/* * linux/fs/ext2/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 * * ext2 fs regular file handling primitives * * 64-bit file support on 64-bit platforms by Jakub Jelinek * (jj@sunsite.ms.mff.cuni.cz) */ #include <linux/fs.h> 22 #include <linux/ext2_fs.h> #include <linux/sched.h> static loff_t ext2_file_lseek(struct file *, loff_t, int); static int ext2_open_file (struct inode *, struct file *); 27 #define EXT2_MAX_SIZE(bits) \ 29 (((EXT2_NDIR_BLOCKS + (1LL << (bits - 2)) + \ (1LL << (bits - 2)) * (1LL << (bits - 2)) + \ 31 (1LL << (bits - 2)) * (1LL << (bits - 2)) * (1LL << (bits - 2))) * \ (1LL << bits)) - 1) 34 static long long ext2_max_sizes[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, EXT2_MAX_SIZE(10), EXT2_MAX_SIZE(11), EXT2_MAX_SIZE(12), EXT2_MAX_SIZE(13) }; 38 /* 40 * Make sure the offset never goes beyond the 32-bit mark.. */ static loff_t ext2_file_lseek( 43 struct file *file, 44 loff_t offset, 45 int origin) { 47 struct inode *inode = file->f_dentry->d_inode; switch (origin) { case 2: offset += inode->i_size; break; case 1: offset += file->f_pos; } 56 if (offset<0) return -EINVAL; if (((unsigned long long) offset >> 32) != 0) { if (offset > ext2_max_sizes[EXT2_BLOCK_SIZE_BITS(inode->i_sb)]) return -EINVAL; } if (offset != file->f_pos) { 63 file->f_pos = offset; 64 file->f_reada = 0; file->f_version = ++event; } 67 return offset; } /* * Called when an inode is released. Note that this is different * from ext2_file_open: open gets called at every open, but release * gets called only when /all/ the files are closed. 74 */ static int ext2_release_file (struct inode * inode, struct file * filp) 76 { if (filp->f_mode & FMODE_WRITE) ext2_discard_prealloc (inode); return 0; 80 } 82 /* * Called when an inode is about to be open. 84 * We use this to disallow opening RW large files on 32bit systems if * the caller didn't specify O_LARGEFILE. On 64bit systems we force * on this flag in sys_open. 87 */ static int ext2_open_file (struct inode * inode, struct file * filp) { if (!(filp->f_flags & O_LARGEFILE) && inode->i_size > 0x7FFFFFFFLL) 92 return -EFBIG; 93 return 0; } /* 97 * We have mostly NULL's here: the current defaults are ok for * the ext2 filesystem. */ struct file_operations ext2_file_operations = { llseek: ext2_file_lseek, read: generic_file_read, write: generic_file_write, ioctl: ext2_ioctl, mmap: generic_file_mmap, 106 open: ext2_open_file, release: ext2_release_file, fsync: ext2_sync_file, }; struct inode_operations ext2_file_inode_operations = { 112 truncate: ext2_truncate, };