diff options
| -rw-r--r-- | block/nfs.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/block/nfs.c b/block/nfs.c index 9f51cc3f10..60be45e8d9 100644 --- a/block/nfs.c +++ b/block/nfs.c @@ -1,7 +1,7 @@ /* * QEMU Block driver for native access to files on NFS shares * - * Copyright (c) 2014 Peter Lieven <pl@kamp.de> + * Copyright (c) 2014-2016 Peter Lieven <pl@kamp.de> * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal @@ -47,6 +47,7 @@ typedef struct NFSClient { bool has_zero_init; AioContext *aio_context; blkcnt_t st_blocks; + bool cache_used; } NFSClient; typedef struct NFSRPC { @@ -278,7 +279,7 @@ static void nfs_file_close(BlockDriverState *bs) } 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; @@ -330,12 +331,18 @@ static int64_t nfs_client_open(NFSClient *client, const char *filename, 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); + client->cache_used = true; #endif #ifdef LIBNFS_FEATURE_DEBUG } else if (!strcmp(qp->p[i].name, "debug")) { @@ -418,7 +425,7 @@ static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags, } 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; } @@ -454,7 +461,7 @@ static int nfs_file_create(const char *url, QemuOpts *opts, Error **errp) 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; } @@ -516,6 +523,11 @@ static int nfs_reopen_prepare(BDRVReopenState *state, return -EACCES; } + if ((state->flags & BDRV_O_NOCACHE) && client->cache_used) { + error_setg(errp, "Cannot disable cache if libnfs readahead is enabled"); + return -EINVAL; + } + /* Update cache for read-only reopens */ if (!(state->flags & BDRV_O_RDWR)) { ret = nfs_fstat(client->context, client->fh, &st); |