diff options
Diffstat (limited to 'fs/gfs2/ops_file.c')
| -rw-r--r-- | fs/gfs2/ops_file.c | 1597 |
1 files changed, 1597 insertions, 0 deletions
diff --git a/fs/gfs2/ops_file.c b/fs/gfs2/ops_file.c new file mode 100644 index 000000000000..1e6f51b74f44 --- /dev/null +++ b/fs/gfs2/ops_file.c @@ -0,0 +1,1597 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2005 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 v.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/gfs2_ioctl.h> +#include <asm/semaphore.h> +#include <asm/uaccess.h> + +#include "gfs2.h" +#include "bmap.h" +#include "dir.h" +#include "glock.h" +#include "glops.h" +#include "inode.h" +#include "jdata.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" + +/* "bad" is for NFS support */ +struct filldir_bad_entry { + char *fbe_name; + unsigned int fbe_length; + uint64_t fbe_offset; + struct gfs2_inum fbe_inum; + unsigned int fbe_type; +}; + +struct filldir_bad { + struct gfs2_sbd *fdb_sbd; + + struct filldir_bad_entry *fdb_entry; + unsigned int fdb_entry_num; + unsigned int fdb_entry_off; + + char *fdb_name; + unsigned int fdb_name_size; + unsigned int fdb_name_off; +}; + +/* For regular, non-NFS */ +struct filldir_reg { + struct gfs2_sbd *fdr_sbd; + int fdr_prefetch; + + filldir_t fdr_filldir; + void *fdr_opaque; +}; + +typedef ssize_t(*do_rw_t) (struct file *file, + char __user *buf, + size_t size, loff_t *offset, + unsigned int num_gh, struct gfs2_holder *ghs); + +/** + * 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 = get_v2ip(file->f_mapping->host); + struct gfs2_holder i_gh; + loff_t error; + + atomic_inc(&ip->i_sbd->sd_ops_file); + + 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; +} + +static inline unsigned int vma2state(struct vm_area_struct *vma) +{ + if ((vma->vm_flags & (VM_MAYWRITE | VM_MAYSHARE)) == + (VM_MAYWRITE | VM_MAYSHARE)) + return LM_ST_EXCLUSIVE; + return LM_ST_SHARED; +} + +static ssize_t walk_vm_hard(struct file *file, const char __user *buf, size_t size, + loff_t *offset, do_rw_t operation) +{ + struct gfs2_holder *ghs; + unsigned int num_gh = 0; + ssize_t count; + struct super_block *sb = file->f_dentry->d_inode->i_sb; + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + unsigned long start = (unsigned long)buf; + unsigned long end = start + size; + int dumping = (current->flags & PF_DUMPCORE); + unsigned int x = 0; + + for (vma = find_vma(mm, start); vma; vma = vma->vm_next) { + if (end <= vma->vm_start) + break; + if (vma->vm_file && + vma->vm_file->f_dentry->d_inode->i_sb == sb) { + num_gh++; + } + } + + ghs = kcalloc((num_gh + 1), sizeof(struct gfs2_holder), GFP_KERNEL); + if (!ghs) { + if (!dumping) + up_read(&mm->mmap_sem); + return -ENOMEM; + } + + for (vma = find_vma(mm, start); vma; vma = vma->vm_next) { + if (end <= vma->vm_start) + break; + if (vma->vm_file) { + struct inode *inode = vma->vm_file->f_dentry->d_inode; + if (inode->i_sb == sb) + gfs2_holder_init(get_v2ip(inode)->i_gl, + vma2state(vma), 0, &ghs[x++]); + } + } + + if (!dumping) + up_read(&mm->mmap_sem); + + gfs2_assert(get_v2sdp(sb), x == num_gh); + + count = operation(file, buf, size, offset, num_gh, ghs); + + while (num_gh--) + gfs2_holder_uninit(&ghs[num_gh]); + kfree(ghs); + + return count; +} + +/** + * walk_vm - Walk the vmas associated with a buffer for read or write. + * If any of them are gfs2, pass the gfs2 inode down to the read/write + * worker function so that locks can be acquired in the correct order. + * @file: The file to read/write from/to + * @buf: The buffer to copy to/from + * @size: The amount of data requested + * @offset: The current file offset + * @operation: The read or write worker function + * + * Outputs: Offset - updated according to number of bytes written + * + * Returns: The number of bytes written, errno on failure + */ + +static ssize_t walk_vm(struct file *file, const char __user *buf, size_t size, + loff_t *offset, do_rw_t operation) +{ + struct gfs2_holder gh; + + if (current->mm) { + struct super_block *sb = file->f_dentry->d_inode->i_sb; + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + unsigned long start = (unsigned long)buf; + unsigned long end = start + size; + int dumping = (current->flags & PF_DUMPCORE); + + if (!dumping) + down_read(&mm->mmap_sem); + + for (vma = find_vma(mm, start); vma; vma = vma->vm_next) { + if (end <= vma->vm_start) + break; + if (vma->vm_file && + vma->vm_file->f_dentry->d_inode->i_sb == sb) + goto do_locks; + } + + if (!dumping) + up_read(&mm->mmap_sem); + } + + return operation(file, buf, size, offset, 0, &gh); + +do_locks: + return walk_vm_hard(file, buf, size, offset, operation); +} + +static ssize_t do_jdata_read(struct file *file, char __user *buf, size_t size, + loff_t *offset) +{ + struct gfs2_inode *ip = get_v2ip(file->f_mapping->host); + ssize_t count = 0; + + if (*offset < 0) + return -EINVAL; + if (!access_ok(VERIFY_WRITE, buf, size)) + return -EFAULT; + + if (!(file->f_flags & O_LARGEFILE)) { + if (*offset >= MAX_NON_LFS) + return -EFBIG; + if (*offset + size > MAX_NON_LFS) + size = MAX_NON_LFS - *offset; + } + + count = gfs2_jdata_read(ip, buf, *offset, size, gfs2_copy2user); + + if (count > 0) + *offset += count; + + return count; +} + +/** + * do_read_direct - Read bytes from a file + * @file: The file to read from + * @buf: The buffer to copy into + * @size: The amount of data requested + * @offset: The current file offset + * @num_gh: The number of other locks we need to do the read + * @ghs: the locks we need plus one for our lock + * + * Outputs: Offset - updated according to number of bytes read + * + * Returns: The number of bytes read, errno on failure + */ + +static ssize_t do_read_direct(struct file *file, char __user *buf, size_t size, + loff_t *offset, unsigned int num_gh, + struct gfs2_holder *ghs) +{ + struct inode *inode = file->f_mapping->host; + struct gfs2_inode *ip = get_v2ip(inode); + unsigned int state = LM_ST_DEFERRED; + int flags = 0; + unsigned int x; + ssize_t count = 0; + int error; + + for (x = 0; x < num_gh; x++) + if (ghs[x].gh_gl == ip->i_gl) { + state = LM_ST_SHARED; + flags |= GL_LOCAL_EXCL; + break; + } + + gfs2_holder_init(ip->i_gl, state, flags, &ghs[num_gh]); + + error = gfs2_glock_nq_m(num_gh + 1, ghs); + if (error) + goto out; + + error = -EINVAL; + if (gfs2_is_jdata(ip)) + goto out_gunlock; + + if (gfs2_is_stuffed(ip)) { + size_t mask = bdev_hardsect_size(inode->i_sb->s_bdev) - 1; + + if (((*offset) & mask) || (((unsigned long)buf) & mask)) + goto out_gunlock; + + count = do_jdata_read(file, buf, size & ~mask, offset); + } else + count = generic_file_read(file, buf, size, offset); + + error = 0; + + out_gunlock: + gfs2_glock_dq_m(num_gh + 1, ghs); + + out: + gfs2_holder_uninit(&ghs[num_gh]); + + return (count) ? count : error; +} + +/** + * do_read_buf - Read bytes from a file + * @file: The file to read from + * @buf: The buffer to copy into + * @size: The amount of data requested + * @offset: The current file offset + * @num_gh: The number of other locks we need to do the read + * @ghs: the locks we need plus one for our lock + * + * Outputs: Offset - updated according to number of bytes read + * + * Returns: The number of bytes read, errno on failure + */ + +static ssize_t do_read_buf(struct file *file, char __user *buf, size_t size, + loff_t *offset, unsigned int num_gh, + struct gfs2_holder *ghs) +{ + struct gfs2_inode *ip = get_v2ip(file->f_mapping->host); + ssize_t count = 0; + int error; + + gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &ghs[num_gh]); + + error = gfs2_glock_nq_m_atime(num_gh + 1, ghs); + if (error) + goto out; + + if (gfs2_is_jdata(ip)) + count = do_jdata_read(file, buf, size, offset); + else + count = generic_file_read(file, buf, size, offset); + + gfs2_glock_dq_m(num_gh + 1, ghs); + + out: + gfs2_holder_uninit(&ghs[num_gh]); + + return (count) ? count : error; +} + +/** + * gfs2_read - Read bytes from a file + * @file: The file to read from + * @buf: The buffer to copy into + * @size: The amount of data requested + * @offset: The current file offset + * + * Outputs: Offset - updated according to number of bytes read + * + * Returns: The number of bytes read, errno on failure + */ + +static ssize_t gfs2_read(struct file *file, char __user *buf, size_t size, + loff_t *offset) +{ + atomic_inc(&get_v2sdp(file->f_mapping->host->i_sb)->sd_ops_file); + + if (file->f_flags & O_DIRECT) + return walk_vm(file, buf, size, offset, do_read_direct); + else + return walk_vm(file, buf, size, offset, do_read_buf); +} + +/** + * grope_mapping - feel up a mapping that needs to be written + * @buf: the start of the memory to be written + * @size: the size of the memory to be written + * + * We do this after acquiring the locks on the mapping, + * but before starting the write transaction. We need to make + * sure that we don't cause recursive transactions if blocks + * need to be allocated to the file backing the mapping. + * + * Returns: errno + */ + +static int grope_mapping(const char __user *buf, size_t size) +{ + const char __user *stop = buf + size; + char c; + + while (buf < stop) { + if (copy_from_user(&c, buf, 1)) + return -EFAULT; + buf += PAGE_CACHE_SIZE; + buf = (const char __user *)PAGE_ALIGN((unsigned long)buf); + } + + return 0; +} + +/** + * do_write_direct_alloc - Write bytes to a file + * @file: The file to write to + * @buf: The buffer to copy from + * @size: The amount of data requested + * @offset: The current file offset + * + * Outputs: Offset - updated according to number of bytes written + * + * Returns: The number of bytes written, errno on failure + */ + +static ssize_t do_write_direct_alloc(struct file *file, const char __user *buf, size_t size, + loff_t *offset) +{ + struct inode *inode = file->f_mapping->host; + struct gfs2_inode *ip = get_v2ip(inode); + struct gfs2_sbd *sdp = ip->i_sbd; + struct gfs2_alloc *al = NULL; + struct iovec local_iov = { .iov_base = buf, .iov_len = size }; + struct buffer_head *dibh; + unsigned int data_blocks, ind_blocks; + ssize_t count; + int error; + + gfs2_write_calc_reserv(ip, size, &data_blocks, &ind_blocks); + + al = gfs2_alloc_get(ip); + + error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE); + if (error) + goto fail; + + error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid); + if (error) + goto fail_gunlock_q; + + al->al_requested = data_blocks + ind_blocks; + + error = gfs2_inplace_reserve(ip); + if (error) + goto fail_gunlock_q; + + error = gfs2_trans_begin(sdp, + al->al_rgd->rd_ri.ri_length + ind_blocks + + RES_DINODE + RES_STATFS + RES_QUOTA, 0); + if (error) + goto fail_ipres; + + if ((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID)) { + error = gfs2_meta_inode_buffer(ip, &dibh); + if (error) + goto fail_end_trans; + + ip->i_di.di_mode &= (ip->i_di.di_mode & S_IXGRP) ? + (~(S_ISUID | S_ISGID)) : (~S_ISUID); + + gfs2_trans_add_bh(ip->i_gl, dibh); + gfs2_dinode_out(&ip->i_di, dibh->b_data); + brelse(dibh); + } + + if (gfs2_is_stuffed(ip)) { + error = gfs2_unstuff_dinode(ip, gfs2_unstuffer_sync, NULL); + if (error) + goto fail_end_trans; + } + + count = generic_file_write_nolock(file, &local_iov, 1, offset); + if (count < 0) { + error = count; + goto fail_end_trans; + } + + error = gfs2_meta_inode_buffer(ip, &dibh); + if (error) + goto fail_end_trans; + + if (ip->i_di.di_size < inode->i_size) + ip->i_di.di_size = inode->i_size; + ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds(); + + gfs2_trans_add_bh(ip->i_gl, dibh); + gfs2_dinode_out(&ip->i_di, dibh->b_data); + brelse(dibh); + + gfs2_trans_end(sdp); + + if (file->f_flags & O_SYNC) + gfs2_log_flush_glock(ip->i_gl); + + gfs2_inplace_release(ip); + gfs2_quota_unlock(ip); + gfs2_alloc_put(ip); + + if (file->f_mapping->nrpages) { + error = filemap_fdatawrite(file->f_mapping); + if (!error) + error = filemap_fdatawait(file->f_mapping); + } + if (error) + return error; + + return count; + + fail_end_trans: + gfs2_trans_end(sdp); + + fail_ipres: + gfs2_inplace_release(ip); + + fail_gunlock_q: + gfs2_quota_unlock(ip); + + fail: + gfs2_alloc_put(ip); + + return error; +} + +/** + * do_write_direct - Write bytes to a file + * @file: The file to write to + * @buf: The buffer to copy from + * @size: The amount of data requested + * @offset: The current file offset + * @num_gh: The number of other locks we need to do the read + * @gh: the locks we need plus one for our lock + * + * Outputs: Offset - updated according to number of bytes written + * + * Returns: The number of bytes written, errno on failure + */ + +static ssize_t do_write_direct(struct file *file, const char __user *buf, size_t size, + loff_t *offset, unsigned int num_gh, + struct gfs2_holder *ghs) +{ + struct gfs2_inode *ip = get_v2ip(file->f_mapping->host); + struct gfs2_sbd *sdp = ip->i_sbd; + struct gfs2_file *fp = get_v2fp(file); + unsigned int state = LM_ST_DEFERRED; + int alloc_required; + unsigned int x; + size_t s; + ssize_t count = 0; + int error; + + if (test_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags)) + state = LM_ST_EXCLUSIVE; + else + for (x = 0; x < num_gh; x++) + if (ghs[x].gh_gl == ip->i_gl) { + state = LM_ST_EXCLUSIVE; + break; + } + + restart: + gfs2_holder_init(ip->i_gl, state, 0, &ghs[num_gh]); + + error = gfs2_glock_nq_m(num_gh + 1, ghs); + if (error) + goto out; + + error = -EINVAL; + if (gfs2_is_jdata(ip)) + goto out_gunlock; + + if (num_gh) { + error = grope_mapping(buf, size); + if (error) + goto out_gunlock; + } + + if (file->f_flags & O_APPEND) + *offset = ip->i_di.di_size; + + if (!(file->f_flags & O_LARGEFILE)) { + error = -EFBIG; + if (*offset >= MAX_NON_LFS) + goto out_gunlock; + if (*offset + size > MAX_NON_LFS) + size = MAX_NON_LFS - *offset; + } + + if (gfs2_is_stuffed(ip) || + *offset + size > ip->i_di.di_size || + ((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID))) + alloc_required = 1; + else { + error = gfs2_write_alloc_required(ip, *offset, size, + &alloc_required); + if (error) + goto out_gunlock; + } + + if (alloc_required && state != LM_ST_EXCLUSIVE) { + gfs2_glock_dq_m(num_gh + 1, ghs); + gfs2_holder_uninit(&ghs[num_gh]); + state = LM_ST_EXCLUSIVE; + goto restart; + } + + if (alloc_required) { + set_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags); + + /* split large writes into smaller atomic transactions */ + while (size) { + s = gfs2_tune_get(sdp, gt_max_atomic_write); + if (s > size) + s = size; + + error = do_write_direct_alloc(file, buf, s, offset); + if (error < 0) + goto out_gunlock; + + buf += error; + size -= error; + count += error; + } + } else { + struct iovec local_iov = { .iov_base = buf, .iov_len = size }; + struct gfs2_holder t_gh; + + clear_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags); + + error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, + GL_NEVER_RECURSE, &t_gh); + if (error) + goto out_gunlock; + + count = generic_file_write_nolock(file, &local_iov, 1, offset); + + gfs2_glock_dq_uninit(&t_gh); + } + + error = 0; + + out_gunlock: + gfs2_glock_dq_m(num_gh + 1, ghs); + + out: + gfs2_holder_uninit(&ghs[num_gh]); + + return (count) ? count : error; +} + +/** + * do_do_write_buf - Write bytes to a file + * @file: The file to write to + * @buf: The buffer to copy from + * @size: The amount of data requested + * @offset: The current file offset + * + * Outputs: Offset - updated according to number of bytes written + * + * Returns: The number of bytes written, errno on failure + */ + +static ssize_t do_do_write_buf(struct file *file, const char __user *buf, size_t size, + loff_t *offset) +{ + struct inode *inode = file->f_mapping->host; + struct gfs2_inode *ip = get_v2ip(inode); + struct gfs2_sbd *sdp = ip->i_sbd; + struct gfs2_alloc *al = NULL; + struct buffer_head *dibh; + unsigned int data_blocks, ind_blocks; + int alloc_required, journaled; + ssize_t count; + int error; + + journaled = gfs2_is_jdata(ip); + + gfs2_write_calc_reserv(ip, size, &data_blocks, &ind_blocks); + + error = gfs2_write_alloc_required(ip, *offset, size, &alloc_required); + if (error) + return error; + + if (alloc_required) { + al = gfs2_alloc_get(ip); + + error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE); + if (error) + goto fail; + + error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid); + if (error) + goto fail_gunlock_q; + + al->al_requested = data_blocks + ind_blocks; + + error = gfs2_inplace_reserve(ip); + if (error) + goto fail_gunlock_q; + + error = gfs2_trans_begin(sdp, + al->al_rgd->rd_ri.ri_length + + ind_blocks + + ((journaled) ? data_blocks : 0) + + RES_DINODE + RES_STATFS + RES_QUOTA, + 0); + if (error) + goto fail_ipres; + } else { + error = gfs2_trans_begin(sdp, + ((journaled) ? data_blocks : 0) + + RES_DINODE, + 0); + if (error) + goto fail_ipres; + } + + if ((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID)) { + error = gfs2_meta_inode_buffer(ip, &dibh); + if (error) + goto fail_end_trans; + + ip->i_di.di_mode &= (ip->i_di.di_mode & S_IXGRP) ? + (~(S_ISUID | S_ISGID)) : (~S_ISUID); + + gfs2_trans_add_bh(ip->i_gl, dibh); + gfs2_dinode_out(&ip->i_di, dibh->b_data); + brelse(dibh); + } + + if (journaled) { + count = gfs2_jdata_write(ip, buf, *offset, size, + gfs2_copy_from_user); + if (count < 0) { + error = count; + goto fail_end_trans; + } + + *offset += count; + } else { + struct iovec local_iov = { .iov_base = buf, .iov_len = size }; + + count = generic_file_write_nolock(file, &local_iov, 1, offset); + if (count < 0) { + error = count; + goto fail_end_trans; + } + + error = gfs2_meta_inode_buffer(ip, &dibh); + if (error) + goto fail_end_trans; + + if (ip->i_di.di_size < inode->i_size) + ip->i_di.di_size = inode->i_size; + ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds(); + + gfs2_trans_add_bh(ip->i_gl, dibh); + gfs2_dinode_out(&ip->i_di, dibh->b_data); + brelse(dibh); + } + + gfs2_trans_end(sdp); + + if (file->f_flags & O_SYNC || IS_SYNC(inode)) { + gfs2_log_flush_glock(ip->i_gl); + error = filemap_fdatawrite(file->f_mapping); + if (error == 0) + error = filemap_fdatawait(file->f_mapping); + if (error) + goto fail_ipres; + } + + if (alloc_required) { + gfs2_assert_warn(sdp, count != size || + al->al_alloced); + gfs2_inplace_release(ip); + gfs2_quota_unlock(ip); + gfs2_alloc_put(ip); + } + + return count; + + fail_end_trans: + gfs2_trans_end(sdp); + + fail_ipres: + if (alloc_required) + gfs2_inplace_release(ip); + + fail_gunlock_q: + if (alloc_required) + gfs2_quota_unlock(ip); + + fail: + if (alloc_required) + gfs2_alloc_put(ip); + + return error; +} + +/** + * do_write_buf - Write bytes to a file + * @file: The file to write to + * @buf: The buffer to copy from + * @size: The amount of data requested + * @offset: The current file offset + * @num_gh: The number of other locks we need to do the read + * @gh: the locks we need plus one for our lock + * + * Outputs: Offset - updated according to number of bytes written + * + * Returns: The number of bytes written, errno on failure + */ + +static ssize_t do_write_buf(struct file *file, const char __user *buf, size_t size, + loff_t *offset, unsigned int num_gh, + struct gfs2_holder *ghs) +{ + struct gfs2_inode *ip = get_v2ip(file->f_mapping->host); + struct gfs2_sbd *sdp = ip->i_sbd; + size_t s; + ssize_t count = 0; + int error; + + gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ghs[num_gh]); + + error = gfs2_glock_nq_m(num_gh + 1, ghs); + if (error) + goto out; + + if (num_gh) { + error = grope_mapping(buf, size); + if (error) + goto out_gunlock; + } + + if (file->f_flags & O_APPEND) + *offset = ip->i_di.di_size; + + if (!(file->f_flags & O_LARGEFILE)) { + error = -EFBIG; + if (*offset >= MAX_NON_LFS) + goto out_gunlock; + if (*offset + size > MAX_NON_LFS) + size = MAX_NON_LFS - *offset; + } + + /* split large writes into smaller atomic transactions */ + while (size) { + s = gfs2_tune_get(sdp, gt_max_atomic_write); + if (s > size) + s = size; + + error = do_do_write_buf(file, buf, s, offset); + if (error < 0) + goto out_gunlock; + + buf += error; + size -= error; + count += error; + } + + error = 0; + + out_gunlock: + gfs2_glock_dq_m(num_gh + 1, ghs); + + out: + gfs2_holder_uninit(&ghs[num_gh]); + + return (count) ? count : error; +} + +/** + * gfs2_write - Write bytes to a file + * @file: The file to write to + * @buf: The buffer to copy from + * @size: The amount of data requested + * @offset: The current file offset + * + * Outputs: Offset - updated according to number of bytes written + * + * Returns: The number of bytes written, errno on failure + */ + +static ssize_t gfs2_write(struct file *file, const char __user *buf, + size_t size, loff_t *offset) +{ + struct inode *inode = file->f_mapping->host; + ssize_t count; + + atomic_inc(&get_v2sdp(inode->i_sb)->sd_ops_file); + + if (*offset < 0) + return -EINVAL; + if (!access_ok(VERIFY_READ, buf, size)) + return -EFAULT; + + mutex_lock(&inode->i_mutex); + if (file->f_flags & O_DIRECT) + count = walk_vm(file, buf, size, offset, + do_write_direct); + else + count = walk_vm(file, buf, size, offset, do_write_buf); + mutex_unlock(&inode->i_mutex); + + return count; +} + +/** + * filldir_reg_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_reg_func(void *opaque, const char *name, unsigned int length, + uint64_t 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_formal_ino, 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; +} + +/** + * readdir_reg - 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 readdir_reg(struct file *file, void *dirent, filldir_t filldir) +{ + struct gfs2_inode *dip = get_v2ip(file->f_mapping->host); + struct filldir_reg fdr; + struct gfs2_holder d_gh; + uint64_t offset = file->f_pos; + int error; + + fdr.fdr_sbd = dip->i_sbd; + 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(dip, &offset, &fdr, filldir_reg_func); + + gfs2_glock_dq_uninit(&d_gh); + + file->f_pos = offset; + + return error; +} + +/** + * filldir_bad_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 + * + * For supporting NFS. + * + * Returns: 0 on success, 1 if buffer full + */ + +static int filldir_bad_func(void *opaque, const char *name, unsigned int length, + uint64_t offset, struct gfs2_inum *inum, + unsigned int type) +{ + struct filldir_bad *fdb = (struct filldir_bad *)opaque; + struct gfs2_sbd *sdp = fdb->fdb_sbd; + struct filldir_bad_entry *fbe; + + if (fdb->fdb_entry_off == fdb->fdb_entry_num || + fdb->fdb_name_off + length > fdb->fdb_name_size) + return 1; + + fbe = &fdb->fdb_entry[fdb->fdb_entry_off]; + fbe->fbe_name = fdb->fdb_name + fdb->fdb_name_off; + memcpy(fbe->fbe_name, name, length); + fbe->fbe_length = length; + fbe->fbe_offset = offset; + fbe->fbe_inum = *inum; + fbe->fbe_type = type; + + fdb->fdb_entry_off++; + fdb->fdb_name_off += length; + + if (!(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; +} + +/** + * readdir_bad - Read directory entries from a directory + * @file: The directory to read from + * @dirent: Buffer for dirents + * @filldir: Function used to do the copying + * + * For supporting NFS. + * + * Returns: errno + */ + +static int readdir_bad(struct file *file, void *dirent, filldir_t filldir) +{ + struct gfs2_inode *dip = get_v2ip(file->f_mapping->host); + struct gfs2_sbd *sdp = dip->i_sbd; + struct filldir_reg fdr; + unsigned int entries, size; + struct filldir_bad *fdb; + struct gfs2_holder d_gh; + uint64_t offset = file->f_pos; + unsigned int x; + struct filldir_bad_entry *fbe; + int error; + + entries = gfs2_tune_get(sdp, gt_entries_per_readdir); + size = sizeof(struct filldir_bad) + + entries * (sizeof(struct filldir_bad_entry) + GFS2_FAST_NAME_SIZE); + + fdb = kzalloc(size, GFP_KERNEL); + if (!fdb) + return -ENOMEM; + + fdb->fdb_sbd = sdp; + fdb->fdb_entry = (struct filldir_bad_entry *)(fdb + 1); + fdb->fdb_entry_num = entries; + fdb->fdb_name = ((char *)fdb) + sizeof(struct filldir_bad) + + entries * sizeof(struct filldir_bad_entry); + fdb->fdb_name_size = entries * GFS2_FAST_NAME_SIZE; + + 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); + goto out; + } + + error = gfs2_dir_read(dip, &offset, fdb, filldir_bad_func); + + gfs2_glock_dq_uninit(&d_gh); + + fdr.fdr_sbd = sdp; + fdr.fdr_prefetch = 0; + fdr.fdr_filldir = filldir; + fdr.fdr_opaque = dirent; + + for (x = 0; x < fdb->fdb_entry_off; x++) { + fbe = &fdb->fdb_entry[x]; + + error = filldir_reg_func(&fdr, + fbe->fbe_name, fbe->fbe_length, + fbe->fbe_offset, + &fbe->fbe_inum, fbe->fbe_type); + if (error) { + file->f_pos = fbe->fbe_offset; + error = 0; + goto out; + } + } + + file->f_pos = offset; + + out: + kfree(fdb); + + return error; +} + +/** + * 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) +{ + int error; + + atomic_inc(&get_v2sdp(file->f_mapping->host->i_sb)->sd_ops_file); + + if (strcmp(current->comm, "nfsd") != 0) + error = readdir_reg(file, dirent, filldir); + else + error = readdir_bad(file, dirent, filldir); + + return error; +} + +static int gfs2_ioctl_flags(struct gfs2_inode *ip, unsigned int cmd, unsigned long arg) +{ + unsigned int lmode = (cmd == GFS2_IOCTL_SETFLAGS) ? LM_ST_EXCLUSIVE : LM_ST_SHARED; + struct buffer_head *dibh; + struct gfs2_holder i_gh; + int error; + __u32 flags = 0, change; + + if (cmd == GFS2_IOCTL_SETFLAGS) { + error = get_user(flags, (__u32 __user *)arg); + if (error) + return -EFAULT; + } + + error = gfs2_glock_nq_init(ip->i_gl, lmode, 0, &i_gh); + if (error) + return error; + + if (cmd == GFS2_IOCTL_SETFLAGS) { + change = flags ^ ip->i_di.di_flags; + error = -EPERM; + if (change & (GFS2_DIF_IMMUTABLE|GFS2_DIF_APPENDONLY)) { + if (!capable(CAP_LINUX_IMMUTABLE)) + goto out; + } + error = -EINVAL; + if (flags & (GFS2_DIF_JDATA|GFS2_DIF_DIRECTIO)) { + if (!S_ISREG(ip->i_di.di_mode)) + goto out; + /* FIXME: Would be nice not to require the following test */ + if ((flags & GFS2_DIF_JDATA) && ip->i_di.di_size) + goto out; + } + if (flags & (GFS2_DIF_INHERIT_JDATA|GFS2_DIF_INHERIT_DIRECTIO)) { + if (!S_ISDIR(ip->i_di.di_mode)) + goto out; + } + + error = gfs2_trans_begin(ip->i_sbd, RES_DINODE, 0); + if (error) + goto out; + + error = gfs2_meta_inode_buffer(ip, &dibh); + if (error) + goto out_trans_end; + + ip->i_di.di_flags = flags; + + gfs2_trans_add_bh(ip->i_gl, dibh); + gfs2_dinode_out(&ip->i_di, dibh->b_data); + + brelse(dibh); + +out_trans_end: + gfs2_trans_end(ip->i_sbd); + } else { + flags = ip->i_di.di_flags; + } +out: + gfs2_glock_dq_uninit(&i_gh); + if (cmd == GFS2_IOCTL_GETFLAGS) { + if (put_user(flags, (__u32 __user *)arg)) + return -EFAULT; + } + return error; +} + +/** + * gfs2_ioctl - do an ioctl on a file + * @inode: the inode + * @file: the file pointer + * @cmd: the ioctl command + * @arg: the argument + * + * Returns: errno + */ + +static int gfs2_ioctl(struct inode *inode, struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct gfs2_inode *ip = get_v2ip(inode); + + atomic_inc(&ip->i_sbd->sd_ops_file); + + switch (cmd) { + case GFS2_IOCTL_IDENTIFY: { + unsigned int x = GFS2_MAGIC; + if (copy_to_user((unsigned int __user *)arg, &x, sizeof(unsigned int))) + return -EFAULT; + return 0; + + case GFS2_IOCTL_SETFLAGS: + case GFS2_IOCTL_GETFLAGS: + return gfs2_ioctl_flags(ip, cmd, arg); + } + + default: + 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 = get_v2ip(file->f_mapping->host); + struct gfs2_holder i_gh; + int error; + + atomic_inc(&ip->i_sbd->sd_ops_file); + + 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; + } + + if (gfs2_is_jdata(ip)) { + if (vma->vm_flags & VM_MAYSHARE) + error = -EOPNOTSUPP; + else + vma->vm_ops = &gfs2_vm_ops_private; + } else { + /* 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 = get_v2ip(inode); + struct gfs2_holder i_gh; + struct gfs2_file *fp; + int error; + + atomic_inc(&ip->i_sbd->sd_ops_file); + + fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL); + if (!fp) + return -ENOMEM; + + init_MUTEX(&fp->f_fl_mutex); + + fp->f_inode = ip; + fp->f_vfile = file; + + gfs2_assert_warn(ip->i_sbd, !get_v2fp(file)); + set_v2fp(file, 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; + + /* Don't let the user open O_DIRECT on a jdata file */ + + if ((file->f_flags & O_DIRECT) && gfs2_is_jdata(ip)) { + error = -EINVAL; + goto fail_gunlock; + } + + gfs2_glock_dq_uninit(&i_gh); + } + + return 0; + + fail_gunlock: + gfs2_glock_dq_uninit(&i_gh); + + fail: + set_v2fp(file, 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 = get_v2sdp(inode->i_sb); + struct gfs2_file *fp; + + atomic_inc(&sdp->sd_ops_file); + + fp = get_v2fp(file); + set_v2fp(file, 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 = get_v2ip(dentry->d_inode); + + atomic_inc(&ip->i_sbd->sd_ops_file); + gfs2_log_flush_glock(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 = get_v2ip(file->f_mapping->host); + struct gfs2_sbd *sdp = ip->i_sbd; + struct lm_lockname name = + { .ln_number = ip->i_num.no_addr, + .ln_type = LM_TYPE_PLOCK }; + + atomic_inc(&sdp->sd_ops_file); + + 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; + lock_kernel(); + tmp = posix_test_lock(file, fl); + fl->fl_type = F_UNLCK; + if (tmp) + memcpy(fl, tmp, sizeof(struct file_lock)); + unlock_kernel(); + return 0; + } else { + int error; + lock_kernel(); + error = posix_lock_file_wait(file, fl); + unlock_kernel(); + return error; + } + } + + 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); +} + +/** + * gfs2_sendfile - Send bytes to a file or socket + * @in_file: The file to read from + * @out_file: The file to write to + * @count: The amount of data + * @offset: The beginning file offset + * + * Outputs: offset - updated according to number of bytes read + * + * Returns: The number of bytes sent, errno on failure + */ + +static ssize_t gfs2_sendfile(struct file *in_file, loff_t *offset, size_t count, + read_actor_t actor, void *target) +{ + struct gfs2_inode *ip = get_v2ip(in_file->f_mapping->host); + struct gfs2_holder gh; + ssize_t retval; + + atomic_inc(&ip->i_sbd->sd_ops_file); + + gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh); + + retval = gfs2_glock_nq_atime(&gh); + if (retval) + goto out; + + if (gfs2_is_jdata(ip)) + retval = -EOPNOTSUPP; + else + retval = generic_file_sendfile(in_file, offset, count, actor, + target); + + gfs2_glock_dq(&gh); + + out: + gfs2_holder_uninit(&gh); + + return retval; +} + +static int do_flock(struct file *file, int cmd, struct file_lock *fl) +{ + struct gfs2_file *fp = get_v2fp(file); + struct gfs2_holder *fl_gh = &fp->f_fl_gh; + struct gfs2_inode *ip = fp->f_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; + + down(&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(ip->i_sbd, + 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(ip->i_sbd, !error); + } + + out: + up(&fp->f_fl_mutex); + + return error; +} + +static void do_unflock(struct file *file, struct file_lock *fl) +{ + struct gfs2_file *fp = get_v2fp(file); + struct gfs2_holder *fl_gh = &fp->f_fl_gh; + + down(&fp->f_fl_mutex); + flock_lock_file_wait(file, fl); + if (fl_gh->gh_gl) + gfs2_glock_dq_uninit(fl_gh); + up(&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 = get_v2ip(file->f_mapping->host); + struct gfs2_sbd *sdp = ip->i_sbd; + + atomic_inc(&ip->i_sbd->sd_ops_file); + + 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); +} + +struct file_operations gfs2_file_fops = { + .llseek = gfs2_llseek, + .read = gfs2_read, + .write = gfs2_write, + .ioctl = gfs2_ioctl, + .mmap = gfs2_mmap, + .open = gfs2_open, + .release = gfs2_close, + .fsync = gfs2_fsync, + .lock = gfs2_lock, + .sendfile = gfs2_sendfile, + .flock = gfs2_flock, +}; + +struct file_operations gfs2_dir_fops = { + .readdir = gfs2_readdir, + .ioctl = gfs2_ioctl, + .open = gfs2_open, + .release = gfs2_close, + .fsync = gfs2_fsync, + .lock = gfs2_lock, + .flock = gfs2_flock, +}; + |