/* * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. * * This copyrighted material is made available to anyone wishing to use, * modify, copy, or redistribute it subject to the terms and conditions * of the GNU General Public License version 2. */ #include <linux/sched.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/completion.h> #include <linux/buffer_head.h> #include <linux/pagemap.h> #include <linux/uio.h> #include <linux/blkdev.h> #include <linux/mm.h> #include <linux/smp_lock.h> #include <linux/fs.h> #include <linux/gfs2_ondisk.h> #include <linux/ext2_fs.h> #include <linux/crc32.h> #include <linux/lm_interface.h> #include <asm/uaccess.h> #include "gfs2.h" #include "incore.h" #include "bmap.h" #include "dir.h" #include "glock.h" #include "glops.h" #include "inode.h" #include "lm.h" #include "log.h" #include "meta_io.h" #include "ops_file.h" #include "ops_vm.h" #include "quota.h" #include "rgrp.h" #include "trans.h" #include "util.h" #include "eaops.h" /* For regular, non-NFS */ struct filldir_reg { struct gfs2_sbd *fdr_sbd; int fdr_prefetch; filldir_t fdr_filldir; void *fdr_opaque; }; /* * Most fields left uninitialised to catch anybody who tries to * use them. f_flags set to prevent file_accessed() from touching * any other part of this. Its use is purely as a flag so that we * know (in readpage()) whether or not do to locking. */ struct file gfs2_internal_file_sentinel = { .f_flags = O_NOATIME|O_RDONLY, }; static int gfs2_read_actor(read_descriptor_t *desc, struct page *page, unsigned long offset, unsigned long size) { char *kaddr; unsigned long count = desc->count; if (size > count) size = count; kaddr = kmap(page); memcpy(desc->arg.buf, kaddr + offset, size); kunmap(page); desc->count = count - size; desc->written += size; desc->arg.buf += size; return size; } int gfs2_internal_read(struct gfs2_inode *ip, struct file_ra_state *ra_state, char *buf, loff_t *pos, unsigned size) { struct inode *inode = &ip->i_inode; read_descriptor_t desc; desc.written = 0; desc.arg.buf = buf; desc.count = size; desc.error = 0; do_generic_mapping_read(inode->i_mapping, ra_state, &gfs2_internal_file_sentinel, pos, &desc, gfs2_read_actor); return desc.written ? desc.written : desc.error; } /** * gfs2_llseek - seek to a location in a file * @file: the file * @offset: the offset * @origin: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END) * * SEEK_END requires the glock for the file because it references the * file's size. * * Returns: The new offset, or errno */ static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin) { struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); struct gfs2_holder i_gh; loff_t error; if (origin == 2) { error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh); if (!error) { error = remote_llseek(file, offset, origin); gfs2_glock_dq_uninit(&i_gh); } } else error = remote_llseek(file, offset, origin); return error; } /** * filldir_func - Report a directory entry to the caller of gfs2_dir_read() * @opaque: opaque data used by the function * @name: the name of the directory entry * @length: the length of the name * @offset: the entry's offset in the directory * @inum: the inode number the entry points to * @type: the type of inode the entry points to * * Returns: 0 on success, 1 if buffer full */ static int filldir_func(void *opaque, const char *name, unsigned int length, u64 offset, struct gfs2_inum *inum, unsigned int type) { struct filldir_reg *fdr = (struct filldir_reg *)opaque; struct gfs2_sbd *sdp = fdr->fdr_sbd; int error; error = fdr->fdr_filldir(fdr->fdr_opaque, name, length, offset, inum->no_addr, type); if (error) return 1; if (fdr->fdr_prefetch && !(length == 1 && *name == '.')) { gfs2_glock_prefetch_num(sdp, inum->no_addr, &gfs2_inode_glops, LM_ST_SHARED, LM_FLAG_TRY | LM_FLAG_ANY); gfs2_glock_prefetch_num(sdp, inum->no_addr, &gfs2_iopen_glops, LM_ST_SHARED, LM_FLAG_TRY); } return 0; } /** * gfs2_readdir - Read directory entries from a directory * @file: The directory to read from * @dirent: Buffer for dirents * @filldir: Function used to do the copying * * Returns: errno */ static int gfs2_readdir(struct file *file, void *dirent, filldir_t filldir) { struct inode *dir = file->f_mapping->host; struct gfs2_inode *dip = GFS2_I(dir); struct filldir_reg fdr; struct gfs2_holder d_gh; u64 offset = file->f_pos; int error; fdr.fdr_sbd = GFS2_SB(dir); fdr.fdr_prefetch = 1; fdr.fdr_filldir = filldir; fdr.fdr_opaque = dirent; gfs2_holder_init(dip->i_gl, LM_ST_SHARED, GL_ATIME, &d_gh); error = gfs2_glock_nq_atime(&d_gh); if (error) { gfs2_holder_uninit(&d_gh); return error; } error = gfs2_dir_read(dir, &offset, &fdr, filldir_func); gfs2_glock_dq_uninit(&d_gh); file->f_pos = offset; return error; } /** * fsflags_cvt * @table: A table of 32 u32 flags * @val: a 32 bit value to convert * * This function can be used to convert between fsflags values and * GFS2's own flags values. * * Returns: the converted flags */ static u32 fsflags_cvt(const u32 *table, u32 val) { u32 res = 0; while(val) { if (val & 1) res |= *table; table++; val >>= 1; } return res; } static const u32 fsflags_to_gfs2[32] = { [3] = GFS2_DIF_SYNC, [4] = GFS2_DIF_IMMUTABLE, [5] = GFS2_DIF_APPENDONLY, [7] = GFS2_DIF_NOATIME, [12] = GFS2_DIF_EXHASH, [14] = GFS2_DIF_JDATA, [20] = GFS2_DIF_DIRECTIO, }; static const u32 gfs2_to_fsflags[32] = { [gfs2fl_Sync] = FS_SYNC_FL, [gfs2fl_Immutable] = FS_IMMUTABLE_FL, [gfs2fl_AppendOnly] = FS_APPEND_FL, [gfs2fl_NoAtime] = FS_NOATIME_FL, [gfs2fl_ExHash] = FS_INDEX_FL, [gfs2fl_Jdata] = FS_JOURNAL_DATA_FL, [gfs2fl_Directio] = FS_DIRECTIO_FL, [gfs2fl_InheritDirectio] = FS_DIRECTIO_FL, [gfs2fl_InheritJdata] = FS_JOURNAL_DATA_FL, }; static int gfs2_get_flags(struct file *filp, u32 __user *ptr) { struct inode *inode = filp->f_dentry->d_inode; struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_holder gh; int error; u32 fsflags; gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh); error = gfs2_glock_nq_m_atime(1, &gh); if (error) return error; fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_di.di_flags); if (put_user(fsflags, ptr)) error = -EFAULT; gfs2_glock_dq_m(1, &gh); gfs2_holder_uninit(&gh); return error; } /* Flags that can be set by user space */ #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \ GFS2_DIF_DIRECTIO| \ GFS2_DIF_IMMUTABLE| \ GFS2_DIF_APPENDONLY| \ GFS2_DIF_NOATIME| \ GFS2_DIF_SYNC| \ GFS2_DIF_SYSTEM| \ GFS2_DIF_INHERIT_DIRECTIO| \ GFS2_DIF_INHERIT_JDATA) /** * gfs2_set_flags - set flags on an inode * @inode: The inode * @flags: The flags to set * @mask: Indicates which flags are valid * */ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask) { struct inode *inode = filp->f_dentry->d_inode; struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_sbd *sdp = GFS2_SB(inode); struct buffer_head *bh; struct gfs2_holder gh; int error; u32 new_flags, flags; error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); if (error) return error; flags = ip->i_di.di_flags; new_flags = (flags & ~mask) | (reqflags & mask); if ((new_flags ^ flags) == 0) goto out; if (S_ISDIR(inode->i_mode)) { if ((new_flags ^ flags) & GFS2_DIF_JDATA) new_flags ^= (GFS2_DIF_JDATA|GFS2_DIF_INHERIT_JDATA); if ((new_flags ^ flags) & GFS2_DIF_DIRECTIO) new_flags ^= (GFS2_DIF_DIRECTIO|GFS2_DIF_INHERIT_DIRECTIO); } error = -EINVAL; if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET) goto out; error = -EPERM; if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE)) goto out; if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY)) goto out; if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) && !capable(CAP_LINUX_IMMUTABLE)) goto out; if (!IS_IMMUTABLE(inode)) { error = permission(inode, MAY_WRITE, NULL); if (error) goto out; } error = gfs2_trans_begin(sdp, RES_DINODE, 0); if (error) goto out; error = gfs2_meta_inode_buffer(ip, &bh); if (error) goto out_trans_end; gfs2_trans_add_bh(ip->i_gl, bh, 1); ip->i_di.di_flags = new_flags; gfs2_dinode_out(&ip->i_di, bh->b_data); brelse(bh); out_trans_end: gfs2_trans_end(sdp); out: gfs2_glock_dq_uninit(&gh); return error; } static int gfs2_set_flags(struct file *filp, u32 __user *ptr) { u32 fsflags, gfsflags; if (get_user(fsflags, ptr)) return -EFAULT; gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags); return do_gfs2_set_flags(filp, gfsflags, ~0); } static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { switch(cmd) { case FS_IOC_GETFLAGS: return gfs2_get_flags(filp, (u32 __user *)arg); case FS_IOC_SETFLAGS: return gfs2_set_flags(filp, (u32 __user *)arg); } return -ENOTTY; } /** * gfs2_mmap - * @file: The file to map * @vma: The VMA which described the mapping * * Returns: 0 or error code */ static int gfs2_mmap(struct file *file, struct vm_area_struct *vma) { struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); struct gfs2_holder i_gh; int error; gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &i_gh); error = gfs2_glock_nq_atime(&i_gh); if (error) { gfs2_holder_uninit(&i_gh); return error; } /* This is VM_MAYWRITE instead of VM_WRITE because a call to mprotect() can turn on VM_WRITE later. */ if ((vma->vm_flags & (VM_MAYSHARE | VM_MAYWRITE)) == (VM_MAYSHARE | VM_MAYWRITE)) vma->vm_ops = &gfs2_vm_ops_sharewrite; else vma->vm_ops = &gfs2_vm_ops_private; gfs2_glock_dq_uninit(&i_gh); return error; } /** * gfs2_open - open a file * @inode: the inode to open * @file: the struct file for this opening * * Returns: errno */ static int gfs2_open(struct inode *inode, struct file *file) { struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_holder i_gh; struct gfs2_file *fp; int error; fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL); if (!fp) return -ENOMEM; mutex_init(&fp->f_fl_mutex); gfs2_assert_warn(GFS2_SB(inode), !file->private_data); file->private_data = fp; if (S_ISREG(ip->i_di.di_mode)) { error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh); if (error) goto fail; if (!(file->f_flags & O_LARGEFILE) && ip->i_di.di_size > MAX_NON_LFS) { error = -EFBIG; goto fail_gunlock; } /* Listen to the Direct I/O flag */ if (ip->i_di.di_flags & GFS2_DIF_DIRECTIO) file->f_flags |= O_DIRECT; gfs2_glock_dq_uninit(&i_gh); } return 0; fail_gunlock: gfs2_glock_dq_uninit(&i_gh); fail: file->private_data = NULL; kfree(fp); return error; } /** * gfs2_close - called to close a struct file * @inode: the inode the struct file belongs to * @file: the struct file being closed * * Returns: errno */ static int gfs2_close(struct inode *inode, struct file *file) { struct gfs2_sbd *sdp = inode->i_sb->s_fs_info; struct gfs2_file *fp; fp = file->private_data; file->private_data = NULL; if (gfs2_assert_warn(sdp, fp)) return -EIO; kfree(fp); return 0; } /** * gfs2_fsync - sync the dirty data for a file (across the cluster) * @file: the file that points to the dentry (we ignore this) * @dentry: the dentry that points to the inode to sync * * Returns: errno */ static int gfs2_fsync(struct file *file, struct dentry *dentry, int datasync) { struct gfs2_inode *ip = GFS2_I(dentry->d_inode); gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl); return 0; } /** * gfs2_lock - acquire/release a posix lock on a file * @file: the file pointer * @cmd: either modify or retrieve lock state, possibly wait * @fl: type and range of lock * * Returns: errno */ static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl) { struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host); struct lm_lockname name = { .ln_number = ip->i_num.no_addr, .ln_type = LM_TYPE_PLOCK }; if (!(fl->fl_flags & FL_POSIX)) return -ENOLCK; if ((ip->i_di.di_mode & (S_ISGID | S_IXGRP)) == S_ISGID) return -ENOLCK; if (sdp->sd_args.ar_localflocks) { if (IS_GETLK(cmd)) { struct file_lock tmp; int ret; ret = posix_test_lock(file, fl, &tmp); fl->fl_type = F_UNLCK; if (ret) memcpy(fl, &tmp, sizeof(struct file_lock)); return 0; } else { return posix_lock_file_wait(file, fl); } } if (IS_GETLK(cmd)) return gfs2_lm_plock_get(sdp, &name, file, fl); else if (fl->fl_type == F_UNLCK) return gfs2_lm_punlock(sdp, &name, file, fl); else return gfs2_lm_plock(sdp, &name, file, cmd, fl); } static int do_flock(struct file *file, int cmd, struct file_lock *fl) { struct gfs2_file *fp = file->private_data; struct gfs2_holder *fl_gh = &fp->f_fl_gh; struct gfs2_inode *ip = GFS2_I(file->f_dentry->d_inode); struct gfs2_glock *gl; unsigned int state; int flags; int error = 0; state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED; flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE; mutex_lock(&fp->f_fl_mutex); gl = fl_gh->gh_gl; if (gl) { if (fl_gh->gh_state == state) goto out; gfs2_glock_hold(gl); flock_lock_file_wait(file, &(struct file_lock){.fl_type = F_UNLCK}); gfs2_glock_dq_uninit(fl_gh); } else { error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_num.no_addr, &gfs2_flock_glops, CREATE, &gl); if (error) goto out; } gfs2_holder_init(gl, state, flags, fl_gh); gfs2_glock_put(gl); error = gfs2_glock_nq(fl_gh); if (error) { gfs2_holder_uninit(fl_gh); if (error == GLR_TRYFAILED) error = -EAGAIN; } else { error = flock_lock_file_wait(file, fl); gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error); } out: mutex_unlock(&fp->f_fl_mutex); return error; } static void do_unflock(struct file *file, struct file_lock *fl) { struct gfs2_file *fp = file->private_data; struct gfs2_holder *fl_gh = &fp->f_fl_gh; mutex_lock(&fp->f_fl_mutex); flock_lock_file_wait(file, fl); if (fl_gh->gh_gl) gfs2_glock_dq_uninit(fl_gh); mutex_unlock(&fp->f_fl_mutex); } /** * gfs2_flock - acquire/release a flock lock on a file * @file: the file pointer * @cmd: either modify or retrieve lock state, possibly wait * @fl: type and range of lock * * Returns: errno */ static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl) { struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host); if (!(fl->fl_flags & FL_FLOCK)) return -ENOLCK; if ((ip->i_di.di_mode & (S_ISGID | S_IXGRP)) == S_ISGID) return -ENOLCK; if (sdp->sd_args.ar_localflocks) return flock_lock_file_wait(file, fl); if (fl->fl_type == F_UNLCK) { do_unflock(file, fl); return 0; } else { return do_flock(file, cmd, fl); } } const struct file_operations gfs2_file_fops = { .llseek = gfs2_llseek, .read = do_sync_read, .aio_read = generic_file_aio_read, .write = do_sync_write, .aio_write = generic_file_aio_write, .unlocked_ioctl = gfs2_ioctl, .mmap = gfs2_mmap, .open = gfs2_open, .release = gfs2_close, .fsync = gfs2_fsync, .lock = gfs2_lock, .sendfile = generic_file_sendfile, .flock = gfs2_flock, .splice_read = generic_file_splice_read, .splice_write = generic_file_splice_write, }; const struct file_operations gfs2_dir_fops = { .readdir = gfs2_readdir, .unlocked_ioctl = gfs2_ioctl, .open = gfs2_open, .release = gfs2_close, .fsync = gfs2_fsync, .lock = gfs2_lock, .flock = gfs2_flock, };