/*
* QEMU Block driver for native access to files on NFS shares
*
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* THE SOFTWARE.
*/
-#include "config-host.h"
+#include "qemu/osdep.h"
#include <poll.h>
#include "qemu-common.h"
#include "qemu/config-file.h"
#include "qemu/error-report.h"
+#include "qapi/error.h"
#include "block/block_int.h"
#include "trace.h"
#include "qemu/iov.h"
#include "qemu/uri.h"
+#include "qemu/cutils.h"
#include "sysemu/sysemu.h"
#include <nfsc/libnfs.h>
#define QEMU_NFS_MAX_READAHEAD_SIZE 1048576
+#define QEMU_NFS_MAX_PAGECACHE_SIZE (8388608 / NFS_BLKSIZE)
+#define QEMU_NFS_MAX_DEBUG_LEVEL 2
typedef struct NFSClient {
struct nfs_context *context;
int events;
bool has_zero_init;
AioContext *aio_context;
+ blkcnt_t st_blocks;
+ bool cache_used;
} NFSClient;
typedef struct NFSRPC {
{
int ev = nfs_which_events(client->context);
if (ev != client->events) {
- aio_set_fd_handler(client->aio_context,
- nfs_get_fd(client->context),
+ aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
+ false,
(ev & POLLIN) ? nfs_process_read : NULL,
- (ev & POLLOUT) ? nfs_process_write : NULL,
- client);
+ (ev & POLLOUT) ? nfs_process_write : NULL, client);
}
client->events = ev;
{
NFSClient *client = bs->opaque;
- aio_set_fd_handler(client->aio_context,
- nfs_get_fd(client->context),
- NULL, NULL, NULL);
+ aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
+ false, NULL, NULL, NULL);
client->events = 0;
}
if (client->fh) {
nfs_close(client->context, client->fh);
}
- aio_set_fd_handler(client->aio_context,
- nfs_get_fd(client->context),
- NULL, NULL, NULL);
+ aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
+ false, NULL, NULL, NULL);
nfs_destroy_context(client->context);
}
memset(client, 0, sizeof(NFSClient));
}
static int64_t nfs_client_open(NFSClient *client, const char *filename,
- int flags, Error **errp)
+ int flags, Error **errp, int open_flags)
{
int ret = -EINVAL, i;
struct stat st;
nfs_set_tcp_syncnt(client->context, val);
#ifdef LIBNFS_FEATURE_READAHEAD
} else if (!strcmp(qp->p[i].name, "readahead")) {
+ if (open_flags & BDRV_O_NOCACHE) {
+ error_setg(errp, "Cannot enable NFS readahead "
+ "if cache.direct = on");
+ goto fail;
+ }
if (val > QEMU_NFS_MAX_READAHEAD_SIZE) {
error_report("NFS Warning: Truncating NFS readahead"
" size to %d", QEMU_NFS_MAX_READAHEAD_SIZE);
val = QEMU_NFS_MAX_READAHEAD_SIZE;
}
nfs_set_readahead(client->context, val);
+#ifdef LIBNFS_FEATURE_PAGECACHE
+ nfs_set_pagecache_ttl(client->context, 0);
+#endif
+ client->cache_used = true;
+#endif
+#ifdef LIBNFS_FEATURE_PAGECACHE
+ nfs_set_pagecache_ttl(client->context, 0);
+ } else if (!strcmp(qp->p[i].name, "pagecache")) {
+ if (open_flags & BDRV_O_NOCACHE) {
+ error_setg(errp, "Cannot enable NFS pagecache "
+ "if cache.direct = on");
+ goto fail;
+ }
+ if (val > QEMU_NFS_MAX_PAGECACHE_SIZE) {
+ error_report("NFS Warning: Truncating NFS pagecache"
+ " size to %d pages", QEMU_NFS_MAX_PAGECACHE_SIZE);
+ val = QEMU_NFS_MAX_PAGECACHE_SIZE;
+ }
+ nfs_set_pagecache(client->context, val);
+ nfs_set_pagecache_ttl(client->context, 0);
+ client->cache_used = true;
+#endif
+#ifdef LIBNFS_FEATURE_DEBUG
+ } else if (!strcmp(qp->p[i].name, "debug")) {
+ /* limit the maximum debug level to avoid potential flooding
+ * of our log files. */
+ if (val > QEMU_NFS_MAX_DEBUG_LEVEL) {
+ error_report("NFS Warning: Limiting NFS debug level"
+ " to %d", QEMU_NFS_MAX_DEBUG_LEVEL);
+ val = QEMU_NFS_MAX_DEBUG_LEVEL;
+ }
+ nfs_set_debug(client->context, val);
#endif
} else {
error_setg(errp, "Unknown NFS parameter name: %s",
}
ret = DIV_ROUND_UP(st.st_size, BDRV_SECTOR_SIZE);
+ client->st_blocks = st.st_blocks;
client->has_zero_init = S_ISREG(st.st_mode);
goto out;
fail:
}
ret = nfs_client_open(client, qemu_opt_get(opts, "filename"),
(flags & BDRV_O_RDWR) ? O_RDWR : O_RDONLY,
- errp);
+ errp, bs->open_flags);
if (ret < 0) {
goto out;
}
total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
BDRV_SECTOR_SIZE);
- ret = nfs_client_open(client, url, O_CREAT, errp);
+ ret = nfs_client_open(client, url, O_CREAT, errp, 0);
if (ret < 0) {
goto out;
}
NFSRPC task = {0};
struct stat st;
+ if (bdrv_is_read_only(bs) &&
+ !(bs->open_flags & BDRV_O_NOCACHE)) {
+ return client->st_blocks * 512;
+ }
+
task.st = &st;
if (nfs_fstat_async(client->context, client->fh, nfs_co_generic_cb,
&task) != 0) {
aio_poll(client->aio_context, true);
}
- return (task.ret < 0 ? task.ret : st.st_blocks * st.st_blksize);
+ return (task.ret < 0 ? task.ret : st.st_blocks * 512);
}
static int nfs_file_truncate(BlockDriverState *bs, int64_t offset)
return nfs_ftruncate(client->context, client->fh, offset);
}
+/* Note that this will not re-establish a connection with the NFS server
+ * - it is effectively a NOP. */
+static int nfs_reopen_prepare(BDRVReopenState *state,
+ BlockReopenQueue *queue, Error **errp)
+{
+ NFSClient *client = state->bs->opaque;
+ struct stat st;
+ int ret = 0;
+
+ if (state->flags & BDRV_O_RDWR && bdrv_is_read_only(state->bs)) {
+ error_setg(errp, "Cannot open a read-only mount as read-write");
+ return -EACCES;
+ }
+
+ if ((state->flags & BDRV_O_NOCACHE) && client->cache_used) {
+ error_setg(errp, "Cannot disable cache if libnfs readahead or"
+ " pagecache is enabled");
+ return -EINVAL;
+ }
+
+ /* Update cache for read-only reopens */
+ if (!(state->flags & BDRV_O_RDWR)) {
+ ret = nfs_fstat(client->context, client->fh, &st);
+ if (ret < 0) {
+ error_setg(errp, "Failed to fstat file: %s",
+ nfs_get_error(client->context));
+ return ret;
+ }
+ client->st_blocks = st.st_blocks;
+ }
+
+ return 0;
+}
+
+#ifdef LIBNFS_FEATURE_PAGECACHE
+static void nfs_invalidate_cache(BlockDriverState *bs,
+ Error **errp)
+{
+ NFSClient *client = bs->opaque;
+ nfs_pagecache_invalidate(client->context, client->fh);
+}
+#endif
+
static BlockDriver bdrv_nfs = {
.format_name = "nfs",
.protocol_name = "nfs",
.bdrv_file_open = nfs_file_open,
.bdrv_close = nfs_file_close,
.bdrv_create = nfs_file_create,
+ .bdrv_reopen_prepare = nfs_reopen_prepare,
.bdrv_co_readv = nfs_co_readv,
.bdrv_co_writev = nfs_co_writev,
.bdrv_detach_aio_context = nfs_detach_aio_context,
.bdrv_attach_aio_context = nfs_attach_aio_context,
+
+#ifdef LIBNFS_FEATURE_PAGECACHE
+ .bdrv_invalidate_cache = nfs_invalidate_cache,
+#endif
};
static void nfs_block_init(void)
projects / qemu.git / blobdiff