diff options
Diffstat (limited to 'fs/xfs/xfs_file.c')
-rw-r--r-- | fs/xfs/xfs_file.c | 470 |
1 files changed, 385 insertions, 85 deletions
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 9f7ec15a6522..de3dc98f4e8f 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -31,11 +31,15 @@ #include "xfs_error.h" #include "xfs_vnodeops.h" #include "xfs_da_btree.h" +#include "xfs_dir2_format.h" +#include "xfs_dir2_priv.h" #include "xfs_ioctl.h" #include "xfs_trace.h" +#include <linux/aio.h> #include <linux/dcache.h> #include <linux/falloc.h> +#include <linux/pagevec.h> static const struct vm_operations_struct xfs_file_vm_ops; @@ -83,7 +87,7 @@ xfs_rw_ilock_demote( * valid before the operation, it will be read from disk before * being partially zeroed. */ -STATIC int +int xfs_iozero( struct xfs_inode *ip, /* inode */ loff_t pos, /* offset in file */ @@ -236,7 +240,6 @@ xfs_file_aio_read( ssize_t ret = 0; int ioflags = 0; xfs_fsize_t n; - unsigned long seg; XFS_STATS_INC(xs_read_calls); @@ -247,33 +250,22 @@ xfs_file_aio_read( if (file->f_mode & FMODE_NOCMTIME) ioflags |= IO_INVIS; - /* START copy & waste from filemap.c */ - for (seg = 0; seg < nr_segs; seg++) { - const struct iovec *iv = &iovp[seg]; - - /* - * If any segment has a negative length, or the cumulative - * length ever wraps negative then return -EINVAL. - */ - size += iv->iov_len; - if (unlikely((ssize_t)(size|iv->iov_len) < 0)) - return XFS_ERROR(-EINVAL); - } - /* END copy & waste from filemap.c */ + ret = generic_segment_checks(iovp, &nr_segs, &size, VERIFY_WRITE); + if (ret < 0) + return ret; if (unlikely(ioflags & IO_ISDIRECT)) { xfs_buftarg_t *target = XFS_IS_REALTIME_INODE(ip) ? mp->m_rtdev_targp : mp->m_ddev_targp; - if ((iocb->ki_pos & target->bt_smask) || - (size & target->bt_smask)) { - if (iocb->ki_pos == i_size_read(inode)) + if ((pos & target->bt_smask) || (size & target->bt_smask)) { + if (pos == i_size_read(inode)) return 0; return -XFS_ERROR(EINVAL); } } - n = XFS_MAXIOFFSET(mp) - iocb->ki_pos; + n = mp->m_super->s_maxbytes - pos; if (n <= 0 || size == 0) return 0; @@ -299,20 +291,21 @@ xfs_file_aio_read( xfs_rw_ilock(ip, XFS_IOLOCK_EXCL); if (inode->i_mapping->nrpages) { - ret = -xfs_flushinval_pages(ip, - (iocb->ki_pos & PAGE_CACHE_MASK), - -1, FI_REMAPF_LOCKED); + ret = -filemap_write_and_wait_range( + VFS_I(ip)->i_mapping, + pos, -1); if (ret) { xfs_rw_iunlock(ip, XFS_IOLOCK_EXCL); return ret; } + truncate_pagecache_range(VFS_I(ip), pos, -1); } xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL); } - trace_xfs_file_read(ip, size, iocb->ki_pos, ioflags); + trace_xfs_file_read(ip, size, pos, ioflags); - ret = generic_file_aio_read(iocb, iovp, nr_segs, iocb->ki_pos); + ret = generic_file_aio_read(iocb, iovp, nr_segs, pos); if (ret > 0) XFS_STATS_ADD(xs_read_bytes, ret); @@ -680,10 +673,11 @@ xfs_file_dio_aio_write( goto out; if (mapping->nrpages) { - ret = -xfs_flushinval_pages(ip, (pos & PAGE_CACHE_MASK), -1, - FI_REMAPF_LOCKED); + ret = -filemap_write_and_wait_range(VFS_I(ip)->i_mapping, + pos, -1); if (ret) goto out; + truncate_pagecache_range(VFS_I(ip), pos, -1); } /* @@ -738,16 +732,17 @@ xfs_file_buffered_aio_write( write_retry: trace_xfs_file_buffered_write(ip, count, iocb->ki_pos, 0); ret = generic_file_buffered_write(iocb, iovp, nr_segs, - pos, &iocb->ki_pos, count, ret); + pos, &iocb->ki_pos, count, 0); + /* - * if we just got an ENOSPC, flush the inode now we aren't holding any - * page locks and retry *once* + * If we just got an ENOSPC, try to write back all dirty inodes to + * convert delalloc space to free up some of the excess reserved + * metadata space. */ if (ret == -ENOSPC && !enospc) { enospc = 1; - ret = -xfs_flush_pages(ip, 0, -1, 0, FI_NONE); - if (!ret) - goto write_retry; + xfs_flush_inodes(ip->i_mount); + goto write_retry; } current->backing_dev_info = NULL; @@ -781,10 +776,10 @@ xfs_file_aio_write( if (ocount == 0) return 0; - xfs_wait_for_freeze(ip->i_mount, SB_FREEZE_WRITE); - - if (XFS_FORCED_SHUTDOWN(ip->i_mount)) - return -EIO; + if (XFS_FORCED_SHUTDOWN(ip->i_mount)) { + ret = -EIO; + goto out; + } if (unlikely(file->f_flags & O_DIRECT)) ret = xfs_file_dio_aio_write(iocb, iovp, nr_segs, pos, ocount); @@ -803,6 +798,7 @@ xfs_file_aio_write( ret = err; } +out: return ret; } @@ -813,7 +809,7 @@ xfs_file_fallocate( loff_t offset, loff_t len) { - struct inode *inode = file->f_path.dentry->d_inode; + struct inode *inode = file_inode(file); long error; loff_t new_size = 0; xfs_flock64_t bf; @@ -895,7 +891,7 @@ xfs_dir_open( */ mode = xfs_ilock_map_shared(ip); if (ip->i_d.di_nextents > 0) - xfs_da_reada_buf(NULL, ip, 0, XFS_DATA_FORK); + xfs_dir3_data_readahead(NULL, ip, 0, -1); xfs_iunlock(ip, mode); return 0; } @@ -910,11 +906,10 @@ xfs_file_release( STATIC int xfs_file_readdir( - struct file *filp, - void *dirent, - filldir_t filldir) + struct file *file, + struct dir_context *ctx) { - struct inode *inode = filp->f_path.dentry->d_inode; + struct inode *inode = file_inode(file); xfs_inode_t *ip = XFS_I(inode); int error; size_t bufsize; @@ -933,8 +928,7 @@ xfs_file_readdir( */ bufsize = (size_t)min_t(loff_t, 32768, ip->i_d.di_size); - error = xfs_readdir(ip, dirent, bufsize, - (xfs_off_t *)&filp->f_pos, filldir); + error = xfs_readdir(ip, ctx, bufsize); if (error) return -error; return 0; @@ -946,7 +940,6 @@ xfs_file_mmap( struct vm_area_struct *vma) { vma->vm_ops = &xfs_file_vm_ops; - vma->vm_flags |= VM_CAN_NONLINEAR; file_accessed(filp); return 0; @@ -966,17 +959,232 @@ xfs_vm_page_mkwrite( return block_page_mkwrite(vma, vmf, xfs_get_blocks); } +/* + * This type is designed to indicate the type of offset we would like + * to search from page cache for either xfs_seek_data() or xfs_seek_hole(). + */ +enum { + HOLE_OFF = 0, + DATA_OFF, +}; + +/* + * Lookup the desired type of offset from the given page. + * + * On success, return true and the offset argument will point to the + * start of the region that was found. Otherwise this function will + * return false and keep the offset argument unchanged. + */ +STATIC bool +xfs_lookup_buffer_offset( + struct page *page, + loff_t *offset, + unsigned int type) +{ + loff_t lastoff = page_offset(page); + bool found = false; + struct buffer_head *bh, *head; + + bh = head = page_buffers(page); + do { + /* + * Unwritten extents that have data in the page + * cache covering them can be identified by the + * BH_Unwritten state flag. Pages with multiple + * buffers might have a mix of holes, data and + * unwritten extents - any buffer with valid + * data in it should have BH_Uptodate flag set + * on it. + */ + if (buffer_unwritten(bh) || + buffer_uptodate(bh)) { + if (type == DATA_OFF) + found = true; + } else { + if (type == HOLE_OFF) + found = true; + } + + if (found) { + *offset = lastoff; + break; + } + lastoff += bh->b_size; + } while ((bh = bh->b_this_page) != head); + + return found; +} + +/* + * This routine is called to find out and return a data or hole offset + * from the page cache for unwritten extents according to the desired + * type for xfs_seek_data() or xfs_seek_hole(). + * + * The argument offset is used to tell where we start to search from the + * page cache. Map is used to figure out the end points of the range to + * lookup pages. + * + * Return true if the desired type of offset was found, and the argument + * offset is filled with that address. Otherwise, return false and keep + * offset unchanged. + */ +STATIC bool +xfs_find_get_desired_pgoff( + struct inode *inode, + struct xfs_bmbt_irec *map, + unsigned int type, + loff_t *offset) +{ + struct xfs_inode *ip = XFS_I(inode); + struct xfs_mount *mp = ip->i_mount; + struct pagevec pvec; + pgoff_t index; + pgoff_t end; + loff_t endoff; + loff_t startoff = *offset; + loff_t lastoff = startoff; + bool found = false; + + pagevec_init(&pvec, 0); + + index = startoff >> PAGE_CACHE_SHIFT; + endoff = XFS_FSB_TO_B(mp, map->br_startoff + map->br_blockcount); + end = endoff >> PAGE_CACHE_SHIFT; + do { + int want; + unsigned nr_pages; + unsigned int i; + + want = min_t(pgoff_t, end - index, PAGEVEC_SIZE); + nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index, + want); + /* + * No page mapped into given range. If we are searching holes + * and if this is the first time we got into the loop, it means + * that the given offset is landed in a hole, return it. + * + * If we have already stepped through some block buffers to find + * holes but they all contains data. In this case, the last + * offset is already updated and pointed to the end of the last + * mapped page, if it does not reach the endpoint to search, + * that means there should be a hole between them. + */ + if (nr_pages == 0) { + /* Data search found nothing */ + if (type == DATA_OFF) + break; + + ASSERT(type == HOLE_OFF); + if (lastoff == startoff || lastoff < endoff) { + found = true; + *offset = lastoff; + } + break; + } + + /* + * At lease we found one page. If this is the first time we + * step into the loop, and if the first page index offset is + * greater than the given search offset, a hole was found. + */ + if (type == HOLE_OFF && lastoff == startoff && + lastoff < page_offset(pvec.pages[0])) { + found = true; + break; + } + + for (i = 0; i < nr_pages; i++) { + struct page *page = pvec.pages[i]; + loff_t b_offset; + + /* + * At this point, the page may be truncated or + * invalidated (changing page->mapping to NULL), + * or even swizzled back from swapper_space to tmpfs + * file mapping. However, page->index will not change + * because we have a reference on the page. + * + * Searching done if the page index is out of range. + * If the current offset is not reaches the end of + * the specified search range, there should be a hole + * between them. + */ + if (page->index > end) { + if (type == HOLE_OFF && lastoff < endoff) { + *offset = lastoff; + found = true; + } + goto out; + } + + lock_page(page); + /* + * Page truncated or invalidated(page->mapping == NULL). + * We can freely skip it and proceed to check the next + * page. + */ + if (unlikely(page->mapping != inode->i_mapping)) { + unlock_page(page); + continue; + } + + if (!page_has_buffers(page)) { + unlock_page(page); + continue; + } + + found = xfs_lookup_buffer_offset(page, &b_offset, type); + if (found) { + /* + * The found offset may be less than the start + * point to search if this is the first time to + * come here. + */ + *offset = max_t(loff_t, startoff, b_offset); + unlock_page(page); + goto out; + } + + /* + * We either searching data but nothing was found, or + * searching hole but found a data buffer. In either + * case, probably the next page contains the desired + * things, update the last offset to it so. + */ + lastoff = page_offset(page) + PAGE_SIZE; + unlock_page(page); + } + + /* + * The number of returned pages less than our desired, search + * done. In this case, nothing was found for searching data, + * but we found a hole behind the last offset. + */ + if (nr_pages < want) { + if (type == HOLE_OFF) { + *offset = lastoff; + found = true; + } + break; + } + + index = pvec.pages[i - 1]->index + 1; + pagevec_release(&pvec); + } while (index <= end); + +out: + pagevec_release(&pvec); + return found; +} + STATIC loff_t xfs_seek_data( struct file *file, - loff_t start, - u32 type) + loff_t start) { struct inode *inode = file->f_mapping->host; struct xfs_inode *ip = XFS_I(inode); struct xfs_mount *mp = ip->i_mount; - struct xfs_bmbt_irec map[2]; - int nmap = 2; loff_t uninitialized_var(offset); xfs_fsize_t isize; xfs_fileoff_t fsbno; @@ -992,38 +1200,75 @@ xfs_seek_data( goto out_unlock; } - fsbno = XFS_B_TO_FSBT(mp, start); - /* * Try to read extents from the first block indicated * by fsbno to the end block of the file. */ + fsbno = XFS_B_TO_FSBT(mp, start); end = XFS_B_TO_FSB(mp, isize); + for (;;) { + struct xfs_bmbt_irec map[2]; + int nmap = 2; + unsigned int i; - error = xfs_bmapi_read(ip, fsbno, end - fsbno, map, &nmap, - XFS_BMAPI_ENTIRE); - if (error) - goto out_unlock; + error = xfs_bmapi_read(ip, fsbno, end - fsbno, map, &nmap, + XFS_BMAPI_ENTIRE); + if (error) + goto out_unlock; - /* - * Treat unwritten extent as data extent since it might - * contains dirty data in page cache. - */ - if (map[0].br_startblock != HOLESTARTBLOCK) { - offset = max_t(loff_t, start, - XFS_FSB_TO_B(mp, map[0].br_startoff)); - } else { + /* No extents at given offset, must be beyond EOF */ + if (nmap == 0) { + error = ENXIO; + goto out_unlock; + } + + for (i = 0; i < nmap; i++) { + offset = max_t(loff_t, start, + XFS_FSB_TO_B(mp, map[i].br_startoff)); + + /* Landed in a data extent */ + if (map[i].br_startblock == DELAYSTARTBLOCK || + (map[i].br_state == XFS_EXT_NORM && + !isnullstartblock(map[i].br_startblock))) + goto out; + + /* + * Landed in an unwritten extent, try to search data + * from page cache. + */ + if (map[i].br_state == XFS_EXT_UNWRITTEN) { + if (xfs_find_get_desired_pgoff(inode, &map[i], + DATA_OFF, &offset)) + goto out; + } + } + + /* + * map[0] is hole or its an unwritten extent but + * without data in page cache. Probably means that + * we are reading after EOF if nothing in map[1]. + */ if (nmap == 1) { error = ENXIO; goto out_unlock; } - offset = max_t(loff_t, start, - XFS_FSB_TO_B(mp, map[1].br_startoff)); + ASSERT(i > 1); + + /* + * Nothing was found, proceed to the next round of search + * if reading offset not beyond or hit EOF. + */ + fsbno = map[i - 1].br_startoff + map[i - 1].br_blockcount; + start = XFS_FSB_TO_B(mp, fsbno); + if (start >= isize) { + error = ENXIO; + goto out_unlock; + } } - if (offset != file->f_pos) - file->f_pos = offset; +out: + offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes); out_unlock: xfs_iunlock_map_shared(ip, lock); @@ -1036,16 +1281,15 @@ out_unlock: STATIC loff_t xfs_seek_hole( struct file *file, - loff_t start, - u32 type) + loff_t start) { struct inode *inode = file->f_mapping->host; struct xfs_inode *ip = XFS_I(inode); struct xfs_mount *mp = ip->i_mount; loff_t uninitialized_var(offset); - loff_t holeoff; xfs_fsize_t isize; xfs_fileoff_t fsbno; + xfs_filblks_t end; uint lock; int error; @@ -1061,23 +1305,78 @@ xfs_seek_hole( } fsbno = XFS_B_TO_FSBT(mp, start); - error = xfs_bmap_first_unused(NULL, ip, 1, &fsbno, XFS_DATA_FORK); - if (error) - goto out_unlock; + end = XFS_B_TO_FSB(mp, isize); + + for (;;) { + struct xfs_bmbt_irec map[2]; + int nmap = 2; + unsigned int i; + + error = xfs_bmapi_read(ip, fsbno, end - fsbno, map, &nmap, + XFS_BMAPI_ENTIRE); + if (error) + goto out_unlock; + + /* No extents at given offset, must be beyond EOF */ + if (nmap == 0) { + error = ENXIO; + goto out_unlock; + } + + for (i = 0; i < nmap; i++) { + offset = max_t(loff_t, start, + XFS_FSB_TO_B(mp, map[i].br_startoff)); + + /* Landed in a hole */ + if (map[i].br_startblock == HOLESTARTBLOCK) + goto out; + + /* + * Landed in an unwritten extent, try to search hole + * from page cache. + */ + if (map[i].br_state == XFS_EXT_UNWRITTEN) { + if (xfs_find_get_desired_pgoff(inode, &map[i], + HOLE_OFF, &offset)) + goto out; + } + } + + /* + * map[0] contains data or its unwritten but contains + * data in page cache, probably means that we are + * reading after EOF. We should fix offset to point + * to the end of the file(i.e., there is an implicit + * hole at the end of any file). + */ + if (nmap == 1) { + offset = isize; + break; + } + + ASSERT(i > 1); - holeoff = XFS_FSB_TO_B(mp, fsbno); - if (holeoff <= start) - offset = start; - else { /* - * xfs_bmap_first_unused() could return a value bigger than - * isize if there are no more holes past the supplied offset. + * Both mappings contains data, proceed to the next round of + * search if the current reading offset not beyond or hit EOF. */ - offset = min_t(loff_t, holeoff, isize); + fsbno = map[i - 1].br_startoff + map[i - 1].br_blockcount; + start = XFS_FSB_TO_B(mp, fsbno); + if (start >= isize) { + offset = isize; + break; + } } - if (offset != file->f_pos) - file->f_pos = offset; +out: + /* + * At this point, we must have found a hole. However, the returned + * offset may be bigger than the file size as it may be aligned to + * page boundary for unwritten extents, we need to deal with this + * situation in particular. + */ + offset = min_t(loff_t, offset, isize); + offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes); out_unlock: xfs_iunlock_map_shared(ip, lock); @@ -1099,9 +1398,9 @@ xfs_file_llseek( case SEEK_SET: return generic_file_llseek(file, offset, origin); case SEEK_DATA: - return xfs_seek_data(file, offset, origin); + return xfs_seek_data(file, offset); case SEEK_HOLE: - return xfs_seek_hole(file, offset, origin); + return xfs_seek_hole(file, offset); default: return -EINVAL; } @@ -1129,7 +1428,7 @@ const struct file_operations xfs_file_operations = { const struct file_operations xfs_dir_file_operations = { .open = xfs_dir_open, .read = generic_read_dir, - .readdir = xfs_file_readdir, + .iterate = xfs_file_readdir, .llseek = generic_file_llseek, .unlocked_ioctl = xfs_file_ioctl, #ifdef CONFIG_COMPAT @@ -1141,4 +1440,5 @@ const struct file_operations xfs_dir_file_operations = { static const struct vm_operations_struct xfs_file_vm_ops = { .fault = filemap_fault, .page_mkwrite = xfs_vm_page_mkwrite, + .remap_pages = generic_file_remap_pages, }; |