ocfs2: factor out write aops into nolock variants

ocfs2_mkwrite() will want this so that it can add some mmap specific checks
before asking for a write.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
This commit is contained in:
Mark Fasheh 2007-05-09 15:14:45 -07:00
parent 3a307ffc27
commit 607d44aa3f

View file

@ -849,7 +849,7 @@ static void ocfs2_free_write_ctxt(struct ocfs2_write_ctxt *wc)
static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp,
struct ocfs2_super *osb, loff_t pos,
unsigned len)
unsigned len, struct buffer_head *di_bh)
{
struct ocfs2_write_ctxt *wc;
@ -859,6 +859,8 @@ static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp,
wc->w_cpos = pos >> osb->s_clustersize_bits;
wc->w_clen = ocfs2_clusters_for_bytes(osb->sb, len);
get_bh(di_bh);
wc->w_di_bh = di_bh;
if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits))
wc->w_large_pages = 1;
@ -1211,9 +1213,10 @@ static void ocfs2_set_target_boundaries(struct ocfs2_super *osb,
}
}
int ocfs2_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
static int ocfs2_write_begin_nolock(struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata,
struct buffer_head *di_bh)
{
int ret, i, credits = OCFS2_INODE_UPDATE_CREDITS;
unsigned int num_clusters = 0, clusters_to_alloc = 0;
@ -1227,28 +1230,14 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping,
handle_t *handle;
struct ocfs2_write_cluster_desc *desc;
ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len);
ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len, di_bh);
if (ret) {
mlog_errno(ret);
return ret;
}
ret = ocfs2_meta_lock(inode, &wc->w_di_bh, 1);
if (ret) {
mlog_errno(ret);
goto out;
}
di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
/*
* Take alloc sem here to prevent concurrent lookups. That way
* the mapping, zeroing and tree manipulation within
* ocfs2_write() will be safe against ->readpage(). This
* should also serve to lock out allocation from a shared
* writeable region.
*/
down_write(&OCFS2_I(inode)->ip_alloc_sem);
for (i = 0; i < wc->w_clen; i++) {
desc = &wc->w_desc[i];
desc->c_cpos = wc->w_cpos + i;
@ -1258,7 +1247,7 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping,
&num_clusters, NULL);
if (ret) {
mlog_errno(ret);
goto out_meta;
goto out;
}
} else if (phys) {
/*
@ -1293,7 +1282,7 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping,
&data_ac, &meta_ac);
if (ret) {
mlog_errno(ret);
goto out_meta;
goto out;
}
credits = ocfs2_calc_extend_credits(inode->i_sb, di,
@ -1303,17 +1292,11 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping,
ocfs2_set_target_boundaries(osb, wc, pos, len, clusters_to_alloc);
ret = ocfs2_data_lock(inode, 1);
if (ret) {
mlog_errno(ret);
goto out_meta;
}
handle = ocfs2_start_trans(osb, credits);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
mlog_errno(ret);
goto out_data;
goto out;
}
wc->w_handle = handle;
@ -1363,13 +1346,6 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping,
out_commit:
ocfs2_commit_trans(osb, handle);
out_data:
ocfs2_data_unlock(inode, 1);
out_meta:
up_write(&OCFS2_I(inode)->ip_alloc_sem);
ocfs2_meta_unlock(inode, 1);
out:
ocfs2_free_write_ctxt(wc);
@ -1380,9 +1356,60 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping,
return ret;
}
int ocfs2_write_end(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied,
struct page *page, void *fsdata)
int ocfs2_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
int ret;
struct buffer_head *di_bh = NULL;
struct inode *inode = mapping->host;
ret = ocfs2_meta_lock(inode, &di_bh, 1);
if (ret) {
mlog_errno(ret);
return ret;
}
/*
* Take alloc sem here to prevent concurrent lookups. That way
* the mapping, zeroing and tree manipulation within
* ocfs2_write() will be safe against ->readpage(). This
* should also serve to lock out allocation from a shared
* writeable region.
*/
down_write(&OCFS2_I(inode)->ip_alloc_sem);
ret = ocfs2_data_lock(inode, 1);
if (ret) {
mlog_errno(ret);
goto out_fail;
}
ret = ocfs2_write_begin_nolock(mapping, pos, len, flags, pagep,
fsdata, di_bh);
if (ret) {
mlog_errno(ret);
goto out_fail_data;
}
brelse(di_bh);
return 0;
out_fail_data:
ocfs2_data_unlock(inode, 1);
out_fail:
up_write(&OCFS2_I(inode)->ip_alloc_sem);
brelse(di_bh);
ocfs2_meta_unlock(inode, 1);
return ret;
}
static int ocfs2_write_end_nolock(struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied,
struct page *page, void *fsdata)
{
int i;
unsigned from, to, start = pos & (PAGE_CACHE_SIZE - 1);
@ -1444,14 +1471,27 @@ int ocfs2_write_end(struct file *file, struct address_space *mapping,
ocfs2_journal_dirty(handle, wc->w_di_bh);
ocfs2_commit_trans(osb, handle);
ocfs2_data_unlock(inode, 1);
up_write(&OCFS2_I(inode)->ip_alloc_sem);
ocfs2_meta_unlock(inode, 1);
ocfs2_free_write_ctxt(wc);
return copied;
}
int ocfs2_write_end(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied,
struct page *page, void *fsdata)
{
int ret;
struct inode *inode = mapping->host;
ret = ocfs2_write_end_nolock(mapping, pos, len, copied, page, fsdata);
ocfs2_data_unlock(inode, 1);
up_write(&OCFS2_I(inode)->ip_alloc_sem);
ocfs2_meta_unlock(inode, 1);
return ret;
}
const struct address_space_operations ocfs2_aops = {
.readpage = ocfs2_readpage,
.writepage = ocfs2_writepage,