* Else, *lastxp will be set to the index of the found
* entry; *gotp will contain the entry.
*/
-STATIC xfs_bmbt_rec_host_t * /* pointer to found extent entry */
+xfs_bmbt_rec_host_t * /* pointer to found extent entry */
xfs_bmap_search_extents(
xfs_inode_t *ip, /* incore inode pointer */
xfs_fileoff_t bno, /* block number searched for */
return 0;
}
-STATIC int
+int
xfs_bmapi_reserve_delalloc(
struct xfs_inode *ip,
xfs_fileoff_t aoff,
return error;
}
-/*
- * Map file blocks to filesystem blocks, adding delayed allocations as needed.
- */
-int
-xfs_bmapi_delay(
- struct xfs_inode *ip, /* incore inode */
- xfs_fileoff_t bno, /* starting file offs. mapped */
- xfs_filblks_t len, /* length to map in file */
- struct xfs_bmbt_irec *mval, /* output: map values */
- int *nmap, /* i/o: mval size/count */
- int flags) /* XFS_BMAPI_... */
-{
- struct xfs_mount *mp = ip->i_mount;
- struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
- struct xfs_bmbt_irec got; /* current file extent record */
- struct xfs_bmbt_irec prev; /* previous file extent record */
- xfs_fileoff_t obno; /* old block number (offset) */
- xfs_fileoff_t end; /* end of mapped file region */
- xfs_extnum_t lastx; /* last useful extent number */
- int eof; /* we've hit the end of extents */
- int n = 0; /* current extent index */
- int error = 0;
-
- ASSERT(*nmap >= 1);
- ASSERT(*nmap <= XFS_BMAP_MAX_NMAP);
- ASSERT(!(flags & ~XFS_BMAPI_ENTIRE));
- ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
-
- if (unlikely(XFS_TEST_ERROR(
- (XFS_IFORK_FORMAT(ip, XFS_DATA_FORK) != XFS_DINODE_FMT_EXTENTS &&
- XFS_IFORK_FORMAT(ip, XFS_DATA_FORK) != XFS_DINODE_FMT_BTREE),
- mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
- XFS_ERROR_REPORT("xfs_bmapi_delay", XFS_ERRLEVEL_LOW, mp);
- return -EFSCORRUPTED;
- }
-
- if (XFS_FORCED_SHUTDOWN(mp))
- return -EIO;
-
- XFS_STATS_INC(mp, xs_blk_mapw);
-
- if (!(ifp->if_flags & XFS_IFEXTENTS)) {
- error = xfs_iread_extents(NULL, ip, XFS_DATA_FORK);
- if (error)
- return error;
- }
-
- xfs_bmap_search_extents(ip, bno, XFS_DATA_FORK, &eof, &lastx, &got, &prev);
- end = bno + len;
- obno = bno;
-
- while (bno < end && n < *nmap) {
- if (eof || got.br_startoff > bno) {
- error = xfs_bmapi_reserve_delalloc(ip, bno, len, &got,
- &prev, &lastx, eof);
- if (error) {
- if (n == 0) {
- *nmap = 0;
- return error;
- }
- break;
- }
- }
-
- /* set up the extent map to return. */
- xfs_bmapi_trim_map(mval, &got, &bno, len, obno, end, n, flags);
- xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags);
-
- /* If we're done, stop now. */
- if (bno >= end || n >= *nmap)
- break;
-
- /* Else go on to the next record. */
- prev = got;
- if (++lastx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t))
- xfs_bmbt_get_all(xfs_iext_get_ext(ifp, lastx), &got);
- else
- eof = 1;
- }
-
- *nmap = n;
- return 0;
-}
-
-
static int
xfs_bmapi_allocate(
struct xfs_bmalloca *bma)
/*
* Copyright (c) 2000-2006 Silicon Graphics, Inc.
+ * Copyright (c) 2016 Christoph Hellwig.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
#define XFS_WRITEIO_ALIGN(mp,off) (((off) >> mp->m_writeio_log) \
<< mp->m_writeio_log)
-#define XFS_WRITE_IMAPS XFS_BMAP_MAX_NMAP
void
xfs_bmbt_to_iomap(
goto out_unlock;
}
-/*
- * If the caller is doing a write at the end of the file, then extend the
- * allocation out to the file system's write iosize. We clean up any extra
- * space left over when the file is closed in xfs_inactive().
- *
- * If we find we already have delalloc preallocation beyond EOF, don't do more
- * preallocation as it it not needed.
- */
-STATIC int
-xfs_iomap_eof_want_preallocate(
- xfs_mount_t *mp,
- xfs_inode_t *ip,
- xfs_off_t offset,
- size_t count,
- xfs_bmbt_irec_t *imap,
- int nimaps,
- int *prealloc)
-{
- xfs_fileoff_t start_fsb;
- xfs_filblks_t count_fsb;
- int n, error, imaps;
- int found_delalloc = 0;
-
- *prealloc = 0;
- if (offset + count <= XFS_ISIZE(ip))
- return 0;
-
- /*
- * If the file is smaller than the minimum prealloc and we are using
- * dynamic preallocation, don't do any preallocation at all as it is
- * likely this is the only write to the file that is going to be done.
- */
- if (!(mp->m_flags & XFS_MOUNT_DFLT_IOSIZE) &&
- XFS_ISIZE(ip) < XFS_FSB_TO_B(mp, mp->m_writeio_blocks))
- return 0;
-
- /*
- * If there are any real blocks past eof, then don't
- * do any speculative allocation.
- */
- start_fsb = XFS_B_TO_FSBT(mp, ((xfs_ufsize_t)(offset + count - 1)));
- count_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
- while (count_fsb > 0) {
- imaps = nimaps;
- error = xfs_bmapi_read(ip, start_fsb, count_fsb, imap, &imaps,
- 0);
- if (error)
- return error;
- for (n = 0; n < imaps; n++) {
- if ((imap[n].br_startblock != HOLESTARTBLOCK) &&
- (imap[n].br_startblock != DELAYSTARTBLOCK))
- return 0;
- start_fsb += imap[n].br_blockcount;
- count_fsb -= imap[n].br_blockcount;
-
- if (imap[n].br_startblock == DELAYSTARTBLOCK)
- found_delalloc = 1;
- }
- }
- if (!found_delalloc)
- *prealloc = 1;
- return 0;
-}
-
-/*
- * Determine the initial size of the preallocation. We are beyond the current
- * EOF here, but we need to take into account whether this is a sparse write or
- * an extending write when determining the preallocation size. Hence we need to
- * look up the extent that ends at the current write offset and use the result
- * to determine the preallocation size.
- *
- * If the extent is a hole, then preallocation is essentially disabled.
- * Otherwise we take the size of the preceeding data extent as the basis for the
- * preallocation size. If the size of the extent is greater than half the
- * maximum extent length, then use the current offset as the basis. This ensures
- * that for large files the preallocation size always extends to MAXEXTLEN
- * rather than falling short due to things like stripe unit/width alignment of
- * real extents.
- */
-STATIC xfs_fsblock_t
-xfs_iomap_eof_prealloc_initial_size(
- struct xfs_mount *mp,
- struct xfs_inode *ip,
- xfs_off_t offset,
- xfs_bmbt_irec_t *imap,
- int nimaps)
-{
- xfs_fileoff_t start_fsb;
- int imaps = 1;
- int error;
-
- ASSERT(nimaps >= imaps);
-
- /* if we are using a specific prealloc size, return now */
- if (mp->m_flags & XFS_MOUNT_DFLT_IOSIZE)
- return 0;
-
- /* If the file is small, then use the minimum prealloc */
- if (XFS_ISIZE(ip) < XFS_FSB_TO_B(mp, mp->m_dalign))
- return 0;
-
- /*
- * As we write multiple pages, the offset will always align to the
- * start of a page and hence point to a hole at EOF. i.e. if the size is
- * 4096 bytes, we only have one block at FSB 0, but XFS_B_TO_FSB(4096)
- * will return FSB 1. Hence if there are blocks in the file, we want to
- * point to the block prior to the EOF block and not the hole that maps
- * directly at @offset.
- */
- start_fsb = XFS_B_TO_FSB(mp, offset);
- if (start_fsb)
- start_fsb--;
- error = xfs_bmapi_read(ip, start_fsb, 1, imap, &imaps, XFS_BMAPI_ENTIRE);
- if (error)
- return 0;
-
- ASSERT(imaps == 1);
- if (imap[0].br_startblock == HOLESTARTBLOCK)
- return 0;
- if (imap[0].br_blockcount <= (MAXEXTLEN >> 1))
- return imap[0].br_blockcount << 1;
- return XFS_B_TO_FSB(mp, offset);
-}
-
STATIC bool
xfs_quota_need_throttle(
struct xfs_inode *ip,
}
/*
+ * If we are doing a write at the end of the file and there are no allocations
+ * past this one, then extend the allocation out to the file system's write
+ * iosize.
+ *
* If we don't have a user specified preallocation size, dynamically increase
- * the preallocation size as the size of the file grows. Cap the maximum size
+ * the preallocation size as the size of the file grows. Cap the maximum size
* at a single extent or less if the filesystem is near full. The closer the
* filesystem is to full, the smaller the maximum prealocation.
+ *
+ * As an exception we don't do any preallocation at all if the file is smaller
+ * than the minimum preallocation and we are using the default dynamic
+ * preallocation scheme, as it is likely this is the only write to the file that
+ * is going to be done.
+ *
+ * We clean up any extra space left over when the file is closed in
+ * xfs_inactive().
*/
STATIC xfs_fsblock_t
xfs_iomap_prealloc_size(
- struct xfs_mount *mp,
struct xfs_inode *ip,
- xfs_off_t offset,
- struct xfs_bmbt_irec *imap,
- int nimaps)
+ loff_t offset,
+ loff_t count,
+ xfs_extnum_t idx,
+ struct xfs_bmbt_irec *prev)
{
- xfs_fsblock_t alloc_blocks = 0;
+ struct xfs_mount *mp = ip->i_mount;
+ xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset);
int shift = 0;
int64_t freesp;
xfs_fsblock_t qblocks;
int qshift = 0;
+ xfs_fsblock_t alloc_blocks = 0;
+
+ if (offset + count <= XFS_ISIZE(ip))
+ return 0;
+
+ if (!(mp->m_flags & XFS_MOUNT_DFLT_IOSIZE) &&
+ (XFS_ISIZE(ip) < XFS_FSB_TO_B(mp, mp->m_writeio_blocks)))
+ return 0;
- alloc_blocks = xfs_iomap_eof_prealloc_initial_size(mp, ip, offset,
- imap, nimaps);
+ /*
+ * If an explicit allocsize is set, the file is small, or we
+ * are writing behind a hole, then use the minimum prealloc:
+ */
+ if ((mp->m_flags & XFS_MOUNT_DFLT_IOSIZE) ||
+ XFS_ISIZE(ip) < XFS_FSB_TO_B(mp, mp->m_dalign) ||
+ idx == 0 ||
+ prev->br_startoff + prev->br_blockcount < offset_fsb)
+ return mp->m_writeio_blocks;
+
+ /*
+ * Determine the initial size of the preallocation. We are beyond the
+ * current EOF here, but we need to take into account whether this is
+ * a sparse write or an extending write when determining the
+ * preallocation size. Hence we need to look up the extent that ends
+ * at the current write offset and use the result to determine the
+ * preallocation size.
+ *
+ * If the extent is a hole, then preallocation is essentially disabled.
+ * Otherwise we take the size of the preceding data extent as the basis
+ * for the preallocation size. If the size of the extent is greater than
+ * half the maximum extent length, then use the current offset as the
+ * basis. This ensures that for large files the preallocation size
+ * always extends to MAXEXTLEN rather than falling short due to things
+ * like stripe unit/width alignment of real extents.
+ */
+ if (prev->br_blockcount <= (MAXEXTLEN >> 1))
+ alloc_blocks = prev->br_blockcount << 1;
+ else
+ alloc_blocks = XFS_B_TO_FSB(mp, offset);
if (!alloc_blocks)
goto check_writeio;
qblocks = alloc_blocks;
*/
while (alloc_blocks && alloc_blocks >= freesp)
alloc_blocks >>= 4;
-
check_writeio:
if (alloc_blocks < mp->m_writeio_blocks)
alloc_blocks = mp->m_writeio_blocks;
-
trace_xfs_iomap_prealloc_size(ip, alloc_blocks, shift,
mp->m_writeio_blocks);
-
return alloc_blocks;
}
-int
-xfs_iomap_write_delay(
- xfs_inode_t *ip,
- xfs_off_t offset,
- size_t count,
- xfs_bmbt_irec_t *ret_imap)
+static int
+xfs_file_iomap_begin_delay(
+ struct inode *inode,
+ loff_t offset,
+ loff_t count,
+ unsigned flags,
+ struct iomap *iomap)
{
- xfs_mount_t *mp = ip->i_mount;
- xfs_fileoff_t offset_fsb;
- xfs_fileoff_t last_fsb;
- xfs_off_t aligned_offset;
- xfs_fileoff_t ioalign;
- xfs_extlen_t extsz;
- int nimaps;
- xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS];
- int prealloc;
- int error;
-
- ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
-
- /*
- * Make sure that the dquots are there. This doesn't hold
- * the ilock across a disk read.
- */
- error = xfs_qm_dqattach_locked(ip, 0);
- if (error)
- return error;
+ struct xfs_inode *ip = XFS_I(inode);
+ struct xfs_mount *mp = ip->i_mount;
+ struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
+ xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset);
+ xfs_fileoff_t maxbytes_fsb =
+ XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
+ xfs_fileoff_t end_fsb, orig_end_fsb;
+ int error = 0, eof = 0;
+ struct xfs_bmbt_irec got;
+ struct xfs_bmbt_irec prev;
+ xfs_extnum_t idx;
- extsz = xfs_get_extsz_hint(ip);
- offset_fsb = XFS_B_TO_FSBT(mp, offset);
+ ASSERT(!XFS_IS_REALTIME_INODE(ip));
+ ASSERT(!xfs_get_extsz_hint(ip));
- error = xfs_iomap_eof_want_preallocate(mp, ip, offset, count,
- imap, XFS_WRITE_IMAPS, &prealloc);
- if (error)
- return error;
+ xfs_ilock(ip, XFS_ILOCK_EXCL);
-retry:
- if (prealloc) {
- xfs_fsblock_t alloc_blocks;
+ if (unlikely(XFS_TEST_ERROR(
+ (XFS_IFORK_FORMAT(ip, XFS_DATA_FORK) != XFS_DINODE_FMT_EXTENTS &&
+ XFS_IFORK_FORMAT(ip, XFS_DATA_FORK) != XFS_DINODE_FMT_BTREE),
+ mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
+ XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
+ error = -EFSCORRUPTED;
+ goto out_unlock;
+ }
- alloc_blocks = xfs_iomap_prealloc_size(mp, ip, offset, imap,
- XFS_WRITE_IMAPS);
+ XFS_STATS_INC(mp, xs_blk_mapw);
- aligned_offset = XFS_WRITEIO_ALIGN(mp, (offset + count - 1));
- ioalign = XFS_B_TO_FSBT(mp, aligned_offset);
- last_fsb = ioalign + alloc_blocks;
- } else {
- last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
+ if (!(ifp->if_flags & XFS_IFEXTENTS)) {
+ error = xfs_iread_extents(NULL, ip, XFS_DATA_FORK);
+ if (error)
+ goto out_unlock;
}
- if (prealloc || extsz) {
- error = xfs_iomap_eof_align_last_fsb(ip, extsz, &last_fsb);
- if (error)
- return error;
+ xfs_bmap_search_extents(ip, offset_fsb, XFS_DATA_FORK, &eof, &idx,
+ &got, &prev);
+ if (!eof && got.br_startoff <= offset_fsb) {
+ trace_xfs_iomap_found(ip, offset, count, 0, &got);
+ goto done;
}
+ error = xfs_qm_dqattach_locked(ip, 0);
+ if (error)
+ goto out_unlock;
+
/*
- * Make sure preallocation does not create extents beyond the range we
- * actually support in this filesystem.
+ * We cap the maximum length we map here to MAX_WRITEBACK_PAGES pages
+ * to keep the chunks of work done where somewhat symmetric with the
+ * work writeback does. This is a completely arbitrary number pulled
+ * out of thin air as a best guess for initial testing.
+ *
+ * Note that the values needs to be less than 32-bits wide until
+ * the lower level functions are updated.
*/
- if (last_fsb > XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes))
- last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
+ count = min_t(loff_t, count, 1024 * PAGE_SIZE);
+ end_fsb = orig_end_fsb =
+ min(XFS_B_TO_FSB(mp, offset + count), maxbytes_fsb);
- ASSERT(last_fsb > offset_fsb);
+ if (eof) {
+ xfs_fsblock_t prealloc_blocks;
- nimaps = XFS_WRITE_IMAPS;
- error = xfs_bmapi_delay(ip, offset_fsb, last_fsb - offset_fsb,
- imap, &nimaps, XFS_BMAPI_ENTIRE);
+ prealloc_blocks =
+ xfs_iomap_prealloc_size(ip, offset, count, idx, &prev);
+ if (prealloc_blocks) {
+ xfs_extlen_t align;
+ xfs_off_t end_offset;
+
+ end_offset = XFS_WRITEIO_ALIGN(mp, offset + count - 1);
+ end_fsb = XFS_B_TO_FSBT(mp, end_offset) +
+ prealloc_blocks;
+
+ align = xfs_eof_alignment(ip, 0);
+ if (align)
+ end_fsb = roundup_64(end_fsb, align);
+
+ end_fsb = min(end_fsb, maxbytes_fsb);
+ ASSERT(end_fsb > offset_fsb);
+ }
+ }
+
+retry:
+ error = xfs_bmapi_reserve_delalloc(ip, offset_fsb,
+ end_fsb - offset_fsb, &got,
+ &prev, &idx, eof);
switch (error) {
case 0:
+ break;
case -ENOSPC:
case -EDQUOT:
- break;
- default:
- return error;
- }
-
- /*
- * If bmapi returned us nothing, we got either ENOSPC or EDQUOT. Retry
- * without EOF preallocation.
- */
- if (nimaps == 0) {
+ /* retry without any preallocation */
trace_xfs_delalloc_enospc(ip, offset, count);
- if (prealloc) {
- prealloc = 0;
- error = 0;
+ if (end_fsb != orig_end_fsb) {
+ end_fsb = orig_end_fsb;
goto retry;
}
- return error ? error : -ENOSPC;
+ /*FALLTHRU*/
+ default:
+ goto out_unlock;
}
- if (!(imap[0].br_startblock || XFS_IS_REALTIME_INODE(ip)))
- return xfs_alert_fsblock_zero(ip, &imap[0]);
-
/*
* Tag the inode as speculatively preallocated so we can reclaim this
* space on demand, if necessary.
*/
- if (prealloc)
+ if (end_fsb != orig_end_fsb)
xfs_inode_set_eofblocks_tag(ip);
- *ret_imap = imap[0];
- return 0;
+ trace_xfs_iomap_alloc(ip, offset, count, 0, &got);
+done:
+ if (isnullstartblock(got.br_startblock))
+ got.br_startblock = DELAYSTARTBLOCK;
+
+ if (!got.br_startblock) {
+ error = xfs_alert_fsblock_zero(ip, &got);
+ if (error)
+ goto out_unlock;
+ }
+
+ xfs_bmbt_to_iomap(ip, iomap, &got);
+
+out_unlock:
+ xfs_iunlock(ip, XFS_ILOCK_EXCL);
+ return error;
}
/*
if (XFS_FORCED_SHUTDOWN(mp))
return -EIO;
+ if ((flags & IOMAP_WRITE) && !xfs_get_extsz_hint(ip)) {
+ return xfs_file_iomap_begin_delay(inode, offset, length, flags,
+ iomap);
+ }
+
xfs_ilock(ip, XFS_ILOCK_EXCL);
ASSERT(offset <= mp->m_super->s_maxbytes);
* the lower level functions are updated.
*/
length = min_t(loff_t, length, 1024 * PAGE_SIZE);
- if (xfs_get_extsz_hint(ip)) {
- /*
- * xfs_iomap_write_direct() expects the shared lock. It
- * is unlocked on return.
- */
- xfs_ilock_demote(ip, XFS_ILOCK_EXCL);
- error = xfs_iomap_write_direct(ip, offset, length, &imap,
- nimaps);
- } else {
- error = xfs_iomap_write_delay(ip, offset, length, &imap);
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
- }
-
+ /*
+ * xfs_iomap_write_direct() expects the shared lock. It
+ * is unlocked on return.
+ */
+ xfs_ilock_demote(ip, XFS_ILOCK_EXCL);
+ error = xfs_iomap_write_direct(ip, offset, length, &imap,
+ nimaps);
if (error)
return error;