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AJvYcCVl9FGpyz2ZsV5q8R685YCK6M+r4ody24npqD57spU3zB7vzaobjoxS68Dv23otUcDzsckJWYqJ6YemTL96VeehM4SIa1O+MQDmTSTzfQ== X-Gm-Message-State: AOJu0Yygmg7YTG1CguDlth3rs6vY/bTG5zMVTILsYGI+nDQbBFew8AD9 teChJBbSRDMqCFnOHl5C9BQQby8QC9R5WfjlVE7XFZNisqUruNm5W4duIWel0+F0PB1cKrHoONH K X-Google-Smtp-Source: AGHT+IEP6MKJldpg0B+LE4QUEpw9DZZvhya/UiGfgEjdPUnZfsO58gOJz9CBevTLve0x9ryZuY+wMw== X-Received: by 2002:a05:6e02:1c43:b0:365:25a2:1896 with SMTP id d3-20020a056e021c4300b0036525a21896mr13204189ilg.0.1709132730553; Wed, 28 Feb 2024 07:05:30 -0800 (PST) Received: from [192.168.1.150] ([198.8.77.194]) by smtp.gmail.com with ESMTPSA id v19-20020aa78513000000b006e506ff670fsm6944008pfn.147.2024.02.28.07.05.28 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 28 Feb 2024 07:05:29 -0800 (PST) Message-ID: Date: Wed, 28 Feb 2024 08:05:24 -0700 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v15 3/9] fuse: implement ioctls to manage backing files Content-Language: en-US To: Miklos Szeredi Cc: Amir Goldstein , Jingbo Xu , Bernd Schubert , linux-fsdevel@vger.kernel.org, Alessio Balsini , Christian Brauner References: <20240206142453.1906268-1-amir73il@gmail.com> <20240206142453.1906268-4-amir73il@gmail.com> <450d8b2d-c1d0-4d53-b998-74495e9eca3f@linux.alibaba.com> <4e3d80ad-3c61-4adf-b74f-0c62e468eb54@kernel.dk> From: Jens Axboe In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 2/28/24 8:01 AM, Miklos Szeredi wrote: > On Wed, 28 Feb 2024 at 15:32, Jens Axboe wrote: >> >> On 2/28/24 4:28 AM, Amir Goldstein wrote: > >>> Are fixed files visible to lsof? >> >> lsof won't show them, but you can read the fdinfo of the io_uring fd to >> see them. Would probably be possible to make lsof find and show them >> too, but haven't looked into that. > > Okay, that approach could be used with fuse as well. This isn't > perfect, but we can think improving the interface for both. Yeah agree, would be nice to either patch lsof to show them, or come up with an alternative way to expose it so it just works. >>> Do they get accounted in rlimit? of which user? >> >> The fixed file table is limited in size by RLIMIT_NOFILE by the user >> that registers it. > > That's different for fuse as the server wouldn't register the whole > file table in one go. The number of used slots could be limited by > RLIMIT_NOFILE, I think. A normal use cases is to register an empty table of that size, which is just the table itself. And then the table gets filled out as direct descriptors are opened (and closed, etc). -- Jens Axboe