diff options
Diffstat (limited to 'fs/xfs/xfs_bmap_util.c')
| -rw-r--r-- | fs/xfs/xfs_bmap_util.c | 861 |
1 files changed, 861 insertions, 0 deletions
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 8e48ddf1c11c..f557022bd0e7 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -1,5 +1,6 @@ /* * Copyright (c) 2000-2006 Silicon Graphics, Inc. + * Copyright (c) 2012 Red Hat, Inc. * All Rights Reserved. * * This program is free software; you can redistribute it and/or @@ -41,6 +42,7 @@ #include "xfs_quota.h" #include "xfs_trans_space.h" #include "xfs_trace.h" +#include "xfs_icache.h" /* Kernel only BMAP related definitions and functions */ @@ -832,3 +834,862 @@ next_block: return error; } + +/* + * Test whether it is appropriate to check an inode for and free post EOF + * blocks. The 'force' parameter determines whether we should also consider + * regular files that are marked preallocated or append-only. + */ +bool +xfs_can_free_eofblocks(struct xfs_inode *ip, bool force) +{ + /* prealloc/delalloc exists only on regular files */ + if (!S_ISREG(ip->i_d.di_mode)) + return false; + + /* + * Zero sized files with no cached pages and delalloc blocks will not + * have speculative prealloc/delalloc blocks to remove. + */ + if (VFS_I(ip)->i_size == 0 && + VN_CACHED(VFS_I(ip)) == 0 && + ip->i_delayed_blks == 0) + return false; + + /* If we haven't read in the extent list, then don't do it now. */ + if (!(ip->i_df.if_flags & XFS_IFEXTENTS)) + return false; + + /* + * Do not free real preallocated or append-only files unless the file + * has delalloc blocks and we are forced to remove them. + */ + if (ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)) + if (!force || ip->i_delayed_blks == 0) + return false; + + return true; +} + +/* + * This is called by xfs_inactive to free any blocks beyond eof + * when the link count isn't zero and by xfs_dm_punch_hole() when + * punching a hole to EOF. + */ +int +xfs_free_eofblocks( + xfs_mount_t *mp, + xfs_inode_t *ip, + bool need_iolock) +{ + xfs_trans_t *tp; + int error; + xfs_fileoff_t end_fsb; + xfs_fileoff_t last_fsb; + xfs_filblks_t map_len; + int nimaps; + xfs_bmbt_irec_t imap; + + /* + * Figure out if there are any blocks beyond the end + * of the file. If not, then there is nothing to do. + */ + end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip)); + last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes); + if (last_fsb <= end_fsb) + return 0; + map_len = last_fsb - end_fsb; + + nimaps = 1; + xfs_ilock(ip, XFS_ILOCK_SHARED); + error = xfs_bmapi_read(ip, end_fsb, map_len, &imap, &nimaps, 0); + xfs_iunlock(ip, XFS_ILOCK_SHARED); + + if (!error && (nimaps != 0) && + (imap.br_startblock != HOLESTARTBLOCK || + ip->i_delayed_blks)) { + /* + * Attach the dquots to the inode up front. + */ + error = xfs_qm_dqattach(ip, 0); + if (error) + return error; + + /* + * There are blocks after the end of file. + * Free them up now by truncating the file to + * its current size. + */ + tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE); + + if (need_iolock) { + if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) { + xfs_trans_cancel(tp, 0); + return EAGAIN; + } + } + + error = xfs_trans_reserve(tp, 0, + XFS_ITRUNCATE_LOG_RES(mp), + 0, XFS_TRANS_PERM_LOG_RES, + XFS_ITRUNCATE_LOG_COUNT); + if (error) { + ASSERT(XFS_FORCED_SHUTDOWN(mp)); + xfs_trans_cancel(tp, 0); + if (need_iolock) + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + return error; + } + + xfs_ilock(ip, XFS_ILOCK_EXCL); + xfs_trans_ijoin(tp, ip, 0); + + /* + * Do not update the on-disk file size. If we update the + * on-disk file size and then the system crashes before the + * contents of the file are flushed to disk then the files + * may be full of holes (ie NULL files bug). + */ + error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, + XFS_ISIZE(ip)); + if (error) { + /* + * If we get an error at this point we simply don't + * bother truncating the file. + */ + xfs_trans_cancel(tp, + (XFS_TRANS_RELEASE_LOG_RES | + XFS_TRANS_ABORT)); + } else { + error = xfs_trans_commit(tp, + XFS_TRANS_RELEASE_LOG_RES); + if (!error) + xfs_inode_clear_eofblocks_tag(ip); + } + + xfs_iunlock(ip, XFS_ILOCK_EXCL); + if (need_iolock) + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + } + return error; +} + +/* + * xfs_alloc_file_space() + * This routine allocates disk space for the given file. + * + * If alloc_type == 0, this request is for an ALLOCSP type + * request which will change the file size. In this case, no + * DMAPI event will be generated by the call. A TRUNCATE event + * will be generated later by xfs_setattr. + * + * If alloc_type != 0, this request is for a RESVSP type + * request, and a DMAPI DM_EVENT_WRITE will be generated if the + * lower block boundary byte address is less than the file's + * length. + * + * RETURNS: + * 0 on success + * errno on error + * + */ +STATIC int +xfs_alloc_file_space( + xfs_inode_t *ip, + xfs_off_t offset, + xfs_off_t len, + int alloc_type, + int attr_flags) +{ + xfs_mount_t *mp = ip->i_mount; + xfs_off_t count; + xfs_filblks_t allocated_fsb; + xfs_filblks_t allocatesize_fsb; + xfs_extlen_t extsz, temp; + xfs_fileoff_t startoffset_fsb; + xfs_fsblock_t firstfsb; + int nimaps; + int quota_flag; + int rt; + xfs_trans_t *tp; + xfs_bmbt_irec_t imaps[1], *imapp; + xfs_bmap_free_t free_list; + uint qblocks, resblks, resrtextents; + int committed; + int error; + + trace_xfs_alloc_file_space(ip); + + if (XFS_FORCED_SHUTDOWN(mp)) + return XFS_ERROR(EIO); + + error = xfs_qm_dqattach(ip, 0); + if (error) + return error; + + if (len <= 0) + return XFS_ERROR(EINVAL); + + rt = XFS_IS_REALTIME_INODE(ip); + extsz = xfs_get_extsz_hint(ip); + + count = len; + imapp = &imaps[0]; + nimaps = 1; + startoffset_fsb = XFS_B_TO_FSBT(mp, offset); + allocatesize_fsb = XFS_B_TO_FSB(mp, count); + + /* + * Allocate file space until done or until there is an error + */ + while (allocatesize_fsb && !error) { + xfs_fileoff_t s, e; + + /* + * Determine space reservations for data/realtime. + */ + if (unlikely(extsz)) { + s = startoffset_fsb; + do_div(s, extsz); + s *= extsz; + e = startoffset_fsb + allocatesize_fsb; + if ((temp = do_mod(startoffset_fsb, extsz))) + e += temp; + if ((temp = do_mod(e, extsz))) + e += extsz - temp; + } else { + s = 0; + e = allocatesize_fsb; + } + + /* + * The transaction reservation is limited to a 32-bit block + * count, hence we need to limit the number of blocks we are + * trying to reserve to avoid an overflow. We can't allocate + * more than @nimaps extents, and an extent is limited on disk + * to MAXEXTLEN (21 bits), so use that to enforce the limit. + */ + resblks = min_t(xfs_fileoff_t, (e - s), (MAXEXTLEN * nimaps)); + if (unlikely(rt)) { + resrtextents = qblocks = resblks; + resrtextents /= mp->m_sb.sb_rextsize; + resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0); + quota_flag = XFS_QMOPT_RES_RTBLKS; + } else { + resrtextents = 0; + resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks); + quota_flag = XFS_QMOPT_RES_REGBLKS; + } + + /* + * Allocate and setup the transaction. + */ + tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT); + error = xfs_trans_reserve(tp, resblks, + XFS_WRITE_LOG_RES(mp), resrtextents, + XFS_TRANS_PERM_LOG_RES, + XFS_WRITE_LOG_COUNT); + /* + * Check for running out of space + */ + if (error) { + /* + * Free the transaction structure. + */ + ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp)); + xfs_trans_cancel(tp, 0); + break; + } + xfs_ilock(ip, XFS_ILOCK_EXCL); + error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks, + 0, quota_flag); + if (error) + goto error1; + + xfs_trans_ijoin(tp, ip, 0); + + xfs_bmap_init(&free_list, &firstfsb); + error = xfs_bmapi_write(tp, ip, startoffset_fsb, + allocatesize_fsb, alloc_type, &firstfsb, + 0, imapp, &nimaps, &free_list); + if (error) { + goto error0; + } + + /* + * Complete the transaction + */ + error = xfs_bmap_finish(&tp, &free_list, &committed); + if (error) { + goto error0; + } + + error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); + xfs_iunlock(ip, XFS_ILOCK_EXCL); + if (error) { + break; + } + + allocated_fsb = imapp->br_blockcount; + + if (nimaps == 0) { + error = XFS_ERROR(ENOSPC); + break; + } + + startoffset_fsb += allocated_fsb; + allocatesize_fsb -= allocated_fsb; + } + + return error; + +error0: /* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */ + xfs_bmap_cancel(&free_list); + xfs_trans_unreserve_quota_nblks(tp, ip, (long)qblocks, 0, quota_flag); + +error1: /* Just cancel transaction */ + xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT); + xfs_iunlock(ip, XFS_ILOCK_EXCL); + return error; +} + +/* + * Zero file bytes between startoff and endoff inclusive. + * The iolock is held exclusive and no blocks are buffered. + * + * This function is used by xfs_free_file_space() to zero + * partial blocks when the range to free is not block aligned. + * When unreserving space with boundaries that are not block + * aligned we round up the start and round down the end + * boundaries and then use this function to zero the parts of + * the blocks that got dropped during the rounding. + */ +STATIC int +xfs_zero_remaining_bytes( + xfs_inode_t *ip, + xfs_off_t startoff, + xfs_off_t endoff) +{ + xfs_bmbt_irec_t imap; + xfs_fileoff_t offset_fsb; + xfs_off_t lastoffset; + xfs_off_t offset; + xfs_buf_t *bp; + xfs_mount_t *mp = ip->i_mount; + int nimap; + int error = 0; + + /* + * Avoid doing I/O beyond eof - it's not necessary + * since nothing can read beyond eof. The space will + * be zeroed when the file is extended anyway. + */ + if (startoff >= XFS_ISIZE(ip)) + return 0; + + if (endoff > XFS_ISIZE(ip)) + endoff = XFS_ISIZE(ip); + + bp = xfs_buf_get_uncached(XFS_IS_REALTIME_INODE(ip) ? + mp->m_rtdev_targp : mp->m_ddev_targp, + BTOBB(mp->m_sb.sb_blocksize), 0); + if (!bp) + return XFS_ERROR(ENOMEM); + + xfs_buf_unlock(bp); + + for (offset = startoff; offset <= endoff; offset = lastoffset + 1) { + offset_fsb = XFS_B_TO_FSBT(mp, offset); + nimap = 1; + error = xfs_bmapi_read(ip, offset_fsb, 1, &imap, &nimap, 0); + if (error || nimap < 1) + break; + ASSERT(imap.br_blockcount >= 1); + ASSERT(imap.br_startoff == offset_fsb); + lastoffset = XFS_FSB_TO_B(mp, imap.br_startoff + 1) - 1; + if (lastoffset > endoff) + lastoffset = endoff; + if (imap.br_startblock == HOLESTARTBLOCK) + continue; + ASSERT(imap.br_startblock != DELAYSTARTBLOCK); + if (imap.br_state == XFS_EXT_UNWRITTEN) + continue; + XFS_BUF_UNDONE(bp); + XFS_BUF_UNWRITE(bp); + XFS_BUF_READ(bp); + XFS_BUF_SET_ADDR(bp, xfs_fsb_to_db(ip, imap.br_startblock)); + xfsbdstrat(mp, bp); + error = xfs_buf_iowait(bp); + if (error) { + xfs_buf_ioerror_alert(bp, + "xfs_zero_remaining_bytes(read)"); + break; + } + memset(bp->b_addr + + (offset - XFS_FSB_TO_B(mp, imap.br_startoff)), + 0, lastoffset - offset + 1); + XFS_BUF_UNDONE(bp); + XFS_BUF_UNREAD(bp); + XFS_BUF_WRITE(bp); + xfsbdstrat(mp, bp); + error = xfs_buf_iowait(bp); + if (error) { + xfs_buf_ioerror_alert(bp, + "xfs_zero_remaining_bytes(write)"); + break; + } + } + xfs_buf_free(bp); + return error; +} + +/* + * xfs_free_file_space() + * This routine frees disk space for the given file. + * + * This routine is only called by xfs_change_file_space + * for an UNRESVSP type call. + * + * RETURNS: + * 0 on success + * errno on error + * + */ +STATIC int +xfs_free_file_space( + xfs_inode_t *ip, + xfs_off_t offset, + xfs_off_t len, + int attr_flags) +{ + int committed; + int done; + xfs_fileoff_t endoffset_fsb; + int error; + xfs_fsblock_t firstfsb; + xfs_bmap_free_t free_list; + xfs_bmbt_irec_t imap; + xfs_off_t ioffset; + xfs_extlen_t mod=0; + xfs_mount_t *mp; + int nimap; + uint resblks; + xfs_off_t rounding; + int rt; + xfs_fileoff_t startoffset_fsb; + xfs_trans_t *tp; + int need_iolock = 1; + + mp = ip->i_mount; + + trace_xfs_free_file_space(ip); + + error = xfs_qm_dqattach(ip, 0); + if (error) + return error; + + error = 0; + if (len <= 0) /* if nothing being freed */ + return error; + rt = XFS_IS_REALTIME_INODE(ip); + startoffset_fsb = XFS_B_TO_FSB(mp, offset); + endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len); + + if (attr_flags & XFS_ATTR_NOLOCK) + need_iolock = 0; + if (need_iolock) { + xfs_ilock(ip, XFS_IOLOCK_EXCL); + /* wait for the completion of any pending DIOs */ + inode_dio_wait(VFS_I(ip)); + } + + rounding = max_t(xfs_off_t, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE); + ioffset = offset & ~(rounding - 1); + error = -filemap_write_and_wait_range(VFS_I(ip)->i_mapping, + ioffset, -1); + if (error) + goto out_unlock_iolock; + truncate_pagecache_range(VFS_I(ip), ioffset, -1); + + /* + * Need to zero the stuff we're not freeing, on disk. + * If it's a realtime file & can't use unwritten extents then we + * actually need to zero the extent edges. Otherwise xfs_bunmapi + * will take care of it for us. + */ + if (rt && !xfs_sb_version_hasextflgbit(&mp->m_sb)) { + nimap = 1; + error = xfs_bmapi_read(ip, startoffset_fsb, 1, + &imap, &nimap, 0); + if (error) + goto out_unlock_iolock; + ASSERT(nimap == 0 || nimap == 1); + if (nimap && imap.br_startblock != HOLESTARTBLOCK) { + xfs_daddr_t block; + + ASSERT(imap.br_startblock != DELAYSTARTBLOCK); + block = imap.br_startblock; + mod = do_div(block, mp->m_sb.sb_rextsize); + if (mod) + startoffset_fsb += mp->m_sb.sb_rextsize - mod; + } + nimap = 1; + error = xfs_bmapi_read(ip, endoffset_fsb - 1, 1, + &imap, &nimap, 0); + if (error) + goto out_unlock_iolock; + ASSERT(nimap == 0 || nimap == 1); + if (nimap && imap.br_startblock != HOLESTARTBLOCK) { + ASSERT(imap.br_startblock != DELAYSTARTBLOCK); + mod++; + if (mod && (mod != mp->m_sb.sb_rextsize)) + endoffset_fsb -= mod; + } + } + if ((done = (endoffset_fsb <= startoffset_fsb))) + /* + * One contiguous piece to clear + */ + error = xfs_zero_remaining_bytes(ip, offset, offset + len - 1); + else { + /* + * Some full blocks, possibly two pieces to clear + */ + if (offset < XFS_FSB_TO_B(mp, startoffset_fsb)) + error = xfs_zero_remaining_bytes(ip, offset, + XFS_FSB_TO_B(mp, startoffset_fsb) - 1); + if (!error && + XFS_FSB_TO_B(mp, endoffset_fsb) < offset + len) + error = xfs_zero_remaining_bytes(ip, + XFS_FSB_TO_B(mp, endoffset_fsb), + offset + len - 1); + } + + /* + * free file space until done or until there is an error + */ + resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0); + while (!error && !done) { + + /* + * allocate and setup the transaction. Allow this + * transaction to dip into the reserve blocks to ensure + * the freeing of the space succeeds at ENOSPC. + */ + tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT); + tp->t_flags |= XFS_TRANS_RESERVE; + error = xfs_trans_reserve(tp, + resblks, + XFS_WRITE_LOG_RES(mp), + 0, + XFS_TRANS_PERM_LOG_RES, + XFS_WRITE_LOG_COUNT); + + /* + * check for running out of space + */ + if (error) { + /* + * Free the transaction structure. + */ + ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp)); + xfs_trans_cancel(tp, 0); + break; + } + xfs_ilock(ip, XFS_ILOCK_EXCL); + error = xfs_trans_reserve_quota(tp, mp, + ip->i_udquot, ip->i_gdquot, ip->i_pdquot, + resblks, 0, XFS_QMOPT_RES_REGBLKS); + if (error) + goto error1; + + xfs_trans_ijoin(tp, ip, 0); + + /* + * issue the bunmapi() call to free the blocks + */ + xfs_bmap_init(&free_list, &firstfsb); + error = xfs_bunmapi(tp, ip, startoffset_fsb, + endoffset_fsb - startoffset_fsb, + 0, 2, &firstfsb, &free_list, &done); + if (error) { + goto error0; + } + + /* + * complete the transaction + */ + error = xfs_bmap_finish(&tp, &free_list, &committed); + if (error) { + goto error0; + } + + error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); + xfs_iunlock(ip, XFS_ILOCK_EXCL); + } + + out_unlock_iolock: + if (need_iolock) + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + return error; + + error0: + xfs_bmap_cancel(&free_list); + error1: + xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT); + xfs_iunlock(ip, need_iolock ? (XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL) : + XFS_ILOCK_EXCL); + return error; +} + + +STATIC int +xfs_zero_file_space( + struct xfs_inode *ip, + xfs_off_t offset, + xfs_off_t len, + int attr_flags) +{ + struct xfs_mount *mp = ip->i_mount; + uint granularity; + xfs_off_t start_boundary; + xfs_off_t end_boundary; + int error; + + granularity = max_t(uint, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE); + + /* + * Round the range of extents we are going to convert inwards. If the + * offset is aligned, then it doesn't get changed so we zero from the + * start of the block offset points to. + */ + start_boundary = round_up(offset, granularity); + end_boundary = round_down(offset + len, granularity); + + ASSERT(start_boundary >= offset); + ASSERT(end_boundary <= offset + len); + + if (!(attr_flags & XFS_ATTR_NOLOCK)) + xfs_ilock(ip, XFS_IOLOCK_EXCL); + + if (start_boundary < end_boundary - 1) { + /* punch out the page cache over the conversion range */ + truncate_pagecache_range(VFS_I(ip), start_boundary, + end_boundary - 1); + /* convert the blocks */ + error = xfs_alloc_file_space(ip, start_boundary, + end_boundary - start_boundary - 1, + XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT, + attr_flags); + if (error) + goto out_unlock; + + /* We've handled the interior of the range, now for the edges */ + if (start_boundary != offset) + error = xfs_iozero(ip, offset, start_boundary - offset); + if (error) + goto out_unlock; + + if (end_boundary != offset + len) + error = xfs_iozero(ip, end_boundary, + offset + len - end_boundary); + + } else { + /* + * It's either a sub-granularity range or the range spanned lies + * partially across two adjacent blocks. + */ + error = xfs_iozero(ip, offset, len); + } + +out_unlock: + if (!(attr_flags & XFS_ATTR_NOLOCK)) + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + return error; + +} + +/* + * xfs_change_file_space() + * This routine allocates or frees disk space for the given file. + * The user specified parameters are checked for alignment and size + * limitations. + * + * RETURNS: + * 0 on success + * errno on error + * + */ +int +xfs_change_file_space( + xfs_inode_t *ip, + int cmd, + xfs_flock64_t *bf, + xfs_off_t offset, + int attr_flags) +{ + xfs_mount_t *mp = ip->i_mount; + int clrprealloc; + int error; + xfs_fsize_t fsize; + int setprealloc; + xfs_off_t startoffset; + xfs_trans_t *tp; + struct iattr iattr; + + if (!S_ISREG(ip->i_d.di_mode)) + return XFS_ERROR(EINVAL); + + switch (bf->l_whence) { + case 0: /*SEEK_SET*/ + break; + case 1: /*SEEK_CUR*/ + bf->l_start += offset; + break; + case 2: /*SEEK_END*/ + bf->l_start += XFS_ISIZE(ip); + break; + default: + return XFS_ERROR(EINVAL); + } + + /* + * length of <= 0 for resv/unresv/zero is invalid. length for + * alloc/free is ignored completely and we have no idea what userspace + * might have set it to, so set it to zero to allow range + * checks to pass. + */ + switch (cmd) { + case XFS_IOC_ZERO_RANGE: + case XFS_IOC_RESVSP: + case XFS_IOC_RESVSP64: + case XFS_IOC_UNRESVSP: + case XFS_IOC_UNRESVSP64: + if (bf->l_len <= 0) + return XFS_ERROR(EINVAL); + break; + default: + bf->l_len = 0; + break; + } + + if (bf->l_start < 0 || + bf->l_start > mp->m_super->s_maxbytes || + bf->l_start + bf->l_len < 0 || + bf->l_start + bf->l_len >= mp->m_super->s_maxbytes) + return XFS_ERROR(EINVAL); + + bf->l_whence = 0; + + startoffset = bf->l_start; + fsize = XFS_ISIZE(ip); + + setprealloc = clrprealloc = 0; + switch (cmd) { + case XFS_IOC_ZERO_RANGE: + error = xfs_zero_file_space(ip, startoffset, bf->l_len, + attr_flags); + if (error) + return error; + setprealloc = 1; + break; + + case XFS_IOC_RESVSP: + case XFS_IOC_RESVSP64: + error = xfs_alloc_file_space(ip, startoffset, bf->l_len, + XFS_BMAPI_PREALLOC, attr_flags); + if (error) + return error; + setprealloc = 1; + break; + + case XFS_IOC_UNRESVSP: + case XFS_IOC_UNRESVSP64: + if ((error = xfs_free_file_space(ip, startoffset, bf->l_len, + attr_flags))) + return error; + break; + + case XFS_IOC_ALLOCSP: + case XFS_IOC_ALLOCSP64: + case XFS_IOC_FREESP: + case XFS_IOC_FREESP64: + /* + * These operations actually do IO when extending the file, but + * the allocation is done seperately to the zeroing that is + * done. This set of operations need to be serialised against + * other IO operations, such as truncate and buffered IO. We + * need to take the IOLOCK here to serialise the allocation and + * zeroing IO to prevent other IOLOCK holders (e.g. getbmap, + * truncate, direct IO) from racing against the transient + * allocated but not written state we can have here. + */ + xfs_ilock(ip, XFS_IOLOCK_EXCL); + if (startoffset > fsize) { + error = xfs_alloc_file_space(ip, fsize, + startoffset - fsize, 0, + attr_flags | XFS_ATTR_NOLOCK); + if (error) { + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + break; + } + } + + iattr.ia_valid = ATTR_SIZE; + iattr.ia_size = startoffset; + + error = xfs_setattr_size(ip, &iattr, + attr_flags | XFS_ATTR_NOLOCK); + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + + if (error) + return error; + + clrprealloc = 1; + break; + + default: + ASSERT(0); + return XFS_ERROR(EINVAL); + } + + /* + * update the inode timestamp, mode, and prealloc flag bits + */ + tp = xfs_trans_alloc(mp, XFS_TRANS_WRITEID); + + if ((error = xfs_trans_reserve(tp, 0, XFS_WRITEID_LOG_RES(mp), + 0, 0, 0))) { + /* ASSERT(0); */ + xfs_trans_cancel(tp, 0); + return error; + } + + xfs_ilock(ip, XFS_ILOCK_EXCL); + xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL); + + if ((attr_flags & XFS_ATTR_DMI) == 0) { + ip->i_d.di_mode &= ~S_ISUID; + + /* + * Note that we don't have to worry about mandatory + * file locking being disabled here because we only + * clear the S_ISGID bit if the Group execute bit is + * on, but if it was on then mandatory locking wouldn't + * have been enabled. + */ + if (ip->i_d.di_mode & S_IXGRP) + ip->i_d.di_mode &= ~S_ISGID; + + xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + } + if (setprealloc) + ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC; + else if (clrprealloc) + ip->i_d.di_flags &= ~XFS_DIFLAG_PREALLOC; + + xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); + if (attr_flags & XFS_ATTR_SYNC) + xfs_trans_set_sync(tp); + return xfs_trans_commit(tp, 0); +} |