| /* |
| * linux/fs/ext4/file.c |
| * |
| * Copyright (C) 1992, 1993, 1994, 1995 |
| * Remy Card (card@masi.ibp.fr) |
| * Laboratoire MASI - Institut Blaise Pascal |
| * Universite Pierre et Marie Curie (Paris VI) |
| * |
| * from |
| * |
| * linux/fs/minix/file.c |
| * |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| * |
| * ext4 fs regular file handling primitives |
| * |
| * 64-bit file support on 64-bit platforms by Jakub Jelinek |
| * (jj@sunsite.ms.mff.cuni.cz) |
| */ |
| |
| #include <linux/time.h> |
| #include <linux/fs.h> |
| #include <linux/mount.h> |
| #include <linux/path.h> |
| #include <linux/dax.h> |
| #include <linux/quotaops.h> |
| #include <linux/pagevec.h> |
| #include <linux/uio.h> |
| #include "ext4.h" |
| #include "ext4_jbd2.h" |
| #include "xattr.h" |
| #include "acl.h" |
| |
| /* |
| * Called when an inode is released. Note that this is different |
| * from ext4_file_open: open gets called at every open, but release |
| * gets called only when /all/ the files are closed. |
| */ |
| static int ext4_release_file(struct inode *inode, struct file *filp) |
| { |
| if (ext4_test_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE)) { |
| ext4_alloc_da_blocks(inode); |
| ext4_clear_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE); |
| } |
| /* if we are the last writer on the inode, drop the block reservation */ |
| if ((filp->f_mode & FMODE_WRITE) && |
| (atomic_read(&inode->i_writecount) == 1) && |
| !EXT4_I(inode)->i_reserved_data_blocks) |
| { |
| down_write(&EXT4_I(inode)->i_data_sem); |
| ext4_discard_preallocations(inode); |
| up_write(&EXT4_I(inode)->i_data_sem); |
| } |
| if (is_dx(inode) && filp->private_data) |
| ext4_htree_free_dir_info(filp->private_data); |
| |
| return 0; |
| } |
| |
| static void ext4_unwritten_wait(struct inode *inode) |
| { |
| wait_queue_head_t *wq = ext4_ioend_wq(inode); |
| |
| wait_event(*wq, (atomic_read(&EXT4_I(inode)->i_unwritten) == 0)); |
| } |
| |
| /* |
| * This tests whether the IO in question is block-aligned or not. |
| * Ext4 utilizes unwritten extents when hole-filling during direct IO, and they |
| * are converted to written only after the IO is complete. Until they are |
| * mapped, these blocks appear as holes, so dio_zero_block() will assume that |
| * it needs to zero out portions of the start and/or end block. If 2 AIO |
| * threads are at work on the same unwritten block, they must be synchronized |
| * or one thread will zero the other's data, causing corruption. |
| */ |
| static int |
| ext4_unaligned_aio(struct inode *inode, struct iov_iter *from, loff_t pos) |
| { |
| struct super_block *sb = inode->i_sb; |
| int blockmask = sb->s_blocksize - 1; |
| |
| if (pos >= i_size_read(inode)) |
| return 0; |
| |
| if ((pos | iov_iter_alignment(from)) & blockmask) |
| return 1; |
| |
| return 0; |
| } |
| |
| static ssize_t |
| ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from) |
| { |
| struct file *file = iocb->ki_filp; |
| struct inode *inode = file_inode(iocb->ki_filp); |
| struct mutex *aio_mutex = NULL; |
| struct blk_plug plug; |
| int o_direct = iocb->ki_flags & IOCB_DIRECT; |
| int overwrite = 0; |
| ssize_t ret; |
| |
| /* |
| * Unaligned direct AIO must be serialized; see comment above |
| * In the case of O_APPEND, assume that we must always serialize |
| */ |
| if (o_direct && |
| ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) && |
| !is_sync_kiocb(iocb) && |
| (iocb->ki_flags & IOCB_APPEND || |
| ext4_unaligned_aio(inode, from, iocb->ki_pos))) { |
| aio_mutex = ext4_aio_mutex(inode); |
| mutex_lock(aio_mutex); |
| ext4_unwritten_wait(inode); |
| } |
| |
| mutex_lock(&inode->i_mutex); |
| ret = generic_write_checks(iocb, from); |
| if (ret <= 0) |
| goto out; |
| |
| /* |
| * If we have encountered a bitmap-format file, the size limit |
| * is smaller than s_maxbytes, which is for extent-mapped files. |
| */ |
| if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) { |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| |
| if (iocb->ki_pos >= sbi->s_bitmap_maxbytes) { |
| ret = -EFBIG; |
| goto out; |
| } |
| iov_iter_truncate(from, sbi->s_bitmap_maxbytes - iocb->ki_pos); |
| } |
| |
| iocb->private = &overwrite; |
| if (o_direct) { |
| size_t length = iov_iter_count(from); |
| loff_t pos = iocb->ki_pos; |
| blk_start_plug(&plug); |
| |
| /* check whether we do a DIO overwrite or not */ |
| if (ext4_should_dioread_nolock(inode) && !aio_mutex && |
| !file->f_mapping->nrpages && pos + length <= i_size_read(inode)) { |
| struct ext4_map_blocks map; |
| unsigned int blkbits = inode->i_blkbits; |
| int err, len; |
| |
| map.m_lblk = pos >> blkbits; |
| map.m_len = (EXT4_BLOCK_ALIGN(pos + length, blkbits) >> blkbits) |
| - map.m_lblk; |
| len = map.m_len; |
| |
| err = ext4_map_blocks(NULL, inode, &map, 0); |
| /* |
| * 'err==len' means that all of blocks has |
| * been preallocated no matter they are |
| * initialized or not. For excluding |
| * unwritten extents, we need to check |
| * m_flags. There are two conditions that |
| * indicate for initialized extents. 1) If we |
| * hit extent cache, EXT4_MAP_MAPPED flag is |
| * returned; 2) If we do a real lookup, |
| * non-flags are returned. So we should check |
| * these two conditions. |
| */ |
| if (err == len && (map.m_flags & EXT4_MAP_MAPPED)) |
| overwrite = 1; |
| } |
| } |
| |
| ret = __generic_file_write_iter(iocb, from); |
| mutex_unlock(&inode->i_mutex); |
| |
| if (ret > 0) { |
| ssize_t err; |
| |
| err = generic_write_sync(file, iocb->ki_pos - ret, ret); |
| if (err < 0) |
| ret = err; |
| } |
| if (o_direct) |
| blk_finish_plug(&plug); |
| |
| if (aio_mutex) |
| mutex_unlock(aio_mutex); |
| return ret; |
| |
| out: |
| mutex_unlock(&inode->i_mutex); |
| if (aio_mutex) |
| mutex_unlock(aio_mutex); |
| return ret; |
| } |
| |
| #ifdef CONFIG_FS_DAX |
| static void ext4_end_io_unwritten(struct buffer_head *bh, int uptodate) |
| { |
| struct inode *inode = bh->b_assoc_map->host; |
| /* XXX: breaks on 32-bit > 16TB. Is that even supported? */ |
| loff_t offset = (loff_t)(uintptr_t)bh->b_private << inode->i_blkbits; |
| int err; |
| if (!uptodate) |
| return; |
| WARN_ON(!buffer_unwritten(bh)); |
| err = ext4_convert_unwritten_extents(NULL, inode, offset, bh->b_size); |
| } |
| |
| static int ext4_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
| { |
| int result; |
| handle_t *handle = NULL; |
| struct inode *inode = file_inode(vma->vm_file); |
| struct super_block *sb = inode->i_sb; |
| bool write = vmf->flags & FAULT_FLAG_WRITE; |
| |
| if (write) { |
| sb_start_pagefault(sb); |
| file_update_time(vma->vm_file); |
| down_read(&EXT4_I(inode)->i_mmap_sem); |
| handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE, |
| EXT4_DATA_TRANS_BLOCKS(sb)); |
| } else |
| down_read(&EXT4_I(inode)->i_mmap_sem); |
| |
| if (IS_ERR(handle)) |
| result = VM_FAULT_SIGBUS; |
| else |
| result = __dax_fault(vma, vmf, ext4_get_block_dax, |
| ext4_end_io_unwritten); |
| |
| if (write) { |
| if (!IS_ERR(handle)) |
| ext4_journal_stop(handle); |
| up_read(&EXT4_I(inode)->i_mmap_sem); |
| sb_end_pagefault(sb); |
| } else |
| up_read(&EXT4_I(inode)->i_mmap_sem); |
| |
| return result; |
| } |
| |
| static int ext4_dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr, |
| pmd_t *pmd, unsigned int flags) |
| { |
| int result; |
| handle_t *handle = NULL; |
| struct inode *inode = file_inode(vma->vm_file); |
| struct super_block *sb = inode->i_sb; |
| bool write = flags & FAULT_FLAG_WRITE; |
| |
| if (write) { |
| sb_start_pagefault(sb); |
| file_update_time(vma->vm_file); |
| down_read(&EXT4_I(inode)->i_mmap_sem); |
| handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE, |
| ext4_chunk_trans_blocks(inode, |
| PMD_SIZE / PAGE_SIZE)); |
| } else |
| down_read(&EXT4_I(inode)->i_mmap_sem); |
| |
| if (IS_ERR(handle)) |
| result = VM_FAULT_SIGBUS; |
| else |
| result = __dax_pmd_fault(vma, addr, pmd, flags, |
| ext4_get_block_dax, ext4_end_io_unwritten); |
| |
| if (write) { |
| if (!IS_ERR(handle)) |
| ext4_journal_stop(handle); |
| up_read(&EXT4_I(inode)->i_mmap_sem); |
| sb_end_pagefault(sb); |
| } else |
| up_read(&EXT4_I(inode)->i_mmap_sem); |
| |
| return result; |
| } |
| |
| static int ext4_dax_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
| { |
| int err; |
| struct inode *inode = file_inode(vma->vm_file); |
| |
| sb_start_pagefault(inode->i_sb); |
| file_update_time(vma->vm_file); |
| down_read(&EXT4_I(inode)->i_mmap_sem); |
| err = __dax_mkwrite(vma, vmf, ext4_get_block_dax, |
| ext4_end_io_unwritten); |
| up_read(&EXT4_I(inode)->i_mmap_sem); |
| sb_end_pagefault(inode->i_sb); |
| |
| return err; |
| } |
| |
| /* |
| * Handle write fault for VM_MIXEDMAP mappings. Similarly to ext4_dax_mkwrite() |
| * handler we check for races agaist truncate. Note that since we cycle through |
| * i_mmap_sem, we are sure that also any hole punching that began before we |
| * were called is finished by now and so if it included part of the file we |
| * are working on, our pte will get unmapped and the check for pte_same() in |
| * wp_pfn_shared() fails. Thus fault gets retried and things work out as |
| * desired. |
| */ |
| static int ext4_dax_pfn_mkwrite(struct vm_area_struct *vma, |
| struct vm_fault *vmf) |
| { |
| struct inode *inode = file_inode(vma->vm_file); |
| struct super_block *sb = inode->i_sb; |
| int ret = VM_FAULT_NOPAGE; |
| loff_t size; |
| |
| sb_start_pagefault(sb); |
| file_update_time(vma->vm_file); |
| down_read(&EXT4_I(inode)->i_mmap_sem); |
| size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT; |
| if (vmf->pgoff >= size) |
| ret = VM_FAULT_SIGBUS; |
| up_read(&EXT4_I(inode)->i_mmap_sem); |
| sb_end_pagefault(sb); |
| |
| return ret; |
| } |
| |
| static const struct vm_operations_struct ext4_dax_vm_ops = { |
| .fault = ext4_dax_fault, |
| .pmd_fault = ext4_dax_pmd_fault, |
| .page_mkwrite = ext4_dax_mkwrite, |
| .pfn_mkwrite = ext4_dax_pfn_mkwrite, |
| }; |
| #else |
| #define ext4_dax_vm_ops ext4_file_vm_ops |
| #endif |
| |
| static const struct vm_operations_struct ext4_file_vm_ops = { |
| .fault = ext4_filemap_fault, |
| .map_pages = filemap_map_pages, |
| .page_mkwrite = ext4_page_mkwrite, |
| }; |
| |
| static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma) |
| { |
| struct inode *inode = file->f_mapping->host; |
| |
| if (ext4_encrypted_inode(inode)) { |
| int err = ext4_get_encryption_info(inode); |
| if (err) |
| return 0; |
| if (ext4_encryption_info(inode) == NULL) |
| return -ENOKEY; |
| } |
| file_accessed(file); |
| if (IS_DAX(file_inode(file))) { |
| vma->vm_ops = &ext4_dax_vm_ops; |
| vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE; |
| } else { |
| vma->vm_ops = &ext4_file_vm_ops; |
| } |
| return 0; |
| } |
| |
| static int ext4_file_open(struct inode * inode, struct file * filp) |
| { |
| struct super_block *sb = inode->i_sb; |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| struct vfsmount *mnt = filp->f_path.mnt; |
| struct path path; |
| char buf[64], *cp; |
| int ret; |
| |
| if (unlikely(!(sbi->s_mount_flags & EXT4_MF_MNTDIR_SAMPLED) && |
| !(sb->s_flags & MS_RDONLY))) { |
| sbi->s_mount_flags |= EXT4_MF_MNTDIR_SAMPLED; |
| /* |
| * Sample where the filesystem has been mounted and |
| * store it in the superblock for sysadmin convenience |
| * when trying to sort through large numbers of block |
| * devices or filesystem images. |
| */ |
| memset(buf, 0, sizeof(buf)); |
| path.mnt = mnt; |
| path.dentry = mnt->mnt_root; |
| cp = d_path(&path, buf, sizeof(buf)); |
| if (!IS_ERR(cp)) { |
| handle_t *handle; |
| int err; |
| |
| handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1); |
| if (IS_ERR(handle)) |
| return PTR_ERR(handle); |
| BUFFER_TRACE(sbi->s_sbh, "get_write_access"); |
| err = ext4_journal_get_write_access(handle, sbi->s_sbh); |
| if (err) { |
| ext4_journal_stop(handle); |
| return err; |
| } |
| strlcpy(sbi->s_es->s_last_mounted, cp, |
| sizeof(sbi->s_es->s_last_mounted)); |
| ext4_handle_dirty_super(handle, sb); |
| ext4_journal_stop(handle); |
| } |
| } |
| if (ext4_encrypted_inode(inode)) { |
| ret = ext4_get_encryption_info(inode); |
| if (ret) |
| return -EACCES; |
| if (ext4_encryption_info(inode) == NULL) |
| return -ENOKEY; |
| } |
| /* |
| * Set up the jbd2_inode if we are opening the inode for |
| * writing and the journal is present |
| */ |
| if (filp->f_mode & FMODE_WRITE) { |
| ret = ext4_inode_attach_jinode(inode); |
| if (ret < 0) |
| return ret; |
| } |
| return dquot_file_open(inode, filp); |
| } |
| |
| /* |
| * Here we use ext4_map_blocks() to get a block mapping for a extent-based |
| * file rather than ext4_ext_walk_space() because we can introduce |
| * SEEK_DATA/SEEK_HOLE for block-mapped and extent-mapped file at the same |
| * function. When extent status tree has been fully implemented, it will |
| * track all extent status for a file and we can directly use it to |
| * retrieve the offset for SEEK_DATA/SEEK_HOLE. |
| */ |
| |
| /* |
| * When we retrieve the offset for SEEK_DATA/SEEK_HOLE, we would need to |
| * lookup page cache to check whether or not there has some data between |
| * [startoff, endoff] because, if this range contains an unwritten extent, |
| * we determine this extent as a data or a hole according to whether the |
| * page cache has data or not. |
| */ |
| static int ext4_find_unwritten_pgoff(struct inode *inode, |
| int whence, |
| struct ext4_map_blocks *map, |
| loff_t *offset) |
| { |
| struct pagevec pvec; |
| unsigned int blkbits; |
| pgoff_t index; |
| pgoff_t end; |
| loff_t endoff; |
| loff_t startoff; |
| loff_t lastoff; |
| int found = 0; |
| |
| blkbits = inode->i_sb->s_blocksize_bits; |
| startoff = *offset; |
| lastoff = startoff; |
| endoff = (loff_t)(map->m_lblk + map->m_len) << blkbits; |
| |
| index = startoff >> PAGE_CACHE_SHIFT; |
| end = endoff >> PAGE_CACHE_SHIFT; |
| |
| pagevec_init(&pvec, 0); |
| do { |
| int i, num; |
| unsigned long nr_pages; |
| |
| num = min_t(pgoff_t, end - index, PAGEVEC_SIZE - 1) + 1; |
| nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index, |
| (pgoff_t)num); |
| if (nr_pages == 0) |
| break; |
| |
| for (i = 0; i < nr_pages; i++) { |
| struct page *page = pvec.pages[i]; |
| struct buffer_head *bh, *head; |
| |
| /* |
| * If current offset is smaller than the page offset, |
| * there is a hole at this offset. |
| */ |
| if (whence == SEEK_HOLE && lastoff < endoff && |
| lastoff < page_offset(pvec.pages[i])) { |
| found = 1; |
| *offset = lastoff; |
| goto out; |
| } |
| |
| if (page->index > end) |
| goto out; |
| |
| lock_page(page); |
| |
| if (unlikely(page->mapping != inode->i_mapping)) { |
| unlock_page(page); |
| continue; |
| } |
| |
| if (!page_has_buffers(page)) { |
| unlock_page(page); |
| continue; |
| } |
| |
| if (page_has_buffers(page)) { |
| lastoff = page_offset(page); |
| bh = head = page_buffers(page); |
| do { |
| if (lastoff + bh->b_size <= startoff) |
| goto next; |
| if (buffer_uptodate(bh) || |
| buffer_unwritten(bh)) { |
| if (whence == SEEK_DATA) |
| found = 1; |
| } else { |
| if (whence == SEEK_HOLE) |
| found = 1; |
| } |
| if (found) { |
| *offset = max_t(loff_t, |
| startoff, lastoff); |
| unlock_page(page); |
| goto out; |
| } |
| next: |
| lastoff += bh->b_size; |
| bh = bh->b_this_page; |
| } while (bh != head); |
| } |
| |
| lastoff = page_offset(page) + PAGE_SIZE; |
| unlock_page(page); |
| } |
| |
| /* The no. of pages is less than our desired, we are done. */ |
| if (nr_pages < num) |
| break; |
| |
| index = pvec.pages[i - 1]->index + 1; |
| pagevec_release(&pvec); |
| } while (index <= end); |
| |
| if (whence == SEEK_HOLE && lastoff < endoff) { |
| found = 1; |
| *offset = lastoff; |
| } |
| out: |
| pagevec_release(&pvec); |
| return found; |
| } |
| |
| /* |
| * ext4_seek_data() retrieves the offset for SEEK_DATA. |
| */ |
| static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize) |
| { |
| struct inode *inode = file->f_mapping->host; |
| struct ext4_map_blocks map; |
| struct extent_status es; |
| ext4_lblk_t start, last, end; |
| loff_t dataoff, isize; |
| int blkbits; |
| int ret = 0; |
| |
| mutex_lock(&inode->i_mutex); |
| |
| isize = i_size_read(inode); |
| if (offset < 0 || offset >= isize) { |
| mutex_unlock(&inode->i_mutex); |
| return -ENXIO; |
| } |
| |
| blkbits = inode->i_sb->s_blocksize_bits; |
| start = offset >> blkbits; |
| last = start; |
| end = isize >> blkbits; |
| dataoff = offset; |
| |
| do { |
| map.m_lblk = last; |
| map.m_len = end - last + 1; |
| ret = ext4_map_blocks(NULL, inode, &map, 0); |
| if (ret > 0 && !(map.m_flags & EXT4_MAP_UNWRITTEN)) { |
| if (last != start) |
| dataoff = (loff_t)last << blkbits; |
| break; |
| } |
| |
| /* |
| * If there is a delay extent at this offset, |
| * it will be as a data. |
| */ |
| ext4_es_find_delayed_extent_range(inode, last, last, &es); |
| if (es.es_len != 0 && in_range(last, es.es_lblk, es.es_len)) { |
| if (last != start) |
| dataoff = (loff_t)last << blkbits; |
| break; |
| } |
| |
| /* |
| * If there is a unwritten extent at this offset, |
| * it will be as a data or a hole according to page |
| * cache that has data or not. |
| */ |
| if (map.m_flags & EXT4_MAP_UNWRITTEN) { |
| int unwritten; |
| unwritten = ext4_find_unwritten_pgoff(inode, SEEK_DATA, |
| &map, &dataoff); |
| if (unwritten) |
| break; |
| } |
| |
| last++; |
| dataoff = (loff_t)last << blkbits; |
| } while (last <= end); |
| |
| mutex_unlock(&inode->i_mutex); |
| |
| if (dataoff > isize) |
| return -ENXIO; |
| |
| return vfs_setpos(file, dataoff, maxsize); |
| } |
| |
| /* |
| * ext4_seek_hole() retrieves the offset for SEEK_HOLE. |
| */ |
| static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize) |
| { |
| struct inode *inode = file->f_mapping->host; |
| struct ext4_map_blocks map; |
| struct extent_status es; |
| ext4_lblk_t start, last, end; |
| loff_t holeoff, isize; |
| int blkbits; |
| int ret = 0; |
| |
| mutex_lock(&inode->i_mutex); |
| |
| isize = i_size_read(inode); |
| if (offset < 0 || offset >= isize) { |
| mutex_unlock(&inode->i_mutex); |
| return -ENXIO; |
| } |
| |
| blkbits = inode->i_sb->s_blocksize_bits; |
| start = offset >> blkbits; |
| last = start; |
| end = isize >> blkbits; |
| holeoff = offset; |
| |
| do { |
| map.m_lblk = last; |
| map.m_len = end - last + 1; |
| ret = ext4_map_blocks(NULL, inode, &map, 0); |
| if (ret > 0 && !(map.m_flags & EXT4_MAP_UNWRITTEN)) { |
| last += ret; |
| holeoff = (loff_t)last << blkbits; |
| continue; |
| } |
| |
| /* |
| * If there is a delay extent at this offset, |
| * we will skip this extent. |
| */ |
| ext4_es_find_delayed_extent_range(inode, last, last, &es); |
| if (es.es_len != 0 && in_range(last, es.es_lblk, es.es_len)) { |
| last = es.es_lblk + es.es_len; |
| holeoff = (loff_t)last << blkbits; |
| continue; |
| } |
| |
| /* |
| * If there is a unwritten extent at this offset, |
| * it will be as a data or a hole according to page |
| * cache that has data or not. |
| */ |
| if (map.m_flags & EXT4_MAP_UNWRITTEN) { |
| int unwritten; |
| unwritten = ext4_find_unwritten_pgoff(inode, SEEK_HOLE, |
| &map, &holeoff); |
| if (!unwritten) { |
| last += ret; |
| holeoff = (loff_t)last << blkbits; |
| continue; |
| } |
| } |
| |
| /* find a hole */ |
| break; |
| } while (last <= end); |
| |
| mutex_unlock(&inode->i_mutex); |
| |
| if (holeoff > isize) |
| holeoff = isize; |
| |
| return vfs_setpos(file, holeoff, maxsize); |
| } |
| |
| /* |
| * ext4_llseek() handles both block-mapped and extent-mapped maxbytes values |
| * by calling generic_file_llseek_size() with the appropriate maxbytes |
| * value for each. |
| */ |
| loff_t ext4_llseek(struct file *file, loff_t offset, int whence) |
| { |
| struct inode *inode = file->f_mapping->host; |
| loff_t maxbytes; |
| |
| if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
| maxbytes = EXT4_SB(inode->i_sb)->s_bitmap_maxbytes; |
| else |
| maxbytes = inode->i_sb->s_maxbytes; |
| |
| switch (whence) { |
| case SEEK_SET: |
| case SEEK_CUR: |
| case SEEK_END: |
| return generic_file_llseek_size(file, offset, whence, |
| maxbytes, i_size_read(inode)); |
| case SEEK_DATA: |
| return ext4_seek_data(file, offset, maxbytes); |
| case SEEK_HOLE: |
| return ext4_seek_hole(file, offset, maxbytes); |
| } |
| |
| return -EINVAL; |
| } |
| |
| const struct file_operations ext4_file_operations = { |
| .llseek = ext4_llseek, |
| .read_iter = generic_file_read_iter, |
| .write_iter = ext4_file_write_iter, |
| .unlocked_ioctl = ext4_ioctl, |
| #ifdef CONFIG_COMPAT |
| .compat_ioctl = ext4_compat_ioctl, |
| #endif |
| .mmap = ext4_file_mmap, |
| .open = ext4_file_open, |
| .release = ext4_release_file, |
| .fsync = ext4_sync_file, |
| .splice_read = generic_file_splice_read, |
| .splice_write = iter_file_splice_write, |
| .fallocate = ext4_fallocate, |
| }; |
| |
| const struct inode_operations ext4_file_inode_operations = { |
| .setattr = ext4_setattr, |
| .getattr = ext4_getattr, |
| .setxattr = generic_setxattr, |
| .getxattr = generic_getxattr, |
| .listxattr = ext4_listxattr, |
| .removexattr = generic_removexattr, |
| .get_acl = ext4_get_acl, |
| .set_acl = ext4_set_acl, |
| .fiemap = ext4_fiemap, |
| }; |
| |