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v4.10.11
  1#include <linux/fs.h>
  2#include <linux/gfp.h>
  3#include <linux/nfs.h>
  4#include <linux/nfs3.h>
  5#include <linux/nfs_fs.h>
  6#include <linux/posix_acl_xattr.h>
  7#include <linux/nfsacl.h>
  8
  9#include "internal.h"
 10#include "nfs3_fs.h"
 11
 12#define NFSDBG_FACILITY	NFSDBG_PROC
 13
 14/*
 15 * nfs3_prepare_get_acl, nfs3_complete_get_acl, nfs3_abort_get_acl: Helpers for
 16 * caching get_acl results in a race-free way.  See fs/posix_acl.c:get_acl()
 17 * for explanations.
 18 */
 19static void nfs3_prepare_get_acl(struct posix_acl **p)
 20{
 21	struct posix_acl *sentinel = uncached_acl_sentinel(current);
 22
 23	if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) {
 24		/* Not the first reader or sentinel already in place. */
 25	}
 26}
 27
 28static void nfs3_complete_get_acl(struct posix_acl **p, struct posix_acl *acl)
 29{
 30	struct posix_acl *sentinel = uncached_acl_sentinel(current);
 31
 32	/* Only cache the ACL if our sentinel is still in place. */
 33	posix_acl_dup(acl);
 34	if (cmpxchg(p, sentinel, acl) != sentinel)
 35		posix_acl_release(acl);
 36}
 37
 38static void nfs3_abort_get_acl(struct posix_acl **p)
 39{
 40	struct posix_acl *sentinel = uncached_acl_sentinel(current);
 41
 42	/* Remove our sentinel upon failure. */
 43	cmpxchg(p, sentinel, ACL_NOT_CACHED);
 44}
 45
 46struct posix_acl *nfs3_get_acl(struct inode *inode, int type)
 47{
 48	struct nfs_server *server = NFS_SERVER(inode);
 49	struct page *pages[NFSACL_MAXPAGES] = { };
 50	struct nfs3_getaclargs args = {
 51		.fh = NFS_FH(inode),
 52		/* The xdr layer may allocate pages here. */
 53		.pages = pages,
 54	};
 55	struct nfs3_getaclres res = {
 56		NULL,
 57	};
 58	struct rpc_message msg = {
 59		.rpc_argp	= &args,
 60		.rpc_resp	= &res,
 61	};
 62	int status, count;
 63
 64	if (!nfs_server_capable(inode, NFS_CAP_ACLS))
 65		return ERR_PTR(-EOPNOTSUPP);
 66
 67	status = nfs_revalidate_inode(server, inode);
 68	if (status < 0)
 69		return ERR_PTR(status);
 70
 71	/*
 72	 * Only get the access acl when explicitly requested: We don't
 73	 * need it for access decisions, and only some applications use
 74	 * it. Applications which request the access acl first are not
 75	 * penalized from this optimization.
 76	 */
 77	if (type == ACL_TYPE_ACCESS)
 78		args.mask |= NFS_ACLCNT|NFS_ACL;
 79	if (S_ISDIR(inode->i_mode))
 80		args.mask |= NFS_DFACLCNT|NFS_DFACL;
 81	if (args.mask == 0)
 82		return NULL;
 83
 84	dprintk("NFS call getacl\n");
 85	msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_GETACL];
 86	res.fattr = nfs_alloc_fattr();
 87	if (res.fattr == NULL)
 88		return ERR_PTR(-ENOMEM);
 89
 90	if (args.mask & NFS_ACL)
 91		nfs3_prepare_get_acl(&inode->i_acl);
 92	if (args.mask & NFS_DFACL)
 93		nfs3_prepare_get_acl(&inode->i_default_acl);
 94
 95	status = rpc_call_sync(server->client_acl, &msg, 0);
 96	dprintk("NFS reply getacl: %d\n", status);
 97
 98	/* pages may have been allocated at the xdr layer. */
 99	for (count = 0; count < NFSACL_MAXPAGES && args.pages[count]; count++)
100		__free_page(args.pages[count]);
101
102	switch (status) {
103		case 0:
104			status = nfs_refresh_inode(inode, res.fattr);
105			break;
106		case -EPFNOSUPPORT:
107		case -EPROTONOSUPPORT:
108			dprintk("NFS_V3_ACL extension not supported; disabling\n");
109			server->caps &= ~NFS_CAP_ACLS;
110		case -ENOTSUPP:
111			status = -EOPNOTSUPP;
112		default:
113			goto getout;
114	}
115	if ((args.mask & res.mask) != args.mask) {
116		status = -EIO;
117		goto getout;
118	}
119
120	if (res.acl_access != NULL) {
121		if ((posix_acl_equiv_mode(res.acl_access, NULL) == 0) ||
122		    res.acl_access->a_count == 0) {
123			posix_acl_release(res.acl_access);
124			res.acl_access = NULL;
125		}
126	}
127
128	if (res.mask & NFS_ACL)
129		nfs3_complete_get_acl(&inode->i_acl, res.acl_access);
130	else
131		forget_cached_acl(inode, ACL_TYPE_ACCESS);
132
133	if (res.mask & NFS_DFACL)
134		nfs3_complete_get_acl(&inode->i_default_acl, res.acl_default);
135	else
136		forget_cached_acl(inode, ACL_TYPE_DEFAULT);
137
138	nfs_free_fattr(res.fattr);
139	if (type == ACL_TYPE_ACCESS) {
140		posix_acl_release(res.acl_default);
141		return res.acl_access;
142	} else {
143		posix_acl_release(res.acl_access);
144		return res.acl_default;
145	}
146
147getout:
148	nfs3_abort_get_acl(&inode->i_acl);
149	nfs3_abort_get_acl(&inode->i_default_acl);
150	posix_acl_release(res.acl_access);
151	posix_acl_release(res.acl_default);
152	nfs_free_fattr(res.fattr);
153	return ERR_PTR(status);
154}
155
156static int __nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
157		struct posix_acl *dfacl)
158{
159	struct nfs_server *server = NFS_SERVER(inode);
160	struct nfs_fattr *fattr;
161	struct page *pages[NFSACL_MAXPAGES];
162	struct nfs3_setaclargs args = {
163		.inode = inode,
164		.mask = NFS_ACL,
165		.acl_access = acl,
166		.pages = pages,
167	};
168	struct rpc_message msg = {
169		.rpc_argp	= &args,
170		.rpc_resp	= &fattr,
171	};
172	int status = 0;
173
174	if (acl == NULL && (!S_ISDIR(inode->i_mode) || dfacl == NULL))
175		goto out;
176
177	status = -EOPNOTSUPP;
178	if (!nfs_server_capable(inode, NFS_CAP_ACLS))
179		goto out;
180
181	/* We are doing this here because XDR marshalling does not
182	 * return any results, it BUGs. */
183	status = -ENOSPC;
184	if (acl != NULL && acl->a_count > NFS_ACL_MAX_ENTRIES)
185		goto out;
186	if (dfacl != NULL && dfacl->a_count > NFS_ACL_MAX_ENTRIES)
187		goto out;
188	if (S_ISDIR(inode->i_mode)) {
189		args.mask |= NFS_DFACL;
190		args.acl_default = dfacl;
191		args.len = nfsacl_size(acl, dfacl);
192	} else
193		args.len = nfsacl_size(acl, NULL);
194
195	if (args.len > NFS_ACL_INLINE_BUFSIZE) {
196		unsigned int npages = 1 + ((args.len - 1) >> PAGE_SHIFT);
197
198		status = -ENOMEM;
199		do {
200			args.pages[args.npages] = alloc_page(GFP_KERNEL);
201			if (args.pages[args.npages] == NULL)
202				goto out_freepages;
203			args.npages++;
204		} while (args.npages < npages);
205	}
206
207	dprintk("NFS call setacl\n");
208	status = -ENOMEM;
209	fattr = nfs_alloc_fattr();
210	if (fattr == NULL)
211		goto out_freepages;
212
213	msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_SETACL];
214	msg.rpc_resp = fattr;
215	status = rpc_call_sync(server->client_acl, &msg, 0);
216	nfs_access_zap_cache(inode);
217	nfs_zap_acl_cache(inode);
218	dprintk("NFS reply setacl: %d\n", status);
219
220	switch (status) {
221		case 0:
222			status = nfs_refresh_inode(inode, fattr);
223			set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
224			set_cached_acl(inode, ACL_TYPE_DEFAULT, dfacl);
225			break;
226		case -EPFNOSUPPORT:
227		case -EPROTONOSUPPORT:
228			dprintk("NFS_V3_ACL SETACL RPC not supported"
229					"(will not retry)\n");
230			server->caps &= ~NFS_CAP_ACLS;
231		case -ENOTSUPP:
232			status = -EOPNOTSUPP;
233	}
234	nfs_free_fattr(fattr);
235out_freepages:
236	while (args.npages != 0) {
237		args.npages--;
238		__free_page(args.pages[args.npages]);
239	}
240out:
241	return status;
242}
243
244int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
245		struct posix_acl *dfacl)
246{
247	int ret;
248	ret = __nfs3_proc_setacls(inode, acl, dfacl);
249	return (ret == -EOPNOTSUPP) ? 0 : ret;
250
251}
252
253int nfs3_set_acl(struct inode *inode, struct posix_acl *acl, int type)
254{
255	struct posix_acl *alloc = NULL, *dfacl = NULL;
256	int status;
257
258	if (S_ISDIR(inode->i_mode)) {
259		switch(type) {
260		case ACL_TYPE_ACCESS:
261			alloc = dfacl = get_acl(inode, ACL_TYPE_DEFAULT);
262			if (IS_ERR(alloc))
263				goto fail;
264			break;
265
266		case ACL_TYPE_DEFAULT:
267			dfacl = acl;
268			alloc = acl = get_acl(inode, ACL_TYPE_ACCESS);
269			if (IS_ERR(alloc))
270				goto fail;
271			break;
272		}
273	}
274
275	if (acl == NULL) {
276		alloc = acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
277		if (IS_ERR(alloc))
278			goto fail;
279	}
280	status = __nfs3_proc_setacls(inode, acl, dfacl);
281	posix_acl_release(alloc);
282	return status;
283
284fail:
285	return PTR_ERR(alloc);
286}
287
288const struct xattr_handler *nfs3_xattr_handlers[] = {
289	&posix_acl_access_xattr_handler,
290	&posix_acl_default_xattr_handler,
291	NULL,
292};
293
294static int
295nfs3_list_one_acl(struct inode *inode, int type, const char *name, void *data,
296		size_t size, ssize_t *result)
297{
298	struct posix_acl *acl;
299	char *p = data + *result;
300
301	acl = get_acl(inode, type);
302	if (IS_ERR_OR_NULL(acl))
303		return 0;
304
305	posix_acl_release(acl);
306
307	*result += strlen(name);
308	*result += 1;
309	if (!size)
310		return 0;
311	if (*result > size)
312		return -ERANGE;
313
314	strcpy(p, name);
315	return 0;
316}
317
318ssize_t
319nfs3_listxattr(struct dentry *dentry, char *data, size_t size)
320{
321	struct inode *inode = d_inode(dentry);
322	ssize_t result = 0;
323	int error;
324
325	error = nfs3_list_one_acl(inode, ACL_TYPE_ACCESS,
326			XATTR_NAME_POSIX_ACL_ACCESS, data, size, &result);
327	if (error)
328		return error;
329
330	error = nfs3_list_one_acl(inode, ACL_TYPE_DEFAULT,
331			XATTR_NAME_POSIX_ACL_DEFAULT, data, size, &result);
332	if (error)
333		return error;
334	return result;
335}
v3.15
  1#include <linux/fs.h>
  2#include <linux/gfp.h>
  3#include <linux/nfs.h>
  4#include <linux/nfs3.h>
  5#include <linux/nfs_fs.h>
  6#include <linux/posix_acl_xattr.h>
  7#include <linux/nfsacl.h>
  8
  9#include "internal.h"
 
 10
 11#define NFSDBG_FACILITY	NFSDBG_PROC
 12
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 13struct posix_acl *nfs3_get_acl(struct inode *inode, int type)
 14{
 15	struct nfs_server *server = NFS_SERVER(inode);
 16	struct page *pages[NFSACL_MAXPAGES] = { };
 17	struct nfs3_getaclargs args = {
 18		.fh = NFS_FH(inode),
 19		/* The xdr layer may allocate pages here. */
 20		.pages = pages,
 21	};
 22	struct nfs3_getaclres res = {
 23		NULL,
 24	};
 25	struct rpc_message msg = {
 26		.rpc_argp	= &args,
 27		.rpc_resp	= &res,
 28	};
 29	int status, count;
 30
 31	if (!nfs_server_capable(inode, NFS_CAP_ACLS))
 32		return ERR_PTR(-EOPNOTSUPP);
 33
 34	status = nfs_revalidate_inode(server, inode);
 35	if (status < 0)
 36		return ERR_PTR(status);
 37
 38	/*
 39	 * Only get the access acl when explicitly requested: We don't
 40	 * need it for access decisions, and only some applications use
 41	 * it. Applications which request the access acl first are not
 42	 * penalized from this optimization.
 43	 */
 44	if (type == ACL_TYPE_ACCESS)
 45		args.mask |= NFS_ACLCNT|NFS_ACL;
 46	if (S_ISDIR(inode->i_mode))
 47		args.mask |= NFS_DFACLCNT|NFS_DFACL;
 48	if (args.mask == 0)
 49		return NULL;
 50
 51	dprintk("NFS call getacl\n");
 52	msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_GETACL];
 53	res.fattr = nfs_alloc_fattr();
 54	if (res.fattr == NULL)
 55		return ERR_PTR(-ENOMEM);
 56
 
 
 
 
 
 57	status = rpc_call_sync(server->client_acl, &msg, 0);
 58	dprintk("NFS reply getacl: %d\n", status);
 59
 60	/* pages may have been allocated at the xdr layer. */
 61	for (count = 0; count < NFSACL_MAXPAGES && args.pages[count]; count++)
 62		__free_page(args.pages[count]);
 63
 64	switch (status) {
 65		case 0:
 66			status = nfs_refresh_inode(inode, res.fattr);
 67			break;
 68		case -EPFNOSUPPORT:
 69		case -EPROTONOSUPPORT:
 70			dprintk("NFS_V3_ACL extension not supported; disabling\n");
 71			server->caps &= ~NFS_CAP_ACLS;
 72		case -ENOTSUPP:
 73			status = -EOPNOTSUPP;
 74		default:
 75			goto getout;
 76	}
 77	if ((args.mask & res.mask) != args.mask) {
 78		status = -EIO;
 79		goto getout;
 80	}
 81
 82	if (res.acl_access != NULL) {
 83		if ((posix_acl_equiv_mode(res.acl_access, NULL) == 0) ||
 84		    res.acl_access->a_count == 0) {
 85			posix_acl_release(res.acl_access);
 86			res.acl_access = NULL;
 87		}
 88	}
 89
 90	if (res.mask & NFS_ACL)
 91		set_cached_acl(inode, ACL_TYPE_ACCESS, res.acl_access);
 92	else
 93		forget_cached_acl(inode, ACL_TYPE_ACCESS);
 94
 95	if (res.mask & NFS_DFACL)
 96		set_cached_acl(inode, ACL_TYPE_DEFAULT, res.acl_default);
 97	else
 98		forget_cached_acl(inode, ACL_TYPE_DEFAULT);
 99
100	nfs_free_fattr(res.fattr);
101	if (type == ACL_TYPE_ACCESS) {
102		posix_acl_release(res.acl_default);
103		return res.acl_access;
104	} else {
105		posix_acl_release(res.acl_access);
106		return res.acl_default;
107	}
108
109getout:
 
 
110	posix_acl_release(res.acl_access);
111	posix_acl_release(res.acl_default);
112	nfs_free_fattr(res.fattr);
113	return ERR_PTR(status);
114}
115
116static int __nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
117		struct posix_acl *dfacl)
118{
119	struct nfs_server *server = NFS_SERVER(inode);
120	struct nfs_fattr *fattr;
121	struct page *pages[NFSACL_MAXPAGES];
122	struct nfs3_setaclargs args = {
123		.inode = inode,
124		.mask = NFS_ACL,
125		.acl_access = acl,
126		.pages = pages,
127	};
128	struct rpc_message msg = {
129		.rpc_argp	= &args,
130		.rpc_resp	= &fattr,
131	};
132	int status;
 
 
 
133
134	status = -EOPNOTSUPP;
135	if (!nfs_server_capable(inode, NFS_CAP_ACLS))
136		goto out;
137
138	/* We are doing this here because XDR marshalling does not
139	 * return any results, it BUGs. */
140	status = -ENOSPC;
141	if (acl != NULL && acl->a_count > NFS_ACL_MAX_ENTRIES)
142		goto out;
143	if (dfacl != NULL && dfacl->a_count > NFS_ACL_MAX_ENTRIES)
144		goto out;
145	if (S_ISDIR(inode->i_mode)) {
146		args.mask |= NFS_DFACL;
147		args.acl_default = dfacl;
148		args.len = nfsacl_size(acl, dfacl);
149	} else
150		args.len = nfsacl_size(acl, NULL);
151
152	if (args.len > NFS_ACL_INLINE_BUFSIZE) {
153		unsigned int npages = 1 + ((args.len - 1) >> PAGE_SHIFT);
154
155		status = -ENOMEM;
156		do {
157			args.pages[args.npages] = alloc_page(GFP_KERNEL);
158			if (args.pages[args.npages] == NULL)
159				goto out_freepages;
160			args.npages++;
161		} while (args.npages < npages);
162	}
163
164	dprintk("NFS call setacl\n");
165	status = -ENOMEM;
166	fattr = nfs_alloc_fattr();
167	if (fattr == NULL)
168		goto out_freepages;
169
170	msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_SETACL];
171	msg.rpc_resp = fattr;
172	status = rpc_call_sync(server->client_acl, &msg, 0);
173	nfs_access_zap_cache(inode);
174	nfs_zap_acl_cache(inode);
175	dprintk("NFS reply setacl: %d\n", status);
176
177	switch (status) {
178		case 0:
179			status = nfs_refresh_inode(inode, fattr);
180			set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
181			set_cached_acl(inode, ACL_TYPE_DEFAULT, dfacl);
182			break;
183		case -EPFNOSUPPORT:
184		case -EPROTONOSUPPORT:
185			dprintk("NFS_V3_ACL SETACL RPC not supported"
186					"(will not retry)\n");
187			server->caps &= ~NFS_CAP_ACLS;
188		case -ENOTSUPP:
189			status = -EOPNOTSUPP;
190	}
191	nfs_free_fattr(fattr);
192out_freepages:
193	while (args.npages != 0) {
194		args.npages--;
195		__free_page(args.pages[args.npages]);
196	}
197out:
198	return status;
199}
200
201int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
202		struct posix_acl *dfacl)
203{
204	int ret;
205	ret = __nfs3_proc_setacls(inode, acl, dfacl);
206	return (ret == -EOPNOTSUPP) ? 0 : ret;
207
208}
209
210int nfs3_set_acl(struct inode *inode, struct posix_acl *acl, int type)
211{
212	struct posix_acl *alloc = NULL, *dfacl = NULL;
213	int status;
214
215	if (S_ISDIR(inode->i_mode)) {
216		switch(type) {
217		case ACL_TYPE_ACCESS:
218			alloc = dfacl = get_acl(inode, ACL_TYPE_DEFAULT);
219			if (IS_ERR(alloc))
220				goto fail;
221			break;
222
223		case ACL_TYPE_DEFAULT:
224			dfacl = acl;
225			alloc = acl = get_acl(inode, ACL_TYPE_ACCESS);
226			if (IS_ERR(alloc))
227				goto fail;
228			break;
229		}
230	}
231
232	if (acl == NULL) {
233		alloc = acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
234		if (IS_ERR(alloc))
235			goto fail;
236	}
237	status = __nfs3_proc_setacls(inode, acl, dfacl);
238	posix_acl_release(alloc);
239	return status;
240
241fail:
242	return PTR_ERR(alloc);
243}
244
245const struct xattr_handler *nfs3_xattr_handlers[] = {
246	&posix_acl_access_xattr_handler,
247	&posix_acl_default_xattr_handler,
248	NULL,
249};