
+ return __this_address;
+
+ return NULL;
+}
+
+static int
+__xfs_attr3_rmt_read_verify(
+ struct xfs_buf *bp,
+ bool check_crc,
+ xfs_failaddr_t *failaddr)
+{
+ struct xfs_mount *mp = bp->b_target->bt_mount;
+ char *ptr;
+ int len;
+ xfs_daddr_t bno;
+ int blksize = mp->m_attr_geo->blksize;
+
+ /* no verification of non-crc buffers */
+ if (!xfs_sb_version_hascrc(&mp->m_sb))
+ return 0;
+
+ ptr = bp->b_addr;
+ bno = bp->b_bn;
+ len = BBTOB(bp->b_length);
+ ASSERT(len >= blksize);
+
+ while (len > 0) {
+ if (check_crc &&
+ !xfs_verify_cksum(ptr, blksize, XFS_ATTR3_RMT_CRC_OFF)) {
+ *failaddr = __this_address;
+ return -EFSBADCRC;
+ }
+ *failaddr = xfs_attr3_rmt_verify(mp, ptr, blksize, bno);
+ if (*failaddr)
+ return -EFSCORRUPTED;
+ len -= blksize;
+ ptr += blksize;
+ bno += BTOBB(blksize);
+ }
+
+ if (len != 0) {
+ *failaddr = __this_address;
+ return -EFSCORRUPTED;
+ }
+
+ return 0;
+}
+
+static void
+xfs_attr3_rmt_read_verify(
+ struct xfs_buf *bp)
+{
+ xfs_failaddr_t fa;
+ int error;
+
+ error = __xfs_attr3_rmt_read_verify(bp, true, &fa);
+ if (error)
+ xfs_verifier_error(bp, error, fa);
+}
+
+static xfs_failaddr_t
+xfs_attr3_rmt_verify_struct(
+ struct xfs_buf *bp)
+{
+ xfs_failaddr_t fa;
+ int error;
+
+ error = __xfs_attr3_rmt_read_verify(bp, false, &fa);
+ return error ? fa : NULL;
+}
+
+static void
+xfs_attr3_rmt_write_verify(
+ struct xfs_buf *bp)
+{
+ struct xfs_mount *mp = bp->b_target->bt_mount;
+ xfs_failaddr_t fa;
+ int blksize = mp->m_attr_geo->blksize;
+ char *ptr;
+ int len;
+ xfs_daddr_t bno;
+
+ /* no verification of non-crc buffers */
+ if (!xfs_sb_version_hascrc(&mp->m_sb))
+ return;
+
+ ptr = bp->b_addr;
+ bno = bp->b_bn;
+ len = BBTOB(bp->b_length);
+ ASSERT(len >= blksize);
+
+ while (len > 0) {
+ struct xfs_attr3_rmt_hdr *rmt = (struct xfs_attr3_rmt_hdr *)ptr;
+
+ fa = xfs_attr3_rmt_verify(mp, ptr, blksize, bno);
+ if (fa) {
+ xfs_verifier_error(bp, -EFSCORRUPTED, fa);
+ return;
+ }
+
+ /*
+ * Ensure we aren't writing bogus LSNs to disk. See
+ * xfs_attr3_rmt_hdr_set() for the explanation.
+ */
+ if (rmt->rm_lsn != cpu_to_be64(NULLCOMMITLSN)) {
+ xfs_verifier_error(bp, -EFSCORRUPTED, __this_address);
+ return;
+ }
+ xfs_update_cksum(ptr, blksize, XFS_ATTR3_RMT_CRC_OFF);
+
+ len -= blksize;
+ ptr += blksize;
+ bno += BTOBB(blksize);
+ }
+
+ if (len != 0)
+ xfs_verifier_error(bp, -EFSCORRUPTED, __this_address);
+}
+
+const struct xfs_buf_ops xfs_attr3_rmt_buf_ops = {
+ .name = "xfs_attr3_rmt",
+ .verify_read = xfs_attr3_rmt_read_verify,
+ .verify_write = xfs_attr3_rmt_write_verify,
+ .verify_struct = xfs_attr3_rmt_verify_struct,
+};
+
+STATIC int
+xfs_attr3_rmt_hdr_set(
+ struct xfs_mount *mp,
+ void *ptr,
+ xfs_ino_t ino,
+ uint32_t offset,
+ uint32_t size,
+ xfs_daddr_t bno)
+{
+ struct xfs_attr3_rmt_hdr *rmt = ptr;
+
+ if (!xfs_sb_version_hascrc(&mp->m_sb))
+ return 0;
+
+ rmt->rm_magic = cpu_to_be32(XFS_ATTR3_RMT_MAGIC);
+ rmt->rm_offset = cpu_to_be32(offset);
+ rmt->rm_bytes = cpu_to_be32(size);
+ uuid_copy(&rmt->rm_uuid, &mp->m_sb.sb_meta_uuid);
+ rmt->rm_owner = cpu_to_be64(ino);
+ rmt->rm_blkno = cpu_to_be64(bno);
+
+ /*
+ * Remote attribute blocks are written synchronously, so we don't
+ * have an LSN that we can stamp in them that makes any sense to log
+ * recovery. To ensure that log recovery handles overwrites of these
+ * blocks sanely (i.e. once they've been freed and reallocated as some
+ * other type of metadata) we need to ensure that the LSN has a value
+ * that tells log recovery to ignore the LSN and overwrite the buffer
+ * with whatever is in it's log. To do this, we use the magic
+ * NULLCOMMITLSN to indicate that the LSN is invalid.
+ */
+ rmt->rm_lsn = cpu_to_be64(NULLCOMMITLSN);
+
+ return sizeof(struct xfs_attr3_rmt_hdr);
+}
+
+/*
+ * Helper functions to copy attribute data in and out of the one disk extents
+ */
+STATIC int
+xfs_attr_rmtval_copyout(
+ struct xfs_mount *mp,
+ struct xfs_buf *bp,
+ xfs_ino_t ino,
+ int *offset,
+ int *valuelen,
+ uint8_t **dst)
+{
+ char *src = bp->b_addr;
+ xfs_daddr_t bno = bp->b_bn;
+ int len = BBTOB(bp->b_length);
+ int blksize = mp->m_attr_geo->blksize;
+
+ ASSERT(len >= blksize);
+
+ while (len > 0 && *valuelen > 0) {
+ int hdr_size = 0;
+ int byte_cnt = XFS_ATTR3_RMT_BUF_SPACE(mp, blksize);
+
+ byte_cnt = min(*valuelen, byte_cnt);
+
+ if (xfs_sb_version_hascrc(&mp->m_sb)) {
+ if (xfs_attr3_rmt_hdr_ok(src, ino, *offset,
+ byte_cnt, bno)) {
+ xfs_alert(mp,
+"remote attribute header mismatch bno/off/len/owner (0x%llx/0x%x/Ox%x/0x%llx)",
+ bno, *offset, byte_cnt, ino);
+ return -EFSCORRUPTED;
+ }
+ hdr_size = sizeof(struct xfs_attr3_rmt_hdr);
+ }
+
+ memcpy(*dst, src + hdr_size, byte_cnt);
+
+ /* roll buffer forwards */
+ len -= blksize;
+ src += blksize;
+ bno += BTOBB(blksize);
+
+ /* roll attribute data forwards */
+ *valuelen -= byte_cnt;
+ *dst += byte_cnt;
+ *offset += byte_cnt;
+ }
+ return 0;
+}
+
+STATIC void
+xfs_attr_rmtval_copyin(
+ struct xfs_mount *mp,
+ struct xfs_buf *bp,
+ xfs_ino_t ino,
+ int *offset,
+ int *valuelen,
+ uint8_t **src)
+{
+ char *dst = bp->b_addr;
+ xfs_daddr_t bno = bp->b_bn;
+ int len = BBTOB(bp->b_length);
+ int blksize = mp->m_attr_geo->blksize;
+
+ ASSERT(len >= blksize);
+
+ while (len > 0 && *valuelen > 0) {
+ int hdr_size;
+ int byte_cnt = XFS_ATTR3_RMT_BUF_SPACE(mp, blksize);
+
+ byte_cnt = min(*valuelen, byte_cnt);
+ hdr_size = xfs_attr3_rmt_hdr_set(mp, dst, ino, *offset,
+ byte_cnt, bno);
+
+ memcpy(dst + hdr_size, *src, byte_cnt);
+
+ /*
+ * If this is the last block, zero the remainder of it.
+ * Check that we are actually the last block, too.
+ */
+ if (byte_cnt + hdr_size < blksize) {
+ ASSERT(*valuelen - byte_cnt == 0);
+ ASSERT(len == blksize);
+ memset(dst + hdr_size + byte_cnt, 0,
+ blksize - hdr_size - byte_cnt);
+ }
+
+ /* roll buffer forwards */
+ len -= blksize;
+ dst += blksize;
+ bno += BTOBB(blksize);
+
+ /* roll attribute data forwards */
+ *valuelen -= byte_cnt;
+ *src += byte_cnt;
+ *offset += byte_cnt;
+ }
+}
+
+/*
+ * Read the value associated with an attribute from the out-of-line buffer
+ * that we stored it in.
+ */
+int
+xfs_attr_rmtval_get(
+ struct xfs_da_args *args)
+{
+ struct xfs_bmbt_irec map[ATTR_RMTVALUE_MAPSIZE];
+ struct xfs_mount *mp = args->dp->i_mount;
+ struct xfs_buf *bp;
+ xfs_dablk_t lblkno = args->rmtblkno;
+ uint8_t *dst = args->value;
+ int valuelen;
+ int nmap;
+ int error;
+ int blkcnt = args->rmtblkcnt;
+ int i;
+ int offset = 0;
+
+ trace_xfs_attr_rmtval_get(args);
+
+ ASSERT(!(args->flags & ATTR_KERNOVAL));
+ ASSERT(args->rmtvaluelen == args->valuelen);
+
+ valuelen = args->rmtvaluelen;
+ while (valuelen > 0) {
+ nmap = ATTR_RMTVALUE_MAPSIZE;
+ error = xfs_bmapi_read(args->dp, (xfs_fileoff_t)lblkno,
+ blkcnt, map, &nmap,
+ XFS_BMAPI_ATTRFORK);
+ if (error)
+ return error;
+ ASSERT(nmap >= 1);
+
+ for (i = 0; (i < nmap) && (valuelen > 0); i++) {
+ xfs_daddr_t dblkno;
+ int dblkcnt;
+
+ ASSERT((map[i].br_startblock != DELAYSTARTBLOCK) &&
+ (map[i].br_startblock != HOLESTARTBLOCK));
+ dblkno = XFS_FSB_TO_DADDR(mp, map[i].br_startblock);
+ dblkcnt = XFS_FSB_TO_BB(mp, map[i].br_blockcount);
+ error = xfs_trans_read_buf(mp, args->trans,
+ mp->m_ddev_targp,
+ dblkno, dblkcnt, 0, &bp,
+ &xfs_attr3_rmt_buf_ops);
+ if (error)
+ return error;
+
+ error = xfs_attr_rmtval_copyout(mp, bp, args->dp->i_ino,
+ &offset, &valuelen,
+ &dst);
+ xfs_trans_brelse(args->trans, bp);
+ if (error)
+ return error;
+
+ /* roll attribute extent map forwards */
+ lblkno += map[i].br_blockcount;
+ blkcnt -= map[i].br_blockcount;
+ }
+ }
+ ASSERT(valuelen == 0);
+ return 0;
+}
+
+/*
+ * Write the value associated with an attribute into the out-of-line buffer
+ * that we have defined for it.
+ */
+int
+xfs_attr_rmtval_set(
+ struct xfs_da_args *args)
+{
+ struct xfs_inode *dp = args->dp;
+ struct xfs_mount *mp = dp->i_mount;
+ struct xfs_bmbt_irec map;
+ xfs_dablk_t lblkno;
+ xfs_fileoff_t lfileoff = 0;
+ uint8_t *src = args->value;
+ int blkcnt;
+ int valuelen;
+ int nmap;
+ int error;
+ int offset = 0;
+
+ trace_xfs_attr_rmtval_set(args);
+
+ /*
+ * Find a "hole" in the attribute address space large enough for
+ * us to drop the new attribute's value into. Because CRC enable
+ * attributes have headers, we can't just do a straight byte to FSB
+ * conversion and have to take the header space into account.
+ */
+ blkcnt = xfs_attr3_rmt_blocks(mp, args->rmtvaluelen);
+ error = xfs_bmap_first_unused(args->trans, args->dp, blkcnt, &lfileoff,
+ XFS_ATTR_FORK);
+ if (error)
+ return error;
+
+ args->rmtblkno = lblkno = (xfs_dablk_t)lfileoff;
+ args->rmtblkcnt = blkcnt;
+
+ /*
+ * Roll through the "value", allocating blocks on disk as required.
+ */
+ while (blkcnt > 0) {
+ /*
+ * Allocate a single extent, up to the size of the value.
+ *
+ * Note that we have to consider this a data allocation as we
+ * write the remote attribute without logging the contents.
+ * Hence we must ensure that we aren't using blocks that are on
+ * the busy list so that we don't overwrite blocks which have
+ * recently been freed but their transactions are not yet
+ * committed to disk. If we overwrite the contents of a busy
+ * extent and then crash then the block may not contain the
+ * correct metadata after log recovery occurs.
+ */
+ nmap = 1;
+ error = xfs_bmapi_write(args->trans, dp, (xfs_fileoff_t)lblkno,
+ blkcnt, XFS_BMAPI_ATTRFORK, args->total, &map,
+ &nmap);
+ if (error)
+ return error;
+ error = xfs_defer_finish(&args->trans);
+ if (error)
+ return error;
+
+ ASSERT(nmap == 1);
+ ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
+ (map.br_startblock != HOLESTARTBLOCK));
+ lblkno += map.br_blockcount;
+ blkcnt -= map.br_blockcount;
+
+ /*
+ * Start the next trans in the chain.
+ */
+ error = xfs_trans_roll_inode(&args->trans, dp);
+ if (error)
+ return error;
+ }
+
+ /*
+ * Roll through the "value", copying the attribute value to the
+ * already-allocated blocks. Blocks are written synchronously
+ * so that we can know they are all on disk before we turn off
+ * the INCOMPLETE flag.
+ */
+ lblkno = args->rmtblkno;
+ blkcnt = args->rmtblkcnt;
+ valuelen = args->rmtvaluelen;
+ while (valuelen > 0) {
+ struct xfs_buf *bp;
+ xfs_daddr_t dblkno;
+ int dblkcnt;
+
+ ASSERT(blkcnt > 0);
+
+ nmap = 1;
+ error = xfs_bmapi_read(dp, (xfs_fileoff_t)lblkno,
+ blkcnt, &map, &nmap,
+ XFS_BMAPI_ATTRFORK);
+ if (error)
+ return error;
+ ASSERT(nmap == 1);
+ ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
+ (map.br_startblock != HOLESTARTBLOCK));
+
+ dblkno = XFS_FSB_TO_DADDR(mp, map.br_startblock),
+ dblkcnt = XFS_FSB_TO_BB(mp, map.br_blockcount);
+
+ bp = xfs_buf_get(mp->m_ddev_targp, dblkno, dblkcnt, 0);
+ if (!bp)
+ return -ENOMEM;
+ bp->b_ops = &xfs_attr3_rmt_buf_ops;
+
+ xfs_attr_rmtval_copyin(mp, bp, args->dp->i_ino, &offset,
+ &valuelen, &src);
+
+ error = xfs_bwrite(bp); /* GROT: NOTE: synchronous write */
+ xfs_buf_relse(bp);
+ if (error)
+ return error;
+
+
+ /* roll attribute extent map forwards */
+ lblkno += map.br_blockcount;
+ blkcnt -= map.br_blockcount;
+ }
+ ASSERT(valuelen == 0);
+ return 0;
+}
+
+/*
+ * Remove the value associated with an attribute by deleting the
+ * out-of-line buffer that it is stored on.
+ */
+int
+xfs_attr_rmtval_remove(
+ struct xfs_da_args *args)
+{
+ struct xfs_mount *mp = args->dp->i_mount;
+ xfs_dablk_t lblkno;
+ int blkcnt;
+ int error;
+ int done;
+
+ trace_xfs_attr_rmtval_remove(args);
+
+ /*
+ * Roll through the "value", invalidating the attribute value's blocks.
+ */
+ lblkno = args->rmtblkno;
+ blkcnt = args->rmtblkcnt;
+ while (blkcnt > 0) {
+ struct xfs_bmbt_irec map;
+ struct xfs_buf *bp;
+ xfs_daddr_t dblkno;
+ int dblkcnt;
+ int nmap;
+
+ /*
+ * Try to remember where we decided to put the value.
+ */
+ nmap = 1;
+ error = xfs_bmapi_read(args->dp, (xfs_fileoff_t)lblkno,
+ blkcnt, &map, &nmap, XFS_BMAPI_ATTRFORK);
+ if (error)
+ return error;
+ ASSERT(nmap == 1);
+ ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
+ (map.br_startblock != HOLESTARTBLOCK));
+
+ dblkno = XFS_FSB_TO_DADDR(mp, map.br_startblock),
+ dblkcnt = XFS_FSB_TO_BB(mp, map.br_blockcount);
+
+ /*
+ * If the "remote" value is in the cache, remove it.
+ */
+ bp = xfs_buf_incore(mp->m_ddev_targp, dblkno, dblkcnt, XBF_TRYLOCK);
+ if (bp) {
+ xfs_buf_stale(bp);
+ xfs_buf_relse(bp);
+ bp = NULL;
+ }
+
+ lblkno += map.br_blockcount;
+ blkcnt -= map.br_blockcount;
+ }
+
+ /*
+ * Keep de-allocating extents until the remote-value region is gone.
+ */
+ lblkno = args->rmtblkno;
+ blkcnt = args->rmtblkcnt;
+ done = 0;
+ while (!done) {
+ error = xfs_bunmapi(args->trans, args->dp, lblkno, blkcnt,
+ XFS_BMAPI_ATTRFORK, 1, &done);
+ if (error)
+ return error;
+ error = xfs_defer_finish(&args->trans);
+ if (error)
+ return error;
+
+ /*
+ * Close out trans and start the next one in the chain.
+ */
+ error = xfs_trans_roll_inode(&args->trans, args->dp);
+ if (error)
+ return error;
+ }
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-28 08:29:44 +0000