| Message ID | 095dda5e682c8367335b9fa448f2834b9435ee69.1686851158.git.bcodding@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | NFS sysfs scaffolding | expand |
Hi Benjamin, On Thu, Jun 15, 2023 at 02:07:26PM -0400, Benjamin Coddington wrote: > Create a sysfs directory for each mount that corresponds to the mount's > nfs_server struct. As the mount is being constructed, use the name > "server-n", but rename it to the "MAJOR:MINOR" of the mount after assigning > a device_id. The rename approach allows us to populate the mount's directory > with links to the various rpc_client objects during the mount's > construction. The naming convention (MAJOR:MINOR) can be used to reference > a particular NFS mount's sysfs tree. > > Signed-off-by: Benjamin Coddington <bcodding@redhat.com> I am not sure if this has been reported or fixed already, so I apologize if this is a duplicate. After this change landed in -next as commit 1c7251187dc0 ("NFS: add superblock sysfs entries"), I see the following splat when accessing a NFS server: [ 21.180403] RPC: Registered named UNIX socket transport module. [ 21.180407] RPC: Registered udp transport module. [ 21.180407] RPC: Registered tcp transport module. [ 21.180408] RPC: Registered tcp-with-tls transport module. [ 21.180408] RPC: Registered tcp NFSv4.1 backchannel transport module. [ 21.210652] Key type dns_resolver registered [ 21.297136] NFS: Registering the id_resolver key type [ 21.297140] Key type id_resolver registered [ 21.297140] Key type id_legacy registered [ 21.322237] ------------[ cut here ]------------ [ 21.322238] kobject: '(null)' (000000000804ef51): is not initialized, yet kobject_put() is being called. [ 21.322246] WARNING: CPU: 0 PID: 2501 at lib/kobject.c:728 kobject_put+0xc1/0x1d0 [ 21.322251] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace sunrpc fscache netfs overlay xt_mark snd_seq_dummy snd_hrtimer snd_seq snd_seq_device tun hid_logitech_hidpp mousedev joydev xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp nft_compat nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink bridge stp llc hid_logitech_dj hid_razer snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic vfat fat snd_sof_pci_intel_tgl snd_sof_intel_hda_common snd_soc_hdac_hda snd_sof_pci snd_sof_xtensa_dsp snd_sof_intel_hda_mlink snd_sof_intel_hda intel_rapl_msr snd_sof intel_rapl_common x86_pkg_temp_thermal snd_sof_utils intel_powerclamp snd_hda_ext_core i915 snd_soc_acpi_intel_match snd_soc_acpi snd_soc_core coretemp snd_compress eeepc_wmi kvm_intel asus_wmi snd_hda_intel i2c_algo_bit mei_hdcp mei_pxp ledtrig_audio usbhid snd_intel_dspcfg drm_buddy sparse_keymap kvm snd_hda_codec iTCO_wdt platform_profile ee1004 intel_pmc_bxt rfkill [ 21.322304] snd_hwdep intel_gtt iTCO_vendor_support irqbypass wmi_bmof snd_hda_core crct10dif_pclmul drm_display_helper crc32_pclmul polyval_clmulni polyval_generic drm_kms_helper snd_pcm gf128mul syscopyarea ghash_clmulni_intel sysfillrect sha512_ssse3 sysimgblt snd_timer aesni_intel video crypto_simd cryptd intel_cstate intel_uncore spi_nor snd intel_lpss_pci mei_me pcspkr intel_lpss cec i2c_i801 e1000e mtd i2c_smbus mei soundcore ttm idma64 wmi acpi_pad acpi_tad mac_hid pkcs8_key_parser dm_multipath drm crypto_user fuse dm_mod loop zram bpf_preload ip_tables x_tables nvme nvme_core spi_intel_pci xhci_pci spi_intel xhci_pci_renesas nvme_common btrfs blake2b_generic libcrc32c crc32c_generic crc32c_intel xor raid6_pq [ 21.322331] CPU: 0 PID: 2501 Comm: mount.nfs Not tainted 6.4.0-rc7-debug-00022-g1c7251187dc0 #1 650a78de916f9c7b93e3e16eabf8ef901a04fe73 [ 21.322333] Hardware name: ASUS System Product Name/PRIME Z590M-PLUS, BIOS 1203 10/27/2021 [ 21.322334] RIP: 0010:kobject_put+0xc1/0x1d0 [ 21.322347] Code: 00 4c 89 ef e8 00 c8 65 ff 48 85 db 74 9a f6 43 3c 01 0f 85 78 ff ff ff 48 8b 33 48 89 da 48 c7 c7 e0 91 a6 90 e8 7f 7c 40 ff <0f> 0b e9 5f ff ff ff c3 cc cc cc cc 4d 89 f1 49 c7 c0 d0 9b 61 90 [ 21.322349] RSP: 0018:ffffa94f44e93d50 EFLAGS: 00010286 [ 21.322350] RAX: 0000000000000000 RBX: ffff93d852edfc48 RCX: 0000000000000027 [ 21.322351] RDX: ffff93df7f421688 RSI: 0000000000000001 RDI: ffff93df7f421680 [ 21.322352] RBP: 00000000ffffffff R08: 0000000000000000 R09: ffffa94f44e93be0 [ 21.322353] R10: 0000000000000003 R11: ffffffff910ca808 R12: 00000000ffffffa3 [ 21.322353] R13: ffffa94f44e93d90 R14: ffff93d8a96c1000 R15: 0000000000000000 [ 21.322354] FS: 00007f6f56579740(0000) GS:ffff93df7f400000(0000) knlGS:0000000000000000 [ 21.322355] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 21.322356] CR2: 00007f0c3e6eaa48 CR3: 00000001793a2005 CR4: 0000000000770ef0 [ 21.322357] PKRU: 55555554 [ 21.322358] Call Trace: [ 21.322359] <TASK> [ 21.322360] ? kobject_put+0xc1/0x1d0 [ 21.322362] ? __warn+0x81/0x130 [ 21.322365] ? kobject_put+0xc1/0x1d0 [ 21.322367] ? report_bug+0x171/0x1a0 [ 21.322376] ? prb_read_valid+0x1b/0x30 [ 21.322379] ? handle_bug+0x3c/0x80 [ 21.322382] ? exc_invalid_op+0x17/0x70 [ 21.322384] ? asm_exc_invalid_op+0x1a/0x20 [ 21.322387] ? kobject_put+0xc1/0x1d0 [ 21.322390] nfs_free_server+0x6b/0xe0 [nfs 624204e86a6049542d6fb7844efc3f7da8452ecc] [ 21.322408] nfs4_create_server+0x234/0x350 [nfsv4 c1cc88cc5dfaa7ab85ce33d7e154b7db9d5a5f0d] [ 21.322443] nfs4_try_get_tree+0x37/0xd0 [nfsv4 c1cc88cc5dfaa7ab85ce33d7e154b7db9d5a5f0d] [ 21.322470] vfs_get_tree+0x26/0xd0 [ 21.322473] path_mount+0x4a1/0xae0 [ 21.322476] __x64_sys_mount+0x11a/0x150 [ 21.322477] do_syscall_64+0x5d/0x90 [ 21.322480] ? syscall_exit_to_user_mode+0x1b/0x40 [ 21.322482] ? do_syscall_64+0x6c/0x90 [ 21.322484] ? exc_page_fault+0x7f/0x180 [ 21.322486] entry_SYSCALL_64_after_hwframe+0x72/0xdc [ 21.322489] RIP: 0033:0x7f6f5684f08e [ 21.322509] Code: 48 8b 0d cd ec 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 9a ec 0c 00 f7 d8 64 89 01 48 [ 21.322510] RSP: 002b:00007ffc781debe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 21.322512] RAX: ffffffffffffffda RBX: 00007ffc781dee10 RCX: 00007f6f5684f08e [ 21.322512] RDX: 0000560364a99a10 RSI: 0000560364a999f0 RDI: 0000560364a99880 [ 21.322513] RBP: 0000560364a99da0 R08: 0000560364a99da0 R09: 0000000000000060 [ 21.322514] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc781dee10 [ 21.322514] R13: 0000560364a99d60 R14: 0000000000000004 R15: 0000560362f49927 [ 21.322516] </TASK> [ 21.322517] ---[ end trace 0000000000000000 ]--- [ 21.322518] ------------[ cut here ]------------ [ 21.322518] refcount_t: underflow; use-after-free. [ 21.322522] WARNING: CPU: 0 PID: 2501 at lib/refcount.c:28 refcount_warn_saturate+0xbe/0x110 [ 21.322525] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace sunrpc fscache netfs overlay xt_mark snd_seq_dummy snd_hrtimer snd_seq snd_seq_device tun hid_logitech_hidpp mousedev joydev xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp nft_compat nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink bridge stp llc hid_logitech_dj hid_razer snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic vfat fat snd_sof_pci_intel_tgl snd_sof_intel_hda_common snd_soc_hdac_hda snd_sof_pci snd_sof_xtensa_dsp snd_sof_intel_hda_mlink snd_sof_intel_hda intel_rapl_msr snd_sof intel_rapl_common x86_pkg_temp_thermal snd_sof_utils intel_powerclamp snd_hda_ext_core i915 snd_soc_acpi_intel_match snd_soc_acpi snd_soc_core coretemp snd_compress eeepc_wmi kvm_intel asus_wmi snd_hda_intel i2c_algo_bit mei_hdcp mei_pxp ledtrig_audio usbhid snd_intel_dspcfg drm_buddy sparse_keymap kvm snd_hda_codec iTCO_wdt platform_profile ee1004 intel_pmc_bxt rfkill [ 21.322551] snd_hwdep intel_gtt iTCO_vendor_support irqbypass wmi_bmof snd_hda_core crct10dif_pclmul drm_display_helper crc32_pclmul polyval_clmulni polyval_generic drm_kms_helper snd_pcm gf128mul syscopyarea ghash_clmulni_intel sysfillrect sha512_ssse3 sysimgblt snd_timer aesni_intel video crypto_simd cryptd intel_cstate intel_uncore spi_nor snd intel_lpss_pci mei_me pcspkr intel_lpss cec i2c_i801 e1000e mtd i2c_smbus mei soundcore ttm idma64 wmi acpi_pad acpi_tad mac_hid pkcs8_key_parser dm_multipath drm crypto_user fuse dm_mod loop zram bpf_preload ip_tables x_tables nvme nvme_core spi_intel_pci xhci_pci spi_intel xhci_pci_renesas nvme_common btrfs blake2b_generic libcrc32c crc32c_generic crc32c_intel xor raid6_pq [ 21.322573] CPU: 0 PID: 2501 Comm: mount.nfs Tainted: G W 6.4.0-rc7-debug-00022-g1c7251187dc0 #1 650a78de916f9c7b93e3e16eabf8ef901a04fe73 [ 21.322574] Hardware name: ASUS System Product Name/PRIME Z590M-PLUS, BIOS 1203 10/27/2021 [ 21.322575] RIP: 0010:refcount_warn_saturate+0xbe/0x110 [ 21.322576] Code: 01 01 e8 d5 e0 a9 ff 0f 0b c3 cc cc cc cc 80 3d 82 f5 7a 01 00 75 85 48 c7 c7 f0 eb a0 90 c6 05 72 f5 7a 01 01 e8 b2 e0 a9 ff <0f> 0b c3 cc cc cc cc 80 3d 60 f5 7a 01 00 0f 85 5e ff ff ff 48 c7 [ 21.322577] RSP: 0018:ffffa94f44e93d78 EFLAGS: 00010286 [ 21.322578] RAX: 0000000000000000 RBX: ffff93d852edf800 RCX: 0000000000000027 [ 21.322579] RDX: ffff93df7f421688 RSI: 0000000000000001 RDI: ffff93df7f421680 [ 21.322580] RBP: ffffffffffffffa3 R08: 0000000000000000 R09: ffffa94f44e93c08 [ 21.322580] R10: 0000000000000003 R11: ffffffff910ca808 R12: 00000000ffffffa3 [ 21.322581] R13: ffffa94f44e93d90 R14: ffff93d8a96c1000 R15: 0000000000000000 [ 21.322582] FS: 00007f6f56579740(0000) GS:ffff93df7f400000(0000) knlGS:0000000000000000 [ 21.322583] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 21.322584] CR2: 00007f0c3e6eaa48 CR3: 00000001793a2005 CR4: 0000000000770ef0 [ 21.322584] PKRU: 55555554 [ 21.322585] Call Trace: [ 21.322585] <TASK> [ 21.322586] ? refcount_warn_saturate+0xbe/0x110 [ 21.322587] ? __warn+0x81/0x130 [ 21.322589] ? refcount_warn_saturate+0xbe/0x110 [ 21.322591] ? report_bug+0x171/0x1a0 [ 21.322592] ? prb_read_valid+0x1b/0x30 [ 21.322595] ? handle_bug+0x3c/0x80 [ 21.322597] ? exc_invalid_op+0x17/0x70 [ 21.322599] ? asm_exc_invalid_op+0x1a/0x20 [ 21.322600] ? refcount_warn_saturate+0xbe/0x110 [ 21.322602] ? refcount_warn_saturate+0xbe/0x110 [ 21.322604] nfs_free_server+0x6b/0xe0 [nfs 624204e86a6049542d6fb7844efc3f7da8452ecc] [ 21.322621] nfs4_create_server+0x234/0x350 [nfsv4 c1cc88cc5dfaa7ab85ce33d7e154b7db9d5a5f0d] [ 21.322650] nfs4_try_get_tree+0x37/0xd0 [nfsv4 c1cc88cc5dfaa7ab85ce33d7e154b7db9d5a5f0d] [ 21.322675] vfs_get_tree+0x26/0xd0 [ 21.322677] path_mount+0x4a1/0xae0 [ 21.322679] __x64_sys_mount+0x11a/0x150 [ 21.322681] do_syscall_64+0x5d/0x90 [ 21.322683] ? syscall_exit_to_user_mode+0x1b/0x40 [ 21.322685] ? do_syscall_64+0x6c/0x90 [ 21.322686] ? exc_page_fault+0x7f/0x180 [ 21.322688] entry_SYSCALL_64_after_hwframe+0x72/0xdc [ 21.322691] RIP: 0033:0x7f6f5684f08e [ 21.322696] Code: 48 8b 0d cd ec 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 9a ec 0c 00 f7 d8 64 89 01 48 [ 21.322697] RSP: 002b:00007ffc781debe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 21.322698] RAX: ffffffffffffffda RBX: 00007ffc781dee10 RCX: 00007f6f5684f08e [ 21.322699] RDX: 0000560364a99a10 RSI: 0000560364a999f0 RDI: 0000560364a99880 [ 21.322699] RBP: 0000560364a99da0 R08: 0000560364a99da0 R09: 0000000000000060 [ 21.322700] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc781dee10 [ 21.322701] R13: 0000560364a99d60 R14: 0000000000000004 R15: 0000560362f49927 [ 21.322702] </TASK> [ 21.322703] ---[ end trace 0000000000000000 ]--- The configuration is just Arch Linux's (run through olddefconfig), in case it is relevant: https://gitlab.archlinux.org/archlinux/packaging/packages/linux/-/raw/main/config If there is any other information I can provide or patches I can test, I am more than happy to do so. Cheers, Nathan
On 26 Jun 2023, at 17:12, Nathan Chancellor wrote: > Hi Benjamin, > > On Thu, Jun 15, 2023 at 02:07:26PM -0400, Benjamin Coddington wrote: >> Create a sysfs directory for each mount that corresponds to the mount's >> nfs_server struct. As the mount is being constructed, use the name >> "server-n", but rename it to the "MAJOR:MINOR" of the mount after assigning >> a device_id. The rename approach allows us to populate the mount's directory >> with links to the various rpc_client objects during the mount's >> construction. The naming convention (MAJOR:MINOR) can be used to reference >> a particular NFS mount's sysfs tree. >> >> Signed-off-by: Benjamin Coddington <bcodding@redhat.com> > > I am not sure if this has been reported or fixed already, so I apologize > if this is a duplicate. After this change landed in -next as commit > 1c7251187dc0 ("NFS: add superblock sysfs entries"), I see the following > splat when accessing a NFS server: Hi Nathan, oh yes - I see there are a few paths through nfs4_init_server() where we can exit early due to an error or duplicate client, in which case nfs_free_server() tries to clean up the server kobject before it has been initialized. I think we can simply do: diff --git a/fs/nfs/client.c b/fs/nfs/client.c index 4967ac800b14..4046072663f2 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -1013,8 +1013,10 @@ void nfs_free_server(struct nfs_server *server) nfs_put_client(server->nfs_client); - nfs_sysfs_remove_server(server); - kobject_put(&server->kobj); + if (server->kobj.state_initialized) { + nfs_sysfs_remove_server(server); + kobject_put(&server->kobj); + } ida_free(&s_sysfs_ids, server->s_sysfs_id); ida_destroy(&server->lockowner_id); Are you able to test that? If not, totally fine - I think I should be able to reproduce the problem and send a patch. Ben
On Mon, Jun 26, 2023 at 05:47:21PM -0400, Benjamin Coddington wrote: > On 26 Jun 2023, at 17:12, Nathan Chancellor wrote: > > > Hi Benjamin, > > > > On Thu, Jun 15, 2023 at 02:07:26PM -0400, Benjamin Coddington wrote: > >> Create a sysfs directory for each mount that corresponds to the mount's > >> nfs_server struct. As the mount is being constructed, use the name > >> "server-n", but rename it to the "MAJOR:MINOR" of the mount after assigning > >> a device_id. The rename approach allows us to populate the mount's directory > >> with links to the various rpc_client objects during the mount's > >> construction. The naming convention (MAJOR:MINOR) can be used to reference > >> a particular NFS mount's sysfs tree. > >> > >> Signed-off-by: Benjamin Coddington <bcodding@redhat.com> > > > > I am not sure if this has been reported or fixed already, so I apologize > > if this is a duplicate. After this change landed in -next as commit > > 1c7251187dc0 ("NFS: add superblock sysfs entries"), I see the following > > splat when accessing a NFS server: > > Hi Nathan, oh yes - I see there are a few paths through nfs4_init_server() > where we can exit early due to an error or duplicate client, in which case > nfs_free_server() tries to clean up the server kobject before it has been > initialized. > > I think we can simply do: > > diff --git a/fs/nfs/client.c b/fs/nfs/client.c > index 4967ac800b14..4046072663f2 100644 > --- a/fs/nfs/client.c > +++ b/fs/nfs/client.c > @@ -1013,8 +1013,10 @@ void nfs_free_server(struct nfs_server *server) > > nfs_put_client(server->nfs_client); > > - nfs_sysfs_remove_server(server); > - kobject_put(&server->kobj); > + if (server->kobj.state_initialized) { > + nfs_sysfs_remove_server(server); > + kobject_put(&server->kobj); > + } > ida_free(&s_sysfs_ids, server->s_sysfs_id); > > ida_destroy(&server->lockowner_id); > > Are you able to test that? If not, totally fine - I think I should be able > to reproduce the problem and send a patch. Yes, that appears to work for me! Feel free to add Tested-by: Nathan Chancellor <nathan@kernel.org> to that diff if you send it along formally. Cheers, Nathan
diff --git a/fs/nfs/client.c b/fs/nfs/client.c index f50e025ae406..9aea938e4bf2 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -690,6 +690,7 @@ static int nfs_init_server(struct nfs_server *server, return PTR_ERR(clp); server->nfs_client = clp; + nfs_sysfs_add_server(server); /* Initialise the client representation from the mount data */ server->flags = ctx->flags; @@ -944,6 +945,8 @@ void nfs_server_remove_lists(struct nfs_server *server) } EXPORT_SYMBOL_GPL(nfs_server_remove_lists); +static DEFINE_IDA(s_sysfs_ids); + /* * Allocate and initialise a server record */ @@ -955,6 +958,12 @@ struct nfs_server *nfs_alloc_server(void) if (!server) return NULL; + server->s_sysfs_id = ida_alloc(&s_sysfs_ids, GFP_KERNEL); + if (server->s_sysfs_id < 0) { + kfree(server); + return NULL; + } + server->client = server->client_acl = ERR_PTR(-EINVAL); /* Zero out the NFS state stuff */ @@ -1001,6 +1010,10 @@ void nfs_free_server(struct nfs_server *server) nfs_put_client(server->nfs_client); + nfs_sysfs_remove_server(server); + kobject_put(&server->kobj); + ida_free(&s_sysfs_ids, server->s_sysfs_id); + ida_destroy(&server->lockowner_id); ida_destroy(&server->openowner_id); nfs_free_iostats(server->io_stats); @@ -1102,6 +1115,8 @@ struct nfs_server *nfs_clone_server(struct nfs_server *source, server->fsid = fattr->fsid; + nfs_sysfs_add_server(server); + error = nfs_init_server_rpcclient(server, source->client->cl_timeout, flavor); @@ -1385,6 +1400,7 @@ int __init nfs_fs_proc_init(void) void nfs_fs_proc_exit(void) { remove_proc_subtree("fs/nfsfs", NULL); + ida_destroy(&s_sysfs_ids); } #endif /* CONFIG_PROC_FS */ diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c index d3051b051a56..41c75602ff76 100644 --- a/fs/nfs/nfs4client.c +++ b/fs/nfs/nfs4client.c @@ -18,6 +18,7 @@ #include "nfs4idmap.h" #include "pnfs.h" #include "netns.h" +#include "sysfs.h" #define NFSDBG_FACILITY NFSDBG_CLIENT @@ -947,6 +948,8 @@ static int nfs4_set_client(struct nfs_server *server, set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state); server->nfs_client = clp; + nfs_sysfs_add_server(server); + return 0; } diff --git a/fs/nfs/super.c b/fs/nfs/super.c index 05ae23657527..40a866db7965 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -68,6 +68,8 @@ #include "nfs4session.h" #include "pnfs.h" #include "nfs.h" +#include "netns.h" +#include "sysfs.h" #define NFSDBG_FACILITY NFSDBG_VFS @@ -1088,6 +1090,7 @@ static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx) &sb->s_blocksize_bits); nfs_super_set_maxbytes(sb, server->maxfilesize); + nfs_sysfs_move_server_to_sb(sb); server->has_sec_mnt_opts = ctx->has_sec_mnt_opts; } @@ -1333,13 +1336,14 @@ int nfs_get_tree_common(struct fs_context *fc) } /* - * Destroy an NFS2/3 superblock + * Destroy an NFS superblock */ void nfs_kill_super(struct super_block *s) { struct nfs_server *server = NFS_SB(s); dev_t dev = s->s_dev; + nfs_sysfs_move_sb_to_server(server); generic_shutdown_super(s); nfs_fscache_release_super_cookie(s); diff --git a/fs/nfs/sysfs.c b/fs/nfs/sysfs.c index 90256a3a714e..0ff24f133a02 100644 --- a/fs/nfs/sysfs.c +++ b/fs/nfs/sysfs.c @@ -215,3 +215,62 @@ void nfs_netns_sysfs_destroy(struct nfs_net *netns) netns->nfs_client = NULL; } } + +static void nfs_sysfs_sb_release(struct kobject *kobj) +{ + /* no-op: why? see lib/kobject.c kobject_cleanup() */ +} + +static const void *nfs_netns_server_namespace(const struct kobject *kobj) +{ + return container_of(kobj, struct nfs_server, kobj)->nfs_client->cl_net; +} + +static struct kobj_type nfs_sb_ktype = { + .release = nfs_sysfs_sb_release, + .sysfs_ops = &kobj_sysfs_ops, + .namespace = nfs_netns_server_namespace, + .child_ns_type = nfs_netns_object_child_ns_type, +}; + +void nfs_sysfs_add_server(struct nfs_server *server) +{ + int ret; + + ret = kobject_init_and_add(&server->kobj, &nfs_sb_ktype, + &nfs_kset->kobj, "server-%d", server->s_sysfs_id); + if (ret < 0) + pr_warn("NFS: nfs sysfs add server-%d failed (%d)\n", + server->s_sysfs_id, ret); +} +EXPORT_SYMBOL_GPL(nfs_sysfs_add_server); + +void nfs_sysfs_move_server_to_sb(struct super_block *s) +{ + struct nfs_server *server = s->s_fs_info; + int ret; + + ret = kobject_rename(&server->kobj, s->s_id); + if (ret < 0) + pr_warn("NFS: rename sysfs %s failed (%d)\n", + server->kobj.name, ret); +} + +void nfs_sysfs_move_sb_to_server(struct nfs_server *server) +{ + const char *s; + int ret = -ENOMEM; + + s = kasprintf(GFP_KERNEL, "server-%d", server->s_sysfs_id); + if (s) + ret = kobject_rename(&server->kobj, s); + if (ret < 0) + pr_warn("NFS: rename sysfs %s failed (%d)\n", + server->kobj.name, ret); +} + +/* unlink, not dec-ref */ +void nfs_sysfs_remove_server(struct nfs_server *server) +{ + kobject_del(&server->kobj); +} diff --git a/fs/nfs/sysfs.h b/fs/nfs/sysfs.h index dc4cc9809d1b..c9f5e3677eb5 100644 --- a/fs/nfs/sysfs.h +++ b/fs/nfs/sysfs.h @@ -23,4 +23,9 @@ extern void nfs_sysfs_exit(void); void nfs_netns_sysfs_setup(struct nfs_net *netns, struct net *net); void nfs_netns_sysfs_destroy(struct nfs_net *netns); +void nfs_sysfs_add_server(struct nfs_server *s); +void nfs_sysfs_move_server_to_sb(struct super_block *s); +void nfs_sysfs_move_sb_to_server(struct nfs_server *s); +void nfs_sysfs_remove_server(struct nfs_server *s); + #endif diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h index ea2f7e6b1b0b..9e71eb357e0b 100644 --- a/include/linux/nfs_fs_sb.h +++ b/include/linux/nfs_fs_sb.h @@ -183,6 +183,7 @@ struct nfs_server { change_attr_type;/* Description of change attribute */ struct nfs_fsid fsid; + int s_sysfs_id; /* sysfs dentry index */ __u64 maxfilesize; /* maximum file size */ struct timespec64 time_delta; /* smallest time granularity */ unsigned long mount_time; /* when this fs was mounted */ @@ -259,6 +260,7 @@ struct nfs_server { /* User namespace info */ const struct cred *cred; bool has_sec_mnt_opts; + struct kobject kobj; }; /* Server capabilities */
Create a sysfs directory for each mount that corresponds to the mount's nfs_server struct. As the mount is being constructed, use the name "server-n", but rename it to the "MAJOR:MINOR" of the mount after assigning a device_id. The rename approach allows us to populate the mount's directory with links to the various rpc_client objects during the mount's construction. The naming convention (MAJOR:MINOR) can be used to reference a particular NFS mount's sysfs tree. Signed-off-by: Benjamin Coddington <bcodding@redhat.com> --- fs/nfs/client.c | 16 +++++++++++ fs/nfs/nfs4client.c | 3 ++ fs/nfs/super.c | 6 +++- fs/nfs/sysfs.c | 59 +++++++++++++++++++++++++++++++++++++++ fs/nfs/sysfs.h | 5 ++++ include/linux/nfs_fs_sb.h | 2 ++ 6 files changed, 90 insertions(+), 1 deletion(-)